Rotherham: The search for answers

 

A Bangladeshi youth gang in Tower Hamlets, London. (Source: Wikimedia Commons, Bangali71). Is this the kind of assimilation you had in mind?

 

 

In my last post, I discussed the revelations from Rotherham, England. In a town of some 250,000 people, at least 1,400 school-age girls have been "groomed" for prostitution by organized gangs. Grooming begins with seduction by "lover boys" and ends in abduction, trafficking, and confinement. It is this final stage that apparently explains why some 500 girls were missing from the 15 to 19 age group at the last census.

Two more points. All of the girls are white, and all of the groomers are Pakistani, except for a few Afghans and Roma.

Even before the latest revelations, and even in antiracist circles, there was a growing (though reluctant) awareness that this social problem is disproportionately "Asian," a term that increasingly means Muslim South Asian. The cause, however, seems elusive:

[...] this disparity begs further exploration and, if possible, explanation. Admittedly, this is not an easy job. Complex social issues can rarely be explained in terms of a single factor and moving from correlation to causality is particularly challenging. Nonetheless, in CSE [child sexual exploitation], as with other crimes, observed relationships between race and offending may well be mediated by social, structural or situational factors. Asians, like whites or blacks, do not commit CSE offences because they are Asian, white or black. This lazy, circular logic, verging on quasi-geneticism, would label every Asian adult equally a groomer-in-waiting and fails to address the immediate precipitates of CSE, such as ready access to children and low levels of formal or informal surveillance to constrain deviant behaviour. (Cockbain, 2013)

But if we wish to understand constraints on deviancy, one key variable may be ethnicity, particularly if an ethnic boundary separates the victim from the victimizer. It is precisely within this underdetermined space that such constraints are most likely to break down.

 

The limits to shame

In most of the world's cultures, deviant behavior is kept in check by shaming. A wrongdoing is witnessed by other people, who spread the word to others. The wrongdoers feel shame, knowing that their reputation is now tarnished. In cases of severe wrongdoing, they may have to leave their community.

As a means to keep deviancy in check, shaming has three limitations:

- It cannot control behavior that is not witnessed by anyone other than the wrongdoers themselves.

- It cannot control behavior that is aimed at someone outside one's community.

- Because shame is socially mediated, it is less effective in modern Western societies, where people generally interact as anonymous individuals.

A minority of world cultures supplement shame with another means of behavior control. These cultures, essentially those of Western Europe, rely much more on internal mental mechanisms—guilt and affective empathy—to enforce social rules that have the perceived backing of moral authority. You feel guilt when you break a rule or even merely think about breaking it. No witnesses are necessary, other than the imaginary one inside your mind (Benedict, (1946 [2005]). Similarly, no one tells you to feel empathy when you see another person unjustly suffering. Refusal to act on these feelings can lead to anguish, depression and, ultimately, suicidal ideation (Jadhav, 1996; O'Connor et al.,2007). Guilt and empathy are thus more effective than shame as means to control behavior.

The capacity to feel guilt and empathy varies from one individual to another, the heritability being moderate to high (Chakrabarti and Baron-Cohen, 2013; Daviset al., 1994). There has thus been a potential for gene-culture co-evolution, i.e., guilt cultures may have selected for individuals with a higher capacity for guilt and empathy. Even if the behavioral differences between guilt cultures and shame cultures are entirely softwired, the consequences are nonetheless real.

 

From shame culture to guilt culture

Immigration is not just a movement from one place to another. It is also a movement from one culture to another. In Britain in general, it has largely involved people coming to a guilt culture from various shame cultures in South Asia, the Caribbean, and elsewhere. 

