Genetic pacification of Western Europeans (?)

Evolutionary Psychology www.epjournal.net – 2015. 13(1): 230-243

Western Europe, State Formation, and Genetic Pacification

Peter Frost, Henry C. Harpending

Through its monopoly on violence, the State tends to pacify social relations. Such pacification proceeded slowly in Western Europe between the 5th and 11th centuries, being hindered by the rudimentary nature of law enforcement, the belief in a man’s right to settle personal disputes as he saw fit, and the Church’s opposition to the death penalty. These hindrances began to dissolve in the 11th century with a consensus by Church and State that the wicked should be punished so that the good may live in peace. Courts imposed the death penalty more and more often and, by the late Middle Ages, were condemning to death between 0.5 and 1.0% of all men of each generation, with perhaps just as many offenders dying at the scene of the crime or in prison while awaiting trial. Meanwhile, the homicide rate plummeted from the 14th century to the 20th. The pool of violent men dried up until most murders occurred under conditions of jealousy, intoxication, or extreme stress. The decline in personal violence is usually attributed to harsher punishment and the longer-term effects of cultural conditioning. It may also be, however, that this new cultural environment selected against propensities for violence.

Link (pdf)

Huge differences in personality between men and women

From the paper's conclusion:

In conclusion, we believe we made it clear that the true extent of sex differences in human personality has been consistently underestimated. While our current estimate represents a substantial improvement on the existing literature, we urge researchers to replicate this type of analysis with other datasets and different personality measures. An especially critical task will be to compare self-reported personality with observer ratings and other, more objective evaluation methods. Of course, the methodological guidelines presented in this paper can and should be applied to domains of individual differences other than personality, including vocational interests, cognitive abilities, creativity, and so forth. Moreover, the pattern of global sex differences in these domains may help elucidate the meaning and generality of the broad dimension of individual differences known as “masculinity-femininity” [11]. In this way, it will be possible to build a solid foundation for the scientific study of psychological sex differences and their biological and cultural origins.

From the press release:

The researchers used personality measurements from more than 10,000 people, approximately half men and half women. The personality test included 15 personality scales, including such traits as warmth, sensitivity, and perfectionism. When comparing men's and women's overall personality profiles, which take multiple traits into account, very large differences between the sexes became apparent, even though differences look much smaller when each trait is considered separately. However, the study indicates that previous methods to measure such differences have been inadequate, both because they focused on one trait at a time and because they failed to correct for measurement error.

PLoS ONE 7(1): e29265. doi:10.1371/journal.pone.0029265

The Distance Between Mars and Venus: Measuring Global Sex Differences in Personality

Marco Del Giudice et al.

Abstract

Background

Sex differences in personality are believed to be comparatively small. However, research in this area has suffered from significant methodological limitations. We advance a set of guidelines for overcoming those limitations: (a) measure personality with a higher resolution than that afforded by the Big Five; (b) estimate sex differences on latent factors; and (c) assess global sex differences with multivariate effect sizes. We then apply these guidelines to a large, representative adult sample, and obtain what is presently the best estimate of global sex differences in personality.

Methodology/Principal Findings

Personality measures were obtained from a large US sample (N = 10,261) with the 16PF Questionnaire. Multigroup latent variable modeling was used to estimate sex differences on individual personality dimensions, which were then aggregated to yield a multivariate effect size (Mahalanobis D). We found a global effect size D = 2.71, corresponding to an overlap of only 10% between the male and female distributions. Even excluding the factor showing the largest univariate ES, the global effect size was D = 1.71 (24% overlap). These are extremely large differences by psychological standards.

Significance

The idea that there are only minor differences between the personality profiles of males and females should be rejected as based on inadequate methodology.

Link

Brain structure and Personality Big Five

From the paper:

The associations of personality traits with volume in predicted brain regions were generally consistent with the hypothesis that larger brain tissue volume is associated with increased function (with the exception of the negative association of Agreeableness with volume in superior temporal sulcus). For example, Neuroticism was positively associated with volume in a region of the cingulate linked to the detection of error and response to pain, both of which increase with Neuroticism. Also, Neuroticism was negatively associated with volume in a region of PFC associated with emotional regulation, which decreases with Neuroticism. However, our findings do not provide definitive evidence to allow generalizations about the relation of volume to function, and further research should target this question directly.

Psychological Science doi:10.1177/0956797610370159

Testing Predictions From Personality Neuroscience
Brain Structure and the Big Five

Colin G. DeYoung et al.

Abstract

We used a new theory of the biological basis of the Big Five personality traits to generate hypotheses about the association of each trait with the volume of different brain regions. Controlling for age, sex, and whole-brain volume, results from structural magnetic resonance imaging of 116 healthy adults supported our hypotheses for four of the five traits: Extraversion, Neuroticism, Agreeableness, and Conscientiousness. Extraversion covaried with volume of medial orbitofrontal cortex, a brain region involved in processing reward information. Neuroticism covaried with volume of brain regions associated with threat, punishment, and negative affect. Agreeableness covaried with volume in regions that process information about the intentions and mental states of other individuals. Conscientiousness covaried with volume in lateral prefrontal cortex, a region involved in planning and the voluntary control of behavior. These findings support our biologically based, explanatory model of the Big Five and demonstrate the potential of personality neuroscience (i.e., the systematic study of individual differences in personality using neuroscience methods) as a discipline.

