Evo and Proud

The digit ratio is the length of the index finger (2^ndfinger) divided by the ring finger (4^th finger). It correlates with the degree of androgenization or estrogenization of fetal tissues, including the fetal brain. (source)

As small bands of hunter-gatherers gave way to larger and more complex societies of farmers and townsfolk, trusting relationships had to expand beyond the circle of close kin. This larger social environment posed a two-fold problem:

For trust to evolve our ancestors must have 1) overcome the incentive to defect when involved in cooperative activity, and 2) suppressed the proclivity to use violence to take resources from conspecifics, as is seen in nonhuman primates. (Gifford, 2013)

This in turn required "social rules of governance and implicit institutions that suppressed free riding, provided rules of orderly behavior that increased cooperation by making individual behavior predictable, and also protected the property rights of individuals" (Gifford, 2013).

But what, exactly, does one do with free riders and sociopaths? Traditionally, such people were excluded from society, either by ostracism or, in more serious cases, by execution. There was thus strong selection for pro-social behavior, i.e., acting honorably and peacefully with other members of society. This selection operated even when ostracism was far from permanent or total. Shunning, public shaming, or simply a bad reputation would hurt one's chances for survival and reproduction in many ways: reduced access to community goods, discrimination on the marriage market, reluctance by others to provide assistance, and so forth.

This process of selection had genetic consequences, since nearly all behavioral traits have a heritability of 40% plus or minus 20%. There was thus removal not only of antisocial individuals from society but also of antisocial predispositions from the gene pool. The corollary was that the gene pool became dominated by pro-social predispositions, particularly empathy, compliance with social rules, and high thresholds for expression of anger.

This evolution probably occurred incrementally through small changes at many genes. This is what we see with increases in human intellectual capacity, and it is probably a general rule for the evolution of complex traits. Big changes at single genes tend to have nasty side-effects elsewhere on the genome.

A recent paper has highlighted one possible evolutionary pathway: the relative degree of androgenization or estrogenization of the developing fetus (Branas-Garza et al., 2013). By varying the ratio of one to the other, it's possible to alter a wide range of behavioral tendencies. This prenatal priming of fetal tissues can be easily measured by the "digit ratio," i.e., the length of the index finger (2nd finger) divided by the length of the ring finger (4th finger). The lower your digit ratio, the more you have been androgenized before birth. The higher your digit ratio, the more you have been estrogenized before birth.

Branas-Garza et al. (2013) found that altruistic behavior is strongest among men with intermediate digit ratios:

We analyze the association between altruism in adults and the exposure to prenatal sex hormones, using the second-to-fourth digit ratio. We find an inverted U-shaped relation for left and right hands, which is very consistent for men and less systematic for women. Subjects with both high and low digit ratios give less than individuals with intermediate digit ratios. We repeat the exercise with the same subjects seven months later and find a similar association, even though subjects' behavior differs the second time they play the game.

Different environments favor different degrees of altruism. In one setting, an altruist may be admired and enjoy preferential access to community goods. In another, the same person may be ridiculed and ruthlessly exploited. Thus, according to the context, the right balance has to be struck between altruism and selfishness:

One possible interpretation of the above findings comes from stabilizing selection. Since sharing with others is socially beneficial, selfish individuals are socially excluded and their fitness affected negatively. If individuals who are exposed too much or too little do not share with others, there is an evolutionary pressure on these non-altruistic individuals, which in turn generates an indirect evolutionary pressures on the degree of exposure to prenatal sex hormones by raising survival probabilities of individuals with intermediate levels of exposure. This hypothesis is supported by observed distributions of 2D:4D in the literature, which are universally concentrated around the median values. (Branas-Garza et al., 2013)

From one population to the next, digit ratios tend to cluster around different means, perhaps because altruism has been favored or disfavored to different degrees. This social selection may have targeted other behavioral traits, notably thrill-seeking. Kornhuber et al. (2013) have found that low digit ratios are associated with video game addition. This kind of addiction may tap into a male need for risk and adventure, which may likewise have been more adaptive in some environments than in others.

References

Brañas-Garza, P., J. Kovárík, L. Neyse (2013). Second-to-fourth digit ratio has a non-monotonic impact on altruism. PLoS ONE 8(4): e60419.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0060419

Gifford Jr., A. (2013). Sociality, trust, kinship and cultural evolution, The Journal of Socio-Economics, 47, 218-227

http://www.csun.edu/~hceco001/Researchpapers/Researchpapers/socialityandtrust.pdf

Kornhuber, J., E-M. Zenses, B. Lenz, C. Stoessel, P. Bouna-Pyrrou, et al. (2013). Low 2D:4D Values are associated with video game addiction. PLoS ONE 8(11): e79539.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0079539#pone-0079539-g002

She looks nice in a long skirt. Source: Ted Talks

The year is ending, and it’s time to take stock. Which posts interested you the most? Here are the five most popular ones, with the number of visits to each post:

White skin privilege– 6923

The other slave trade– 5948
Eye color, face shape, and perceived personality traits– 5708
Cleansing the scientific literature– 4989
First, sexual transmissibility and then …? – 3578

The first two belonged to a five-part series on the white slave trade (see also Trading in fair-skinned women. Did it happen elsewhere?From Slavs to slaves, From Slavs to slaves. Part II). The existence of this trade is little known even among the well-educated, who typically react with disbelief. Surely those white slaves were fewer in number than the black slaves taken across the Atlantic. And surely all of that happened long before the Atlantic slave trade.

Wrong on both counts. Europe exported about as many slaves to the non-European world as were exported from Africa to the Americas. Eastern Europeans continued to be “harvested” until the mid-1700s and the population of the Caucasus until the mid-1800s. By comparison, the black slave trade was banned within the British Empire in 1807 and throughout the Western Hemisphere by the 1860s. The difference was qualitative and not quantitative. Black slaves were mostly male; white slaves mostly female.

In writing those posts, I wasn’t driven by a desire to slander Muslims. Many white slave girls went on to become the wives of leading men, including sultans (like Roxelana). Their slave status was a passing thing, as explained by a notable of Tunis, Mohamed Rechid, when the authorities questioned him in 1891 on his role in slave trafficking:

Q. Do you have any white slave women of Circassian or other origins?

A. No, I don’t have any.
Q. When you went to Constantinople, you didn’t bring any white slave women back with you?
A. I brought two women back with me, this is true, but they aren’t slaves. They are two sisters, one of whom is my wife. One is called Zohra and the other Daïde.
Q. If they aren’t slaves, how did you get them?
A. I bought them in Constantinople, I freed them, and I married one of them. The other one is my sister-in-law. (Dali, 2012)

In Tunis, the noblest families are partly descended from such women (Dali, 2012). The same seems true for most of North Africa and the Middle East, according to this historian of Muslim Spain:

The same convoys of booty also included women, these Frankish women who were all the more sought after in Cordova because they were blond and fair-skinned. It was among them, as among the captive women from Gascony, that the Umayyad princes chose their most pampered concubines and who, once they became mothers, were themselves raised to the rank of veritable princesses, of proven sultanesses (umm walad) who were influential and quick to enter, with the assistance of Slav eunuchs, into secret and complicated palace intrigues. But the Frankish women did not populate only the caliph's harems; the dignitaries of the khassaand the rich burghers of the cities also procured them at lavish prices, like, in the modern period, the Circassian women who have so curiously tinted the upper classes of oriental Muslim society. (Lévi-Provençal, 1953, p. 179)

Of course, many white slave women had less fortunate outcomes, never rising above the level of concubine, singing girl, or prostitute. But this is not something to feel bitter or guilty about. The past is another country. We study it so that we may better understand the present.

In this five-part series, I was responding to Cameron Russell’s argument that she and other top models are cashing in on a legacy of white privilege. In other words, if Europeans had not become so dominant socially, economically, and geopolitically, her white skin and facial features would today seem much less attractive. Well, that alternate reality did exist. Until five centuries ago, white folks were weaklings on the world scene, with large areas of their continent under the rule of outsiders. And yet, European women were greatly admired in Muslim Spain, North Africa, the Middle East, and South Asia, this being why so many of them were enslaved and exported to those regions … just because of their looks.

Eye color, face shape, and perceived personality traits

This post was about Karel Kleisner’s study on eye color and face shape. In sum, blue eyes are associated with less robust and more feminine faces, but only if the faces are male. It may be that female face shape is overdetermined, i.e., all girls are exposed to enough estrogen in the womb to feminize their faces, but only blue-eyed boys reach this level of estrogenization. Thus, to some degree, blue eyes are a female trait. This finding is consistent with the view, supported by other findings, that the most visible features of Europeans are actually femalefeatures, i.e., they are a product of a selection pressure that acted primarily on women.

I was initially taken aback on seeing the averaged blue-eyed and brown-eyed male faces that appear in Dr. Kleisner’s first paper on this subject. Surely some of those photographed subjects were partly Jewish or Roma. But, then, the brown-eyed men would have been more variable in face shape, yet they were not. And how would that reason explain why blue eyes correlated with facial feminization in men but not in women?

I have also addressed this topic in Great hair … and how it evolved and Perception of skin color in sub-Saharan Africa.

Cleansing the scientific literature

Two years ago, the Danish psychologist Helmuth Nyborg published a paper on his country’s demographic future. He made the following points:

- Contrary to official statistics, immigrant birth rates are not falling. In fact, they have been rising since 1980 and were over twice the ethnic Danish birth rate in 2009. Since 1995, the ethnic Danish birth rate has been falling.

- After rising for half a century, average national IQ began to fall in 1997. This decline has also been observed in Norway, even though average IQ has continued to rise elsewhere in line with the Flynn effect.

- By 2050, less than one fifth of the population will have IQs in the 90 to 104 range, and over half in the 70 to 85 range. Primary schools will mainly have low IQ children of sub-Saharan, Middle Eastern, North African, Latin American, and Caribbean backgrounds.

- By 2072, ethnic Danes will have fallen to 60% of the population and 33% of all births. They will become a minority around 2085.

These predictions may or may not be correct (see Does Nyborg’s study make sense?). Is the rapidity of demographic change overstated? Are the differences in IQ due to poor upbringing and hence amenable to improvement? Criticism can and should be made, but that option was passed over by three of Nyborg’s colleagues. They complained to the Danish Committee for Scientific Dishonesty, which ruled that he must withdraw his study from the scientific literature. I denounced this decision in an e-mail to Morten Østergaard, the Danish Minister for Research, Innovation, and Higher Education, as did many other academics.

I got the following reply (words bolded as in the original):

Dear Dr. Frost,

The Minister for Science, Innovation and Higher Education Morten Østergaard acknowledges receipt of your e-mail dated 14 November 2013.

Further to your concern as to the decision (ruling) dated 28 October 2013 of the Danish Committees on Scientific Dishonesty on Helmuth Nyborg’s contribution to the article “The Decay of Western Civilization: Double Relaxed Darwinian Selection” published in the scientific journal “Personality and Individual Differences”, we are now pleased to invite you to study the translation into English of the decision. You will find the translation following this link:

http://fivu.dk/en/research-and-innovation/councils-and-commissions/the-danish-committees-on-scientific-dishonesty/decisions/2013/decisions-of-28-october-2013-on-authorship-and-misleading-reference.pdf

Based on the conclusions of the Committees they recommend that the article be withdrawn. But, as you will see, the Danish Committees on Scientific Dishonesty have not in any way considered the conclusions drawn by Dr. Nyborg, nor have they ordered him to withdraw the article.

The Committees have been established as stipulated in an act of Parliament to “investigate allegations on research misconduct only, i.e. falsification, fabrication, plagiarism and other serious violation of good scientific practice committed wilfully or grossly negligent on planning, performance or reporting of research results”. The Committees are not entitled to consider cases involving the validity or truth of scientific theories or cases involving the research quality of a scientific product.

If you are interested in more information on the mandate of the Committees, you may find all the relevant regulations translated into English here:

http://fivu.dk/en/research-and-innovation/councils-and-commissions/the-danish-committees-on-scientific-dishonesty/the-danish-committees-on-scientific-dishonesty

Yours sincerely,

Charlotte Elverdam

General Counsel and
Head of Secretariat for Danish Committees on Scientific Dishonesty

Yes, it was just a recommendation, but recommendations are made to be acted upon by someone in authority. Or maybe the Committee expected that Dr. Nyborg would just voluntarily purge his study from the scientific literature? Anyhow, it’s clear that no one in authority wishes to proceed further.

First, sexual transmissibility and then …?

The scientific community is slowly realizing that microscopic parasites can manipulate human behavior. Attention is now focused on the protozoan Toxoplasma gondii, but only because we already know what it does to cats and mice. There is no reason to think that human-specific microbes have not also evolved in this direction. As the Czech biologist Jaroslav Flegr points out: “A large number of parasitic organisms […] may influence the phenotype of their human host even more than the Toxoplasma. These organisms are, however, still waiting for research teams to engage in a systematic study of their influence on the human host.”

Some of them may be surprisingly commonplace, organisms like vaginal yeast and bacterial vaginosis. See also Brainwashed by a microbe?

And now for the duds …

My year-end review would be incomplete unless I mentioned my least popular posts:

The cagots– 649

The Visual Word Form Area. Part II – 667
Thoughts on the Paris Spring– 755
More thoughts. The evolution of a word– 771
Can antiracism reform itself?– 860

I thought my worst post would be Is something afoot with Bigfoot? Yet that one had a respectable 1199 visits (the alleged yeti DNA turned out to be from a bear). Instead, the booby prize goes to ...

The cagots

In this post, together with previous ones on the Paekchong of Korea and the Burakumin of Japan, I argued that outcaste groups are evolutionarily conservative and thus tend to preserve predispositions that once were prevalent in the general population, e.g., with respect to time orientation, impulse control, anger threshold, etc.

Such groups exist in many societies, such as those of East Asia. The existence of stigmatized occupations, notably trades that involve contact with dead flesh (butchering, leather making, undertaking), provide lower-class individuals with a protected means of livelihood, but at the cost of becoming themselves stigmatized. The occupational class becomes a caste and, hence, no longer participates in the evolutionary changes that affect the general population. Over time, this caste tends to perpetuate the same behavioral profile and thus increasingly diverges from the evolving behavioral profile of the larger society, with the result that social stigmatization and genetic isolation further increase.

The situation is unlike that of England where, over the past millennium, the reproductive success of the upper and middle classes caused a demographic overflow that continually replenished the ranks of the lower classes, who had negative natural increase. Today, the population of English background, even in the lower classes, is composed of lineages that half a millennium ago were predominantly upper or middle class (Clark, 2007; Clark, 2009).

The Paris Spring, racism, and antiracism

Time will tell whether anything will come of the Paris Spring (better known as the French Spring). By “time” I mean the next year or so. Can antiracism reform itself? I doubt it. Yes, there is a growing willingness to extend the concept of “hate crime” to cases of interracial violence where the victim is white, e.g., the knockout game. But such willingness can never be more than tokenism. First, whites are the victims in most cases of interracial violence, and overwhelmingly so. Any acknowledgement of that reality would completely transform antiracism. Second, as antiracists are right to point out, non-white on white violence is less ideologically motivated than the reverse. The motive is typically a perception that whites are soft targets. “Whites don’t fight back.” In particular, they don’t fight back collectively. The White man has no friends.

In the real world, motives are less important than consequences. Humans have been ganging up on soft targets for millennia, but for most of that time they had no conscious ideological motive. Were the Thule Inuit aware that they were driving the Dorset people to extinction? Not really. They would first move into Dorset territory and work out a modus vivendi. When they became more numerous, they would drive those people out. Then they moved into the next patch of Dorset territory. And the cycle repeated again and again until the Dorset were no more.

References

Clark, G. (2007). A Farewell to Alms. A Brief Economic History of the World, Princeton University Press, Princeton and Oxford.

Clark, G. (2009) The indicted and the wealthy: surnames, reproductive success, genetic selection and social class in pre-industrial England,

http://www.econ.ucdavis.edu/faculty/gclark/Farewell%20to%20Alms/Clark%20-Surnames.pdf

Dali, I.M. (2012). Problématique du phénotype. Approche comparative des esclavages dans la Tunisie du XIXe siècle, in R. Botte and A. Stella (eds.) Couleurs de l’esclavages sur les deux rives de la Méditerranée (Moyen Âge-XXe siècle), (pp. 337-369), Paris: Éditions Karthala.

Lévi-Provençal, E. (1953). Histoire de l’Espagne musulmane, tome III, Paris: G.P. Maisonneuve.

Robert Chambers (1802-1871). His anonymously published book, Vestiges of the Natural History of Creation (1844), helped pave the way for public acceptance of Darwin’s theory of evolution. (source)

I haven't yet read Nicholas Wade's book A Troublesome Inheritance. I will venture to say, however, that it will be remembered less for its actual content than for its role in encouraging discussion of a difficult topic. In particular, it will familiarize a broad audience with the following points:

1. Biological evolution did not slow down with the advent of cultural evolution. In fact, it speeded up, particularly when farming began to replace hunting and gathering some 10,000 years ago. At that time, the pace of genetic change may have risen a hundred-fold.

2. Cultural evolution diversified the range of human environments. Instead of adapting only to differences in climate or food sources, like other animals, our species also adapted to differences in social structure, in the division of labor, in the means of subsistence, in unwritten or codified norms of conduct, in the degree of sedentary living, and in many other human-made phenomena. Our ancestors reshaped their environments, and these human-made environments reshaped them via gene-culture co-evolution.

3. This gene-culture co-evolution persisted into modern times. The English population, for instance, evolved between the twelfth and nineteenth centuries in terms of certain behavioral traits, particularly future time orientation and distaste for violence as a means to settle personal disputes. As Gregory Clark has shown, this behavioral change resulted from a demographic change—the relative reproductive success of the middle and upper classes—which altered the composition of the English gene pool. So the mantra that "we, too, were once savages" does not, in fact, deny the reality of biological evolution. It affirms it.

4. Human populations thus differ not only anatomically but also in various mental and behavioral predispositions. These differences are statistical and often apparent only when one compares large numbers of people. But even a weak statistical difference can profoundly affect how a society will develop and organize itself.

5. Finally, Richard Lewontin was right when he reported that genes vary much more within populations than between populations. He was unaware, however, that genetic variability between populations is qualitatively different from genetic variability within a population. The more a gene has value, the more it will vary across a population boundary, since such boundaries usually coincide with barriers that separate different habitats, different environments, different means of subsistence and, hence, different selection pressures. Conversely, the less a gene has value, the more it will vary within a population, that is, among individuals who share similar conditions of life. The selection pressure is uniform but this uniformity will not level out the variability of such genes within the population—much as a steam iron will smooth a rumpled shirt—since this variability is less phenotypically significant, i.e., it produces fewer functional differences that natural selection can act on.

Are there questionable points in Wade's book? Undoubtedly. But we should not wait until all issues are settled before we put pen to paper. Writing is a process where ideas are shared with a broader audience for debate. We may forget that The Origin of Species was written without any knowledge of Mendelian genetics. We may also forget, or simply not know, that Darwin’s path to public acceptance was cleared by an earlier book: Vestiges of the Natural History of Creation(1844). Although its anonymous author, Robert Chambers, had no understanding of natural selection, he nonetheless played a key role in familiarizing the public with the fossil record and the reality of biological change over time. As one historian pointed out:

It is customary among biographers of Darwin to speak of the excitement which greeted the appearance of the Origin and of Huxley's able defense of Darwin at Oxford in his clash with Bishop Wilberforce. Actually, however, by the time Darwin published, Robert Chambers had drawn much of the first wrath of the critics and the intelligent public was at least reasonably prepared to consider a more able, scientific presentation of the subject.

[…] The attacks which the scientific world launched upon the Vestiges have, in retrospect, a quite unreal character. They belabor minutiae and amateurish minor errors as though there was some subconscious recognition that the heart of the thesis was unassailable.

[…] With its publication and success as a best seller, the world of fashion discovered evolution. The restricted professional worlds of science and of theology both lost their ability to suppress or intimidate public thinking upon the matter.

[…] By 1859, when the Origin of Species was published, an aroused and eager audience was considerably prepared for the revelations of Charles Darwin. The great amateur disputant and the great professional scholar should always be remembered as having together won the public mind to evolution. (Eiseley, 1958, pp. 134, 138, 139)

References

Chambers, R. (1844). Vestiges of the Natural History of Creation, London: John Churchill

http://darwin-online.org.uk/content/frameset?itemID=A2&viewtype=text&pageseq=1

Eiseley, L. (1958). Darwin's Century. Evolution and the Men Who Discovered It, New York: Anchor Books.

Wade, N. (2014). A Troublesome Inheritance. Genes, Race and Human History, Penguin Books.

Taylor Swift (photo by David Shankbone). The physical appearance of Europeans seems to result from a selection pressure that acted primarily on women and only secondarily on men. This is especially true for highly visible traits on or near the face—the focus of visual attention.

I have just published a paper on "The puzzle of European hair, eye, and skin color." The introduction is reproduced below (reference citations have been removed for ease of reading). The full text is available here.

****************************************************

Most humans have black hair, brown eyes, and brown skin. Europeans have a different color scheme, their hair being also brown, flaxen, golden, or red, and their eyes also blue, gray, hazel, or green. Finally, their skin is pale, almost like an albino's.