In South Asia, be it Hindu India or Muslim Pakistan and Bangladesh, shaming provides a woman with no protection from unwanted sexual advances once she ventures beyond her own neighborhood:

The prime danger is from male strangers who are seen as liable to take advantage of an unescorted woman. Such strangers, as a category, are presumed to be sexually predatory and always ready to pounce. Some young men (and some not so young) reinforce that notion in town streets and in buses through the common practice known in Indian English as "eve-teasing." In the anonymity of the streets, some men who would spring fiercely to the defense of the women of their own families, leer, hoot, pinch, and make sexually pointed remarks at passing women whom they do not know and who do not know them [...]. However, they rarely act that way in their own mohalla, neighbourhood. (Mandelbaum, 1993, pp. 9-10)

 

In a shame culture, a wrongdoing is not shameful if the witnesses are from outside one's "moral community." Often, there is no clear boundary between outside and inside; the moral community simply fades away as one goes farther away from the people one knows. The boundary is much more clear-cut if it coincides with a difference in religion. When Moroccan and Turkish "lover boys" were interviewed in Amsterdam, it was found that their identity as Muslims strongly influenced how they perceived their victims:

One pimp told us that it was not only easier to get Dutch girls into prostitution, but that they were worth less than other girls and therefore deserved to end up as prostitutes. 'Culturally and religiously, a Dutch girl is little more than a pig to a loverboy. She's nothing, she's of no value. When that's what you're thinking, you can completely block out your emotions.' As mentioned, most loverboys were reluctant to manipulate the daughters of immigrants into prostitution, especially when it came to girls leading a pious life. 'We are obligated to treat Moroccan girls as we would treat our own sisters; we can't treat them as rags. You can't just make a Moroccan girl work for you. (...) Listen, when a Moroccan girl wants to do it, that's different. But if she goes to school and wears a headscarf, it's just not right'. (Van San and Bovenkerk,2013)

Muslim girls were not avoided, however, solely out of loyalty to Islam.

They [lover boys] had a lot more trouble with the daughters of immigrants, 'because those families have respect for each other.' In their view, this was not the case with Dutch girls: 'Dutch girls really are the easiest. (...) Nowadays, there are girls of thirteen or fourteen years old who have already lost their virginity. They go to clubs and discos and stay away from home for a whole weekend. They want to go out, they want new clothes, but they don't have the money. When a loverboy comes along and the girl spots him and he seems like a nice boy, things happen... Meeting a loverboy is like hitting the jackpot, you know what I mean?' (Van San and Bovenkerk, 2013)

 

The lover boy, an adaptation to female mate scarcity?

Keep in mind that Muslims are not the only group to be overrepresented in this social niche. Among the lover boys interviewed by Van San and Bovenkerk (2013), half were Muslims (Moroccans, Turks) and half were from the Dutch West Indies. In the British OCCE study on child sexual exploitation in gangs and groups, around 24% of the suspects were neither white nor Asian, being probably blacks of Caribbean or African origin (Cockbain, 2013).

Thus, in addition to the difference of religion, and the resulting moral boundary between victim and victimizer, there seems to be another factor in the genesis of lover boys. This factor is nonreligious and would apply not only to the Muslim world but also to sub-Saharan Africa and its diaspora. In both culture areas, many young men are inevitably shut out of the marriage market because of excess female mortality and high polygyny rates (5-10% in the Muslim world and 20-40% in sub-Saharan Africa) (D'Souza and Chen, 1980; Fuse and Crenshaw, 2006; Goody, 1973, pp. 175-190; Pebley and Mbugua, 1989). There may have therefore been selection for young men who can exploit sexual opportunities, if and when they arise, via specific personality traits.

Alvergne et al. (2009, 2010a, 2010b) explored the relationship between male personality and sexual competition in the high-polygyny environment of Senegal. There was no correlation among Senegalese men between mating success and most personality traits, i.e., neuroticism, openness, and agreeableness. There was a strong correlation, however, with extraversion, defined as "pro-social behavior which reflects sociability, assertiveness, activity, dominance and positive emotions." Men with above-medium extraversion were 40% more likely to have more than one wife than those with below-medium extraversion, after controlling for age. Furthermore, this personality trait correlated with higher testosterone levels. It thus seems to be part of the male toolkit for mating success in a high-polygyny environment.

From antiracism to anti-Islamism

It’s one thing to look for answers. In this, anthropology can offer some insights. It’s quite another to translate the explanation into applicable solutions. To go from one to the other may involve surmounting mental and political obstacles.