Link (pdf)

Social perception of obesity

Caption for figure:

1. Lean (L - narrow shoulders, thin torso and extremities, knee and elbow joints thicker than thy and arm diameter). 2. Muscular (M – Broad shoulders, curved extremities, chest and abdominal muscles shown, thy and arm diameters greater than knee and elbow joints). 3. Slightly fat and feminine (F – rounded shoulders, cylindrical extremities). Each of the three body forms was represented with (designated by +) and without (−) abdominal obesity as shown in rows. The sequence of these figures was randomized during the test and the figures were labeled serially by alphabets.

From the paper:

hysical characters were associated with the appropriate body forms as expected. The physical traits strong, rough and tough and physically aggressive were associated with the muscular non-obese [M−] figure. Lethargic was associated with F+. Disease prone was significantly associated with L− on the one hand and F+ on the other indicating that people negatively associate both the extremes with health. The trait swift was also strongly associated with L−. The traits that are not obviously physical were also strongly associated with certain body forms. Brave, conscious about looks, influential, dominating, status conscious, modern and confident were associated with M−; physical risk avoider, money minded, political, rich, stupid, selfish and greedy were associated most strongly with F+; friendly, intelligent, methodical, business risk avoider, successful, loving, kind, and honest were associated with F−; and L− was the commonest choice for swift, physical risk avoider, talkative and the trait depressed was associated with L+ [table 1].

Link to Table 1.

PLoS ONE doi: 10.1371/journal.pone.0003187

Obesity as a Perceived Social Signal

Manasee Mankar et al.

Abstract

Fat accumulation has been classically considered as a means of energy storage. Obese people are theorized as metabolically ‘thrifty’, saving energy during times of food abundance. However, recent research has highlighted many neuro-behavioral and social aspects of obesity, with a suggestion that obesity, abdominal obesity in particular, may have evolved as a social signal. We tested here whether body proportions, and abdominal obesity in particular, are perceived as signals revealing personality traits. Faceless drawings of three male body forms namely lean, muscular and feminine, each with and without abdominal obesity were shown in a randomized order to a group of 222 respondents. A list of 30 different adjectives or short descriptions of personality traits was given to each respondent and they were asked to allocate the most appropriate figure to each of them independently. The traits included those directly related to physique, those related to nature, attitude and moral character and also those related to social status. For 29 out of the 30 adjectives people consistently attributed specific body forms. Based on common choices, the 30 traits could be clustered into distinct ‘personalities’ which were strongly associated with particular body forms. A centrally obese figure was perceived as “lethargic, greedy, political, money-minded, selfish and rich”. The results show that body proportions are perceived to reflect personality traits and this raises the possibility that in addition to energy storage, social selection may have played some role in shaping the biology of obesity.

Link

AVPR1A and pair bonding in humans

From the press release:

Hasse Walum and his colleagues made use of data from The Twin and Offspring Study in Sweden, which includes over 550 twins and their partners or spouses. The gene under study codes for one of the receptors for vasopressin, a hormone found in the brains of most mammals. The team found that men who carry one or two copies of a variant of this gene  allele 334  often behave differently in relationships than men who lack this gene variant.

The incidence of allele 334 was statistically linked to how strong a bond a man felt he had with his partner. Men who had two copies of allele 334 were also twice as likely to have had a marital or relational crisis in the past year than those who lacked the gene variant. There was also a correlation between the mens gene variant and what their respective partners thought about their relationship.

The same gene was previously implicated in Creative Dance personality. Gene Expression has more.

PNAS doi: 10.1073/pnas.0803081105

Genetic variation in the vasopressin receptor 1a gene (AVPR1A) associates with pair-bonding behavior in humans

Hasse Walum et al.

Abstract

Pair-bonding has been suggested to be a critical factor in the evolutionary development of the social brain. The brain neuropeptide arginine vasopressin (AVP) exerts an important influence on pair-bonding behavior in voles. There is a strong association between a polymorphic repeat sequence in the 5′ flanking region of the gene (avpr1a) encoding one of the AVP receptor subtypes (V1aR), and proneness for monogamous behavior in males of this species. It is not yet known whether similar mechanisms are important also for human pair-bonding. Here, we report an association between one of the human AVPR1A repeat polymorphisms (RS3) and traits reflecting pair-bonding behavior in men, including partner bonding, perceived marital problems, and marital status, and show that the RS3 genotype of the males also affects marital quality as perceived by their spouses. These results suggest an association between a single gene and pair-bonding behavior in humans, and indicate that the well characterized influence of AVP on pair-bonding in voles may be of relevance also for humans.