How did this unusual color scheme come about? Perhaps the genetic change that lightened the skin also affected the hair and the eyes. Yet the genes are different in each case. European skin lightened mainly through the appearance of new alleles at three genes: SLC45A2, SLC24A5, and TYRP1. European hair color diversified through a proliferation of new alleles at MC1R. European eye color diversified through a proliferation of new alleles in the HERC2-OCA2 region and elsewhere.

Light skin is associated with a few of the new hair and eye color alleles, particularly the ones for red hair or blue eyes. Conceivably, these alleles may be a side effect of selection for lighter skin. But why would such selection increase the total number of alleles for hair and eye color, especially when so many of them have little or no effect on skin color? And why have neither red hair nor blue eyes reached fixation in any human population, even those with milk-white complexions?

The European color scheme has another puzzling aspect. It seems to result from a selection pressure that acted primarily on women and only secondarily on men:

- Hair color varies more in women than in men. Redheads are especially more frequent among women.

- Eye color varies more in women than in men when both copies of the so-called blue-eye allele are present, the result being a greater diversity of female eye colors wherever blue eyes are the single most common phenotype, i.e., in northern and eastern Europe.

- Blue eyes are associated in men with a more feminine face shape.

- In all human populations, women are paler than men after puberty. This post-pubescent lightening is due to sexual maturation and not to differences in sun exposure. In women, lightness of skin correlates with thickness of subcutaneous fat and with 2nd to 4th digit ratio—a marker of prenatal estrogenization. Admittedly, this sex difference is not greater in Europeans than in other populations, although it could not easily be otherwise, since Europeans are so close to the physiological limit of depigmentation.

While women are more diverse than men both in hair and eye color, this greater diversity came about differently in each case. With hair color, women have more of the intermediate hues because the darkest hue (black) is less easily expressed. With eye color, women have more of the intermediate hues because the lightest hue (blue) is less easily expressed.

In sum, European hair and eye color diversified through a selection pressure that acted on different genes via different pigmentary changes. The common denominator seems to be the creation of new visual stimuli on or near the face—the focus of visual attention.

Reference

Frost, P. (2014). The puzzle of European hair, eye, and skin color, Advances in Anthropology, 4, 78-88.

http://www.scirp.org/journal/PaperInformation.aspx?PaperID=46104

Rice paddies, China, circa 1917-1923 (source). To grow rice, you must cooperate with neighbors for irrigation and labor. Today, even with the shift to a post-agricultural society, Chinese from rice-farming areas display less individualism and more interdependence than Chinese from wheat-farming areas. Is this evidence of gene-culture co-evolution?

Human populations differ in genetic variants that influence a wide range of mental and behavioral traits. These differences are statistical, often being apparent only when one compares large numbers of individuals. Yet even a weak statistical difference can affect the way a culture develops. Furthermore, the way a culture develops may favor certain genetic variants over others.

East Asian cultures, for example, have diverged noticeably from European cultures, particularly those of Western Europe:

Western culture is more individualistic and analytic-thinking, whereas East Asian culture is more interdependent and holistic-thinking. Analytic thought uses abstract categories and formal reasoning, such as logical laws of noncontradiction—if A is true, then "not A" is false. Holistic thought is more intuitive and sometimes even embraces contradiction—both A and "not A" can be true.(Talhelm et al., 2014)

This is of course a generalization that ignores differences within each culture area. Historically, abstract thinking has been stronger among the French, whereas the English have tended toward empirical "bottom-up" thinking. A new study suggests that similar differences exist within East Asia, specifically between rice-farming areas and wheat-farming areas. In short, rice farming favors interdependence, whereas wheat farming is more conducive to individualism:

The two biggest differences between farming rice and wheat are irrigation and labor. Because rice paddies need standing water, people in rice regions build elaborate irrigation systems that require farmers to cooperate. In irrigation networks, one family's water use can affect their neighbors, so rice farmers have to coordinate their water use. Irrigation networks also require many hours each year to build, dredge, and drain—a burden that often falls on villages, not isolated individuals. (Talhelm et al., 2014)

Labor inputs are thus greater for rice growing. A husband and wife cannot farm a large enough rice paddy to support their family if they rely only on their own labor. This is not the case with wheat farming:

In comparison, wheat is easier to grow. Wheat does not need to be irrigated, so wheat farmers can rely on rainfall, which they do not coordinate with their neighbors. Planting and harvesting wheat certainly takes work, but only half as much as rice. The lighter burden means farmers can look after their own plots without relying as much on their neighbors. (Talhelm et al., 2014)

A study of 1,162 Han Chinese found differences between rice-farming and wheat-farming regions on three psychological measures: cultural thought, implicit individualism, and loyalty/nepotism.

Cultural thought

The triad task shows participants lists of three items, such as train, bus, and tracks. Participants decide which two items should be paired together. Two of the items can be paired because they belong to the same abstract category (train and bus belong to the category vehicles), and two because they share a functional relationship (trains run on tracks). People from Western and individualistic cultures choose more abstract (analytic) pairings, whereas East Asians and people from other collectivistic cultures choose more relational (holistic) pairings.

[...] People from provinces with a higher percentage of farmland devoted to rice paddies thought more holistically. [...] Northern and southern China also differ in several factors other than rice, such as climate, dialect, and contact with herding cultures. Therefore, we analyzed differences among neighboring counties in the five central provinces along the rice-wheat border. [...] People from the rice side of the border thought more holistically than people from the wheat side of the border. (Talhelm et al., 2014)

Implicit individualism

Researchers measure how large participants draw the self versus how large they draw their friends to get an implicit measure of individualism (or self-inflation). A prior study found that Americans draw themselves about 6 mm bigger than they draw others, Europeans draw themselves 3.5 mm bigger, and Japanese draw themselves slightly smaller.

People from rice provinces were more likely than people from wheat provinces to draw themselves smaller than they drew their friends. [...] On average, people from wheat provinces self-inflated 1.5 mm (closer to Europeans), and people from rice provinces self-inflated -0.03 mm (similar to Japanese). (Talhelm et al., 2014)

Loyalty/nepotism

One defining feature of collectivistic cultures is that they draw a sharp distinction between friends and strangers. A previous study measured this by having people imagine going into a business deal with (i) an honest friend, (ii) a dishonest friend, (iii) an honest stranger, and (iv) a dishonest stranger. In the stories, the friend or stranger's lies cause the participant to lose money in a business deal, and the honesty causes the participant to make more money. In each case, the participants have a chance to use their own money to reward or punish the other person.

The original study found that Singaporeans rewarded their friends much more than they punished them, which could be seen positively as loyalty or negatively as nepotism. Americans were much more likely than Singaporeans to punish their friends for bad behavior.

[...] People from rice provinces were more likely to show loyalty/nepotism [...]. In their treatment of strangers, people from rice and wheat provinces did not differ.(Talhelm et al., 2014)

Gene-culture co-evolution?

Interestingly, these findings come from people who have no connection to farming of either sort. If these psychological traits have survived the transition to a post-agricultural and largely urban society, how are they passed on? The question is raised by the authors:

[…] perhaps the parts of culture and thought style we measured are more resistant to change. Or perhaps modernization simply takes more generations to change cultural interdependence and thought style. However, most of our participants were born after China's reform and opening, which started in 1978. Furthermore, Japan, South Korea, and Hong Kong modernized much earlier than China, but they still score less individualistic on international studies of culture than their wealth would predict. (Talhelm et al., 2014)

The authors do not use the term "gene-culture co-evolution" but this seems to be the explanation they implicitly favor. Over many generations, rice farming has selected for a certain package of psychological traits, i.e., less abstract thinking and more functional "holistic" thinking; less individualism and more collectivism; and less impartiality toward strangers and more favoritism towards kin and friends.

The predominance of rice farming in East Asia may thus explain why East Asian cultures have developed their pattern of psychological traits:

The rice theory can explain wealthy East Asia's strangely persistent interdependence. China has a rice-wheat split, but Japan and South Korea are complete rice cultures. Most of China's wheat provinces devote less than 20% of farmland to rice paddies. None of Japan's 9 regions or South Korea's 16 regions has that little rice (except for two outlying islands). Japan and Korea's rice legacies could explain why they are still much less individualistic than similarly wealthy countries.(Talhelm et al., 2014)

References

Talhelm, T., X. Zhang, S. Oishi, C. Shimin, D. Duan, X. Lan, and S. Kitayama. (2014). Large-scale psychological differences within China explained by rice versus wheat agriculture, Science, 344, 603-607.

http://www.sciencemag.org/content/344/6184/603.short

Geographic prevalence of the new allele for blond hair (Guenther et al., 2014). Just one of many alleles that create the European palette of hair and eye colors.

There is a widespread belief that whatever made Europeans fair-skinned also gave them their unique palette of hair and eye colors. In reality, fair skin has only a weak genetic linkage with either non-black hair or non-brown eyes:

If we were to take all the human beings in the world who have dark brown eyes and black or dark brown hair, we would not only have the vast majority of the human species, but would have a group which shows virtually the complete range of human skin color, from black to almost completely depigmented. (Brues, 1975)

Hair color and eye color are largely uncoupled from skin color in our species—or rather in Europeans, to be more precise. It looks as if the pressure of selection has moved European color traits in different directions, on the one hand making the skin progressively lighter, and on the other making the hair and the eyes more and more diversely hued.

There have thus been different changes at different genes. European skin lightened mainly through the appearance of new alleles at three genes: SLC45A2, SLC24A5, and TYRP1. European hair color diversified through a proliferation of new alleles at MC1R. European eye color diversified through a proliferation of new alleles in the HERC2-OCA2 region and elsewhere.

In a recent study, Guenther et al. (2014) have shown that new alleles for European hair color proliferated not only at MC1R but also at other genes. In particular, blond hair seems to be due to an allele near KITLG, although other loci in this region seem involved as well. Thus, the diverse palette of European hair colors is not a side effect of a single genetic change. It is due to a proliferation of new alleles at many different places on the human genome. The only common element seems to be a selection pressure for more hair colors.

Guenther et al. (2014) likewise note that changes to hair color and eye color became uncoupled from changes to skin color in ancestral Europeans:

Some human pigmentation variants alter general aspects of pigment biosynthesis, producing changes in all melanocytes, and therefore have pleiotropic effects on hair, skin and eye color. However, it is well known that hair and eye color can also vary independently, producing common human phenotypes such as light-haired individuals with brown eyes or brown-haired individuals with blue eyes. The rs12821256 variant alters an enhancer that is active specifically in the hair follicle environment, providing a simple genetic explanation for previous observations that this SNP is associated with changes in hair pigmentation but not eye pigmentation in northern Europeans.

Why this uncoupling of European hair, eye, and skin color? These three color traits have probably undergone divergent selection pressures. Moreover, in all three cases the selection pressure seems to have acted primarily on women and only secondarily on men—an indication of some form of sexual selection where women were the sex in short supply (Frost, 2014). Because skin color is sexually dimorphic in all humans, with women being the "fair sex," this dimorphism may have biased sexual selection in the direction of increasingly lighter skin.

Hair and eye color, however, had no preexistent sexual dimorphism. So sexual selection was driven simply by a desire for bright or novel colors. In other words, whenever a new color arose through mutation, it would have initially benefited from sexual selection. As it became more and more common in the population, this selection pressure would have gradually diminished until the new color had become as prevalent as other existing hues. As a result, the palette of hair and eye colors would have steadily grown larger and larger (Frost, 2006; Frost, 2014).

References

Brues, A.M. (1975). Rethinking human pigmentation, American Journal of Physical Anthropology, 43, 387-391.

Frost, P. (2006). European hair and eye color - A case of frequency-dependent sexual selection? Evolution and Human Behavior, 27, 85-103.

Frost, P. (2014). The puzzle of European hair, eye, and skin color, Advances in Anthropology, 4, 78-88.

http://www.scirp.org/journal/PaperInformation.aspx?PaperID=46104

Guenther, C.A., B. Tasic, L. Luo, M.A. Bedell, and D.M. Kingsley. (2014). A molecular basis for classic blond hair color in Europeans, Nature Genetics, advance online

http://www.nature.com/ng/journal/vaop/ncurrent/full/ng.2991.html

Taiwanese aboriginal children, Bunun village (source: Jeremy Kemp). 60-70% of Taiwanese aborigines have a loss-of-function allele at the main hair color gene, MC1R, yet their hair is as black as humans with the original “African” allele. This seems to be a general pattern in Asians. They have fewer MC1R alleles than do Europeans, and the ones they have produce the same hair color.

When I first wrote about the puzzle of European hair and eye color, a common explanation was Neanderthal admixture. Modern humans intermixed with Neanderthals in Europe, and one legacy of this intermixture is the high prevalence of non-black hair and non-brown eyes we see in present-day Europeans.

I was skeptical. Scientists had already retrieved mtDNA from the remains of Neanderthals and early modern humans, and there was no discernible genetic continuity between the two. Neanderthal admixture seemed minor and could hardly account for the high proportion of Europeans who deviate from the species norm of black hair and brown eyes (Frost, 2006).

With the sequencing of the Neanderthal genome, it became apparent that some admixture had taken place, but only on the order of 1 to 4% in modern Eurasians. Neanderthals did resemble modern humans in having the same main gene for hair color, i.e., MC1R, but the Neanderthal allele at that gene was unlike any allele in modern humans (Lalueza-Fox et al., 2007). Moreover, there was no evidence of the polymorphism that exists for European hair color. The same allele was present in the two Neanderthal individuals that had been sampled.

That seemed to be the end of the story. A new twist, however, has been added by a recent paper. Ding et al. (2014) have found that one of the MC1R alleles in modern humans (Val92Met) appears to be of Neanderthal origin:

In this paper, we present evidences of Neanderthal introgression encompassing the MSH receptor gene MC1R. Furthermore, our evidences support that the derived allele at the functional variant Val92Met of MC1R(i.e., rs2228479*A) is likely of two origins: the vast majority of haplotypes carrying this allele in the human gene pool is resulted from Neanderthal introgression, while one haplotype (NA19084_a) carrying this allele may be from a recurrent mutation in the AMH linage, double recombination, or biased gene conversion.

This finding is consistent with the theory, first advanced by Gregory Cochran, that archaic admixture made it easier for modern humans to adapt to new environments. To be sure, Val92Met is only one of eleven derived MCIR alleles that exist in modern humans. But Ding et al. (2014) also believe that some of these other MC1R alleles are mosaics of Neanderthal and non-Neanderthal segments. So Neanderthal admixture may have helped European hair color to diversify by providing raw material for selection to act on.

A silent allele or a silenced allele?

By itself, Neanderthal admixture cannot explain the unusual diversity of hair color in present-day Europeans. It simply provided some of the raw material for this evolutionary development, and in most cases this raw material had to undergo further changes, through mutation and recombination, before it could become useful.

Indeed, despite being a loss-of-function allele, Val92Met seems to produce the same black hair as the original "African" allele. This may be seen in its geographic distribution: ~5% in Europeans, ~30% in continental East Asians, and 60-70% in Taiwanese aborigines (Ding et al., 2014). It has also been reported in South Asians, Papua-New Guineans, Japanese, and Inuit (Harding et al., 2000). Ding et al. (2014) state that this allele is associated with red hair, but the study they cite found only one individual with Val92Met among the 21 redheads examined (Valverde et al., 1995). This proportion is almost identical to the allele's incidence among Europeans in general. More likely than not, that single individual owed her red hair to an allele somewhere else on her genome.

Hair color is much less diverse in Asians, and this is reflected in lower MC1R diversity. Whereas Europeans have eleven MC1Ralleles, Asians have only five, and all five produce the same black hair color (Harding et al., 2000). In short, Asians have fewer alleles and proportionately fewer of these differ phenotypically from the ancestral African allele. It looks as if something downstream prevents these alleles from affecting hair color.

As I've argued elsewhere, Europe's diverse palette of hair and eye colors is due to unusual evolutionary circumstances, i.e., intense sexual selection of women within an ecozone (continental steppe-tundra of the last ice age) where almost all food was obtained through long-distance hunting. The consequently higher death rate and lower polygyny rate among hunters dried up the pool of men available for mating and increased competition by women for mates. Women were more strongly selected for eye-catching traits, particularly bright or novel hues, thus creating an increasingly diverse palette of hair and eye colors (Frost, 2006; Frost, 2014).

This ecozone was more suitable for continuous human settlement in Europe than in northern Asia, where it was farther north and farther removed from the moderating influence of the Atlantic. A site in central Siberia from the last ice age has yielded human DNA that shows strong affinities with present-day Europeans and Amerindians, but much less affinity with present-day northern Asians, who seem to be largely the product of repeopling from the south near the end of the last ice age (Maanasa et al., 2014). Europeans have thus better preserved the legacy of this episode of intense sexual selection.

Perhaps the story ends there. Present-day Asians have preserved less of that MC1R diversity and what they have preserved has less functional significance. Or perhaps that diversity was initially functional and then gradually ceased to be functional … because of some other selection pressure? Perhaps, at the end of the last ice age, there was some non-black hair among northern Asians, though much less than among Europeans. Being less common and thus less normal, and no longer favored by intense sexual selection, there may have been stronger social selection to eliminate deviant hair colors.

A similar kind of social selection might explain why red hair is less common than blond hair among Europeans, i.e., stigmatization of redheads that was ultimately due to a mental association between red hair and menstrual blood (Frost, 2012).

There may be a story behind these "silent alleles."

References

Ding, Q., Y. Hu, S. Xu, C. Wang, H. Li, R. Zhang, S. Yan, J. Wang, and L. Jin (2014). Neanderthal origin of the haplotypes carrying the functional variant Val92Met in the MC1R in modern humans, Molecular Biology and Evolution, published online June 10, 2014

http://mbe.oxfordjournals.org/content/early/2014/06/02/molbev.msu180.abstract

Frost, P. (2006). European hair and eye color - A case of frequency-dependent sexual selection? Evolution and Human Behavior, 27, 85-103.

Frost, P. (2012). Why are redheads less common than blondes? Evo and Proud, March 10

http://evoandproud.blogspot.ca/2012/03/why-are-redheads-less-common-than.html

Frost, P. (2014). The puzzle of European hair, eye, and skin color, Advances in Anthropology, 4, 78-88.

http://www.scirp.org/journal/PaperInformation.aspx?PaperID=46104

Harding, R.M., Healy, E., Ray, A.J., Ellis, N.S., Flanagan, N., Todd, C., Dixon, C., Sajantila, A., Jackson, I.J., Birch-Machin, M.A., and Rees, J.L. (2000). Evidence for variable selective pressures at MC1R. American Journal of Human Genetics, 66, 1351-1361.

Lalueza-Fox, C., H. Römpler, D. Caramelli, C. Stäubert, G. Catalano, D. Hughes, N. Rohland, E. Pilli, L. Longo, S. Condemi, M. de la Rasilla, J. Fortea, A. Rosas, M. Stoneking, T. Schöneberg, J. Bertranpetit, and M. Hofreiter. (2007). A melanocortin 1 receptor allele suggests varying pigmentation among Neanderthals, Science, 318 (5855), 1453-1455.

http://www.bio.davidson.edu/courses/genomics/Exams/2009/Neaderthal_pigment.pdf

Maanasa, R., Skoglund, P., Graf, K.E., Metspalu, M., Albrechtsen, A., Moltke, I., Rasmussen, S., Stafford Jr, T.W., Orlando, L., Metspalu, E., Karmin, M., Tambets, K., Roots, S., Mägi, R., Campos, P.F., Balanovska, E., Balanovsky, O., Khusnutdinova, E., Litvinov, S., Osipova, L.P., Fedorova, S.A., Voevoda, M.I., DeGiorgio, M., Sicheritz-Ponten, T., Brunak, S., Demeshchenko, S., Kivisild, T., Villems, R., Nielsen, R., Jakobsson, M., and Willerslev, E. (2014). Upper Palaeolithic Siberian genome reveals dual ancestry of Native Americans. Nature, 505, 87-91.

http://cteg.berkeley.edu/~nielsen/wordpress/wp-content/uploads/2013/12/Raghavan-M.-et-al.-2013..pdf

Valverde, P., E. Healy, I. Jackson, J.L. Rees, and J. Thody. (2005). Variants of the melanocyte-stimulating hormone receptor gene are associated with red hair and fair skin in humans, Nature Genetics, 11, 328-330.

http://www.nature.com/ng/journal/v11/n3/abs/ng1195-328.html

I’ve published a second article in Open Behavioral Genetics: “Negotiating the gap. Four academics and the dilemma of human biodiversity.” You can read it as a PDF here or as a caliber ebook here. The foreword is reproduced below. Comments are welcome.

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Twenty-five years ago I met a professor from the medical faculty who had decided to go into anthropology. He was excited by the concept of gene-culture co-evolution and wanted to get in on the action. But he stressed the need for "prudence." He would first earn his credentials as an anthropologist before tackling this sensitive subject, and he would do so gradually and prudently.

He was already a man of a certain age, and I wondered whether he would have time for all of this, but I said nothing. He knew better than me how to plan his life. And his proposal for research on gene-culture co-evolution had been thoroughly worked out. This was no back-of-the-envelope thing.