First, most Britons have been living in denial. Few wish to believe, at least openly, that organized gangs are preying on school-age girls. Fewer wish to believe that the gangs are overwhelmingly non-white and largely Muslim. And even fewer wish to believe the extent of the problem: perhaps one in ten of Rotherham's white families, if not more. It all sounds like vicious propaganda that only ugly hate-filled people could believe.

Yet it's true. So what comes next? Many disillusioned antiracists will likely end up seeing Islam, and not racism, as the problem. The solution will therefore be to secularize Muslim culture and replace it with an assimilated, Westernized version, like modern Christianity.

Politically, anti-Islamism is attractive. It has the merit of framing the problem in ideological and not racial terms. It is also likely to win over much of the political elite, particularly those who have backed previous military interventions in the Muslim world and would like to see more.

But will it work? Let's assume anti-Islamists are not sidetracked into cheerleading a new round of foreign interventions "to get to the root of the problem." Let's also assume the focus is on assimilating Muslims living in Britain. Unfortunately, not only will this approach fail to solve the problem, it will actually make things worse.

In a Western context, assimilation does not mean giving up the restraints of one culture and taking on those of another. It means the first but not the second. Immigrants leave an environment where behavior is restrained mainly by external controls (shaming, family discipline, community surveillance) and they enter one where behavior is restrained mainly by internal controls (guilt, empathy). To the extent that assimilation happens, external social controls will weaken and may even disappear, but they will not be replaced by internal mental controls. There is no known way to give people a greater capacity for guilt and empathy than what they already have. No such psychotherapy exists. This is true even if we assume that population differences in these two traits are due solely to cultural conditioning, and not to inborn tendencies.

Assimilation is already making things worse by dissolving traditional restraints on behavior and leaving nothing in their place. Keep in mind that grooming is largely absent from the 1st generation of Britain's Pakistani community. It's much more present among young men of the 2nd and 3rd generations. They are very much into contemporary Western culture and are freely borrowing those elements that appeal to them the most:

Taj refers to '. . . the growing popularity of the "gangsta" fashion affected by local youths as they adopt the clothing and elements of the attitudes of disenchanted urban American youth gangs' (1996, p.4). Khan describes 'This new youth Pakistani "street culture" [as] male dominated and highly macho' (1997, p.18), linking drug dependency among young Pakistani men with their involvement in violent crime, including prostitution. (Macey, 1999)

Accusations of "racism" likewise reflect an insider's view of Western society and its weak points:

When I asked about racial harassment by the police, the women reacted with amusement. One of them said: 'Well, they would, wouldn't they? After all, they know it's these lads who're doing the dealing'. Another stated that 'the lads' had planned to accuse the police of racism because they had found this an effective weapon against authority in the past. In sum, while it seems unlikely that the Bradford police force contains no racists in its ranks, to 'explain' Pakistani male violence solely, or even mainly, as a reaction to police racism might well be over-simplified. (Macey, 1999)

The result is an unstable hybrid culture that is as foreign to 1st generation immigrants as it is to native Britons:

These young men have constructed an ethnic and religious identity which goes beyond hybridity in containing a high level of contradiction — a contradiction which is highly functional in its facilitation of dual standards, hypocrisy and legitimation, which are used as resources to maintain power over women. These aspects of male behaviour and their control function are clearly recognized, and resented, by young Pakistani women. One example quoted to me is the men's involvement in 'discos, drink, drugs and white women', while simultaneously putting pressure (to the point of harassment and threatened violence) on Pakistani women to stay at home and behave as 'good' Muslim women. (Macey,1999)

 

Conclusion

Yes, the whole issue is a messy ball of wax. The worst part is the reluctance not just to discuss it but even to think it through, the result being that the proposed solutions have only a vague connection to the actual problem, which is neither "racism" nor "Islamism."

What then is the problem? It's the mass migration of certain communities from an environment where behavior is subject to certain checks and balances to one where these are virtually absent.