Link

Preferred traits across nations and sexual orientations

I will try to get a hold of this study to comment further. The finding that "heterosexual more than homosexual participants assigned importance to religion, fondness for children, and parenting abilities" should give pause to those who claim that heterosexuals and homosexuals are equally likely to make good parents.

Arch Sex Behav. 2007 Mar 23; [Epub ahead of print]

The Preferred Traits of Mates in a Cross-National Study of Heterosexual and Homosexual Men and Women: An Examination of Biological and Cultural Influences.

Lippa RA.

Department of Psychology, California State University, Fullerton, California, 92834, USA, rlippa@fullerton.edu.

BBC Internet survey participants (119,733 men and 98,462 women) chose from a list of 23 traits those they considered first, second, and third most important in a relationship partner. Across all participants, the traits ranked most important were: intelligence, humor, honesty, kindness, overall good looks, face attractiveness, values, communication skills, and dependability. On average, men ranked good looks and facial attractiveness more important than women did (d = 0.55 and 0.36, respectively), whereas women ranked honesty, humor, kindness, and dependability more important than men did (ds = 0.23, 0.22, 0.18, and 0.15). Sexual orientation differences were smaller than sex differences in trait rankings, but some were meaningful; for example, heterosexual more than homosexual participants assigned importance to religion, fondness for children, and parenting abilities. Multidimensional scaling analyses showed that trait preference profiles clustered by participant sex, not by sexual orientation, and by sex more than by nationality. Sex-by-nation ANOVAs of individuals' trait rankings showed that sex differences in rankings of attractiveness, but not of character traits, were extremely consistent across 53 nations and that nation main effects and sex-by-nation interactions were stronger for character traits than for physical attractiveness. United Nations indices of gender equality correlated, across nations, with men's and women's rankings of character traits but not with their rankings of physical attractiveness. These results suggest that cultural factors had a relatively greater impact on men's and women's rankings of character traits, whereas biological factors had a relatively greater impact on men's and women's rankings of physical attractiveness.

Link

Happy Danes

Why are Danes the world's happiest nation?

Earlier this year, Denmark came top in a world map of happiness (the UK ranked 41st out of 178 nations). And for more than 30 years it has ranked first in European satisfaction surveys. So what makes Danes so content?

Researchers in this week's Christmas issue of the BMJ decided to find out why life satisfaction in Denmark substantially exceeds that in Sweden and Finland, the two countries most similar to Denmark.

Their hypotheses range from the unlikely (hair colour, genes, food and language) to the more plausible, such as family life, health and a prosperous economy.

However, their analysis points to two explanatory factors. Firstly, winning the 1992 European Football Championship put Danes in such a state of euphoria that the country has not been the same since. This may explain the high level of life satisfaction in Denmark after 1992, they write.

Secondly, while Danes are very satisfied, their expectations for the coming year are rather low. In contrast, Italy and Greece, which rank low on life satisfaction, rank high on expectations for the year to come, together with Swedes and Finns.

The causes of the stolid depth of Danish wellbeing are undoubtedly multifactorial, they say. The Danish football triumph of 1992 has had a lasting impact, but the satisfaction of the Danes began well before 1992, albeit at a more moderate level. The key factor that explains this, and that differentiates Danes from Swedes and Finns, seems to be that Danes have consistently low (and realistic) expectations for the year to come.

So the key to happiness may lie in the fact that if you lower your expectations enough you might feel a bit better next Christmas, they conclude.

Personality traits of voters for US presidential elections

Personality and Individual Differences (Article in Press)

Voters’ personality traits in presidential elections

Claudio Barbaranelli et al.

Abstract

Personality measures of more than 6000 US electors on the Big Five Factors have been collected on the Web through a Web site designed to assess their personality. By means of structural equation modeling the impact of personality factors as well as of demographic variables, such as age and sex, on voting intentions on the forthcoming US presidential elections was investigated. Personality variables accounted for 16% of variance of voting intentions, while gender and age accounted for no more than 3%. High Agreeableness and Openness were predictive of intention to vote for Kerry, while all high Energy, Conscientiousness and Emotional Stability were predictive of intention to vote for Bush. Results are consistent with previous research conducted in a different country, using a different language.

Link

Being rich lowers mens' attractiveness to women

Personality and Individual Differences (Article in Press)

Too good to be ‘true’? The handicap of high socio-economic status in attractive males

Simon Chu et al.

Abstract

Empirical evidence concerning human mate-choice preferences suggests that females should select partners on the basis of cues to genetic quality and/or ability to contribute resources to childcare. Paradoxically, while high levels of both factors should be an attractive combination to females, they might also dissuade females from entering into a relationship with such males since, by definition, they are likely to be highly attractive to other females, and therefore might increase the likelihood that such a male may cheat or desert the relationship. If so, females should be wary of entering into long-term relationships with physically attractive, high status males as compared with males of lower physical attractiveness or status. We asked females to rate a number of different males in terms of attractiveness as a long-term partner. Females were presented with attractive, average and unattractive male faces paired with lonely-hearts advertisements implying high, medium or low socio-economic status. Highest ratings were consistently given to attractive males of medium status rather than high status. We suggest that females see physically attractive, high status males as being more likely to pursue a mating strategy rather than parenting strategy. Under particular circumstances, high socio-economic status in males can be subtly counter-productive in terms of attractiveness as a long-term partner.

