Russian anthropology textbook

A recent anthropological textbook: АНТРОПОЛОГИЯ (link)

Use Babelfish to translate.

The shape of things to come in autosomal DNA analysis

In the recent African American Lives documentary, geneticists were able to estimate the most probable African origin of Henry Louis Gates, Jr. by using a 11,555-SNP array. The following paper reports on the study of several human populations using this array.

Until now, it was well known that major continental origin could be predicted accurately, but by increasing the number of polymorphisms used, one can go one step further and discover patterns at the intra-continental level.

The following plot of the first PCA components is pretty self-explanatory. As you can see, very clear clusters corresponding to populations emerge when such large numbers of polymorphisms are used.



Human Genomics Volume 2, Number 2, June 2005

Large-scale SNP analysis reveals clustered and continuous patterns of human genetic variation

Shriver, Mark D et al.

Abstract:
Understanding the distribution of human genetic variation is an important foundation for research into the genetics of common diseases. Some of the alleles that modify common disease risk are themselves likely to be common and, thus, amenable to identification using gene-association methods. A problem with this approach is that the large sample sizes required for sufficient statistical power to detect alleles with moderate effect make gene-association studies susceptible to false-positive findings as the result of population stratification.1,2 Such type I errors can be eliminated by using either family-based association tests or methods that sufficiently adjust for population stratification.3–5 These methods require the availability of genetic markers that can detect and, thus, control for sources of genetic stratification among populations. In an effort to investigate population stratification and identify appropriate marker panels, we have analysed 11,555 single nucleotide polymorphisms in 203 individuals from 12 diverse human populations. Individuals in each population cluster to the exclusion of individuals from other populations using two clustering methods. Higher-order branching and clustering of the populations are consistent with the geographic origins of populations and with previously published genetic analyses. These data provide a valuable resource for the definition of marker panels to detect and control for population stratification in population-based gene identification studies. Using three US resident populations (European-American, African-American and Puerto Rican), we demonstrate how such studies can proceed, quantifying proportional ancestry levels and detecting significant admixture structure in each of these populations.

Link

Behavioral Inhibition and Blond Hair

Via Gene Expression.

Biological Psychology (Article in Press)

Association of behavioral inhibition with hair pigmentation in a European sample

Eva Moehler et al.

Abstract

Behavioral inhibition, a temperamental trait signalling a predisposition to childhood and adolescent anxiety disorders, is slightly more frequent in America among Caucasian children having blue irises. This paper examines a community sample of 101 German toddlers assessed for behavioral inhibition in a standardized laboratory procedure. Hair pigmentation was found to be significantly associated with behavioral inhibition in the sense that blond children exhibited higher fear scores. As in American samples, blue-eyed children had a higher fear score than did other children, but this difference was not statistically significant.

Link

Ethnicity-specific disease risk in African Americans

This paper shows how a particular gene variant was introduced to the African American population by admixture with Europeans and how African Americans are at a higher risk of heart disease because of it.

This illustrates how a gene that has originated in one population can lead to problems when it is found in a different genetic-environmental context.

Nature Genetics 38, 68 - 74 (2006)
Published online: 10 November 2005; | doi:10.1038/ng1692

A variant of the gene encoding leukotriene A4 hydrolase confers ethnicity-specific risk of myocardial infarction

Anna Helgadottir et al.

Variants of the gene ALOX5AP (also known as FLAP) encoding arachidonate 5-lipoxygenase activating protein are known to be associated with risk of myocardial infarction1. Here we show that a haplotype (HapK) spanning the LTA4H gene encoding leukotriene A4 hydrolase, a protein in the same biochemical pathway as ALOX5AP, confers modest risk of myocardial infarction in an Icelandic cohort. Measurements of leukotriene B4 (LTB4) production suggest that this risk is mediated through upregulation of the leukotriene pathway. Three cohorts from the United States also show that HapK confers a modest relative risk (1.16) in European Americans, but it confers a threefold larger risk in African Americans. About 27% of the European American controls carried at least one copy of HapK, as compared with only 6% of African American controls. Our analyses indicate that HapK is very rare in Africa and that its occurrence in African Americans is due to European admixture. Interactions with other genetic or environmental risk factors that are more common in African Americans are likely to account for the greater relative risk conferred by HapK in this group.