Over the next quarter-century he carried out fieldwork and published journal articles, but he never touched the subject that had inspired his move to anthropology. Did he change his mind? I suspect the reason was less thought out. Once you begin your research from a certain angle, it is hard to break away and approach it from a totally different angle—you would have to find new sources of funding and make friends with new people. You would also lose friends. So you take the easy way out, for the time being. And you wait for the right moment, which never comes.

Charles Darwin himself had fallen into that trap. When a non-biologist anonymously wrote and marketed a book about evolution, Vestiges of the Natural History of Creation, the resulting controversy impressed on Darwin the need to become a reputable biologist before writing on the topic. So he bided his time and published, published, published … on other topics in biology. One day, however, fate forced his hand. Another biologist sent him a manuscript that set out the very theory that Darwin had kept under wraps for so long. The rest is history.

You may be thinking: "That was Darwin, and this is me. And my situation is different, very different. And this is a completely different issue. It's really important for me to wait until the time is right!"

I hear you. Maybe your situation is different. And who am I to judge?

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This essay presents four academics—Richard Dawkins, Claude Lévi-Strauss, John Tooby, and Leda Cosmides—and how they negotiated the gap between personal conviction and mainstream discourse. All four came to the conclusion that human populations differ not only anatomically but also in various mental and behavioral predispositions. These differences are statistical and often apparent only between large groups of people. But even a weak statistical difference can affect how a society will develop and organize itself. Human biodiversity is therefore a reality, and one we ignore at our peril.

Yet most academics do ignore it, their ignorance being either real or feigned. It is easy to forgive the truly ignorant. But what about the ones who know better? What's their excuse? "I don't have tenure yet.""I'm not well enough known yet.""I don't have enough clout yet." Some will just say: "Please come into my office. Others may hear us talking in the corridor."

And so, among those who do know better, the common response is ... no response. But what else is there to do? How does one go about saying something that is offensive to most people? Is it better to do it gradually? Or all at once? Or is it better to say nothing at all and wait for someone else to speak out?

There are no easy answers, and that may be part of the problem. Too many people are looking for answers that are easy—that cost little in terms of reputation, career prospects, or acceptance at the next cocktail party. Why not instead assume that everything worthwhile has a cost and then look for ways to minimize the cost?

Once you accept that rule of life, everything will fall into place. This intellectual maturity became a source of strength for one of the above academics, Claude Lévi-Strauss, who had to face bitter criticism for what he said. There was an énorme scandale. People were upset and shocked. Yet he carried on as if nothing terrible had happened. Was he so fascinated by his ideas that he simply ignored what others might think? Perhaps. More likely than not, he pondered his dilemma, weighed the pros and cons, and decided that the only sensible thing was to speak out.

How will you decide? Will you speak out or remain silent?

Reference

Frost, P. (2014). Negotiating the gap. Four academics and the dilemma of human biodiversity, Open Behavioral Genetics, June 20

http://openpsych.net/OBG/2014/06/negotiating-the-gap/
https://www.dropbox.com/s/uvtmnssmg5rbwpm/Negotiating%20the%20gap%20-%20Peter%20Fro%20-%20Peter.epub

Bronislaw Malinowski with natives on the Trobriand Islands (1918 - source). Pro-social behavior seems to be a human universal, but is the same true for full empathy?

What is empathy? It has at least three components:

- pro-social behavior, i.e., actions of compassion to help others

- cognitive empathy, i.e., capacity to understand another person's mental state

- affective or emotional empathy, i.e., capacity to respond with the appropriate emotion to another person's mental state (Chakrabarti and Baron-Cohen, 2013)

In their review of the literature, Chakrabarti and Baron-Cohen (2013) conclude that all three components are moderately to highly heritable, although the affective component seems to show the highest heritability (68%). This is in line with Davis et al. (1994), who found significant heritability for the affective facets of empathy (empathic concern and personal distress) but not for non-affective perspective taking.

All three components can vary from one individual to another, although studies to date have focused on pathological variation:

For example, it is suggested that people with psychopathic personality disorder may have intact cognitive empathy (hence being able to deceive others), but impaired affective empathy (hence being able to hurt others), whilst people with autism may show the opposite profile (hence finding the social world confusing because of their deficit in cognitive empathy, but not being over-represented among criminal offenders, having no wish to hurt others, suggesting their affective empathy may be intact)(Chakrabarti and Baron-Cohen, 2013)

People with depression may suffer from too much empathy, i.e., being too sensitive to the needs or distress of others (O'Connor et al., 2007). In short, these disorders seem to be the tail ends of a normal distribution. By focusing on these extremes, we forget that most of the genetic variability in empathy occurs among healthy individuals (Gillberg, 2007).

Using research findings on autism and Asperger syndrome, Chakrabarti and Baron-Cohen (2013) have identified nine candidate genes that seem to promote empathy. They fall into three functional categories: sex-steroid synthesis and metabolism; neural development and connectivity; and social-emotional responsivity. The first category includes the degree to which a fetus is androgenized or estrogenized before birth, as shown by digit ratio (Frost, 2014).

Variation among human populations

If the genes associated with empathy vary among healthy individuals, do they also vary among human populations? This would be expected because populations have differed in their needs for different components of empathy, particularly since hunting and gathering gave way to farming some 10,000 years ago—when genetic change speeded up over a hundred-fold. At that time, humans were no longer adapting to new physical environments. They were adapting to new cultural environments that differed in social structure, in division of labor, in means of subsistence, in norms of conduct, in future time orientation, in degree of sedentary living, and so on. Our ancestors were now reshaping their environments, and these human-made environments were now reshaping them—in other words, gene-culture co-evolution (Hawks et al., 2007).

Humans have been transformed especially by the shift from small bands of hunter-gatherers to larger and more complex groups of farmers and townsfolk. With social relations expanding beyond the circle of close kin, kinship obligations were no longer enough to ensure mutual assistance and stop free riding. There was thus selection for pro-social behavior, i.e., a spontaneous willingness to help not only kin but also non-kin.

Pro-social behavior is attested across a wide range of cultures. It is the subject of a recent book about the nature and limits of empathy in Oceanic cultures. The Banabans of Fiji for instance express the idea of pro-sociality through the term nanoanga, which they normally translate into English by "compassion" or "pity."

[...] compassion is the basis for their capacity to bond socially with others, even compassion to the point of readiness to take strangers into their community. Their empathy therefore relates causally to how they act socially toward others. Here compassion or pity embraces both understanding and fellow feeling: the islanders understand that the stranded mariner is at the end of his strength, which is why they succor him and treat him as one of their own. They understand him because he, like them, is a human being, a person. [...] Thus, for example, when someone passing by a house does not belong to the immediate family of those inside, it is customary to welcome the passer-by by calling out the words mai rin! (Come in!), which carry the implication that food and drink will not be found wanting inside. (Hermann, 2011, p. 31)

This desire to help non-kin is not unconditional. The author notes that prior experiences with an individual in distress can determine whether compassion will be given or withheld. Moreover, Barnabans can "proceed strategically when deciding whether to extend trust to others or to keep thoughts and feelings to themselves" (Hermann, 2011, p. 31). This is not the affective empathy of entering another person's mind to feel his or her pain.

When the Barnabans compare themselves with others, and when by their behavior toward the stranger they show that they understand him and feel with him, they do not, however, equate themselves fully and entirely with him. (Hermann, 2011, p. 32)

Another contributor to the same book writes similarly about the inhabitants of Vanatinai, in the Trobriand Islands.

On the island of Vanatinai, when someone, including an ethnographer, privately asks a trusted confidant, "Why did she/he act like that?""What was she/he thinking?" the common answer, often uttered in tones of puzzlement and despair, or anxiety and fear, expresses one of the islanders' core epistemological principles: "We cannot know their renuanga."Renuanga is a word that refers to a person's inner experiences, both and inseparably thought and emotion.

[...] And their psychic states, their inner thought and feelings, are inherently unknowable. It may never be clear why they were angry or sympathetic, and what caused them to act and influence an event in someone's life [...] (Lepowsky, 2011, p. 44)

In short, Oceanic cultures display hospitality but not full empathy, which would be considered undesirable anyway:

The philosophical principle of personal opacity, the interiority of others' thoughts/feelings (renuanga), is closely bound to the islanders' fierce insistence on personal autonomy, both as cultural ideology and as daily social practice (Lepowsky, 2011, p. 47)

From pro-sociality to full empathy

Whereas pro-sociality is attested across a wide range of cultures, full cognitive/affective empathy is more localized. The difference is like the one we see between shame and guilt. Most cultures primarily use shame to enforce correct behavior, i.e., if other people see you breaking a rule, you feel ashamed and this feeling is reinforced by social disapproval. In contrast, only a minority of cultures—largely those of Northwest Europe—rely primarily on guilt, which operates even when only you see yourself breaking a rule or merely think about breaking a rule (Benedict, 1946; Creighton, 1990).

Northwest Europeans have thus undergone two parallel changes in behavioral control: 1) a shift from pro-sociality to full cognitive/affective empathy; and 2) a shift from shame to guilt. Indeed, full empathy and guilt may be two sides of the same coin. Both are the consequences of a mental model that is used to simulate how another person thinks or feels (an imaginary witness to a wrongful act, a person in distress) and to ensure correct behavior by inducing the appropriate feelings (anguish, pity).

Finally, full empathy and guilt are most adaptive where kinship ties are relatively weak and where rules of correct behavior require a leveling of the playing field between kin and non-kin. This has long been the case in Northwest Europe. There seems to be a longstanding pattern of weak kinship ties west of a line running from Trieste to St. Petersburg, as shown by several culture traits that are rare or absent elsewhere:

- relatively late marriage for men and women

- many people who never marry

- neolocality (children leave the family household to form new households)

- high circulation of non-kin among different households (typically young people sent out as servants) (Hajnal, 1965)

Commonly called the Western European Marriage Pattern, this geographic zone of relatively weak kinship was thought to have arisen after the Black Death of the 14th century. There is now good evidence for its existence before the Black Death and fragmentary evidence going back to 9th century France and even earlier (Hallam, 1985; Seccombe, 1992, p. 94). Historian Alan Macfarlane likewise sees an English tendency toward weaker kinship ties before the 13th century and even during Anglo-Saxon times (Macfarlane, 2012; Macfarlane, 1992, pp. 173-174).

This weak kinship zone may have arisen in prehistory along the coasts of the North Sea and the Baltic, which were once home to a unique Mesolithic culture (Price, 1991). An abundance of marine resources enabled hunter-fisher-gatherers to achieve high population densities by congregating each year in large coastal agglomerations for fishing, sealing, and shellfish collecting. Population densities were comparable in fact to those of farming societies, but unlike the latter there was much "churning" because these agglomerations formed and reformed on a yearly basis. Kinship obligations would have been insufficient to resolve disputes peaceably, to manage shared resources, and to ensure respect for social rules. Initially, peer pressure was probably used to get people to see things from the other person's perspective. Over time, however, the pressure of natural selection would have favored individuals who more readily felt this equivalence of perspectives, the result being a progressive hardwiring of compassion and shame and their gradual transformation into empathy and guilt (Frost, 2013a; Frost, 2013b).

Empathy and guilt are brutally effective ways to enforce social rules. If one disobeys these internal overseers, the result is self-punishment that passes through three stages: anguish, depression and, ultimately, suicidal ideation.

People suffering from depression are looking at both others and themselves with suspicion, often believing whatever they have was obtained by cheating, and that it is more than they deserve. Depressives, burdened by moralistic standards, are harsh evaluators of both themselves and others. The self-punishment meted out by depressives is a common if disturbing symptom; while thinking 'I deserve this', they may engage in altruistic punishment turned upon the self. Just as altruistic punishers experience a neuronally based reward from punishing defectors, despite material costs, depressed patients report a sense of relief upon inflicting self-punishment. Patients who are 'cutters', describe relief from tension after cutting and depressives with suicidal ideation may describe the relief they felt when on the verge of attempting a suicidal action. (O'Connor et al., 2007, p. 67)

This pathology is progressively less common in populations farther south and east, not so much because each stage is less common but rather because depression is much less likely to result from empathic guilt and much less likely to lead to suicide (Stompe et al., 2001). This 3-stage sequence does not seem to be a human universal, at least not to the same extent as in Northwest Europeans, a reality that Frantz Fanon noted when describing clinical depression in Algerians:

French psychiatrists in Algeria found themselves faced with a difficult problem. When treating a melancholic patient, they were accustomed to being afraid of suicide. The melancholic Algerian kills, however. This disease of the moral conscience that is always accompanied by self-accusation and self-destructive tendencies assumes hetero-destructive forms in the Algerian. The melancholic Algerian does not commit suicide. He kills. (Fanon, 1970, pp. 219-220)

References

Benedict, R. (1946 [2005]). The Chrysanthemum and the Sword. Patterns of Japanese Culture, First Mariner Books.

Chakrabarti, B. and S. Baron-Cohen. (2013). Understanding the genetics of empathy and the autistic spectrum, in S. Baron-Cohen, H. Tager-Flusberg, M. Lombardo. (eds). Understanding Other Minds: Perspectives from Developmental Social Neuroscience, Oxford: Oxford University Press.

http://books.google.ca/books?hl=fr&lr=&id=eTdLAAAAQBAJ&oi=fnd&pg=PA326&ots=fHpygaxaMQ&sig=_sJsVgdoe0hc-fFbzaW3GMEslZU#v=onepage&q&f=false

Creighton, M.R. (1990). Revisiting shame and guilt cultures: A forty-year pilgrimage, Ethos, 18, 279-307.

http://sfprg.org/control_mastery/docs/revisitshameguilt.pdf

Davis, M.H., C. Luce, and S.J. Kraus. (1994). The heritability of characteristics associated with dispositional empathy, Journal of Personality, 62, 369-391.

Fanon, F. (1970). Les damnés de la terre, Paris: Maspero.

Frost, P. (2013a). The origins of Northwest European guilt culture, Evo and Proud, December 7

http://evoandproud.blogspot.ca/2013/12/the-origins-of-northwest-european-guilt.html

Frost, P. (2013b). Origins of Northwest European guilt culture, Part II, Evo and Proud, December 14

http://evoandproud.blogspot.ca/2013/12/origins-of-northwest-european-guilt.html

Frost, P. (2014). A pathway to pro-social behavior, Evo and Proud, May 10.

http://evoandproud.blogspot.ca/2014/05/a-pathway-to-pro-social-behavior.html

Gillberg, C. (2007). Non-autism childhood personality disorders, in: T.F.D. Farrow and P.W.R. Woodruff (eds). Empathy in Mental Illness, (pp. 111-125). Cambridge: Cambridge University Press.

Hajnal, J. (1965). European marriage pattern in historical perspective. In D.V. Glass and D.E.C. Eversley (eds). Population in History, Arnold, London.

Hallam, H.E. (1985). Age at first marriage and age at death in the Lincolnshire Fenland, 1252-1478, Population Studies, 39, 55-69.

Hawks, J., E.T. Wang, G.M. Cochran, H.C. Harpending, & R.K. Moyzis. (2007). Recent acceleration of human adaptive evolution. Proceedings of the National Academy of Sciences (USA), 104, 20753-20758.

http://harpending.humanevo.utah.edu/Documents/accel_pnas_submit.pdf

Hermann, E. (2011). Empathy, ethnicity, and the self among the Barnabans in Fiji, in D.W. Hollan, C. J. Throop (eds).The Anthropology of Empathy: Experiencing the Lives of Others in Pacific Societies, (pp. 25-42), New York: Berghahn.

Lepowsky, M. (2011). The boundaries of personhood, the problem of empathy, and "the native's point of view" in the outer islands, in D.W. Hollan, C. J. Throop (eds).The Anthropology of Empathy: Experiencing the Lives of Others in Pacific Societies, (pp. 43-68), New York: Berghahn.

Macfarlane, A. (1992). On individualism, Proceedings of the British Academy, 82, 171-199.

http://www.alanmacfarlane.com/TEXTS/On_Individualism.pdf

Macfarlane, A. (2012). The invention of the modern world. Chapter 8: Family, friendship and population, The Fortnightly Review, Spring-Summer serial

http://fortnightlyreview.co.uk/2012/07/invention-8/

O'Connor, L.E., J.W. Berry, T. Lewis, K. Mulherin, and P.S. Crisostomo. (2007). Empathy and depression: the moral system in overdrive, in: T.F.D. Farrow and P.W.R. Woodruff (eds). Empathy in Mental Illness, (pp. 49-75). Cambridge: Cambridge University Press.

http://www.eparg.org/publications/empathy-chapter-web.pdf

Price, T.D. (1991). The Mesolithic of Northern Europe, Annual Review of Anthropology, 20, 211-233.

http://www.cas.umt.edu/departments/anthropology/courses/anth254/documents/annurev.an.TDouglasPrice1991MseolithicNEurope.pdf

Seccombe, W. (1992). A Millennium of Family Change. Feudalism to Capitalism in Northwestern Europe, London: Verso.

Stompe, T., G. Ortwein-Swoboda, H.R. Chaudhry, A. Friedmann, T. Wenzel, and H. Schanda. (2001). Guilt and depression: a cross-cultural comparative study, Psychopathology, 34, 289-298.

Sigmund Freud (1856-1939) believed that the capacity for guilt varies between individuals and among human populations. He also believed that this variability had, in part, a heritable basis.

Humans are motivated to act correctly by either shame or guilt. We feel shame after acting wrongly in the presence of others. We feel guilt even when no one else sees us acting wrongful or even when we merely think about committing a wrongful act. To varying degrees, all humans seem to have some capacity for both shame and guilt. Most cultures, however, rely primarily on shame and only a minority rely primarily on guilt. In the literature, the distinction between the two is presented as one between non-Western and Western cultures or between collectivistic and individualistic cultures. The capacity for guilt thus seems to be strongest in populations of Northwest European descent.

From the time of Charles Darwin onward, this subject has attracted the interest of several thinkers. How have they explained the origins of shame and guilt?