Link

Female advantage in recognizing emotional facial expressions

Evolution and Human Behavior
Volume 27, Issue 6 , November 2006, Pages 401-416

A female advantage in the recognition of emotional facial expressions: test of an evolutionary hypothesis

Elizabeth Hampson et al.

Abstract

A set of computerized tasks was used to investigate sex differences in the speed and accuracy of emotion recognition in 62 men and women of reproductive age. Evolutionary theories have posited that female superiority in the perception of emotion might arise from women's near-universal responsibility for child-rearing. Two variants of the child-rearing hypothesis predict either across-the-board female superiority in the discrimination of emotional expressions (“attachment promotion” hypothesis) or a female superiority that is restricted to expressions of negative emotion (“fitness threat” hypothesis). Therefore, we sought to evaluate whether the expression of the sex difference is influenced by the valence of the emotional signal (Positive or Negative). The results showed that women were faster than men at recognizing both positive and negative emotions from facial cues, supporting the attachment promotion hypothesis. Support for the fitness threat hypothesis also was found, in that the sex difference was accentuated for negative emotions. There was no evidence that the female superiority was learned through previous childcare experience or that it was derived from a sex difference in simple perceptual speed. The results suggest that evolved mechanisms, not domain-general learning, underlie the sex difference in recognition of facial emotions.

Link

The Perfect comedy face

Anthony Little has created a facial composite of comedians. From the BBC:

Scientists have used computer software to come up with what they say is the perfect comedy face.

The University of Stirling team blended together 179 different facial aspects of 20 top comedians.

They said soft and feminine features, typified by Ricky Gervais, were more likely to make people laugh.

The researchers also concluded that Conservative leader David Cameron, unlike Tony Blair or Gordon Brown, has features prone to make people laugh.

However, they said it was questionable whether a funny face was an electoral asset.

Researcher Dr Anthony Little, a psychologist, whose work was commissioned by Jongleurs comedy clubs, showed faces with a range of different features to volunteers, and asked them to rate how funny they thought the person was.

He said: "The features most likely to mark male comedians out for success are predominantly soft and feminine.

"The face is a strong indication of character, and today's study appears to explain why comedians of a certain appearance would have been drawn to their career.

"The characteristics of a feminine face imply that the person may be agreeable and co-operative, which can be causal in our first impressions of comedians as being friendly and funny."

Dr Little said Mr Cameron's round and wide facial shape, large eyes and soft features meant he had the right natural physical attributes for comedy.

Actual vs. Observable Criminality

Inspired from this Telegraph story:

Race watchdogs are to investigate the national DNA database over revelations that up to three quarters of young black men will soon have their profiles stored.

Trevor Phillips, the chairman of the Commission for Racial Equality (CRE), vowed to examine whether the database breached race relations laws following the findings by The Sunday Telegraph. "This is tantamount to criminalising a generation of young black men," he said.

An estimated 135,000 black males aged 15 to 34 will be entered in the crime-fighting- database by April, equivalent to as many as 77 per cent of the young black male population in England and Wales. By contrast, only 22 per cent of young white males, and six per cent of the general population, will be on the database.

We should remember that a group's observed criminality is a function of their propensity for criminality as well as the authorities' propensity to investigate members of the group. I suspect that differences in average criminality (perhaps related to personality differences between groups) result in a (correct) perception that an individual of group A has a higher probability of engaging in some type of criminal activity than an individual of group B. This perception then leads one to investigate more thoroughly persons of group A, thus leading to a greater observable criminality for group A.

Suppose that 60% of car thefts in a city are done by Blues. The police is then justified in thinking of Blues as more likely to steal cars than Greens. If a car theft takes place, and given two suspects, a Blue and a Green, and given a limited number of police resources, the smarter choice is to investigate the Blue individual.

Suppose that the police has enough resources to investigate 1 suspect 50% of the time, and both suspects 50% of the time. Then, 50% of the time they would investigate both suspects and catch the perpetrator (30% Blues and 20% Greens), but 50% of the time they will only investigate the Blue one leading to an arrest of a Blue one in 30% of the cases.

Thus, in total there will be 60% Blues and 20% Greens that were arrested, i.e., a difference in actual criminality of 1.5x was transformed into a 3x observed one. Moreover, 80% of the total criminals would be arrested with a race-conscious policy.

Suppose now that a race-blind policy is enacted. Now, for the 50% of the time where they can only investigate 1 suspect, they pick his race randomly and with equal probability. Now they will expect to catch a Blue criminal whenever a Blue committed the crime and they happened to investigate the Blue suspect (15%) and similarly a Green one (10%). So, with a race-blind policy 75% of the total criminals would be arrested.

This illustrates the problem: using the information encoded in the "race" variable leads to more efficient crime fighting: more criminals are caught. However, it also leads to a upwardly biased estimate of the criminality of the more criminal group.