Why do you think Pakistani parents want their daughters to wear headscarves or at least dress modestly? Are they being slaves to hidebound custom? Or is it because they come from a society where many single men are, in fact, sexual predators?

And that’s just one aspect of a much larger problem. Humans have adapted to local circumstances in many different ways, and these adaptations involve mental traits with moderate to high heritability. Things like time orientation, monotony avoidance, anger threshold, strength and nature of the sexual bond, and so forth. Such differences keep us from becoming interchangeable units in a global community. Each human and each community is a product of adaptations to specific circumstances, and what works in one set of circumstances may not work so well in another.

References 

Alvergne, A., M. Jokela, C. Faurie, and V. Lummaa. (2010a). Personality and testosterone in men from a high-fertility population, Personality and Individual Differences, 49, 840-844.

http://www.huli.group.shef.ac.uk/alvergne2010persinddiff.pdf 

Alvergne, A., M. Jokela, and V. Lummaa. (2010b). Personality and reproductive success in a high-fertility human population, Proceedings of the National Academy of Sciences, 107, 11745-11750.

http://huli.group.shef.ac.uk/alvergne_PNAS.pdf 

Alvergne, A., C. Faurie, and M. Raymond. (2009). Variation in testosterone levels and male reproductive effort: Insight from a polygynous human population, Hormones and Behavior, 56, 491-497.

http://evolutionhumaine.fr/michel/publis/pdf/alvergne_2009_hormones_behavior.pdf

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  

Cockbain, E. (2013). Grooming and the 'Asian sex gang predator': the construction of a racial crime threat, Race & Class, 54, 22-32.

http://rac.sagepub.com/content/54/4/22.short  

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

http://onlinelibrary.wiley.com/doi/10.1111/j.1467-6494.1994.tb00302.x/abstract 

D'Souza, S. and L.C. Chen. (1980). Sex differentials in mortality in rural Bangladesh, Population and Development Review, 6, 257-270.

http://www.jstor.org/discover/10.2307/1972730?uid=3739448&uid=2&uid=3737720&uid=4&sid=21104683180073  

Fuse K. and E.M. Crenshaw. (2006). Gender imbalance in infant mortality: a cross-national study of social structure and female infanticide, Social Science and Medicine, 62, 360-374.

http://www.sciencedirect.com/science/article/pii/S0277953605002881

Goody, J. (1973). The Character of Kinship, Cambridge: Cambridge University Press. 

Jay, A. (2014). Independent Inquiry into Child Sexual Exploitation in Rotherham 1997-2013

http://www.rotherham.gov.uk/downloads/file/1407/independent_inquiry_cse_in_rotherham  

Jadhav, S. (1996). The cultural origins of Western depression, International Journal of Social Psychiatry, 42, 269-286.

http://isp.sagepub.com/content/42/4/269.short 

Macey, M. (1999). Class, gender and religious influences on changing patterns of Pakistani Muslim male violence in Bradford, Ethnic and Racial Studies, 22, 5, 845-866

http://www.tandfonline.com/doi/abs/10.1080/014198799329288#.VBOnH-kg_cs

Mandelbaum, D.G. (1993). Women's Seclusion and Men's Honor: Sex Roles in North India, Bangladesh, and Pakistan, University of Arizona Press. 

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  

Pebley, A. R., and W. Mbugua. (1989). Polygyny and Fertility in Sub-Saharan Africa. In R. J. Lesthaeghe (ed.), Reproduction and Social Organization in Sub-Saharan Africa, Berkeley: University of California Press, pp. 338-364.

http://www.popline.org/node/359257 

Van San, M. and F. Bovenkerk. (2013). Secret seducers. True tale of pimps in the red light district of Amsterdam, Crime, Law and Social Change, 60, 67-80.

http://link.springer.com/article/10.1007/s10611-013-9436-z

Eye color, face shape, and perceived personality traits

Averaged face of blue-eyed male subjects (left). Averaged face of brown-eyed male subjects (right). Czech population. (Kleisner et al., 2010)