Link

More African American Lives

I watched African American Lives, finding it to be quite well done, and informative. I took some notes on some of the celebrities which were shown in the program.

Henry Louis Jr, 50%-50% European/Sub-Saharan African



Oprah Winfrey 89%-8%-3% Sub-Saharan African/Native American/East Asian



Quincy Jones 63%/34% Sub-Saharan African/European



Sarah Lawrence Lightfoot 45% European



Chris Tucker 83%/10% Sub-Saharan African/Native American (?)



Mae Jemison 13% East Asian



Whoopi Goldberg 90% Sub-Saharan African



Additionally, Mark Shriver was shown to take a 3D scan of Henry Louis, Jr's head, and it was said that he was working on correlating facial features with genetic admixture. On the minus side, the 13% "East Asian" component in Mae Jamison was explained by "Chinese laborers", rather than the more probable explanation of a difficulty in distinguishing between Native Americans and East Asians.

See also Mozart's Skull and the DNA of the famous

The sex of attractive faces is identified more easily

Perception. 2005;34(12):1459-74.

The role of facial attractiveness and facial masculinity/femininity in sex classification of faces.

Hoss RA, Ramsey JL, Griffin AM, Langlois JH.

We tested whether adults (experiment 1) and 4 - 5-year-old children (experiment 2) identify the sex of highly attractive faces faster and more accurately than not very attractive faces in a reaction-time task. We also assessed whether facial masculinity/femininity facilitated identification of sex. Results showed that attractiveness facilitated adults' sex classification of both female and male faces and children's sex classification of female, but not male, faces. Moreover, attractiveness affected the speed and accuracy of sex classification independently of masculinity/femininity. High masculinity in male faces, but not high femininity in female faces, also facilitated sex classification for both adults and children. These findings provide important new data on how the facial cues of attractiveness and masculinity/femininity contribute to the task of sex classification and provide evidence for developmental differences in how adults and children use these cues. Additionally, these findings provide support for Langlois and Roggman's (1990 Psychological Science 1 115 121) averageness theory of attractiveness.

Link

Genetic influences on life span kick in after age 60

Human Genetics (Online first)

Genetic influence on human lifespan and longevity

Jacob vB. Hjelmborg et al.

Abstract There is an intense search for longevity genes in both animal models and humans. Human family studies have indicated that a modest amount of the overall variation in adult lifespan (approximately 20–30%) is accounted for by genetic factors. But it is not known if genetic factors become increasingly important for survival at the oldest ages. We study the genetic influence on human lifespan and how it varies with age using the almost extinct cohorts of Danish, Finnish and Swedish twins born between 1870 and 1910 comprising 20,502 individuals followed until 2003–2004. We first estimate mean lifespan of twins by lifespan of co-twin and then turn to the relative recurrence risk of surviving to a given age. Mean lifespan for male monozygotic (MZ) twins increases 0.39 [95% CI (0.28, 0.50)] years for every year his co-twin survives past age 60 years. This rate is significantly greater than the rate of 0.21 (0.11, 0.30) for dizygotic (DZ) males. Females and males have similar rates and these are negligible before age 60 for both MZ and DZ pairs. We moreover find that having a co-twin surviving to old ages substantially and significantly increases the chance of reaching the same old age and this chance is higher for MZ than for DZ twins. The relative recurrence risk of reaching age 92 is 4.8 (2.2, 7.5) for MZ males, which is significantly greater than the 1.8 (0.10, 3.4) for DZ males. The patterns for females and males are very similar, but with a shift of the female pattern with age that corresponds to the better female survival. Similar results arise when considering only those Nordic twins that survived past 75 years of age. The present large population based study shows genetic influence on human lifespan. While the estimated overall strength of genetic influence is compatible with previous studies, we find that genetic influences on lifespan are minimal prior to age 60 but increase thereafter. These findings provide a support for the search for genes affecting longevity in humans, especially at advanced ages.

Link

What is your voice pitch?

Continuing the previous post, finally you have a way of figuring out what your voice pitch is, and to see how you measure up compared with other males.

According to the above cited article, the testees' recordings had:

mean length=17.9 s, mean F0=113.2 Hz, F0 range=85.6-154.6 Hz

F0 is a correlate of pitch and is the parameter that you must estimate.