In my opinion, society should not throw away information encoded in sex, race, ethnicity, etc. in fighting crime. That is the rational choice to maximize justice. However, it should also be aware that this rational group-conscious policy biases our perception.

PS: The relevant statistics for particular human group differences, including those cited by the Telegraph, are not important for the argument presented above. I am agnostic about both the magnitude in actual criminality between different groups (e.g., men vs. women, Muslims vs. Buddhists, blacks vs. Mongoloids, etc.) as well as the potential racial biases (above and beyond the rational group-conscious choice), or racial political correctness that may further inflate/deflate observable differences.

Stability of personality from elementary school to midlife

J Pers Soc Psychol. 2006 Oct;91(4):763-79.

A first large cohort study of personality trait stability over the 40 years between elementary school and midlife.

Hampson SE, Goldberg LR.

This report provides some initial findings from an investigation of the relations between childhood Big Five personality traits assessed by elementary school teachers and similar traits assessed 40 years later by self-reports at midlife (N = 799). Short-term (1-3 years) test-retest reliabilities were lower (.22-.53) in childhood when personality was developing than they were in adulthood (.70-.79) when personality stability should be at its peak. Stability coefficients across the 40-year interval between the childhood assessment and the 2 measures of adulthood personality were higher for Extraversion (e.g., .29) and Conscientiousness (e.g., .25) than for Openness (e.g., .16), Agreeableness (e.g., .08), and Neuroticism (e.g., .00). Construct continuity between childhood and adulthood was evaluated by canonical analysis and by structural equation modeling and indicated continuity at both a broad, two-dimensional level and at the level of the Big Five. The findings are discussed in relation to A. Caspi, B. W. Roberts, and R. L. Shiner's (2005) principles of rank-order personality stability.

Link

Spiritual but not Religious

J Pers. 2006 Oct;74(5):1257-92

Spiritual but not religious? Evidence for two independent dispositions

Saucier G, Skrzypińska K

Some psychologists treat religious/spiritual beliefs as a unitary aspect of individual differences. But a distinction between mysticism and orthodox religion has been recognized by scholars as well as laypersons, and empirical studies of "ism" variables and of "spirituality" measures have yielded factors reflecting this distinction. Using a large sample of American adults, analyses demonstrate that subjective spirituality and tradition-oriented religiousness are empirically highly independent and have distinctly different correlates in the personality domain, suggesting that individuals with different dispositions tend toward different styles of religious/spiritual beliefs. These dimensions have low correlations with the lexical Big Five but high correlations with scales (e.g., Absorption, Traditionalism) on some omnibus personality inventories, indicating their relevance for studies of personality.

Link

Why we need more anthropometry

Kerim of Savage Minds, an anthropological blog, writes a post titled Anthropometry: Alive and Kicking. In it, he dismisses the 1988 All India Anthropometric Survey, North Zone : Basic Anthropometric Data, although it is not at all clear why he objects to anthropometry. I guess, anthropometry is what those bad old colonial racists did, so dismissing it requires no justification.

Anthropometry is the measurement of the human body: its shape, size, color; the collection of quantitative data about human beings. Anthropology is the study of mankind. Without anthropometric data there is no anthropology, or at most there is something like modern social or cultural "anthropology", a data-lite, theory-heavy field which generates papers with titles like "Coetzee, Agamben, and the Passion of Abu Ghraib", "The End of the Soul: Scientific Modernity, Atheism, and Anthropology in France", "Piro Designs: Painting as Meaningful Action in an Amazonian Lived World", "Agency, Personhood and the 'I' of Discourse in the Pacific and Beyond"

It is often erroneously claimed that modern science has superseded traditional physical anthropology. The old typologists, it is said, were misguided, their conclusions wrong, their caliper-wielding methods naive, or even dangerous, leading to racism, intolerance, genocide, and assorted very bad things.

On the contrary, many of the conclusions of traditional physical anthropology, such as the taxonomic division of Homo sapiens into at least four subspecies have stood the test of time, having been amply confirmed by genetic studies, as well as the multivariate analysis of craniometric and anthropometric data.

The old physical anthropology was simply limited by its lack of computational power and statistical methodology. Most of it was done before the pioneering work of R. A. Fisher's discriminant functions, before the use of classification trees, clustering algorithms, or Principal Components Analysis. Without computers, multivariate analyses of large samples were unthinkable. Anthropologists relied on their expertise, and on simple comparisons of means and standard deviations of single traits. Nonetheless, at least for the major problems, their conclusions were essentially correct.

Nowadays, computational power is abundant, statistical methodology is well established, and tools for collecting data about human personality, intelligence, genes, and appearance are there for anyone to use. Unfortunately, though, no one is using them. The Human Genome Diversity Program was shot down, and the Genographic Project, privately funded, is a much toned down version, which aims only to reconstruct human origins.