Karel Kleisner’s team is continuing its work on eye color, face shape, and perceived personality traits:

We tested whether eye color influences perception of trustworthiness. Facial photographs of 40 female and 40 male students were rated for perceived trustworthiness. Eye color had a significant effect, the brown-eyed faces being perceived as more trustworthy than the blue-eyed ones. Geometric morphometrics, however, revealed significant correlations between eye color and face shape. Thus, face shape likewise had a significant effect on perceived trustworthiness but only for male faces, the effect for female faces not being significant. To determine whether perception of trustworthiness was being influenced primarily by eye color or by face shape, we recolored the eyes on the same male facial photos and repeated the test procedure. Eye color now had no effect on perceived trustworthiness. We concluded that although the brown-eyed faces were perceived as more trustworthy than the blue-eyed ones, it was not brown eye color per se that caused the stronger perception of trustworthiness but rather the facial features associated with brown eyes. (Kleisner et al., 2013)

Eye color is thus associated in males with a specific face shape, even when the men are of the same ethnic background, i.e., Czechs in this study. Face shape is more robust if eye color is brown and less so if eye color is blue. Furthermore, a robust male face seems to evoke an image of dominance and trustworthiness, whereas a less robust one is perceived as being less dominant and less trustworthy.

When the first study came out, in 2010, I thought this association between eye color and face shape was due to ethnic admixture, i.e., some of the brown-eyed participants had Jewish or Roma ancestry. If this were so, however, face shape would vary to a greater degree among the brown-eyed participants than among the blue-eyed ones, yet the current study found no such difference. The “ethnic admixture” explanation also fails to explain why blue eyes are associated with a less robust face in men but not in women.

Are European facial features actually female facial features?

There thus seems to be a linkage between eye color and face shape. This finding is consistent with findings for other European physical traits, especially bright or colorful facial features. These European traits—white skin, multi-colored hair, multi-colored eyes, and a less robust face shape—are actually female traits. They seem to be due to a selection pressure that first acted on early European women and then spilled over on to early European men. This phenotypic change affected both sexes because the traits in question are at most mildly sex-linked.

The direction of sex linkage is consistent with the above model of selection. Hair color became polymorphic in Europeans through the emergence of brighter hues, but this evolutionary change is most pronounced in European women. According to a twin study, hair is lighter in women than in men, with red hair being especially more common. Women also show more variation in hair color (Shekar et al., 2008). Again, this evolutionary trend seems to have been driven by European women with European men tagging along.

There is also unpublished evidence that “European” hair and eye colors (i.e., non-black hair and non-brown eyes) are associated with a higher degree of estrogenization before birth, as indicated by digit ratio. This prenatal estrogenization might also favor a more feminine face shape. Face shape would thus correlate with eye color because of a shared determining factor: the degree to which the fetus is estrogenized or androgenized in the womb. Such a correlation would have been stronger in the male participants than in the female participants because estrogenization is overdetermined in females, i.e., almost all girls are exposed to enough estrogen in the womb to feminize their face shape, whereas this level of estrogenization would be reached only in blue-eyed boys.

In one respect, however, the blue-eyed face looks less feminized, the chin being relatively narrower and longer. It might be that this is what happens when the trajectory of facial development is initially programmed for a feminine appearance before birth but is not supported by circulating estrogen later in life.

References

Frost, P. (2008). Sexual selection and human geographic variation, Special Issue: Proceedings of the 2nd Annual Meeting of the NorthEastern Evolutionary Psychology Society. Journal of Social, Evolutionary, and Cultural Psychology, 2(4),169-191. http://137.140.1.71/jsec/articles/volume2/issue4/NEEPSfrost.pdf

Frost, P. (2006). European hair and eye color - A case of frequency-dependent sexual selection? Evolution and Human Behavior, 27, 85-103 http://www.sciencedirect.com/science/journal/10905138

Kleisner, K., L. Priplatova, P. Frost, & J. Flegr. (2013). Trustworthy-looking face meets brown eyes, PLoS One,  8(1): e53285. doi:10.1371/journal.pone.0053285

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0053285

Kleisner, K., T. Kočnar, A. Rubešova, and J. Flegr. (2010). Eye color predicts but does not directly influence perceived dominance in men, Personality and Individual Differences, 49, 59–64.