Charles Darwin

Darwin speculated that shame originated from a universal desire to "save face," which was initially concern about one's personal appearance:

We have seen that in all parts of the world persons who feel shame for some moral delinquency, are apt to avert, bend down, or hide their faces, independently of any thought about their personal appearance. [...] And as the face is the part of the body which is most regarded, it is intelligible that any one ashamed of his personal appearance would desire to conceal this part of his body. The habit, having been thus acquired, would naturally be carried on when shame from strictly moral causes was felt; and it is not easy otherwise to see why under these circumstances there should be a desire to hide the face more than any other part of the body. (Darwin, 1872, p. 123)

Shame, however, is not the same as guilt, and Darwin took care to distinguish between the two when discussing how and why people blush:

With respect to blushing from strictly moral causes, we meet with the same fundamental principle as before, namely, regard for the opinion of others. It is not the conscience which raises a blush, for a man may sincerely regret some slight fault committed in solitude, or he may suffer the deepest remorse for an undetected crime, but he will not blush. "I blush," says Dr. Burgess, "in the presence of my accusers." It is not the sense of guilt, but the thought that others think or know us to be guilty which crimsons the face. A man may feel thoroughly ashamed at having told a small falsehood, without blushing; but if he even suspects that he is detected he will instantly blush, especially if detected by one whom he reveres. (Darwin, 1872, p. 126)

With respect to real shame from moral delinquencies, we can perceive why it is not guilt, but the thought that others think us guilty, which raises a blush. A man reflecting on a crime committed in solitude, and stung by his conscience, does not blush; yet he will blush under the vivid recollection of a detected fault, or of one committed in the presence of others, the degree of blushing being closely related to the feeling of regard for those who have detected, witnessed, or suspected his fault. Breaches of conventional rules of conduct, if they are rigidly insisted on by our equals or superiors, often cause more intense blushes even than a detected crime, and an act which is really criminal, if not blamed by our equals, hardly raises a tinge of colour on our cheeks. (Darwin, 1872, p. 130)

Darwin saw guilt as being not only less universal but also more recent in origin:

The highest possible stage in moral culture is when we recognize that we ought to control our thoughts, and "not even in inmost thought to think again the sins that made the past so pleasant to us." (Darwin, 1936[1888], p. 492)

A few lines further on, he suggested that this kind of mental discipline is "more or less strongly inherited":

There is not the least inherent improbability, as it seems to me, in virtuous tendencies being more or less strongly inherited; for, not to mention the various dispositions and habits transmitted by many of our domestic animals to their offspring, I have heard of authentic cases in which a desire to steal and a tendency to lie appeared to run in families of the upper ranks: and as stealing is a rare crime in the wealthy classes, we can hardly account by accidental coincidence for the tendency occurring in two or three members of the same family. If bad tendencies are transmitted, it is probable that good ones are likewise transmitted. (Darwin, 1936[1888], p. 492)

Has the capacity for guilt been more strongly selected in some human populations than in others? Darwin does not address this question, other than to add:

Except through the principle of the transmission of moral tendencies, we cannot understand the differences believed to exist in this respect between the various races of mankind. (Darwin, 1936[1888], p. 493)

Sigmund Freud

In his work Civilization and Its Discontents (1930), Sigmund Freud argued that guilt was initially a fear of discipline by close kin, particularly one's father. Only later was this fear broadened to include fear of discipline by non-kin, this change being related to the development of larger human communities:

When an attempt is made to widen the community, the same conflict is continued in forms which are dependent on the past; and it is strengthened and results in a further intensification of the sense of guilt. Since civilization obeys an internal erotic impulsion which causes human beings to unite in a closely knit group, it can only achieve this aim through an ever-increasing reinforcement of the sense of guilt. What began in relation to the father is completed in relation to the group. If civilization is a necessary course of development from the family to humanity as a whole, then [...] there is inextricably bound up with it an increase of the sense of guilt, which will perhaps reach heights that the individual finds hard to tolerate. (Freud, 1962, pp. 79-80)

Guilt and shame are two means by which social rules are enforced in large communities where most interactions are no longer with close kin. Shame is enforced by external supervision, i.e., by other people who witness a wrongful act. Guilt is enforced by internal supervision, i.e., by one's conscience, which Freud called the super-ego:

We have also learned how the severity of the super-ego -- the demands of conscience -- is to be understood. It is simply a continuation of the severity of the external authority, to which it has succeeded and which it has in part replaced (Freud, 1962, p. 74)

As the super-ego took over from paternal supervision and discipline, it became not only more important but also more hardwired:

A great change takes place only when the authority is internalized through the establishment of a super-ego. The phenomena of conscience then reach a higher stage. Actually, it is not until now that we should speak of conscience or a sense of guilt. At this point, too, the fear of being found out comes to an end; the distinction, moreover, between doing something bad and wishing to do it disappears entirely, since nothing can be hidden from the super-ego, not even thoughts. It is true that the seriousness of the situation from a real point of view has passed away, for the new authority, the super-ego, has no motive that we know of for ill-treating the ego, with which it is intimately bound up; but genetic influence, which leads to the survival of what is past and has been surmounted, makes itself felt in the fact that fundamentally things remain as they were at the beginning. The super-ego torments the sinful ego with the same feeling of anxiety and is on the watch for opportunities of getting it punished by the external world. (Freud, 1962, p. 72)

The translation is awkward (the original was in German), but he seems to be referring to the heritability of traits that have proven their adaptiveness over time, i.e., "genetic influence, which leads to the survival of what is past and has been surmounted." This heritable component seems to be a capacity, or a willingness, to identify social rules and comply with them, the actual rules being non-innate, i.e., "softwired." This notion of an innate, heritable component comes up again a few pages later:

Experience shows, however, that the severity of the super-ego which a child develops in no way corresponds to the severity of treatment which he has himself met with. The severity of the former seems to be independent of that of the latter. A child who has been very leniently brought up can acquire a very strict conscience. But it would also be wrong to exaggerate this independence; it is not difficult to convince oneself that severity of upbringing does also exert a strong influence on the formation of the child's super-ego. What it amounts to is that in the formation of the super-ego and the emergence of a conscience innate constitutional factors and influences from the real environment act in combination. This is not at all surprising; on the contrary, it is a universal aetiological condition for all such processes. (Freud, 1962, p. 77)

Freud also argued that people differ in their capacity for guilt. In a footnote to the above passage, he explained that the super-ego emerged through "gradual transitions" and thus exists to varying degrees in different people: "[...] it is not merely a question of the existence of the super-ego but of its relative strength and sphere of influence" (Freud, 1962, p. 72). Some individuals are thus extremely guilt-prone:

For the more virtuous a man is, the more severe and distrustful is its [the conscience's] behavior, so that ultimately it is precisely those people who have carried saintliness furthest who reproach themselves with the worst sinfulness. (Freud, 1962, pp. 73-74)

These statements may seem surprising. Didn't Freud believe that neuroses are due to learned inhibitions and that we ought to overcome our inhibitions? Here, however, he argues that both the inhibition of behavior and the expectation of inhibition are instinctual. There has thus been a co-evolution between the internal control mechanism (the super-ego) and human desires (the ego):

The sense of guilt, the harshness of the super-ego, is thus the same things as the severity of the conscience. It is the perception which the ego has of being watched over in this way, the assessment of the tension between its own strivings and the demands of the super-ego. The fear of this critical agency [...] the need for punishment, is an instinctual manifestation on the part of the ego, which has become masochistic under the influence of a sadistic super-ego; it is a portion, that is to say, of the instinct toward internal destruction present in the ego [...] (Freud, 1962, p. 83)

When this control mechanism enters into conflict with human desires, the result is a "conflict between the two primal instincts" (Freud, 1962, p. 84).

We must distinguish between the real Freud and the one of undergrad courses. The latter Freud has become a mouthpiece for beliefs, like rejection of biological determinism and rejection of inhibitions, that did not become dominant until after his death. The real Freud believed that mental and behavioral traits have a substantial heritable basis, as did most scholars of his day. By emphasizing the importance of both nature and nurture, he was in fact taking a very middle-of-the-road position ... for his time. The middle ground would not shift toward environmental determinism until later, with growing interest in the findings of Ivan Petrovich Pavlov and subsequent efforts by the Boasian school of anthropology to explain human behavior in terms of cultural conditioning.

To be continued

References

Darwin, C. (1936) [1888]. The Descent of Man and Selection in relation to Sex. reprint of 2nd ed., The Modern Library, New York: Random House.

Darwin, C. (1872). The Expression of the Emotions in Man and Animals, London: Murray.

Freud, S. (1962[1930]). Civilization and Its Discontents, New York: W.W. Norton

Inuit meat cache, Kazan River (source: Library and Archives Canada / PA-101294). Because of their high meat diet, hunters produce more body heat than farmers do. Natural selection has thus favored certain mtDNA sequences over others in humans with this profile of heat production. A change in selection pressure may therefore explain, at least in part, the genetic divide between late hunter-gatherers and early farmers in Europe.

Who were the ancestors of present-day Europeans? The hunter-gatherers of the Paleolithic and the Mesolithic? Or the Neolithic farmers who began to spread out of the Middle East some 10,000 years ago?

This debate has teetered back and forth for the past thirty years. On the basis of various genetic polymorphisms, L.L. Cavalli-Sforza and his students argued that Europeans are largely descended from Middle Eastern farmers (Ammerman and Cavalli-Sforza, 1984; Cavalli-Sforza et al., 1994). On the basis of mtDNA and Y chromosomal data, two other research teams, one led by Martin Richards and the other by Ornella Semino, maintained that the European gene pool is over 75% of native hunter-gatherer origin (Richards et al., 2000; Semino et al., 2000). If we look only at the present-day gene pool, Europeans seem far too differentiated to be the descendants of Neolithic farmers from the Middle East.

Over the last few years, new evidence has swung the debate back to the model of population replacement. By retrieving DNA from ancient skeletal remains, we can now compare the latest hunter-gatherers with the earliest farmers, and what we see is a sharp genetic divide between the two (Bramanti et al., 2009). The farmers seem to have been immigrants who replaced the hunter-gatherers. This is direct evidence, so what more is there to say? Facts are facts.

Yet there is always more to say. Facts may be illusory or, if real, wrongly interpreted. For one thing, wherever we have a fairly continuous time series of ancient DNA, the genetic divide no longer appears between the latest hunter-gatherers and the earliest farmers. It appears between the earliest farmers and somewhat later farmers. This is particularly so when we examine haplogroup U lineages, whose disappearance is widely seen as evidence for population replacement. According to a study of 92 Danish remains, these lineages remained common after the Neolithic and reached their current low prevalence only during the Early Iron Age (Melchior et al., 2010).

If this genetic divide is not solely due to population replacement, what else might be responsible? Mishmar et al. (2003) were the first to suggest natural selection:

Thus, extensive global population studies have shown that there are striking differences in the nature of the mtDNAs found in different geographic regions. Previously, these marked differences in mtDNA haplogroup distribution were attributed to founder effects, specifically the colonizing of new geographic regions by only a few immigrants that contributed a limited number of mtDNAs. However, this model is difficult to reconcile with the fact that northeastern Africa harbors all of the African-specific mtDNA lineages as well as the progenitors of the Eurasia radiation, yet only two mtDNA lineages (macrohaplogroups M and N) left northeastern Africa to colonize all of Eurasia (1, 2) and also that there is a striking discontinuity in the frequency of haplogroups A, C, D, and G between central Asia and Siberia, regions that are contiguous over thousands of kilometers. Rather than Eurasia and Siberia being colonized by a limited number of founders, it seems more likely that environmental factors enriched for certain mtDNA lineages as humans moved to the more northern latitudes.

[...] We now hypothesize that natural selection may have influenced the regional differences between mtDNA lineages. This hypothesis is supported by our demonstration of striking differences in the ratio of nonsynonymous (nsyn)/synonymous (syn) nucleotide changes in mtDNA genes between geographic regions in different latitudes. We speculate that these differences may reflect the ancient adaptation of our ancestors to increasingly colder climates as Homo sapiens migrated out of Africa and into Europe and northeastern Asia.

This hypothesis has since received support from Balloux et al. (2009):

We show that populations living in colder environments have lower mitochondrial diversity and that the genetic differentiation between pairs of populations correlates with difference in temperature. These associations were unique to mtDNA; we could not find a similar pattern in any other genetic marker. We were able to identify two correlated non-synonymous point mutations in the ND₃ and ATP6 genes characterized by a clear association with temperature, which appear to be plausible targets of natural selection producing the association with climate. The same mutations have been previously shown to be associated with variation in mitochondrial pH and calcium dynamics. Our results indicate that natural selection mediated by climate has contributed to shape the current distribution of mtDNA sequences in humans.

Humans have to adapt to two sources of warmth: climate and internal body heat, which in turn varies with lifestyle and diet. Diet in particular results in different patterns of body heat production between hunter-gatherers and farmers, as explained by Speth (1983):

One aspect of protein metabolism relevant to this issue concerns the high "specific dynamic action" (SDA) of protein ingestion. The SDA of food refers to the rise in metabolism or heat production (diet-induced thermogenesis) resulting from the ingestion of food [...] The SDA of a diet consisting largely of fat is about 6- 14%, while that of a diet high in carbohydrates is about 6%. In striking contrast, the SDA of a diet consisting almost entirely of protein may be as high as 30%; or, in other words, for every 100 calories of protein ingested, up to 30 calories are needed to compensate for the increase in metabolism. Thus, persons whose diets are high in protein experience higher metabolic rates than those whose diets are composed largely of carbohydrate. For example, members of Eskimo populations, at least 90% of whose caloric needs were traditionally met by meat and fat (cf. Draper 1980:263; Hoygaard 1941), had basal metabolic rates 13 to 33% above the DuBois standard, which is based on the metabolic rates of populations consuming western diets (Itoh 1980:285).

Conclusion

Before ancient DNA became available, the prehistory of populations had to be inferred. The age of a genetic lineage was inferred from the degree of differentiation divided by the mutation rate. Since both variables could be known only approximately, the time depths of Europe's genetic lineages were likewise known only approximately.

Ancient DNA seems to promise a clearer picture because the only source of uncertainty is the age of the skeletal material. Unfortunately, this new method is more sensitive to uncertainty from another source: natural selection. Late hunter-gatherers and early farmers had to adapt to different environments. There certainly was a genetic divide between the two, but did it result from differences in origin or from differences in natural selection?

Natural selection distorts the picture if either method is used, since both assume that mtDNA is selectively neutral. The distortion is more serious, however, with the new method, which assumes selective neutrality across the genetic divide between late hunter-gatherers and early farmers—the very moment in prehistory when this assumption is most likely to fail. The old method assumes selective neutrality throughout the entire time depth of Europe’s genetic lineages—an assumption that may indeed be true over most of that time.

Even if the lineage has no selective value in and of itself, natural selection can still distort the picture. This is especially so for mtDNA:

Selection can change allele frequency even at a locus not responsible for fitness differences. Because there is little or no recombination in mitochondrial DNA, selection at one nucleotide affects the frequencies of all other variable nucleotides for the whole molecule. Selection on the nuclear genome, particularly nuclear-encoded proteins that are imported into the mitochondrion and X-linked markers that can have a high effective linkage to mtDNA, can also cause changes in the frequencies of mtDNA haplotypes. Equally importantly, selection on any other cytoplasmically inherited traits will directly affect the frequencies of mtDNA. (Ballard and Whitlock, 2004)

This is less of a problem with nuclear DNA because of recombination, but the problem remains if the presumably neutral gene is close to another gene of high selective value.

In raising these points, I am not trying to argue that Middle Eastern farmers made no contribution to the European gene pool. There is good archaeological evidence of these farmers pushing up the Danube and into central Europe. Elsewhere, however, the evidence for population replacement becomes weaker and the evidence for continuity correspondingly stronger. This is the conclusion that Zvelebil and Dolukhanov (1991) make with respect to northern and eastern Europe:

The transition to farming occurred very slowly and took a long time to complete, the whole process lasting 1500-4000 years. In the far north and northeast of Europe, the process was never completed. [...] Local hunter-gatherer societies played a significant role in the transition. There is strong evidence for continuity in material culture in most regions throughout the transition. Although this neither proves nor disproves the case for population movement associated with the transition (small groups of people could have migrated, leaving little or no trace in the archaeological record), such evidence does not support the colonization model for the transition to farming and it does indicate that local hunter-gatherer traditions were passed on from generation to generation during the long period of the adoption of farming.

And yet the advent of farming brought massive genetic change to northern and eastern Europe, including widespread decline of haplogroup U—the sort of change that is supposed to mean massive population replacement. Since farming began to spread to this region only 6,000 years ago, even later among the Finnish and Baltic peoples, there is only a very narrow time frame in which northern and eastern Europeans could have evolved their characteristic physical appearance, assuming of course that population replacement had actually happened.

Even in central Europe, where population replacement is well documented, we are still unsure whether it was permanent or temporary. Indeed, we see evidence of the replacers being later replaced, perhaps by natives who had never disappeared from the vicinity of the farming settlements (Haak et al., 2005;Rowley-Conwy, 2011).

References

Ammerman, A.J. and L.L. Cavalli-Sforza. (1984). The Neolithic Transition and the Genetics of Populations in Europe, New Jersey: Princeton University Press.

Ballard, J.W.O. and M.C. Whitlock. (2004). The incomplete natural history of mitochondria, Molecular Ecology, 13, 729-744.

http://dna.ac/filogeografia/PDFs/Ballard%26Whitlock_04_MTrev.pdf

Balloux F., L.J. Handley, T. Jombart, H. Liu, and A. Manica (2009). Climate shaped the worldwide distribution of human mitochondrial DNA sequence variation. Proceedings. Biological Sciences, 276(1672), 3447-55.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2817182/?tool=pmcentrez

Bramanti, B., M. G. Thomas, W. Haak, M. Unterlaender, P. Jores, K. Tambets, I. Antanaitis-Jacobs, M.N. Haidle, R. Jankauskas, C.-J. Kind, F. Lueth, T. Terberger, J. Hiller, S. Matsumura, P. Forster, and J. Burger. (2009). Genetic discontinuity between local hunter-gatherers and Central Europe's first farmers, Science, 326 (5949), 137-140.

http://jsarf.free.fr/palanthsci/Europe's%20First%20Farmers%20Were%20Immigrants.pdf

Cavalli-Sforza, L.L., P. Menozzi, and A. Piazza. (1994). The History and Geography of Human Genes, New Jersey: Princeton University Press.

Haak, W., P. Forster, B. Bramanti, S. Matsumura, G. Brandt, M. Tänzer, R. Villems, C. Renfrew, D. Gronenborn, K.W. Alt, and J. Burger. (2005). Ancient DNA from the first European farmers in 7500-year-old Neolithic sites, Science, 310 (5750), 1016-1018.

http://www.sciencemag.org/content/310/5750/1016.short

Melchior, L., N. Lynnerup, H.R. Siegismund, T. Kivisild, J. Dissing. (2010). Genetic diversity among ancient Nordic populations, PLoS ONE, 5(7): e11898

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0011898#pone-0011898-g002

Mishmar, D., E. Ruiz-Pesini, P. Golik, V. Macaulay, A.G. Clark, S. Hosseini, M. Brandon, K. Easley, E. Chen, M.D. Brown, R.I. Sukernik, A. Olckers, and D.C. Wallace. (2003). Natural selection shaped regional mtDNA variation in humans, Proceedings of the National Academy of Sciences (USA), 100 (1), 171-176.

http://www.pnas.org/content/100/1/171.full

Richards, M., V. Macaulay, E. Hickey, E. Vega, B. Sykes, et al. (2000). Tracing European founder lineages in the Near Eastern mtDNA pool, American Journal of Human Genetics, 67, 1251-1276.

http://www.sciencedirect.com/science/article/pii/S0002929707629541

Rowley-Conwy, P. (2011). Westward ho! The spread of agriculturalism from Central Europe to the Atlantic, Current Anthropology, 52 (S4), S431-S451.

http://arkeobotanika.pbworks.com/w/file/fetch/48307263/Rowley-Conwy%2011%20CA%20Farming%20westward.pdf

Semino, O., G. Passarino, P.J. Oefner, A.A. Lin, S. Arbuzova, et al. (2000). The genetic legacy of Paleolithic Homo sapiens sapiens in extant Europeans: A Y chromosome perspective, Science, 290, 1155-1159.

http://fboekelo.tripod.com/boekelo/GP/semino.pdf

Speth, J.D. (1983). Energy source, protein metabolism, and hunter-gatherer subsistence strategies, Journal of Anthropological Archaeology, 2, 1-31.

http://faculty.ksu.edu.sa/archaeology/Publications/Hearths/Energy%20source,%20protein%20metabolism,%20and%20hunter-gatherer%20subsistence%20strategies.pdf

Zvelebil, M. and P. Dolukhanov. (1991). The transition to farming in Eastern and Northern Europe, Journal of World Prehistory, 5, 233-278.

http://link.springer.com/article/10.1007/BF00974991

The anthropologist Franz Boas is remembered for moving the social sciences away from genetic determinism and toward environmental determinism. In reality, he felt that genes do contribute substantially to mental and behavioral differences ... and not just between individuals.

Most of us identify with certain great teachers of the past: Christ, Marx, Freud … Though long dead, they still influence us and we like to think that their teachings have come down to us intact. We know what they believed … or so we like to think. This raises a problem when we find discrepancies. Jesus was so humble that he resented being called good, since only God is truly good. But then ...

Often, however, the discrepancies remain unknown. They develop too gradually for the average person to notice and are most obvious to those who least want to point them out, i.e., the successors of the great teacher. Of course, the great teacher is no longer around to set things straight.

This has happened to many belief-systems. In my last post, I discussed how the real Sigmund Freud differed significantly from the one we know. The same is true for Franz Boas (1858-1942), whose school of anthropology is as much a product of his immediate disciples—Margaret Mead and Ruth Benedict—as of Boas himself.

Today, Boas is remembered as the man who moved the social sciences away from genetic determinism and toward environmental determinism. His Wikipedia entry states:

Boas was one of the most prominent opponents of the then popular ideologies of scientific racism, the idea that race is a biological concept and that human behavior is best understood through the typology of biological characteristics. [...] Boas also worked to demonstrate that differences in human behavior are not primarily determined by innate biological dispositions, but are largely the result of cultural differences acquired through social learning.

In reality, he felt that genes do contribute substantially to mental and behavioral differences ... and not just between individuals. This is apparent in a speech he gave in 1894 under the title "Human Faculty as Determined by Race."

It does not seem probable that the minds of races which show variations in their anatomical structure should act in exactly the same manner. Differences of structure must be accompanied by differences of function, physiological as well as psychological; and, as we found clear evidence of difference in structure between the races, so we must anticipate that differences in mental characteristics will be found. [...] As all structural differences are quantitative, we must expect to find mental differences to be of the same description, and as we found the variations in structure to overlap, so that many forms are common to individuals of all races, so we may expect that many individuals will not differ in regard to their faculty, while a statistical inquiry embracing the whole races would reveal certain differences. Furthermore, as certain anatomical traits are found to be hereditary in certain families and hence in tribes and perhaps even in peoples, in the same manner mental traits characterize certain families and may prevail among tribes. It seems, however, an impossible undertaking to separate in a satisfactory manner the social and the hereditary features. Galton's attempt to establish the laws of hereditary genius points out a way of treatment for these questions which will prove useful in so far as it opens a method of determining the influence of heredity upon mental qualities (Boas, 1974, p. 239)

We have shown that the anatomical evidence is such, that we may expect to find the races not equally gifted. While we have no right to consider one more ape-like than the other, the differences are such that some have probably greater mental vigor than others. The variations are, however, such that we may expect many individuals of all races to be equally gifted, while the number of men and women of higher ability will differ.(Boas, 1974, p. 242)

When discussing brain size, Boaz merely pointed to the overlap among racial groups:

We find that 50 per cent of all whites have a capacity of the skull greater than 1550 cc., while 27 per cent of the negroes and 32 per cent of the Melanesians have capacities above this value. We might, therefore, anticipate a lack of men of high genius, but should not anticipate any great lack of faculty among the great mass of negroes living among whites and enjoying the advantages of the leadership of the best men of that race. (Boas, 1974, pp. 233-234)

He did add that "mental ability certainly does not depend upon the size of the brain alone." He then argued, quoting an authority, that the encephalon and the cortex develop to a greater degree in whites, especially after puberty:

When we compare the capacity for education between the lower and higher races, we find that the great point of divergence is at adolescence and the inference is fairly good that we shall not find in the brains of the lower races the post-pubertal growth in the cortex to which I have just alluded. (Boas, 1974, p. 234)

Boas would return to this topic, such as in this 1908 speech on "Race Problems in America":

I do not believe that the negro is, in his physical and mental make-up, the same as the European. The anatomical differences are so great that corresponding mental differences are plausible. There may exist differences in character and in the direction of specific aptitudes. There is, however, no proof whatever that these differences signify any appreciable degree of inferiority of the negro, notwithstanding the slightly inferior size, and perhaps lesser complexity of structure, of his brain; for these racial differences are much less than the range of variation found in either race considered by itself.(Boas, 1974, pp. 328-329)

All of these remarks must be judged in context. Boaz was trying to stake out a reasonable middle ground in opposition to the view that human races differ not only in degree but also in kind. There is also little doubt about his opposition to racial discrimination, which he felt was holding back many capable African Americans.