As a practical matter, anthropologists could easily do a comprehensive study of human variation. Imagine a study where 100,000 people from around the world are given a thorough anthropometric measurement, an IQ test, a personality test, a number of medical tests, and a comprehensive genetic test which can be refined down the road as gene sequencing becomes cheaper. Imagine thousands of attributes, phenotypic or genotypic, for each one of the 100,000, the first large sampling of human variation in all its measurable aspects. Such a database wouldn't cost much, but would allow us to really speak authoritatively about human variation.

What is stopping us from doing such a study? Bizarre notions about the rights of indigenous groups, a dogmatic rejection of any correlation between physical (especially racial) traits with morality, personality, or cognitive function, a pre-occupation with medical applications and pathological variation.

We need more anthropometry, not less. More psychometry too, more genetic testing, more data of every kind. Above all, more willingness to study man quantitatively, rather than a reliance on politically-correct preconceptions about ourselves.

What 2006 has brought so far

Let's see how my New Year's predictions are holding up, since the year is winding down. I have to say, I'm disappointed with the Genographic project so far; not only did they not publish a research paper yet, but it seems that their National Geographic articles have dried up as well.

• The first study on ancient Mycenaean and Minoan mtDNA.
• A study on haplogroup E-M78 subdivisions.
• A study on Minoan civilization origins.
• Successful extraction of autosomal DNA from prehistoric humans.
• Correlation of recently selected genes with IQ and/or personality.
• Even more debate between demists and acculturationists regarding the spread of the Neolithic.
  
• Even more debate between assimilationists and non-assimilationists about the Neandertals.
  
• At least one paper from the Genographic project in a venue other than National Geographic about some obscure people that no one has heard about but everyone will talk about for days. The paper will have a feel-good message about the unity of mankind.
  
• The French will continue to remain a genetic mystery, but there will be at least three more studies on Jewish population genetics.

Heritability of physical and psychological traits in 6,148 Sardinians

A new study in PLoS Genetics has estimated heritabilities of various traits over a large population of Sardinians. Please note that heritabilities calculated in one population should not be extended to other populations. If, e.g., there is a lot of environmental variation in nutrition in a population, then stature will be least affected by hereditary factors. Conversely, if all individuals are fed well, then the largest part of individual differences will be attributed to hereditary factors.

PLoS Genetics (Early Online Release)

Heritability of Cardiovascular and Personality Traits in 6,148 Sardinians

Giuseppe Pilia et al.

PROVISIONAL ABSTRACT

In large samples, phenotypic similarities between relatives yield information on the overall contribution of genes to trait variation. Large samples are especially important to compare heritability between subgroups such as young and old, or males and females. We recruited a cohort of 6,148 participants, aged 14-102, from 4 clustered towns in Sardinia. The cohort includes 34,469 relative pairs. To extract genetic information, we implemented software for variance components heritability analysis, designed to handle large pedigrees, analyze multiple traits simultaneously and model heterogeneity. Here, we report heritability analyses for 98 quantitative traits, focusing on facets of personality and cardiovascular function. We also summarize results of bivariate analyses for all pairs of traits and of heterogeneity analyses for each trait. We found a significant genetic component for every trait. On average genetic effects explained 40% of the variance for 38 blood tests, 51% for 5 anthropometric measures, 25% for 20 measures of cardiovascular function, and 19% for 35 personality traits. Four traits showed significant evidence for an X-linked component. Bivariate analyses suggested overlapping genetic determinants for many traits, including multiple personality facets and several traits related to the metabolic syndrome; but we found no evidence for shared genetic determinant that might underlie the reported association of some personality traits and cardiovascular risk factors. Models allowing for heterogeneity suggested that, in this cohort, the genetic variance was typically larger in females and in younger individuals, but interesting exceptions were observed. For example, narrow heritability of blood pressure was ~26% in individuals >42 years old, but only ~8% in younger individuals. Despite the heterogeneity in effect sizes, the same loci appear to contribute to variance in young and old and in males and females. In summary, we find significant evidence for heritability of many medically important traits, including cardiovascular function and personality. Evidence for heterogeneity by age and sex suggest that models allowing for these differences will be important in mapping quantitative traits.

Link

Femininity/Masculinity predicts male but not female homosexuality

A new article illustrates that masculinity-feminity of adolescents predicts sexual orientation in adulthood for males, but not for females. In other words, effeminate adolescents tend to grow up to be gay but this is not the case for more masculine women.

This illustrates that male and female homosexuality are different phenomena, something which is also apparent by (a) the greater prevalence of male compared to female homosexuality, and (b) the much more obvious behavioral cues of male compared to female homosexuals.

As I wrote in the old Dodona forum in 2004, distinguishing between male and female homosexuality:

Some boys are naturally effeminate or girly and are more prone to develop an abnormal sexuality during their childhood. Homosexuality is a mental illness but one which is difficult to treat because it starts early on and becomes a part of a person's core personality by the time he becomes an adult. While most men learn to act like men as part of the growin up process, homosexuals must unlearn their whole development and relearn a sexual role, something which is virtually impossible.

For lesbians, the cause is probably ugliness or fear of men. While male homosexuals often have a 'normal' appearance, lesbians tend to be unattractive -- except in porn movies of course.