Shekar, S.N., D.L. Duffy, T. Frudakis, G.W. Montgomery, M.R. James, R.A. Sturm, & N.G. Martin. (2008). Spectrophotometric methods for quantifying pigmentation in human hair—Influence of MC1R genotype and environment. Photochemistry and Photobiology, 84, 719–726.

 

Human nature or human natures?

A new article of mine has just appeared in the journal Futures. All comments are welcome.

Abstract

Most evolutionary psychologists share a belief in one key concept: the environment of evolutionary adaptedness (EEA), i.e., the ancestral environment that shaped the heritable mental and behavioral traits of present-day humans. It is usually placed in the African savannah of the Pleistocene, long before our ancestors began to spread to other continents some fifty thousand years ago. Thus, later environments have not given rise to new traits through genetic evolution.

This belief rests on two arguments: 1) such traits are complex and therefore evolve too slowly to have substantially changed over the past fifty thousand years; 2) because the same time frame has seen our species diversify into many environments, recent traits should tend to be environment-specific and hence population-specific, yet such specificity seems inconsistent with the high genetic overlap among human populations. Both arguments are weaker than they seem. New complex traits can arise over a relatively short time through additions, deletions, or modifications to existing complex traits, and genetic overlap can be considerable even between species that are morphologically, behaviorally, and physiologically distinct.

There is thus no conceptual barrier to the existence of EEAs in post-Pleistocene times. Such a paradigm could shed light on such research topics as the visual word form area, reproductive strategy, predisposition to violence among young men, and personality traits. Eventually, a multi-EEA model may dominate evolutionary psychology, perhaps after an interim period of accommodation with the current model.

Reference

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

Extraversion: a tool for mating success

Extraversion is part of the male toolkit for mating success. It is especially useful in societies where a high incidence of polygyny means too many men must compete for too few women.

As a single man, I would spend close to $3,000 a year on dating. And that didn’t include things like buying a sportier-looking car. My behavior was also higher risk, in large part to impress women and show how ‘edgy’ I could be.

The mating game is costly. A British study found that men improve their sexual access to women at the cost of increased risk of hospitalization for accident or illness (Nettle 2005). There is thus a trade-off. If you invest more effort in chasing women, less is left over for taking care of yourself and any children you’ve fathered. You also risk early death.

The trade-off varies from one society to another. For a man, the mating game is less costly if the woman can provide for herself and her children with little male assistance. The cost may even be negative if she also provides for her man.

In such societies, it is in a man’s reproductive interest to mate with as many women as possible. The result? A ‘tragedy of the commons’ where the pursuit of self-interest ends up harming society as a whole. There won’t be enough women to go around, and many men will go a long time without a mate, or never find one at all.

This has long been the case with simple ‘horticultural’ societies in the tropical zone. The women feed themselves and their children with minimal male assistance because they can grow food year-round. And this food production is not appropriated by a State or a land-owning class.

Such societies remain simple in large part because intense sexual competition keeps them from evolving into more complex entities. The surplus males stir up endless conflict, if only because their sole access to women is through warfare, i.e., rape and abduction. There can never be pacification and, therefore, the formation of larger, more advanced societies.

How men and women adapt to high-polygyny environments

A high incidence of polygyny favors men with a different toolkit of physical and mental traits. Some personality traits, for instance, will be more advantageous than others. Such is the finding of a series of studies from rural Senegal, where 48% of men over 40 are polygynous.

Men

Alvergne et al. (2009, 2010a, 2010b) found no correlation among Senegalese men between mating success and most personality traits, i.e., neuroticism, openness, and agreeableness. One trait, however, showed a strong correlation. This was extraversion, defined as “pro-social behavior which reflects sociability, assertiveness, activity, dominance and positive emotions.” Men with above-medium extraversion were 40% more likely to have more than one wife than those with below-medium extraversion, after controlling for age. Furthermore, this personality trait correlated with higher testosterone levels. Such a linkage suggests that extraversion is part of the male toolkit for mating success in a high-polygyny environment.