But he did not feel that equality of opportunity would lead to equality of results. This was the middle ground he defended, and it is far removed from today's middle ground. The two don't even overlap. What happened between then and now?

Something critical seems to have happened in the late 1930s. When Boas prepared the second edition of The Mind of Primitive Man (1938), he removed his earlier racialist statements. The reason was likely geopolitical. As a Jewish American seeing the rise of Nazi Germany, he may have felt that the fight against anti-Semitism would require a united front against all forms of “racism”—a word just starting to enter common use and initially a synonym for Nazism.

Boas died in 1942 and the leadership of his school of anthropology fell to Ruth Benedict and Margaret Mead. With the end of the war, both of them wished to pursue and even escalate the fight against racism. Escalation was favored by several aspects of the postwar era: lingering fears of a revival of anti-Semitism, competition between the two power blocs for the hearts and minds of the Third World, and an almost utopian desire to rebuild society—be it through socialism, social democracy, or new liberalism … In all this, we are no longer in the realm of science, let alone anthropology.

Boas had sought to strike a new balance between nature and nurture in the study of Man. The war intervened, however, and Boasian anthropology was conscripted to fight not only the Axis but also racism in any form. Today, three-quarters of a century later, we’re still fighting that war.

References

Boas, F. (1974). A Franz Boas Reader. The Shaping of American Anthropology, 1883-1911, G.W. Stocking Jr. (ed.), Chicago: The University of Chicago Press.

Wikipedia (2014). Franz Boas

http://en.wikipedia.org/wiki/Franz_Boas

Licensed under public domain via Wikimedia Commons

Ruth Benedict (1887-1948), much more than Franz Boas, would define the aims of Boasian anthropology for postwar America.

When Franz Boas died in 1942, the leadership of his school of anthropology passed to Ruth Benedict and not to Margaret Mead. This was partly because Benedict was the older of the two and partly because her book Patterns of Culture (1934) had already assumed a key role in defining Boasian anthropology.

The word "define" may surprise some readers. Wasn't Boas a Boasian? Not really. For most of his life he believed that human populations differ innately in their mental makeup. He was a liberal on race issues only in the sense that he considered these differences to be statistical and, hence, no excuse for systematic discrimination. Every population has capable individuals who should be given a chance to rise to the limits of their potential.

He changed his mind very late in life when external events convinced him of the need to fight "racism," at that time a synonym for extreme nationalism in general and Nazism in particular. In 1938, he removed earlier racialist statements from his second edition of The Mind of Primitive Man, and the next year Ruth Benedict wrote Race: Science and Politics to show that racism was more than a Nazi aberration, being in fact an ingrained feature of American life. Both of them saw the coming European conflict as part of a larger war.

This is one reason why the war on racism did not end in 1945. Other reasons included a fear that extreme nationalism would lead to a second Hitler and a Third World War. How and why was never clear, but the fear was real. The two power blocs were also competing for the hearts and minds of emerging nations in Asia and Africa, and in this competition the West felt handicapped. How could it win while defining itself as white and Christian? The West thus redefined itself in universal terms and became just as committed as the Eastern bloc to converting the world to its way of life. Finally, the rhetoric of postwar reconstruction reached into all areas of life, even in countries like the U.S. that had emerged unscathed from the conflict. This cultural reconstruction was a logical outcome of the Second World War, which had discredited not just Nazism but also nationalism in general, thereby leaving only right-wing globalism or left-wing globalism. Ironically, this cultural change was weaker in the communist world, where people would remain more conservative in their forms of sociality.

Ruth Benedict backed this change. She felt that America should stop favoring a specific cultural tradition and instead use its educational system to promote diversity. To bring this about, she had to reassure people that a journey through such uncharted waters would not founder on the shoals of unchanging human nature. This fear had been addressed in Patterns of Culture (1934). Inspired by Pavlov’s research on conditioned reflexes, she argued that people are conditioned by their culture to think, feel, and behave in a particular way. This pattern assumes over time such a rigid form that even a student of anthropology will assume it to be innate:

He does not reckon with the fact of other social arrangements where all the factors, it may be, are differently arranged. He does not reckon, that is, with cultural conditioning. He sees the trait he is studying as having known and inevitable manifestations, and he projects these as absolute because they are all the materials he has to think with. He identifies local attitudes of the 1930’s with Human Nature […] (Benedict, 1989, p. 9)

She argued that such behavioral traits cannot be innate, since they assume different patterns in different human populations and in different time periods of a single population. Our potential for social change is thus greater than what we imagine, being limited only by the range of behavior that exists across all societies. Because we underestimate this potential, we resist social change on the grounds that it would violate a nonexistent human nature:

The resistance is in large measure a result of our misunderstanding of cultural conventions, and especially an exaltation of those that happen to belong to our nation and decade. A very little acquaintance with other conventions, and a knowledge of how various these may be, would do much to promote a rational social order. (Benedict, 1989, p. 10)

In contradistinction to Boas, who believed that human populations differ innately in various mental and behavioral traits, she argued that cultural evolution had long ago replaced genetic evolution:

Man is not committed in detail by his biological constitution to any particular variety of behaviour. The great diversity of social solutions that man has worked out in different cultures in regard to mating, for example, or trade, are all equally possible on the basis of his original endowment. Culture is not a biologically transmitted complex. (Benedict, 1989, p. 14)

In short, humans have turned the tables on evolution. Instead of being changed by their environment via natural selection, they redesign it with the tools provided by their culture. To a large degree, humans create their own environment:

The human animal does not, like the bear, grow himself a polar coat in order to adapt himself, after many generations, to the Arctic. He learns to sew himself a coat and put up a snow house. From all we can learn of the history of intelligence in pre-human as well as human societies, this plasticity has been the soil in which human progress began and in which it has maintained itself. [...] The human cultural heritage, for better or for worse, is not biologically transmitted. (Benedict, 1989, p. 14)

Since human nature is everywhere the same, whatever works in any other culture ought to work in America’s, and this greater diversity should pose no serious problem. This argument would eventually be topped off by American can-doism: if other cultures can cope with some diversity, we can do even better!

Much more deviation is allowed to the individual in some cultures than in others, and those in which much is allowed cannot be shown to suffer from their peculiarity. It is probable that social orders of the future will carry this tolerance and encouragement of individual difference much further than any cultures of which we have experience. (Benedict, 1989, p. 273)

Such social change would be resisted by Middletown—originally a pseudonym for Muncie, Indiana in two sociological studies, and later a synonym for whitebread small-town America.

The American tendency at the present time leans so far to the opposite extreme that it is not easy for us to picture the changes that such an attitude would bring about. Middletown is a typical example of our usual urban fear of seeming in however slight an act different from our neighbours. Eccentricity is more feared than parasitism. Every sacrifice of time and tranquillity is made in order that no one in the family may have any taint of nonconformity attached to him. Children in school make their great tragedies out of not wearing a certain kind of stockings, not joining a certain dancing-class, not driving a certain car. The fear of being different is the dominating motivation recorded in Middletown. (Benedict, 1989, p. 273)

Conclusion

Ruth Benedict wrote well, so well that any flaws are easily missed. Much of her reasoning revolved around the concept of cultural conditioning. Just as a dog will salivate on hearing the tinkling of a bell, if associated with food, so people will come to respond unthinkingly and in the same way to a situation that occurs over and over again. Such behavior may seem innate, yet it isn't. This part of her reasoning is true, but it is also true that natural selection tends to hardwire any recurring behavioral response. Mental plasticity has a downside, particularly the risks of responding incorrectly to a situation when one is still learning. It's better to get things right the first time. In sum, conditioned reflexes and innate reflexes both have their place, and one doesn't preclude the other ... for either dogs or humans.

Benedict seems on firmer ground in saying that humans are uniquely able to change the world around themselves. Instead of having to adapt biologically to our environment, we can invent ways to make it adapt to us. It's this manmade environment—our culture—that does the evolving, not our genes. This view used to be widely accepted in anthropology and has been proven false only recently. We now know that cultural evolution actually caused genetic evolution to accelerate. At least 7% of the human genome has changed over the last 40,000 years, and most of that change seems to be squeezed into the last 10,000, when the pace of genetic change was more than a hundred-fold higher (Hawks et al., 2007). By that time, humans were no longer adapting to new physical environments; they were adapting to new culturalenvironments. Far from slowing down genetic evolution, culture has speeded it up by greatly diversifying the range of circumstances we must adapt to.

Benedict was right in foreseeing a time when tolerance would become a virtue. Yet, strangely enough, Middletown America is no more tolerant today than it was in her time. Americans are simply obeying a new set of rules, whose first commandment is now "Thou shalt not be intolerant." People are still fearful of being different from their neighbours. It's just that the fears have another basis. People are still insulted for being different. It's just that the insults have changed. "Filthy pervert" has given way to "Dirty homophobe." Mistrust of the stranger has been replaced by mistrust of those who are not inclusive. Pierre-André Taguieff has described this new conformity in France:

[...] over the last thirty years of the 20th century, the word "racism" became an insult in everyday language ("racist!""dirty racist!"), an insult derived from the racist insult par excellence ("dirty nigger!", "dirty Jew!"), and given a symbolic illegitimating power as strong as the political insult "fascist!" or "dirty fascist!". To say an individual is "racist" is to stigmatize him, to assign him to a heinous category, and to abuse him verbally [...] The "racist" individual is thus expelled from the realm of common humanity and excluded from the circle of humans who are deemed respectable by virtue of their intrinsic worth. Through a symbolic act that antiracist sociologists denounce as a way of "racializing" the Other, the "racist" is in turn and in return categorized as an "unworthy" being, indeed as an "unworthy" being par excellence. For, as people say, what can be worse than racism? (Taguieff, 2013, p. 1528)

It's hard to believe that the sin of racism did not yet exist in Ruth Benedict's day. The word itself was just starting to enter common use. At most, there was a growing movement for people to be more tolerant, and even that movement was very limited in its aims. "Tolerance" had a much less radical meaning.

Interestingly, Benedict did touch on the reason for Middletown's intolerance. In her book, The Chrysanthemum and the Sword (1946), she explained that human cultures enforce social rules by means of shame or guilt. You feel ashamed if your wrongdoing is seen by another person. In contrast, you feel guilty even if nobody else has seen it, or even if you merely think about doing wrong. Although all humans have some capacity for both shame and guilt, the relative importance of one or the other varies considerably among individuals and among human populations. "Shame cultures" greatly outnumber "guilt cultures," which are essentially limited to societies of Northwest European origin, like Middletown.

But how does a guilt culture survive? If a few individuals feel no guilt as long as no one is looking, they will have an edge over those who do. Over time, they will proliferate at the expense of the guilt-prone, and the guilt culture will become a shame culture. It seems that this outcome does not happen because the guilt-prone are always looking for signs of deviancy in other individuals, however trifling it may seem. We have here the "broken windows" theory of law enforcement: if a person tends to break any rule, however minor, he or she will likely break a major one, since the psychological barrier against wrongdoing is similar in both cases. The guilt-prone will judge such people to be morally worthless and will ultimately expel them from the community. Intolerance is the price we pay for the efficiency of a guilt culture.

Today, this mechanism has been turned upon itself. The new social rule—intolerance of intolerance—will, over the not so long term, dissolve the mental makeup that makes a guilt culture possible. Benedict did not foresee this outcome in her own time. Middletown was too set in its ways, too monolithic, too well entrenched. At most, one could hope for a little more leeway for the socially deviant. A few bohemians here, a few oddballs there ...

Ruth Benedict saw Middletown as a difficult case, particularly its extreme guilt culture, and she drew on the language of education and psychotherapy to frame this difficulty in terms of long-term treatment:

[…] there can be no reasonable doubt that one of the most effective ways in which to deal with the staggering burden of psychopathic tragedies in America at the present time is by means of an educational program which fosters tolerance in society and a kind of self-respect and independence that is foreign to Middletown and our urban traditions. (Benedict, 1989, pp. 273-274)

They [the Puritans] were the voice of God. Yet to a modern observer it is they, not the confused and tormented women they put to death as witches, who were the psychoneurotics of Puritan New England. A sense of guilt as extreme as they portrayed and demanded both in their own conversion experiences and in those of their converts is found in a slightly saner civilization only in institutions for mental diseases. (Benedict, 1989, p. 276)

By the time of her death in 1948, Boasian anthropology had become fully mobilized for the war on racism. This mobilization had begun in response to the rise of Nazi Germany but was soon extended to a much larger enemy that included America itself, as seen in the increasingly radical meanings of “racism” and “tolerance.” Only a determined, long-term effort would bring this enemy to heel.

References

Benedict, R. (1989 [1934]). Patterns of Culture, Boston: Houghton Mifflin.

Benedict, R. (2005 [1946]). The Chrysanthemum and the Sword. Patterns of Japanese Culture, First Mariner Books.

Hawks, J., E.T. Wang, G.M. Cochran, H.C. Harpending, & R.K. Moyzis. (2007). Recent acceleration of human adaptive evolution. Proceedings of the National Academy of Sciences (USA), 104, 20753-20758.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2410101/

Taguieff, P-A. (2013). Dictionnaire historique et critique du racisme, Paris: PUF.

When geneticist Davide Piffer examined IQ-enhancing alleles at seven different genes, he found that their average prevalence differed among human populations, being highest in East Asians and lowest in Mbuti Pygmies (photo used with author's approval)

My weekly posts are now appearing on The Unz Review (http://www.unz.com/). By accepting Ron's invitation, I hope to reach a bigger audience and bring myself closer to other writers in the area of human biodiversity. When people work together, or simply alongside each other, minor differences can be ironed out and major differences narrowed or at least accepted good-naturedly. One thing I've learned is that academic debate can leave a legacy of hurt feelings. The impersonal can become personal, partly because people feel attached to their views and partly because views themselves can have personal impacts.

Working together also creates synergy. It becomes easier to identify research priorities, contact interested researchers, and end up with publishable findings. At present, most HBD research involves trawling through the literature and offering new interpretations. That's fine, but we need lab work as well. This point came up in a 2006 interview with geneticist Bruce Lahn:

A lot of researchers studying human population genetics and evolution are strictly data miners (i.e., they generate/publish no original data). There are limitations to such an approach, as it depends on the available data and prevents certain analyses from being performed. Do you expect to see more research groups turning into pure data mining labs in the future? Or will there still be a place for independent labs generating their own data (for example, resequencing a gene in multiple individuals to study the polymorphism)?

Given the explosion of genomic data in the last decade or so, which shows no sign of slowing down any time soon, there is likely to be a proliferation of pure data miners just because there is a niche for them. But I suspect that many interesting findings will still require the combination of data mining and wet experiments to provide key pieces of data not already available in public databases. In this regard, labs that can do both data mining and wet experiments can have an advantage over labs that can only do data mining. (Gene Expression, 2006)

Lab work will probably have to be offshored, not because it's cheaper to do elsewhere but because the "free world" is no longer the best place for unimpeded scientific inquiry. A Hong Kong team is conducting a large-scale investigation into the genetics of intelligence, and nothing comparable is being done in either North America or Western Europe. Cost isn't the reason.

A few suggestions for research:

Human variation in IQ-enhancing alleles

We know that human intellectual capacity has risen through small incremental changes at very many genes, probably hundreds if not thousands. Have these changes been the same in all populations?

Davide Piffer (2013) has tried to answer this question by using a small subset of these genes. He began with seven SNPs whose different alleles are associated with differences in performance on PISA or IQ tests. Then, for fifty human populations, he looked up the prevalence of each allele that seems to increase performance. Finally, for each population, he calculated the average prevalence of these alleles at all seven genes.

The average prevalence was 39% among East Asians, 36% among Europeans, 32% among Amerindians, 24% among Melanesians and Papuan-New Guineans, and 16% among sub-Saharan Africans. The lowest scores were among San Bushmen (6%) and Mbuti Pygmies (5%). A related finding is that all but one of the alleles are specific to humans and not shared with ancestral primates.

Yes, he was using a small subset of genes that influence intellectual capacity. But you don't need a big number to get the big picture. If you dip your hand into a barrel of differently colored jelly beans, the colors you see in your hand will match well enough what's in the barrel. In any case, if the same trend holds up with a subset of 50 or so genes, it will be hard to say it's all due to chance.

Interaction between age and intellectual capacity

These population differences seem to widen after puberty, as Franz Boas noted a century ago (Boas, 1974, p. 234). It may be that general intelligence was largely confined to early childhood in ancestral humans, as a means to integrate information during the time of life when children become familiar with their surroundings. With increasing age, and familiarity, this learning capacity would shut down. When modern humans began to enter environments that had higher cognitive demands, natural selection may have favored retention of general intelligence in adulthood, just as it favored retention of the capacity to digest lactose wherever adults raised dairy cattle and drank milk.

After doing a principal component analysis on covariance between the above IQ-enhancing alleles and performance on IQ and Pisa tests, Piffer (2013) was able to identify three alleles that show the highest loading on the first component. Ward et al. (2014) have found that possession of these three alleles correlates with educational performance of 13 to 14 year old children. We now have a tool to measure the interaction between genes and age in the development of intellectual capacity, particularly during the critical period extending from pre-puberty to early adulthood.

Convergent evolution

Some human populations seem to have arrived at similar outcomes through different evolutionary trajectories. East Asians, for instance, resemble Western Europeans in their level of societal development, but this similar outcome has been achieved through a different mental and behavioral package, specifically lower levels of guilt and empathy with correspondingly higher levels of shame and prosocial behavior. In short, East Asians tend to enforce social rules more by external mediation (e.g., shaming, peer pressure, family discipline) than by internal control (e.g., guilt, empathy).

This difference probably reflects a mix of learned and innate predispositions, since natural selection favors whatever works, regardless of how hardwired it may or may not be. To the extent that these predispositions are hardwired, East Asians may be less able to cope with the sort of aloneness, anonymity, and individualism we take for granted.

It would be easy enough to study the neurological effects of social isolation on East Asians, and there is already suggestive evidence that such effects include unusual outbursts of psychotic behavior. It would be harder, however, to determine whether this malfunctioning has a heritable component.

Microcephalin - Why does its Eurasian allele increase brain volume?

Almost a decade ago, Bruce Lahn was among those who discovered that a gene involved in brain growth, Microcephalin, continued to evolve after modern humans had spread out of Africa. Its most recent allele arose some 37,000 years ago in Eurasia and is still largely confined to native Eurasians and Amerindians (Evans et al., 2005). Interest in this finding evaporated when no significant correlation was found between the Eurasian allele and higher scores on IQ tests (Mekel-Bobrov et al, 2007; Rushton et al., 2007). Nonetheless, a later study showed that this allele correlates with increased brain volume (Montgomery and Mundy, 2010).

The time of origin corresponds to the entry of modern humans into seasonal temperate environments. It also corresponds to the beginnings of Upper Paleolithic art—realistic 3D representations of game animals on stone, clay, bone, and ivory. The common denominator seems to be an increased capacity to store spatiotemporal information, i.e., the ability to imagine objects, particularly game animals, and how they move over space and time. If IQ tests fail to measure this capacity, it may be worthwhile to test carriers of this allele for artistic or map-reading skills.

ASPM - Does the Middle Eastern/West Eurasian allele assist processing of alphabetical script?

ASPM is another gene that regulates brain growth, and like Microcephalin it continued to evolve after modern humans had spread out of Africa, its latest allele arising about 6000 years ago somewhere in the Middle East. The new allele then proliferated within and outside this region, reaching higher incidences in the Middle East (37-52%) and in Europe (38-50%) than in East Asia (0-25%). Despite its apparent selective advantage, this allele does not seem to improve cognitive performance on standard IQ tests. On the other hand, there is evidence that it is associated with increased brain size (Montgomery and Mundy, 2010).

At present, we can only say that it probably assists performance on a task that exhibited the same geographic expansion from a Middle Eastern origin roughly 6000 years ago. The closest match seems to be the invention of alphabetical writing, specifically the task of transcribing speech and copying texts into alphabetical script. Though more easily learned than ideographs, alphabetical characters place higher demands on mental processing, especially under premodern conditions (continuous text with little or no punctuation, real-time stenography, absence of automated assistance for publishing or copying, etc.). This task was largely delegated to scribes of various sorts who enjoyed privileged status and probably superior reproductive success. Such individuals may have served as vectors for spreading the new ASPM allele (Frost, 2008; Frost, 2011).