According to the authors, testees had to read an excerpt from the Rainbow Passage:

When the sunlight strikes raindrops in the air, they act as a prism and form a rainbow. The rainbow is a division of white light into many beautiful colors. These take the shape of a long round arch, with its path high above, and its two ends apparently beyond the horizon. There is , according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond his reach, his friends say he is looking for the pot of gold at the end of the rainbow. Throughout the centuries people have explained the rainbow in various ways. Some have accepted it as a miracle without physical explanation. To the Hebrews it was a token that there would be no more universal floods. The Greeks used to imagine that it was a sign from the gods to foretell war or heavy rain. The Norsemen considered the rainbow as a bridge over which the gods passed from earth to their home in the sky. Others have tried to explain the phenomenon physically. Aristotle thought that the rainbow was caused by reflection of the sun's rays by the rain. Since then physicists have found that it is not reflection, but refraction by the raindrops which causes the rainbows. Many complicated ideas about the rainbow have been formed. The difference in the rainbow depends considerably upon the size of the drops, and the width of the colored band increases as the size of the drops increases. The actual primary rainbow observed is said to be the effect of super-imposition of a number of bows. If the red of the second bow falls upon the green of the first, the result is to give a bow with an abnormally wide yellow band, since red and green light when mixed form yellow. This is a very common type of bow, one showing mainly red and yellow, with little or no green or blue.

I have no idea which excerpt they used, so I said the whole thing, which took me around 90 seconds, as opposed to the 17.9 average recording length in their experiments.

Ok, so how do you do it?

First download the Praat software which is available for different platforms and then run it.

Then do "New->Record Mono Sound" and speak the passage into your microphone. Then do "Save to list".

Now, select the recording and click edit. In the new window that will appear, go to Pitch->Pitch Settings and set pitch range from 75 to 300Hz.

Then, select the part of your recording that you contains your speech by clicking at the beginning and dragging the mouse to the end.

Then View->Show Analyses and make the "Longest Analysis" as long as your recording.

Finally, Pitch->Get Pitch, and there you have it!

My own pitch is 119Hz over the entire passage. I did notice that as I was speaking and getting more impatient my voice started to rise in tone. I then calculated the pitch in the first half of the recording (117Hz) vs. the second half (121Hz) and indeed it seemed that this was the case. In the first 17.9 seconds of the recording, which corresponds to the mean length of the authors' recordings, my pitch was 116Hz.

Leave comment or trackback if you manage to get through the process; it's easier than might seem from the above description.

Update

David Puts, first author of this study writes in the comments:

In response, to Jason Malloy's question, the male participants were racially mixed--mostly white, but maybe 10 (out of 111) black. I didn't find a significant difference in F0 between ethnicities.

Regarding Gaius' question, yes, Dabbs and Mallinger (1999) (cited in the paper) found a significant correlation between circulating testosterone levels and F0 in males of this age group. And Need et al. (1993) (also cited in our paper) found that testosterone treatment lowers voice pitch.

Finally, I think we sound kind of whiny on voicemail recordings, etc. because the microphones on these devices are not the best quality and don't pick up the entire sound spectrum very well.

Thanks for your interest!

More positive selection in recent humans: CASP12

It seems that positive selection studies are coming out in droves; you can use the search function ("positive selection") to find a bunch of them reported on this blog.

The newest study appears as a preprint in the American Journal of Human Genetics and is about a gene called human caspase-12 (CASP12) which has two variants: the active one is the original form, but the inactive one seems to have undergone positive selection beginning 60-100ky ago.

It is suggested that the inactive form confers some advantage against sepsis, which was also implicated in a frequent mtDNA haplogroup recently.

The distribution of the two versions of the gene...



... shows that the active version is largely confined to Sub-Saharan Africa. This parallels the situation in Microcephalin and ASPM.

The highest frequencies of the active version are in the Mbuti (0.60) and the San (0.57). These populations have a high frequency of non-M168 related Y-chromosomes and non-L3 related mtDNA and are thus descended from the most ancient African populations (which I have called "Paleoafricans"), rather than the more recent emergence of an population in east Africa ("Afrasians") which spawned the Eurasians and assimilated most Paleoafricans during its spread within Africa. In this regard, it is interesting that an east African population from Kenya shows the minimum (0.04) frequency of the active gene of CASP12.