Journal of Biosocial Science (forthcoming)

MASCULINITY–FEMININITY PREDICTS SEXUAL ORIENTATION IN MEN BUT NOT IN WOMEN

J. RICHARD UDRY a1 and KIM CHANTALA

Abstract

Using the nationally representative sample of about 15,000 Add Health respondents in Wave III, the hypothesis is tested that masculinity–femininity in adolescence is correlated with sexual orientation 5 years later and 6 years later: that is, that for adolescent males in 1995 and again in 1996, more feminine males have a higher probability of self-identifying as homosexuals in 2001–02. It is predicted that for adolescent females in 1995 and 1996, more masculine females have a higher probability of self-identifying as homosexuals in 2001–02. Masculinity–femininity is measured by the classical method used by Terman & Miles. For both time periods, the hypothesis was strongly confirmed for males: the more feminine males had several times the probability of being attracted to same-sex partners, several times the probability of having same-sex partners, and several times the probability of self-identifying as homosexuals, compared with more masculine males. For females, no relationship was found at either time period between masculinity and sex of preference. The biological mechanism underlying homosexuality may be different for males and females.

Link

Migration and evolution

Steve Sailer writes:

One promising possibility is the old chestnut question about why the personalities of today's Scandinavians don't seem all that much like their Viking ancestors. It's possible that the aggressive Viking personality was a winning hand in Darwinian terms back in the Dark Ages when other Europeans didn't have adequate defenses against Viking predations. But by the Middle Ages, Europeans had evolved the security system called feudalism and the Vikings were forced to stay home. The most aggressive then tended to slaughter each other in the kind of honor feuds described in Icelandic sagas, while the milder sorts kept their heads down, survived, and multiplied. (On the other hand, I'm rather skeptical of the notion that one group is more or less violent than another group, since humans seem to have a lot of capacity for violence. A nonviolent group probably wouldn't have survived. The obvious differences are in tendencies toward organized and disorganized violence.)

I was planning to compose a longer entry on the importance of migration in human evolution, but I don't think I will have the time to finish it (with all the morphing that I've been doing lately :) ) But, here is the gist of the idea:

Often, when we think of evolution, we think of it as being driven by differences in genetic fitness of different phenotypes, which correspond to differences in genetic fitness of individual "selfish" genes. Thus, we think of evolution if one phenotype or gene is more successful than another, and hence produces more of its copies in the next generation.

However, evolution can still occur even if all phenotypes and genes are equally successful in reproducing themselves. This is due to the fact that human populations are geographically and socially structured.

If in a given environment E, phenotype A is superior to phenotype B, then we would expect (over time) to see more of phenotype A and less of phenotype B. That is the essence of selection.

But, in the words of Epicurus "necessity is evil, but there is no reason to live under necessity".

In other words, humans -being the adaptible creatures that we are- often don't stick around in adverse environment E. Rather, quite often, the members of the disadvantaged phenotype B will find a new niche for themselves, either a new social niche, or -by migration- a new geographical one.

This type of population partition is -I believe- an important feature of human evolution, because of our enormous capacity to foresee the future and plan ahead.

Let's take Sailer's Vikings who inspired this blog entry. The Vikings stand at the middle of a long history of migrations of Germanic peoples out of northern Europe. Importantly, the people who left northern Europe (e.g., the Visigoths , the Varangians, the Vandals, etc.) represented the more active and warlike elements in the local population. They were the ones who when faced with poverty, climatic change, or population overflow, decided to find a new home by migration, war, and conquest. Consequently, modern Scandinavians are descended from the leftovers of those great movements. So, it should not come as a surprise that they are so passive, peace-loving and unlike the medieval Scandinavians who terrorized Europe.

Even earlier events in human evolution can be explained by looking at migration processes. For example, Polynesians and Ethiopians are both descended from the same African ancestors of the Upper Paleolithic. But, whereas the Ethiopians stayed close to the human cradle, the Polynesians are descended from the people who moved across Eurasia in a few thousand years and then made an almost crazy journey of colonization with primitive boats across the vast expanses of the Pacific Ocean. So, we should be willing to concede that some of the differences between the two peoples are due not only to long separate evolution, but also to the different kinds of people that would end up in the middle of the Pacific vs. the ones who would remain in the Horn of Africa.

The recent Americans are of course another classical example of the same process. European Americans differ from Europeans because they evolved (biologically and culturally) separately from their European ancestors, but they are also different because they are descended from a particular kind of European, who, being uncomfortable at home, decided to make a fresh start in the New World.

The destinations of migration processes tend to accumulate two kinds of individuals:

The adventurer type is the one who perceives opportunity and seizes it. The early Neolithic colonization, or the early American colonization is probably attributed to adventurer types.

The outcast type is the one who is uncompetitive and seeks a new homeland where competition is less fierce. The later American colonization, and probably the colonization of the ecologically extreme regions of the world was (is?) effected chiefly by outcast types.

(More later...)