Tay Sachs and IQ

Ashkenazi Jews have high incidences of certain neurological conditions, particularly Tay Sachs, Gaucher's disease, and Niemann-Pick disease. In the homozygous state these conditions are deleterious, but in the heterozygous state they may improve intellectual capacity by increasing neural axis length and branching. Cochran et al. (2006) argue that this improvement could amount to about 5 IQ points.

There was in fact a study in the 1980s to determine whether Tay-Sachs heterozygotes suffer from mental deficits (Kohn et al., 1988). The authors found no deficits but did not elaborate on whether performance was above-normal on the neuropsychological tests. They did mention that about two thirds of the Tay-Sachs heterozygotes had education beyond high school.

The raw data seem to be long gone, but it would not be difficult to repeat the study with a view to studying above-normal mental performance in heterozygotes and non-carriers.

References

Boas, F. (1974). A Franz Boas Reader. The Shaping of American Anthropology, 1883-1911, G.W. Stocking Jr. (ed.), Chicago: The University of Chicago Press.

Cochran, G., J. Hardy, and H. Harpending. (2006). Natural history of Ashkenazi intelligence, Journal of Biosocial Science, 38, 659-693.

http://harpending.humanevo.utah.edu/trial.link/Ashkenazi.pdf

Evans, P. D., Gilbert, S. L., Mekel-Bobrov, N., Vallender, E. J., Anderson, J. R., Vaez-Azizi, L. M., et al. (2005). Microcephalin, a gene regulating brain size, continues to evolve adaptively in humans, Science, 309, 1717-1720.

http://www.fed.cuhk.edu.hk/~lchang/material/Evolutionary/Brain%20gene%20and%20race.pdf

Frost, P. (2008). The spread of alphabetical writing may have favored the latest variant of the ASPM gene, Medical Hypotheses, 70, 17-20.

http://www.sciencedirect.com/science/article/pii/S0306987707003234

Frost, P. (2011). Human nature or human natures? Futures, 43, 740-748. http://dx.doi.org/10.1016/j.futures.2011.05.017

Gene Expression. (2006). 10 Questions for Bruce Lahn.

http://www.gnxp.com/blog/2006/10/10-questions-for-bruce-lahn_10.php

Kohn, H., P. Manowitz, M. Miller, and A. Kling. (1988). Neuropsychological deficits in obligatory heterozygotes for metachromatic leukodystrophy, Human Genetics, 79, 8-12.

Mekel-Bobrov, N., Posthuma, D., Gilbert, S. L., Lind, P., Gosso, M. F., Luciano, M., et al. (2007). The ongoing adaptive evolution of ASPM and Microcephalin is not explained by increased intelligence, Human Molecular Genetics, 16, 600-608.

http://psych.colorado.edu/~carey/pdfFiles/ASPMMicrocephalin_Lahn.pdf

Montgomery, S. H., and N.I. Mundy. (2010). Brain evolution: Microcephaly genes weigh in, Current Biology, 20, R244-R246.

http://www.sciencedirect.com/science/article/pii/S0960982210000862

Piffer, D. (2013). Factor analysis of population allele frequencies as a simple, novel method of detecting signals of recent polygenic selection: The example of educational attainment and IQ, Mankind Quarterly, 54, 168-200.

http://emilkirkegaard.dk/en/wp-content/uploads/Factor-Analysis-of-Population-Allele-Frequencies-as-a-Simple-Novel-Method-of-Detecting-Signals-of-Recent-Polygenic-Selection-The-Example-of-Educational-Attainment-and-IQ.pdf

Rushton, J. P., Vernon, P. A., and Bons, T. A. (2007). No evidence that polymorphisms of brain regulator genes Microcephalin and ASPM are associated with general mental ability, head circumference or altruism, Biology Letters, 3, 157-160.

http://semantico-scolaris.com/media/data/Luxid/Biol_Lett_2007_Apr_22_3(2)_157-160/rsbl20060586.pdf

Ward, M.E., G. McMahon, B. St Pourcain, D.M. Evans, C.A. Rietveld, et al. (2014). Genetic variation associated with differential educational attainment in adults has anticipated associations with school performance in children. PLoS ONE 9(7): e100248. doi:10.1371/journal.pone.0100248

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0100248#pone-0100248-g002

In a recent post, Fred Reed asks:

Why should I not indulge my hobby of torturing to death the severely genetically retarded? This would seem beneficial. We certainly don't want them to reproduce, they use resources better invested in healthy children, and it makes no evolutionary difference whether they die quietly or screaming.

The short answer is that any killing, for whatever reason, increases the likelihood of killing for other reasons. One exception is self-defence, but that's not done for pleasure. Another exception is capital punishment, but that, too, is not done for pleasure. More to the point, no single citizen can carry out an execution. It requires a lengthy judicial process. The same reasoning applies to the final exception of war. No single citizen can declare war.

It's not for nothing that killing is so taboo, especially recreational killing. Several things have contributed to the success of Western societies, but a leading one is the relatively peaceful nature of social relations. When people can go about their business without fearing for their lives, much becomes possible that otherwise would not be. This taboo is so crucial that we even extend it to nonhumans. Cats and dogs have no inherent right to life, yet it is a serious offence to torture them to death.

That's society. What about biology?

At this point, Fred may speak up: "But those are social reasons against killing of any sort. What are the biological reasons?"

The immediate biological reason is empathy. If I try to hurt someone, I feel the pain I inflict. Truth be told, the only life forms I enjoy killing are flies and mosquitoes. If a moth flies into our home, I'll go to some length to capture it and set it free outside, and I know others who do similar things. Just think of all the car drivers who come to a screeching halt to avoid running over some poor animal.

It's empathy that makes me and others act that way. And I cannot easily turn it off. It shuts down only when feelings of contempt enter my mind, as with those contemptible flies and mosquitoes.

Empathy is hardwired. It's 68% heritable in the case of affective empathy, i.e., the capacity to respond with the appropriate emotion to another person's mental state (Chakrabarti and Baron-Cohen, 2013). To date, studies have focused on disorders caused by too much empathy or too little. Psychopaths may have intact cognitive empathy, but impaired affective empathy. They keenly understand how others feel without actually experiencing those feelings. The reverse impairment may affect autists. As for depressives, they may suffer from being too sensitive to the distress of others and to guilt over not helping them enough.

These disorders exist at the tail ends of a normal distribution. By focusing on these extremes, we forget the variability among healthy individuals. We all vary in our capacity for empathy, just as we do for almost any mental capacity.

How can evolution explain empathy?

Why do we feel empathy? How could natural selection favor such selflessness? This is of course the point that Fred is trying to make. Empathy keeps us from doing things that supposedly make evolutionary sense. Therefore, it could not have evolved. It must have been given to us by a Great Designer.

But why did this Great Designer give more of it to some people than to others? We're talking about a heritable trait. It's not as if everyone starts off the same way, with some later falling behind through their own wrongdoing.

And how has the Great Designer preserved this selfless behavior? Unless something is done, empathic people will eventually be overwhelmed by a tidal wave of cheaters, free riders, and people shouting "Gimme! Gimme! Gimme!" This is as much a mystery for creationists as it is for evolutionists. It's one thing to explain how altruism came to be. It's another to explain how it manages to survive in this cynical world.

These questions passed through my mind when I was going through my late mother's effects. I discovered she had for years been donating money for various projects in the Third World, at a time when she was a widow with no pension. Meanwhile, as a teenager, I had to take on all kinds of odd jobs to help us make ends meet. Looking over those donor receipts I shook my head and felt some resentment. How do good Christians like her manage to survive?

Yet she did, like others before her. For one thing, she was suspicious of strangers, and this suspicion extended to some ethnic groups more than to others. She was prejudiced and "postjudiced." If someone acted dishonestly with her once too often, she would have no more to do with him or her. Such people were "contemptible."

Today, that sort of behavior might seem un-Christian. But her Christianity was of an older, judgmental sort, being inspired more by the punitive Old Testament than by the forgiving New Testament. She would judge people, and her judgment could be harsh, very harsh.

Over space and time

Just as the capacity for empathy varies from one individual to another, it also varies statistically from one human population to another, being strongest in the "guilt cultures" of Northwest Europe. Guilt is the twin sister of empathy. Both flow from a simulation of how another person thinks or feels (an imaginary witness to a wrongdoing, a person in distress) and both ensure correct behavior by inducing the appropriate feelings (anguish, pity).

Why are guilt and empathy so strong in Northwest Europeans? Other societies ensure good behavior by relying on close kin to step in and enforce social rules. This policing mechanism has been less effective west of the Hajnal line (which runs roughly from Trieste to St. Petersburg) because kinship ties have been correspondingly weaker. There has thus been stronger selection for internal means of behavior control, like guilt and empathy.

This zone of relatively weak kinship is associated with unusual demographic tendencies, called the Western European Marriage Pattern:

- relatively late marriage for men and women

- many people who never marry

- neolocality (children leave the family household to form new households)

- high circulation of non-kin among different households (Hajnal, 1964; ICA, 2013)

The Western European Marriage Pattern was thought to have arisen after the Black Death of the 14th century. There is now good evidence for its existence before the Black Death and fragmentary evidence going back to 9th century France and earlier (Hallam, 1985; Seccombe, 1992, p. 94). Historian Alan Macfarlane likewise sees an English tendency toward weaker kinship ties before the 13th century and even during Anglo-Saxon times (Macfarlane, 2012; Macfarlane, 1992, pp. 173-174). I have argued that this tendency probably goes still farther back (Frost, 2013a; Frost, 2013b).

Whatever the ultimate cause, Northwest Europeans seem to have been pre-adapted for later shifts away from kinship and toward alternate means of organizing social relations (i.e., ideology, codified law, commerce). This tendency has taken various forms: the intense guilt-driven Christianity of the Anglo-Saxon penitential tradition and, later, Protestantism; the medieval alliance between Church and State to pacify social relations; and the post-medieval rise of the market economy. This cultural evolution has been described by the historical economist Gregory Clark for the English population between the 12th and 19th centuries. As England became a settled society, success went to those who could resolve disputes amiably and profit from thinking ahead—in short, those who had middle-class values of thrift, foresight, self-control, nonviolence, and sobriety. This English middle class, initially tiny, grew in numbers until its lineages accounted for most of its country’s gene pool (Clark, 2007; Clark, 2009a; Clark, 2009b).

But what does that have to do with evolution???

At this point, Fred may again speak up, with more than a touch of exasperation: "You're ducking my question! You're talking about culture, society, and religion! What does that have to do with evolution???"

Everything, Fred. Everything. Unlike other animals, humans have to adapt not only to their physical environment but also to their cultural environment. In short, we've become participants in our own evolution. We have domesticated ourselves.

Let me return to your initial question. What's to stop you from torturing to death the severely retarded? First, your sense of empathy should. If it doesn't, you're the one with a severe mental defect. I wouldn't want you as a fellow citizen, let alone as a neighbor. The law of the jungle may give you the right to torture defenceless people to death, but it also gives me the right to organize a lynch mob and hang you from the nearest tree.

References

Clark, G. (2007). A Farewell to Alms. A Brief Economic History of the World, Princeton: Princeton University Press.

Clark, G. (2009a). The indicted and the wealthy: Surnames, reproductive success, genetic selection and social class in pre-industrial England.

http://www.econ.ucdavis.edu/faculty/gclark/Farewell%20to%20Alms/Clark%20-Surnames.pdf

Clark, G. (2009b). The domestication of man: The social implications of Darwin. ArtefaCTos, 2, 64-80.

http://campus.usal.es/~revistas_trabajo/index.php/artefactos/article/viewFile/5427/5465

Frost, P. (2013a). The origins of Northwest European guilt culture, Evo and Proud, December 7

http://evoandproud.blogspot.ca/2013/12/the-origins-of-northwest-european-guilt.html

Frost, P. (2013b). Origins of Northwest European guilt culture, Part II, Evo and Proud, December 14

http://evoandproud.blogspot.ca/2013/12/origins-of-northwest-european-guilt.html

Hajnal, John (1965). European marriage pattern in historical perspective. In D.V. Glass and D.E.C. Eversley (eds). Population in History. Arnold, London.

Hallam, H.E. (1985). Age at first marriage and age at death in the Lincolnshire Fenland, 1252-1478, Population Studies, 39, 55-69.

ICA (2013). Research Themes - Marriage Patterns, Institutions for Collective Action

http://www.collective-action.info/_THE_MarriagePatterns_EMP

Macfarlane, A. (1992). On individualism, Proceedings of the British Academy, 82, 171-199.

http://www.alanmacfarlane.com/TEXTS/On_Individualism.pdf

Macfarlane, A. (2012). The invention of the modern world. Chapter 8: Family, friendship and population, The Fortnightly Review, Spring-Summer serial

http://fortnightlyreview.co.uk/2012/07/invention-8/

Seccombe, W. (1992). A Millennium of Family Change. Feudalism to Capitalism in Northwestern Europe, London: Verso.

A highwayman - by Glen Campbell (source). Before the rise of the State, and its pacification of social relations, the top man was the one who dominated the local group through a mixture of violence, bombast, and charisma.

Before the State came into being, men were organized into small, loosely defined groups where authority was wielded through a mixture of violence, bombast, and charisma. The more you had of these qualities, the likelier you would become the leader, "the big man." But such leadership could easily slip out of your hands. Power was something that all men held, and it was only through the consensus of the moment that one man held more of it than the others.

Thus, in pre-State societies, power is not a permanent structure that transcends the lifetime of any one leader. Power is the leader. It is highly personal and ephemeral, and these qualities extend to the tools of power, like speech. When describing Amerindian tribes in Paraguay, Pierre Clastres (1989 pp. 151-153) says:

To speak is above all to possess the power to speak. [...] the question to ask is not: who is your chief? but rather: who among you is the one who speaks? The master of words is what many groups call their chief.

[...] Indian societies do not recognize the chief's right to speak because he is the chief: they require that the man destined to be chief prove his command over words. Speech is an imperative obligation for the chief. The tribe demands to hear him: a silent chief is no longer chief.

This situation changes with the rise of the State, in particular with its monopoly on the use of violence. Social relations become more pacified, more structured, and less changeable, thus creating a culture of deference to authority. Speech is still manipulative but subtly so, as Rosen (1987) describes in Ethiopia:

For people who grow up speaking Amharic and Tigrinya, the idea of being precise with language is a foreign one. Ethiopians, perhaps Amharas more than Tigreans, are always on guard with others, suspicious about the motives of almost everyone, and on the alert for verbal assaults of one sort or another. The Amhara does not assume good intentions—he expects people to harbor disruptive inclinations. He deals with authority cautiously, always seeking to perfect his verbal means for giving vent to his criticisms and frustrations, but without incurring the wrath of powerful superiors.

[...] One must live a long time in the midst of Ethiopians, speaking with them in Amharic (or Tigrinya), in order to begin to appreciate how much calculation is invested in each phrase, each answer to a question, each overt response to a situation. That he who desires to do harm may always be polite, or that he who wishes to deliver an insult may include it in a finely-wrought compliment, is part of a general understanding of human nature. When a person speaks, he wants to do so subtly, being able to make his point effectively, yet not so directly that he might find himself involved in an altercation or worse with some equally sensitive opponent.

Social relations are still incompletely pacified in Ethiopia. This is partly because of recurring conflicts between central and peripheral sources of authority, but also because many people chose until recent times to be outlaws, i.e., those outside the sphere of State-imposed law:

In Ethiopia, an exceptionally fierce warrior could not always restrict himself to serving the common cause, or to being subservient to a particular chieftain. His alternative was to rebel, flee from the constraints of society and become a shifta. The dictionary defines this term to mean "outlaw, bandit, brigand, rebel". It was applied to anyone who committed a crime and then fled to the wilderness, thereafter living by stealth and cunning, if not, as was more than likely, by killing and highway robbery. As often as not, the shifta was also admired for being guabäz: for his courage and manliness, and, perhaps, most of all, for his daring in flouting the norms of the society. (Rosen, 1987)

Incomplete pacification also appears in the persistence of disruptive forms of speech, "when language is made into a weapon to attack or disrupt others":

One form of this is an Ethiopian penchant for backbiting, known in Amharic as chiqechiq. This appears when personal interests are asserted in the midst of group undertakings, often leading to the downfall of the community plan or project, and the disruption of joint undertakings. Another form is the studied use of hyperbole in order to magnify a case, or to gain attention for one's cause, even if this requires wild exaggeration of the truth. (Rosen, 1987)

Emergence of a free marketplace of ideas

I have argued elsewhere that the State's monopoly on violence created a new cultural environment that favored the survival of meeker and more submissive individuals (Frost, 2010). This environment also improved the prospects for individuals who used speech less aggressively. Because other individuals no longer posed a threat to life and property, and because trust had become the rule and not the exception, people were now freer to use speech simply for communication. It became possible to exchange ideas in good faith and judge them on their own merits.

This development is analogous to the rise of the market economy. In a low-trust society, buyers and sellers can securely make their transactions only in small protected areas that are limited in space and time, i.e., shops and marketplaces. In a high-trust society, the market mechanism can spread beyond these isolated points of exchange to encompass the entire economy. Increased trust emancipated the marketplace of goods and services, and it had a similar effect on the marketplace of ideas.

Cultural or genetic evolution?

Selection acts on phenotypes, and only indirectly on genotypes. When speech began to be used in new ways, the old ways became a handicap for survival and reproduction. There was thus cultural selection for new speech patterns. But were these new patterns passed on only through learning? Or was there also selection for certain genetic predispositions?

There are predispositions that selection can act upon. Loudness of speech seems to have a heritable basis (Carmelli et al., 1988; Matthews et al., 1984). The same is true for deceitful behavior (Barker et al., 2009). Heritability is particularly high for Attention-Deficit/Hyperactivity Disorder (ADHD), which is characterized by certain speech differences:

Analysis of speech parameters during conversation, such as voice rhythm (rate and duration of pauses and vocalization, response latency), intensity, and frequency, has revealed marked differences in the timing and modulation of speech between children with ADHD and those with and without specific learning disabilities. They speak louder, fail to modulate their voice volume, speak for much longer at a stretch with many short pause durations during their talk, but take much longer to respond to the conversational partner. (Tannock, 2005)

This is not to say that ADHD became less prevalent with the pacification of social relations, but rather that this new cultural environment selected for certain heritable aspects of speech that are impaired by ADHD. Like many other genetic disorders, ADHD sheds light on the heritable variability that selection can act upon.

In sum, when the State imposed a monopoly on the use of violence, it set in motion a process of gene-culture co-evolution with many consequences. Among other things, this process may have favored not only learned ways of speaking but also unlearned ways as well.

References

Barker, E.D., H. Larson, E. Viding, B. Maughan, F. Rijsdijk, N. Fontaine, and R. Plomin. (2009). Common genetic but specific environmental influences for aggressive and deceitful behaviors in preadolescent males, Journal of Psychopathology and Behavioral Assessment, 31, 299-308.

http://www.drru-research.org/data/resources/55/Barker-E.-et-al.-2009.PDF

Carmelli, D., R. Rosenman, M. Chesney, R. Fabsitz, M. Lee, and N. Borhani. (1988). Genetic heritability and shared environmental influences of type A measures in the NHLBI Twin Study, American Journal of Epidemiology,127 (5), 1041-1052.

Clastres, P. (1989). Society against the State, New York: Zone Books.

Frost, P. (2010). The Roman State and genetic pacification, Evolutionary Psychology, 8(3), 376-389. http://www.epjournal.net/filestore/EP08376389.pdf

Matthews, K.A., R.H. Rosenman, T.M. Dembroski, E.L. Harris, and J.M. MacDougall. (1984). Familial resemblance in components of the type A behavior pattern: a reanalysis of the California type A twin study, Psychosomatic Medicine, November, 46, 512-22.

Rosen, C. (1987). Core symbols of Ethiopian identity and their role in understanding the Beta Israel today, in M. Ashkenazi and A. Weingrod (eds.) Ethiopian Jews and Israel, pp. 55-62, New Brunswick (U.S.A.): Transaction Books.

Tannock, R. (2005). Language and mental health disorders: the case of HDHD, in W. Ostreng (ed.) Convergence. Interdisciplinary Communications 2004/2005, 45-53.

http://www.cas.uio.no/Publications/Seminar/Convergence_Tannock.pdf

Originally from south China, Austronesians spread successively outward to Taiwan, Southeast Asia, and Oceania. Was farming the secret of their success? Or was it their mental makeup? (source: French Wikipedia - Maulucioni)

About 10,000 years ago, the pace of human genetic evolution rose a hundred-fold (Hawks et al., 2007). Our ancestors were no longer adapting to slowly changing physical environments. They were adapting to rapidly evolving cultural environments.