Of course, it may be that the relation of cause and effect is indirect. Extraversion helps men accumulate wealth, and wealthy men can afford to take second or third wives. Nonetheless, the correlation remained significant even after the researchers controlled for social class

Women

Among Senegalese women, reproductive success correlated with neuroticism, i.e., a tendency “to be anxious, depressive, and moody.” Women with above-medium neuroticism had 12% more children than those with below-medium neuroticism, after controlling for age and marital rank. This personality trait may thus be part of the female toolkit for infant survival in an environment where women are almost solely responsible for parenting.

Could the cause and effect run in the other direction? Perhaps having more children makes a woman more neurotic. Yet neuroticism did not increase with age, whereas the number of children did. Furthermore, the correlation was stronger among rich women, who presumably had less reason to worry about child care.

Inter-individual variation

On average, the Senegalese men were more oriented to polygyny and extraversion, but there was significant variation. Some seemed to be more monogamous and introverted.

Perhaps all human populations display this sort of variation in reproductive strategy, the differences among them being one of degree than of kind. Indeed, statistical differences can easily develop among human populations because the raw material for gene-culture co-evolution is already available. There is no need to wait for new mutations to come into existence.

Inter-population variation

What do the authors say about differences among human populations? They initially state, “Men in the present study had lower T [testosterone] levels than has been recorded for men from western societies using similar saliva assays” (Alvergne et al. 2009). Later on, in reviewing the literature, they qualify this statement:

It is worthy of note that inter-population differences in T levels were found to be more pronounced for young men (15-30 years) than for older men (45-60 years) (Ellison, 2003). The authors conclude that the differences between populations in patterns of T decline with age result from variations in peak levels during young adulthood and are thus highly dependent on the reproductive physiology of young males.
(Alvergne et al. 2009)

The decline in T levels with age is sharper among polygynous Senegalese men than among monogamous Senegalese men. In short, higher T levels in young adulthood mean lower ones later in life:

When men get older than 50, a reversed pattern is observed, with polygynously married men having lower T levels than monogamously married men.
(Alvergne et al. 2009).

This may account for the authors’ initial statement that T levels were lower in Senegalese men than in Western men. The Senegalese subjects were 38.3 years old on average.

A similar reversal with age has been noted in U.S. studies. African Americans have a clear testosterone advantage over Euro-Americans only from puberty to about 24 years of age. This advantage then shrinks and eventually disappears at some point during the 30s (1). The pattern then seems to reverse at older ages (Ellis & Nyborg 1992; Gapstur et al. 2002; Nyborg 1994, pp. 111-113; Ross et al. 1986; Ross et al. 1992; Tsai et al. 2006; Winters et al. 2001).

No one really knows why. We know that too much testosterone early in life causes long-term harm, e.g., increased risk of prostate cancer. Perhaps there is also degradation of the body’s capacity to produce testosterone.

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

A hen is an egg’s way to make another egg. I remember being told that as a child. Perhaps we should now say: A man is a sperm’s way to make more sperm.

H/T to Tod.

Note

1. Tsai et al. (2006) found that baseline levels of both total and bioavailable testosterone were significantly higher in African Americans than in Euro-Americans with a median age of 33-34. Ellis and Nyborg (1992) found that African Americans had a slight but still significant (p=0.028) testosterone advantage over Euro-Americans among subjects with a median age of 38. It is difficult to identify the ‘tipping point’ because both studies used pools of subjects with wide age ranges.

References

Alvergne, A., M. Jokela, C. Faurie, and V. Lummaa. (2010). Personality and testosterone in men from a high-fertility population, Personality and Individual Differences, 49, 840-844.

Alvergne, A., M. Jokela, and V. Lummaa. (2010). Personality and reproductive success in a high-fertility human population, Proceedings of the National Academy of Sciences, 107, 11745-11750.

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