Dancers vs. Non-Dancers: Genes and Personality

Are dancers genetically different than the rest of us? Yes, says Hebrew University researcher

What makes dancers different than the rest of us? Genetic variants, says a researcher at the Hebrew University of Jerusalem.

In a study published in the American journal, Public Library of Science Genetics, Psychology Prof. Richard P. Ebstein and his research associates have shown, through DNA examination, that dancers show consistent differences in two key genes from the general population. Ebstein is the head of the Hebrew University Psychology Department's Scheinfeld Center for Human Genetics in the Social Sciences.

This finding is not surprising, says Ebstein, in view of other studies of musicians and athletes, which also have shown genetic differences.

Ebstein and his colleagues found in an examination of 85 dancers and advanced dancing students in Israel variants of two genes that provide the code for the serotonin transporter and arginine vasopressin receptor 1a.

Both genes are involved in the transmission of information between nerve cells. The serotonin transporter regulates the level of serotonin, a brain transmitter that contributes to spiritual experience, among many other behavioral traits. The vasopressin receptor has been shown in many animal studies to modulate social communication and affiliative bonding behaviors. Both are elements involved in the age-old human social expression of dancing.

The genetic evidence was corroborated by two questionnaires distributed by the researchers to the dancers. One is the Tellegen Absorption Scale (TAS), that correlates aspects of spirituality and altered states of consciousness, and the other is the Tridimensional Personality Questionnaire (TPQ), a measure of the need for social contact and openness to communication.

The genetic and questionnaire results of the dancers were compared with those of two other groups examined – athletes as well as those who were both non-dancers and non-athletes. (Athletes were chosen for comparison since they require a good deal of physical stamina like dancers.)

When the results were combined and analyzed, it was clearly shown that the dancers exhibited particular genetic and personality characteristics that were not found in the other two groups.

The dancer "type," says Ebstein, clearly demonstrates qualities that are not necessarily lacking but are not expressed as strongly in other people: a heightened sense of communication, often of a symbolic and ceremonial nature, and a strong spiritual personality trait.

Others involved in the research with Ebstein were his Ph.D. student Rachel Bachner- Melman, as well as additional researchers from Israel and France.

PLoS Genetics Volume 1 Issue 3 SEPTEMBER 2005

AVPR1a and SLC6A4 Gene Polymorphisms Are Associated with Creative Dance Performance
Rachel Bachner-Melman et al.

Dancing, which is integrally related to music, likely has its origins close to the birth of Homo sapiens, and throughout our history, dancing has been universally practiced in all societies. We hypothesized that there are differences among individuals in aptitude, propensity, and need for dancing that may partially be based on differences in common genetic polymorphisms. Identifying such differences may lead to an understanding of the neurobiological basis of one of mankind's most universal and appealing behavioral traits—dancing. In the current study, 85 current performing dancers and their parents were genotyped for the serotonin transporter (SLC6A4: promoter region HTTLPR and intron 2 VNTR) and the arginine vasopressin receptor 1a (AVPR1a: promoter microsatellites RS1 and RS3). We also genotyped 91 competitive athletes and a group of nondancers/nonathletes (n = 872 subjects from 414 families). Dancers scored higher on the Tellegen Absorption Scale, a questionnaire that correlates positively with spirituality and altered states of consciousness, as well as the Reward Dependence factor in Cloninger's Tridimensional Personality Questionnaire, a measure of need for social contact and openness to communication. Highly significant differences in AVPR1a haplotype frequencies (RS1 and RS3), especially when conditional on both SLC6A4 polymorphisms (HTTLPR and VNTR), were observed between dancers and athletes using the UNPHASED program package (Cocaphase: likelihood ratio test [LRS] = 89.23, p = 0.000044). Similar results were obtained when dancers were compared to nondancers/nonathletes (Cocaphase: LRS = 92.76, p = 0.000024). These results were confirmed using a robust family-based test (Tdtphase: LRS = 46.64, p = 0.010). Association was also observed between Tellegen Absorption Scale scores and AVPR1a (Qtdtphase: global chi-square = 26.53, p = 0.047), SLC6A4 haplotypes (Qtdtphase: chi-square = 2.363, p = 0.018), and AVPR1a conditional on SCL6A4 (Tdtphase: LRS = 250.44, p = 0.011). Similarly, significant association was observed between Tridimensional Personality Questionnaire Reward Dependence scores and AVPR1a RS1 (chi-square = 20.16, p = 0.01). Two-locus analysis (RS1 and RS3 conditional on HTTLPR and VNTR) was highly significant (LRS = 162.95, p = 0.001). Promoter repeat regions in the AVPR1a gene have been robustly demonstrated to play a role in molding a range of social behaviors in many vertebrates and, more recently, in humans. Additionally, serotonergic neurotransmission in some human studies appears to mediate human religious and spiritual experiences. We therefore hypothesize that the association between AVPR1a and SLC6A4 reflects the social communication, courtship, and spiritual facets of the dancing phenotype rather than other aspects of this complex phenotype, such as sensorimotor integration.

Link