What, exactly, caused this speed-up? The usual answer is the shift from hunting and gathering to farming, which in turn caused other changes. People were becoming sedentary and living in ever larger communities: villages, towns, and finally cities. Farming also produced a food surplus to be stored for future use, thereby providing powerful men with the means to bankroll a growing number of servants, soldiers, and other hangers-on. Thus began the formation of early states. And thus ended the primitive equality of hunter-gatherers.

But is that the whole story? Was farming the trigger for this chain of events? Or did something earlier get things going? More and more anthropologists are taking a closer look at what happened just before the advent of farming, a period called the "Broad Spectrum Revolution":

All Paleolithic hominids lived by hunting and collecting wild foods, an aspect of existence that began to disappear only with the emergence of the farming and herding societies of the Neolithic ≤10,000 years ago (10 KYA). What are the roots of this remarkable economic transformation? The answer lies in equally revolutionary changes that took place within certain stone age cultures several millennia before. In 1968, Lewis R. Binford noted what appeared to be substantial diversification of human diets in middle- and high-latitude Europe at the end of the Paleolithic, roughly 12-8 KYA. Rapid diversification in hunting, food processing, and food storage equipment generally accompanied dietary shifts, symptoms of intensified use of habitats, and fuller exploitation of the potential foodstuffs they contained. (Stiner, 2001).

Farming thus came on the heels of a broader cultural, behavioral, and even psychological revolution. It is this broader change, rather than farming alone, that probably caused many supposedly farming-related events, such as the rapid spread of certain agricultural peoples into territories that formerly belonged to hunter-gatherers. Examples include the Bantu expansion, which began about 4,000 years ago along the Nigerian/Cameroun border and spread east and south, eventually throughout almost all of central, eastern and southern Africa. There was also the more controversial Neolithic expansion, which started about 10,000 years ago in present-day Turkey and pushed north and west into Europe. Finally, there was the Austronesian expansion, which began over 6,000 years ago when Malay-speaking farmers crossed from south China to Taiwan. Then, some 4,000 years ago, they began to push rapidly into Southeast Asia and Oceania, finally reaching places as far apart as Easter Island and Madagascar.

Farming is said to have fueled all three demographic expansions. It created more food, which in turn created more people, who then bulldozed the less numerous hunter-gatherers out of existence. Yet this theoretical model does not fit the Austronesian expansion very well, as anthropologist Roger Blench points out:

The [existing] model proposes that it was the Austronesian adoption of an agricultural package, including rice, pigs and chickens, which allowed them to colonise Island SE Asia at the expense of resident hunter-gatherers. However, archaeology has signally failed to confirm this model. Early sites show very similar dates across a wide geographical area, suggesting that the first phase of post-Taiwan Austronesian expansion took place extremely rapidly. Pigs, dogs and chickens have been shown to arrive in ISEA via other routes and rice is conspicuously absent in most places. This paper argues that this model has effectively inverted the actual situation, and that the Austronesian expansion was the consequence of a failed agricultural revolution and a reversion to opportunistic foraging. (Blench, 2014)

There was no "package" of domesticated plants and animals that enabled Austronesians to overwhelm the earlier inhabitants of Southeast Asia:

No remains of cereals of the relevant antiquity have been found in the Northern Philippines. Even today, the characteristic millets of the Asian mainland are barely represented in ISEA agriculture. Of the dogs, pigs and chickens originally thought to be part of the Austronesian 'package' only pigs cross the Taiwan Strait, and these now seem to be a local domestication not ancestral to the domestic pigs which are generally part of the Austronesian world. The apparent reconstructions for names of these domestic species formed part of the argument for their salience, but as Blench (2012) points out, these were based on chains of loanwords giving an appearance of spurious antiquity. (Blench, 2014)

Not only did the Austronesians bring a limited farming package to Southeast Asia, the existing peoples there already practiced a mix of farming and foraging:

Ellen (1988) describes this type of mixed vegeculture and arboriculture, a sedentary lifestyle based around sago extraction, for Seram in Eastern Indonesia. Stark (1996) touches on this hypothesis in a discussion of the archaeology of Eastern Indonesia, and Kyle Latinis (2000) discusses the broader role of arboriculture in early subsistence in ISEA. Hunt & Rushworth (2005) report evidence for disturbance in the tropical lowland forest at Niah, Sarawak, Malaysian Borneo at 6000 BP which they attribute to cultivation. Huw Barton (2012) has evidence from starch on stone pounders in the Kelabit highlands for palm granules earlier than 6500 BP. (Blench, 2014)

The incoming Austronesians really brought little, agriculturally speaking. In some cases, they actually reverted to foraging. In other cases, they adopted various crops and farm animals from the locals.

The picture is diverse, suggesting continued foraging, vegeculture, and sago starch extraction. Hence the concept that the maritime Austronesians reverted to a type of subsistence based on fishing, trading, possibly raiding and exchange of prestige goods. With their advanced sailing technology, they were well-placed to carry high-value goods from one exchange site to another. Their encounter with the Melanesian populations in Eastern Indonesia is certainly responsible for their adoption of vegeculture and domestic animals, but they were willing to drop and re-adopt these according to the circumstances of individual cultures they encountered. (Blench, 2014)

The Austronesians are often treated in the existing literature as a type-society for demographic expansion, with agriculture the underlying engine of growth. This is in increasing disaccord with the archaeology of the region, and this paper will suggest that the explanation is almost its inverse, that they succeeded precisely because they strategically reverted to foraging. (Blench, 2014)

What advantage, then, did the Austronesians have over the natives they displaced? There must have been something to offset the "home team" advantage of the natives, who knew the local environment better than anyone else.

The Austronesian advantage seems to have been threefold: (1) a more flexible and innovative approach; (2) a less present-oriented time orientation that extended further into the past and the future; and (3) a less individualistic approach to life that made collective goods and goals more possible.

Flexibility and innovation

Blench (2014) states: “Austronesians quickly reinvented themselves, incorporating regional innovations into their cultural repertoire. Apart from their own distinctive pottery, they must have quickly seized on other early trade possibilities, obsidian, stone axes, woven goods and baskets. By the time they begin to reach uninhabited islands they have constructed Austronesian culture out of fragmentary elements adopted from a wide range of sources.”

Time orientation

The Austronesians saw themselves as the embodiment of lineages that stretched backwards into the past and forwards into the future. Preservation of genealogies seems to have been a typical cultural trait of Austronesian peoples, and this ancestor worship fostered a widespread desire among them to become revered ancestors. Quoting an earlier author, Blench (2014) points to "a culturally sanctioned desire to found new settlements in order to become a revered or even deified founder ancestor in the genealogies of future generations." The rapidity of the Austronesian expansion was thus, in part, ideologically driven.

Collectivism

Blench (2014) refers to "the striking differences between Austronesians in contact with Melanesians, whose typical social structures were individualist, acephalous and marked by great diversity in approaches to religion and belief." Austronesian society was more hierarchical with caste-like elements, particularly priestly castes who acted as repositories of esoteric knowledge. Belief-systems were more homogeneous. Austronesian peoples have long shown evidence of strong religiosity, even those who have not converted to Hinduism, Islam, or Catholicism.

Conclusion

One of my professors, Bernard Arcand, would talk to us about the hunter-gatherers of Upper Amazonia and their indifference to farming. They saw it as something akin to slavery and couldn't understand why anyone would want to stay put in one place and toil in the fields all day. Attempts to teach them the benefits of farming typically failed. Benefits? What benefits?

There has to be a change in mental makeup before farming becomes possible. People must become willing to exchange short-term pain for long-term gain. They must accept monotony and sedentary living. They must live in larger communities with people who are not necessarily close kin. And they must get used to bland, nutrient-poor food.

Anthropology has long tried to explain human societies in terms of their modes of subsistence: hunting and gathering, farming, industrial capitalism. This material basis of society is thus the source of our mental makeup. In reality, the two have coevolved with each other. Moreover, when humans adapt to a certain mode of subsistence, they may become "pre-adapted" to later ones. We associate the dawn of civilization with a shift toward future time orientation and a resulting complexification of technology, yet this shift seems to have first begun among hunter-gatherers of the sub-Arctic, where the yearly cycle required development of technologies for storage, meat refrigeration, and heat conservation, as well as other means to collect unpredictable and widely dispersed resources. This 'first industrial revolution' pre-adapted early modern humans for later cultural developments in places farther south.

It is perhaps no coincidence that most of the human gene pool ultimately came from people who, more than 10,000 years ago, roamed the northern wastes of Eurasia. Such people were ancestral to many southward-pushing demographic expansions, including the one that would give rise to the Austronesians (Frost, 2014).

References

Blench, R. (2014). The Austronesians: An agricultural revolution that failed, To be presented at the Second International Conference on Taiwan Indigenous Peoples, 15-17 September 2014 Shung Ye Museum, Taipei, Taiwan

http://rb.rowbory.co.uk/Archaeology/Oceania/Blench%20Austronesian%20Taipei%202014%20agric%20failed.pdf

Cochran, G. and H. Harpending. (2009). The 10,000 Year Explosion: How Civilizations Accelerated Human Evolution, Basic Books, New York.

Frost, P. (2014). The first industrial revolution, Evo and Proud, January 18

http://evoandproud.blogspot.ca/2014/01/the-first-industrial-revolution.html

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2410101/

Stiner, M.C. (2001). Thirty years on the "Broad Spectrum Revolution" and paleolithic demography, Proceedings of the National Academy of Sciences, 98(13), 6993-6996.

http://hatayup.web.arizona.edu/pubs/stiner2001.pdf

Still from the film Is Matrimony a Failure?(1922). Who's making more babies? "Good boys" or "bad boys"? Originally, the good boys were, thanks to parental monitoring of relations between single men and single women. The pendulum then swung toward the bad boys in the 1940s, only to swing back after the 1960s.

A recent Swedish study has found that "bad boys" are outbreeding "good boys":

Convicted criminal offenders had more children than individuals never convicted of a criminal offense. Criminal offenders also had more reproductive partners, were less often married, more likely to get remarried if ever married, and had more often contracted a sexually transmitted disease than non-offenders. Importantly, the increased reproductive success of criminals was explained by a fertility increase from having children with several different partners. (Yao et al., 2014)

This study has been much talked about, yet few people have noticed its one big flaw. Sweden has many citizens of foreign origin whose crime and fertility rates exceed those of the native population (Crime in Sweden, 2014; Landes, 2008). Reproductive success may thus correlate with criminality simply because both tend to be higher among non-natives than among natives. Admittedly, this alternate explanation had been foreseen by the authors of the study and they tried to correct for it:

We included variables potentially associated with both criminal and reproductive behavior as covariates. [...] Immigrant status has been associated with both rule breaking, primarily through associations with other familial and socioeconomic risk markers (Moehling & Piehl, 2009), and adherence to cultural norms influencing fertility and monogamy-related outcomes (Coleman, 2006). The migration register provided information on immigrant status defined as being born in Sweden or not. (Yao et al., 2014)

Unfortunately, country of birth is no longer a satisfactory proxy for cultural identity, at least not in Sweden's case. There is now a large Swedish-born population that self-identifies as Pakistani, Somali, or Afghan, including the youths who rioted in Malmö last year. The Swedish crime rate is influenced almost as much by the Swedish-born of foreign background as by the foreign-born:

During the period 1997-2001, 25% of the almost 1,520,000 offences for which a perpetrator was convicted were committed by people born in the Middle East or Eastern Europe, while almost 20% were committed by people with a foreign background who were born in Sweden. (Crime in Sweden, 2014)

If we could examine only people of Swedish descent, I doubt reproductive success would still correlate with criminality or, more exactly, with a tendency to "love and leave" one woman after another. Such a correlation used to exist in the U.S. but disappeared almost half a century ago. This was the conclusion of Jason Malloy and JayMan (2012) when they used General Social Survey data to find out the number of children fathered by monogamous men ("good boys") versus men who had several female sex partners ("bad boys"). It seems that the reproductive success of bad boys has varied a lot over time:

Men born before 1920 - courtship under parental supervision

In this cohort, good boys were the top breeders. No need to think hard to find the reason. Any man wishing to meet a single woman, other than a prostitute, had to run a gauntlet of parental supervision. The preferred form of courtship was still "calling." If a woman struck your fancy, you could "call" on her at her home. If she and her parents were favorably impressed, you could come back for further visits and eventually start taking her out to social events. Otherwise, that would be the end of it. A more direct approach could get you in big trouble, as a reference book for American lawmakers explained in 1886:

The state should punish, not only treacherous inducements to incontinence or to unchastity when accompanied by the violation of particular duties, and the seduction of minors, or girls under sixteen, but also seduction when it assumes a character dangerous to the interests of the community. It is not the duty of the state to make the individual moral, or to protect her against temptations to immorality; but it should endeavor to prevent all acts of immorality calculated to poison family life and the life of the nation. (Lalor, 1886, vol.III, p. 211)

The concern here is not just venereal disease, but also a family's genetic heritage. In the 19th century, people believed that a part of their essence was reincarnated in their children and grandchildren. Their concern over sex was fueled not by irrational hang-ups but by a very rational desire to maintain the integrity of their family line. Bad boys threatened that integrity, and it was not for nothing that many ended up in jail ... or at the end of a rope.

Men born between 1920 and 1939 - rise of dating, illegitimacy, and adoption

In this cohort, bad boys were the top breeders. Parental supervision had slackened with the replacement of calling by dating, thus creating new opportunities for them to sow their seed. A sharp rise in illegitimacy led to a sharp rise in adoption:

[...] The period 1945 to 1974, the baby scoop era, saw rapid growth and acceptance of adoption as a means to build a family. Illegitimate births rose three-fold after World War II, as sexual mores changed. Simultaneously, the scientific community began to stress the dominance of nurture over genetics, chipping away at eugenic stigmas. In this environment, adoption became the obvious solution for both unwed mothers and infertile couples. (Adoption, 2014)

Adoption had previously been very rare. As late as 1923, only 2% of children without parental care ended up in adoptive homes, the others going to foster homes or orphanages (Adoption, 2014). And a large chunk of that 2% involved adoptions between related families. These statistics are mirrored by my family tree: whenever children were left with no provider, they would be adopted by an aunt or an uncle or placed in a foster home. In those days, changing your family identity was as unthinkable as changing your religion or nationality.

To deal with the surge of illegitimacy, progressive-minded people now turned toward a seemingly great idea. On the one hand, there were babies abandoned by deadbeat dads. On the other, there were middle-class families with loving homes. Why not transfer these babies from the dads who don't love them to the ones who can?

The 20th century is littered with great ideas that proved to be not so great. Adoption is no exception. One negative outcome, which could have been foreseen, is that adopted children tend to replicate the psychological profile of their biological fathers. In one study, Gibson (2009) notes:

Adoptees were more likely than genetic offspring to have ever received public assistance, been divorced or been arrested. They also completed fewer years of schooling and were more likely to have ever required professional treatment for mental health, alcohol and drug issues.

[...] This supports other research showing that, compared to genetic children, American adoptees have a higher overall risk of contact with mental health professionals, specifically for eating disorders, learning disabilities, personality disorders and attention deficit hyperactivity disorder [...] They also have lower achievement and more problems in school, abuse drugs and alcohol more, and fight with or lie to parents more than genetic children [...]

These problems are not due to adoptive parents shortchanging adoptees. In fact, the reverse seems true:

This study categorically fails to support the hypothesis that parents bias investment toward genetically related children. Every case of significant differential investment was biased toward adoptees. Parents were more likely to provide preschool, private tutoring, summer school, cars, rent, personal loans and time with sports to adopted children. (Gibson, 2009)

Adoption does seem to improve the behavior of these children. It lowers their risk of committing violent crime, although they remain just as likely to commit other offences:

The possibility that genetic factors are among the causes of criminal behavior was tested by comparing court convictions of 14,427 adoptees with those of their biological and adoptive parents. A statistically significant correlation was found between the adoptees and their biological parents for convictions of property crimes. This was not true with respect to violent crimes. There was no statistically significant correlation between adoptee and adoptive parent court convictions. Siblings adopted separately into different homes tended to be concordant for convictions, especially if the shared biological father also had a record of criminal behavior. (Mednick et al., 1984)

With respect to intellectual capacity, adoptees likewise seem to benefit from their new homes, although the benefit tends to wash out over time. When children with two white biological parents were adopted into white middle-class homes, they initially did somewhat better than their non-adopted siblings, as seen on IQ tests at the age of 7. By the age of 17, however, the situation had reversed, with the adoptees falling behind their non-adopted siblings in terms of IQ, GPA, class ranking, and school aptitude (Minnesota Transracial Adoption Study, 2014).

Clearly, adoptees are getting some benefit although the benefit is less than what some may think. It also comes at a price. When the family unit is reoriented toward social welfare goals, it can no longer serve its original purpose of perpetuating a genetic heritage.

Men born after 1939 - separation of sex from reproduction

In this cohort, good boys have once again been the top breeders. This might seem counterintuitive. After all, sexual morality has become even more liberal since the 1960s, and this change has paralleled a growing infatuation with thuggish males in popular culture. Yet something seems to have kept bad boys from translating their sexual success into reproductive success.

That "something" is easier access to contraception and ... Roe v. Wade. More and more good girls are making out with bad boys, but fewer and fewer are making babies with them.

Pro-lifers see this as proof that pro-choicers are secret eugenicists. I think it's just an unintended consequence. Paradoxically as it may seem, modern culture is favoring the reproduction of stable couples who plan for the long term and invest in their children.

Just think. What is the core message of modern culture? It's live for today, live for yourself, and avoid long-term commitments, such as family and children. And who responds the most to that message? It's people whose time orientation is already focused on the present and who already invest as little as possible in their offspring. Modern culture is sterilizing those individuals who are most susceptible to its message.

And so, when it comes to having babies and raising them to adulthood, America's white middle class is slowly but surely closing in on first place (Frost, 2012).

Conclusion

Perhaps this is all for the best. What other choices are there? Conservative politicians talk a lot about traditional values, but not one in ten believe what they say. To judge by their personal lives, many seem happy with the current climate of sexual permissiveness. Anyhow, if conservatives really do try to turn back the clock, their efforts will be blocked by the libertarian right and the liberal left. And if they manage to outflank both groups, they'll be lucky to take us back to the policies and practices of the 1950s. Unfortunately, this is one case where half-measures will make things worse. We've come to where we are because of the 1950s.

So what political option is left for someone like me? I wish to preserve our existing genetic heritage, if only because we don't fully understand what we are about to lose. If you feel the same way, the best course of action seems to be the present one of separating sex from reproduction. Call it "tactical liberalism" if you wish, but I see no other realistic alternative.

References

"Adoption" (2014) Wikipedia

http://en.wikipedia.org/wiki/Adoption

"Crime in Sweden" (2014). Wikipedia

http://en.wikipedia.org/wiki/Crime_in_Sweden

Frost, P. (2012). Obama: White America's bogeyman? Evo and Proud, November 24

http://evoandproud.blogspot.ca/2012/11/obama-white-americas-bogeyman.html

Gibson, K. (2009). Differential parental investment in families with both adopted and genetic children, Evolution and Human Behavior, 30, 184-189.

http://anthro.vancouver.wsu.edu/media/Course_files/anth-260-edward-h-hagen/evil_step-parents.pdf

JayMan. (2012). Some guys get all the babes - not exactly, JayMan's Blog, November 8

http://jaymans.wordpress.com/2012/11/08/some-guys-get-all-the-babes-not-exactly/

Lalor, J.J. (1886). Cyclopaedia of Political Science, Political Economy, and of the Political History of the United States, Chicago: A.H. Andrews & Co.

http://books.google.ca/books?hl=fr&lr=&id=AsM6AAAAIAAJ&oi=fnd&pg=PA1&dq=Cyclopaedia+of+Political+Science,+Political+Economy,+and+of+the+Political+History+of+the+United+States&ots=VqItRo_7kY&sig=aL3srydNpIpMoKOlKnd5gXqnp0g#v=onepage&q=Cyclopaedia%20of%20Political%20Science%2C%20Political%20Economy%2C%20and%20of%20the%20Political%20History%20of%20the%20United%20States&f=false

Landes, D. (2008). Higher birth rates among Sweden's foreign born, The Local, November 3

http://www.thelocal.se/20081103/15408

Mednick, S.A., W.F. Gabrielli Jr., & B. Hutchings. (1984). Genetic influences in criminal convictions: evidence from an adoption cohort, Science, 224, 891-894

http://www.sciencemag.org/content/224/4651/891.short

"Minnesota Transracial Adoption Study" (2014), Wikipedia

http://www.sciencemag.org/content/224/4651/891.short

Yao, S., N. Langstrom, H. Temri, and H. Walum. (2014). Criminal offending as part of an alternative reproductive strategy: investigating evolutionary hypotheses using Swedish total population data, Evolution and Human Behavior, in press

http://www.ehbonline.org/article/S1090-5138%2814%2900077-4/abstract

Great at reading or recognizing faces? You might not do so well on an IQ test. Source: Histoire naturelle générale et particulière avec la Description du Cabinet du Roy (1749) (Wikicommons)

The English psychologist Charles Spearman was the first to argue that a single factor, called "g," explains most of the variability in human intelligence. When observing the performance of children at school, he noticed that a child who did well in math would also do well in geography or Latin. There seemed to be a general factor that facilitates almost any kind of mental task.

Spearman did, however, acknowledge the existence of other factors that seem more task-specific:

[...] all branches of intellectual activity have in common one fundamental function (or group of functions), whereas the remaining or specific elements of the activity seem in every case to be wholly different from that in all the others.(Spearman, 1904, p. 284)

That is where things stood for over a century. In recent years, however, we’ve begun to identify the actual genes that contribute to intelligence. These genes are very numerous, numbering perhaps in the thousands, with each one exerting only a small effect. Many act broadly on intelligence in general and may correspond to the g factor, which seems to be a widespread property of neural tissue, perhaps cortical thickness or the integrity of white matter in the brain. Other genes act more narrowly on specific mental tasks. The ability to recognize faces, for instance, seems to have no relation at all to general intelligence. You can be great at recognizing faces while being as dumb as rocks (Zhu et al., 2009).

One way to locate these genes is through genome-wide association studies. We look at the various alleles of genes whose locations are already known, typically SNPs (single nucleotide polymorphisms), and see whether this source of variability correlates with variability in a mental trait. If we find a significant correlation, the genes for that trait must be nearby. The same kind of study can also show us how narrowly or broadly these genes act. Do they merely influence intelligence in general? Or do they provide more specific instructions? Such as how to recognize certain objects or how to react to them?

A genome-wide association study has recently shed light on various mental traits. In most cases, a common factor seems to explain about half of the genetic variability. This common factor is weakest for emotion identification, i.e., the ability to identify the emotions of other people by their facial expressions. Emotion identification actually correlates negatively with nonverbal reasoning (-0.25) and only weakly with verbal memory (0.17) and spatial reasoning (0.26). The highest correlation is with reading (0.40) and language reasoning. (0.45). Reading and language reasoning are highly intercorrelated, perhaps because they share the same mental module (Robinson et al., 2014).

This partial modularity has been confirmed by a recent twin study on reading and math ability. If we look at the genetic component of either reading or math ability, at least 10% and probably half affects performance on both tasks. Conversely, the other half is specific to either one or the other (Davis et al., 2014).

An evolutionary mystery?

But how can reading ability have a specific genetic basis if people began to read only in historic times? Indeed, history is said to begin with the first written documents. Surely humans weren't still evolving at that point?

To ask the question is to answer it. Not only were they still evolving, they were actually doing so at a faster pace than their prehistoric ancestors. Humans have undergone much more genetic change over the past 10,000 years than over the previous 100,000 (Hawks et al., 2007). This is a difficult fact to swallow, let alone digest, but we must learn to accept it and all of its implications.

The new findings on reading ability are consistent with other ones. The human brain has a special region, called the Visual Word Form Area, that is used to recognize written words and letters. If it is damaged, your reading ability will suffer but not your recognition of objects, names, faces, or general language abilities. There will be some improvement over the next six months, but reading will still take twice as long as it had previously. This brain region varies in size and organization from one individual to another and from one human population to another, being differently organized in Chinese people than in Europeans (Frost, 2014; Gaillard et al, 2006; Glezer and Riesenhuber, 2013; Levy et al., 2013; Liu et al., 2008).

Genome-wide association studies may help us pinpoint the actual genes responsible for the Visual Word Form Area. In fact, we may have already found one: ASPM. This gene influences brain growth in other primates and has evolved in humans right up into historic times. Its latest allele arose about 6000 years ago in the Middle East and proliferated until it reached incidences of 37-52% in Middle Easterners, 38-50% in Europeans, and 0-25% in East Asians. Despite its apparent selective advantage, this allele does not improve performance on IQ tests (Mekel-Bobrov et al.,2007; Rushton et al., 2007). It is nonetheless associated with larger brain size in humans (Montgomery and Mundy, 2010).

Its Middle Eastern origin some 6000 years ago suggests this allele may have owed its success to the invention of writing. Most people had trouble reading, writing, and copying lengthy texts in ancient times, when characters were written continuously with little or no punctuation. There was an acute need for scribes who could excel at this task, and such people were rewarded with reproductive success (Frost, 2008; Frost, 2011).

Conclusion

Human intelligence is modular to varying degrees, and much of this modularity seems to have arisen during historic times. It is a product of humans adapting not only to their physical environments but also to their more rapidly evolving cultural environments.

While there is such a thing as general intelligence, it seems to be only half of the picture. Two people may have the same IQ and yet differ significantly in various mental abilities. There may also be trade-offs between general intelligence and more specific mental tasks. If you're great at abstract reasoning, you may be lousy at decoding facial expressions. This may be because the two abilities compete with each other for limited mental resources. Or it may be that selection for abstract reasoning has occurred in an environment where people can trust each other and have no need to scrutinize facial expressions for signs of lying ... or imminent physical assault.

The same applies to human populations. Two populations may have the same mean IQ, and yet differ statistically over a large number of mental and behavioral traits. Although these differences may be scarcely noticeable if we compare two individuals taken at random from each population, their accumulative effect over many thousands of individuals can steer one population along one path of cultural evolution and the other along another. Furthermore, two populations may arrive at a similar outcome via different paths of cultural evolution and via different mental and behavioral packages. Europeans and East Asians have both reached an advanced level of societal development, but this similar outcome has been achieved in East Asian societies largely through external mediation of rule enforcement (e.g., shaming, peer pressure, family discipline) and in European ones mainly through internal means of control (e.g., guilt, empathy).

References

Davis, O.S.P., G. Band, M. Pirinen, C.M.A. Haworth, E.L. Meaburn, Y. Kovas, N. Harlaar, et al. (2014). The correlation between reading and mathematics ability at age twelve has a substantial genetic component, Nature Communications, 5

http://www.nature.com/ncomms/2014/140708/ncomms5204/full/ncomms5204.html

Frost, P. (2008). The spread of alphabetical writing may have favored the latest variant of the ASPM gene, Medical Hypotheses, 70, 17-20.

http://www.sciencedirect.com/science/article/pii/S0306987707003234

Frost, P. (2011). Human nature or human natures? Futures, 43, 740-748. http://dx.doi.org/10.1016/j.futures.2011.05.017

Frost, P. (2014). The paradox of the Visual Word Form Area, March 1, Evo and Proud

http://evoandproud.blogspot.ca/2014/03/the-paradox-of-visual-word-form-area.html

Gaillard, R., Naccache, L., P. Pinel, S. Clémenceau, E. Volle, D. Hasboun, S. Dupont, M. Baulac, S. Dehaene, C. Adam, and L. Cohen. (2006). Direct intracranial, fMRI, and lesion evidence for the causal role of left inferotemporal cortex in reading, Neuron, 50, 191-204.

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.76.7620&rep=rep1&type=pdf

Glezer, L.S. and M. Riesenhuber. (2013). Individual variability in location impacts orthographic selectivity in the "Visual Word Form Area", The Journal of Neuroscience, 33(27), 11221-11226.

http://www.jneurosci.org/content/33/27/11221.full

Hawks, J., E.T. Wang, G.M. Cochran, H.C. Harpending, and R.K. Moyzis. (2007). Recent acceleration of human adaptive evolution. Proceedings of the National Academy of Sciences (USA), 104, 20753-20758.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2410101/

Levy, J., J.R Vidal, R. Oostenveld, I. FitzPatrick, J-F. Démonet, and P. Fries. (2013). Alpha-band suppression in the Visual Word Form Area as a functional bottleneck to consciousness, NeuroImage, 78C, 33-45.

http://hal.inria.fr/docs/00/81/96/67/PDF/Levy_et_al.pdf

Liu, C., W-T. Zhang, Y-Y Tang, X-Q. Mai, H-C. Chen, T. Tardif, and Y-J. Luo. (2008). The visual word form area: evidence from an fMRI study of implicit processing of Chinese characters, NeuroImage, 40, 1350-1361.

http://www.yi-yuan.net/english/PAPERS/PAPERS_2008/2008_The-Visual-Word-Form-Area-Evidence.pdf

http://psych.colorado.edu/~carey/pdfFiles/ASPMMicrocephalin_Lahn.pdf

Montgomery, S. H., and N.I. Mundy. (2010). Brain evolution: Microcephaly genes weigh in, Current Biology, 20, R244-R246.

http://www.sciencedirect.com/science/article/pii/S0960982210000862

Robinson, E.B., A. Kirby, K. Ruparel, J. Yang, L. McGrath, V. Anttila, B.M. Neale, K. Merikangas, T. Lehner, P.M.A. Sleiman, M.J. Daly, R. Gur, R. Gur and H. Hakonarson. (2014). The genetic architecture of pediatric cognitive abilities in the Philadelphia Neurodevelopmental Cohort, Molecular Psychiatry, published online July 15

http://www.nature.com/mp/journal/vaop/ncurrent/full/mp201465a.html

http://semantico-scolaris.com/media/data/Luxid/Biol_Lett_2007_Apr_22_3(2)_157-160/rsbl20060586.pdf

Spearman, C. (1904). "General intelligence," objectively determined and measured, The American Journal of Psychology, 15, 201-292.

http://www.jstor.org/stable/1412107

Zhu, Q., Song, Y., Hu, S., Li, X., Tian, M., Zhen, Z., Dong, Q., Kanwisher, N. and Liu, J. (2009). Heritability of the specific cognitive ability of face perception, Current Biology, 20, 137-142.

http://web.mit.edu/bcs/nklab/media/pdfs/Zhu_et_al_Heritability.pdf

A widow about to be buried alive in her husband's grave (Wikimedia Commons). Do we all share the same sense of right and wrong?

What, ultimately, is the basis for morality? In a comment on a previous post, fellow columnist Fred Reed argued that some things are self-evidently wrong, like torture and murder. No need to invoke the Ten Commandments or any religious tradition. Some things are just wrong. Period.

This is a respectable idea with a long lineage. It's the argument of Natural Law. All people are born with a natural sense of right and wrong, and it is only later, through vice or degeneration, that some can no longer correctly tell the two apart.

The idea began with the Stoics of Ancient Greece. They believed that the universe is governed by laws and that everyone naturally wishes to live in harmony with them, thanks to the divine spark that exists in all of us. In reply, the Epicureans argued that the laws of the universe are indifferent to humans and their problems. We alone define right and wrong.

The Christian theologian Thomas Aquinas (1225-1274) worked out a compromise that divided Natural Law into general precepts and secondary precepts. The former are known to all men but can be hindered "on account of concupiscence or some other passion." The latter "can be blotted out from the human heart, either by evil persuasions [..] or by vicious customs and corrupt habits, as among some men, theft, and even unnatural vices, as the Apostle states (Rom. i), were not esteemed sinful" (Aquinas, Summa Theologica I-II, Q. 94, Art. 6).

Aquinas lived at a time when Christian morality had already penetrated deeply into the hearts and minds of Europeans. It was continually being violated, of course, but violators typically knew they had done wrong and they typically tried to justify their wrongdoings on Christian grounds, or seek absolution. Aquinian Natural Law thus closely approximated moral reality, much as Newtonian physics would long remain a good approximation of physical reality.

Things changed from the 16th century on, as Christian Europe spread outward into Africa, Asia, and the Americas. It became evident that notions of right and wrong were not everywhere the same, or even similar. One example was sati, the Indian custom of burning a widow alive on her husband's funeral pyre. Though supposedly voluntary, it usually involved the tying of her feet or legs to prevent escape. She could also be buried alive, as a 17th century traveler noted:

In most places upon the Coast of Coromandel, the Women are not burnt with their deceas'd Husbands, but they are buried alive with them in holes which the Bramins make a foot deeper than the tallness of the man and woman. Usually they chuse a Sandy place; so that when the man and woman both let down together, all the Company with Baskets of Sand fill up the hole about half a foot higher than the surface of the ground, after which they jump and dance upon it, till they believe the woman to be stiff'd. (Tavernier, 1678, p. 171; see also Sati, 2014)

When the British sought to ban the practice, they appealed to notions of right and wrong, but to no avail. Defenders of saticonsidered it right and even honorable. The debate was finally resolved by the logic of force, as set forth by the British commander-in-chief:

This burning of widows is your custom; prepare the funeral pile. But my nation has also a custom. When men burn women alive we hang them, and confiscate all their property. My carpenters shall therefore erect gibbets on which to hang all concerned when the widow is consumed. Let us all act according to national customs! (Napier, 1851, p. 35)

Enlightenment thinkers attributed this custom and others like it to degeneration from an original state of goodness. Thus was born the idea of the Noble Savage. Yet this idea, too, came under attack with the realization that even simple "uncorrupted" societies may have very different attitudes toward human life, as seen in the torturing of captives, the abandonment of weak or deformed children, and the killing of old men and women:

The problems posed by limited resources and old peoples' dependence are sometimes resolved in an extreme way: killing, abandoning, or exposure of the elderly—what anthropologists call gerontocide. Cross-cultural studies show that such treatment is more common than we might suppose. Maxell and Silverman found evidence of gerontocide in a little over 20% of 95 societies in a worldwide sample (Silverman, 1987). Glascock uncovered abandonment of the elderly in 9 of the 41 nonindustrial societies in his sample—and reports of killing old people in 14 of these societies. (Bengtson and Achenbaum, 1993, p. 110)

This kind of thing may seem unfortunate but justifiable among nomads. Sometimes, the elderly just have to be left behind. But we also see elder abandonment in sedentary peoples, like the Hopi of the American southwest:

As long as aged men controlled property rights, held special ceremonial offices, or were powerful medicine men, they were respected. But "the feebler and more useless they become, the more relatives grab what they have, neglect them, and sometimes harshly scold them, even permitting children to play rude jokes on them." Sons might refuse to support their fathers, telling them, "You had your day, you are going to die pretty soon." (Bengtson and Achenbaum, 1993, pp. 108-109)

Whenever such accounts come up at anthropological conferences, there is a certain malaise. Some will blame European contact for the devaluing of human life. Others, however, will present similar facts that often predate the coming of traders or missionaries. I remember one speaker who presented evidence of cannibalism at an Inuit site. This wasn't an isolated case, such as might happen in extreme circumstances of starvation. There seemed to be an accumulation of human bones, of Indian origin, with cut marks on them. The findings were later published:

The remains of at least 35 individuals (women, children, and the elderly) were recovered from the Saunaktuk site (NgTn-1) in the Eskimo Lakes region of the Northwest Territories. Recent interpretations in the Arctic have suggested a mortuary custom resulting in dismemberment, defleshing, chopping, long bone splitting, and scattering of human remains. On the evidence from the Saunaktuk site, we reject this hypothesis. The Saunaktuk remains exhibit five forms of violent trauma indicating torture, mutilation, murder, and cannibalism. Apparently these people were the victims of long-standing animosity between Inuit and Amerindian groups in the Canadian Arctic. (Melbye and Fairgrieve, 1994)

When I talked with the speaker after his presentation, he seemed apprehensive. How would people react?

He needn't have worried. The noble savage is still alive and well. Strangely enough, this kind of thinking has seeped even into the missionary mindset, as I discovered during my last few years at the United Church of Canada. I was surprised to learn just how little our mission work involved teaching of Christian morality:

"Do you talk to these people about the Christian faith?"

"Not unless they specifically request it."
"Do you at least have Christian literature on display?"
"No, we're not allowed to do that."

Things aren't much better in the fundamentalist churches. I remember attending a Pentecostal presentation on "the cause of Third World Poverty." I thought the talk would focus on cultural values. Instead, we were told that the cause is ... lack of infrastructure. The Third World is poor because it doesn't have enough roads, bridges, and buildings.

The modern world has bought so much into the argument of Natural Law that the entire Christian enterprise now looks like a waste of time. There was no need for missionaries to fight barbaric customs, since there were no barbaric customs to be fought. All of that was one big misunderstanding. Christian mission work is now limited to good works, apparently in the belief that all humans share the same moral framework and that it's enough to set a good example. If you act nice, other people will get the message and likewise act nice.

A hazardous assumption

Christianity has been killed by its success. It has so thoroughly imposed its norms of behavior that we now assume them to be human nature. If some people act contrary to those norms, it's because they're "sick" or "deprived." Or perhaps something is misleading us and they're really acting just like everyone else.

For two millennia, the Christian faith has profoundly shaped the culture of European peoples, allowing very little to escape its imprint. This is especially so in attitudes toward the taking of life. Beginning in the 11th century, the Church allied itself with the State to punish murder, which previously had been a private matter to be settled through revenge or compensation. At the height of this war on murder, between 0.5 and 1.0 % of all men of each generation were sentenced to death, and a comparable proportion of offenders died at the scene of the crime or in prison while awaiting trial. Meanwhile, homicide rates plummeted from between 20 and 40 per 100,000 in the late Middle Ages to between 0.5 and 1.0 in the mid-20th century (Eisner, 2001). The pool of violent men dried up until most murders occurred under conditions of jealousy, intoxication, or extreme stress. Yes, people got the message to act nice, but the message was not delivered nicely.

By pacifying social relations, Church and State also created a culture that rewarded men who got ahead through trade and hard work, rather than through force and plunder. It became easier to plan for the future and develop what came to be known as middle-class values: thrift, sobriety, and self-control. Popular tastes changed accordingly, as seen in the decline of cock fighting, bear and bull baiting, and other blood sports (Clark, 2007; Clark, 2009a; Clark, 2009b).

Were these changes in behavior purely cultural? Or was there also a steady removal of violent predispositions from the gene pool? It's only now that a few scholars are beginning to ask such questions, let alone answer them.

Towards a new perspective ...

The idea of Natural Law is true up to a point. All humans have to face certain common problems that have to be solved in more or less the same way. Kinship, for instance, matters in all human societies, at least traditional ones. Marriage and family are likewise universal.

But even these "universals" vary a lot. There are many kinds of kinship systems, including some with relatively weak kinship and a correspondingly stronger sense of individualism. Mating systems likewise vary a lot. Monogamy makes sense in non-tropical societies where the mother cannot feed her children by herself, particularly in winter. It makes less sense where the mother can provide for her children with minimal assistance.

Human societies similarly differ in their treatment of murder. There is a general tendency to limit the taking of human life, but the variability is considerable. In some societies, murder is so rare that instances of it are thought to be pathological. The murderer is said to be "sick." In other societies, every adult male has the right to use violence to settle personal disputes, even to the point of killing. If he abdicates that right, he's no longer a real man.

The same "problem" will thus be solved in different ways in different places. Over time, each society will develop a "solution" that favors the survival and reproduction of certain people with a certain personality type and certain predispositions. So there is no single human nature, any more than a single Natural Law. Instead, there are many human natures with varying degrees of overlap.

... and the take-home message?

While certain notions of right and wrong can apply to all humans, much of what we call "morality" will always be population-dependent. What is moral in one population may not be in another.

Take public nudity, particularly of the female kind. This is less of a problem in places like Finland where polygyny is rare and sexual rivalry among men less intense. It's more of a problem where the polygyny rate is higher but men still have to invest a lot in their offspring. In such a setting, men will be more jealous, more fearful of cuckoldry, and more insistent on measures to ensure exclusive sexual access. Such insistence can lead to extreme practices like sati. More generally, it leads to demands for modesty in female dress.

This is not to condone the dress codes that prevail in some countries, but we should try to understand the circumstances that give rise to them. Above all, there are limits to what we can impose on other societies. While sati has no justification anywhere on this planet, there may be practices that are warranted in some societies but not in others.

References

Aquinas, T. (1265-1274). Summa Theologica, Part I-II (Pars Prima Secundae) From the Complete American Edition, Translated by Fathers of the English Dominican Province, Project Gutenberg

http://www.gutenberg.org/cache/epub/17897/pg17897.html

Bengtson, V.L. and W.A. Achenbaum. (1993).The Changing Contract across Generations, Transaction publ.

Clark, G. (2007). A Farewell to Alms. A Brief Economic History of the World, Princeton: Princeton University Press.

Clark, G. (2009a). The indicted and the wealthy: Surnames, reproductive success, genetic selection and social class in pre-industrial England.

http://www.econ.ucdavis.edu/faculty/gclark/Farewell%20to%20Alms/Clark%20-Surnames.pdf

Clark, G. (2009b). The domestication of man: The social implications of Darwin. ArtefaCTos, 2, 64-80.

http://campus.usal.es/~revistas_trabajo/index.php/artefactos/article/viewFile/5427/5465

Eisner, M. (2001). Modernization, self-control and lethal violence. The long-term dynamics of European homicide rates in theoretical perspective, British Journal of Criminology, 41, 618-638.

http://bjc.oxfordjournals.org/content/41/4/618.short

Melbye, J. and S.I. Fairgrieve. (1994). A massacre and possible cannibalism in the Canadian Arctic: New evidence from the Saunaktuk site (NgTn-1), Arctic Anthropology, 31, 57-77.

http://www.jstor.org/discover/10.2307/40316364?uid=3739448&uid=2&uid=3737720&uid=4&sid=21104564497747

Napier, W. (1851). The History of General Sir Charles Napier's Administration of Scinde: And Campaign in the Cutchee Hills, London: Charles Westerton.

Sati (practice). (2014). Wikipedia

http://en.wikipedia.org/wiki/Sati_(practice)

Tavernier, J-B. (1678).The six voyages of John Baptista Tavernier, London: R.L. and M.P.

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