American Journal of Human Genetics (in press)

Spread of an inactive form of caspase-12 in humans due to recent
positive selection

Yali Xue et al.

Abstract

The human caspase-12 gene is polymorphic for the presence or absence of a stop codon, resulting in the occurrence of both active (ancestral) and inactive (derived) forms of the gene in the population. It has previously been shown that carriers of the inactive gene are more resistant to severe sepsis. We have now investigated whether the inactive form has spread because of neutral drift or positive selection. We determined its distribution in a worldwide sample of 52 populations and re-sequenced the gene in 77 individuals from the HapMap Yoruba, Han Chinese and European populations. There is strong evidence for positive selection from low diversity, skewed allele frequency spectra and the predominance of a single haplotype. We suggest that the inactive form of the gene arose in Africa ~100-500 thousand years ago (KYA) and was initially neutral or almost neutral, but that positive selection beginning ~60-100 KYA drove it to near-fixation. We further propose that its selective advantage was sepsis resistance in populations that experienced more infectious diseases as population sizes and densities increased.

Link (pdf)

Alan Templeton vs. Out of Africa with replacement: 1-0

Alan Templeton has followed up his work in Out of Africa again and again where he argued that the human genome holds evidence that is incompatible with an exclusively recent origin of modern humans. While human mtDNA and Y-chromosomes coalesce to a time less than 200ky and are thus contemporaneous with the emergence of anatomically modern humans, we also possess genes that are far older, and are best explained by the retention of ancestry from populations other than those emerging recently in the African continent.

Templeton used classical hypothesis testing to formally reject the Out of Africa with replacement model with a staggeringly low probability. It's possible that his procedure might be contested, but I just can't see how anyone can really support the replacement theory any more.

Templeton also believes that there were several Out of Africa movements, each of them leaving a "signature" in the genomic ancestry of modern humans. Different genes are dated to each of these three movements:



Templeton also finds that the three Out of Africa movements correlate quite well with archaeologically/anthropologically established movements:

These dates overlay well upon the fossil and archaeological record, with the first expansion corresponding to the original expansion of Homo erectus out of Africa into Eurasia (Aguirre and Carbonell, 2001; Bar-Yosef and Belfer-Cohen, 2001; Anto´n et al., 2002; Vekua et al., 2002) and the development of a culture capable of keeping impaired individuals alive for many years (Lordkipanidze et al., 2005). The second expansion corresponds to the spread of Acheulean culture into much of Eurasia after an earlier African origin (Asfaw et al., 1992; Hou et al., 2000) and the initiation of a substantial increase in cranial capacity (Ruff et al., 1997; Relethford, 2001b; Rightmire, 2004). The most recent expansion out of Africa corresponds to the spread of several anatomically modern traits into Eurasia after an earlier African origin (Stringer, 2002; White et al., 2003).

This certainly also seems to agree with Erik Trinkaus' recent statement:

Versions of the assimilation model have remained contenders for the interpretation of modern human phylogenetic emergence, if frequently overshadowed by the more polarized regional continuity (with gene flow) and (out of Africa with) replacement scenarios. The last two interpretations are finally intellectually dead. Both are contradicted by available evidence, and it is time for the discussion to move on. Yet, despite the general acceptance of some form of the assimilation model, issues remain.

Update... but Milford Wolpoff writes in the comments (which disappear after 4 months on Haloscan):

I just don't see how Templeton's excellent review somehow supports Trinkaus' comment. ET asserts that multiregional evolution is "finally intellectually dead" whereas Templeton describes an interpretation of human evolution that is compatible with multiregional evolution, as he has noted. Trinkaus would replace multiregional evolution with his "assimilation theory" - an interpretation that does not seem to differ from multiregional evolution except by name, which perhaps explains the problem.

New analysis shows three human migrations out of Africa (excerpt):

Feb. 2, 2006 — A new, more robust analysis of recently derived human gene trees by Alan R. Templeton, Ph.D, of Washington University in St Louis, shows three distinct major waves of human migration out of Africa instead of just two, and statistically refutes — strongly — the 'Out of Africa' replacement theory.

That theory holds that populations of Homo sapiens left Africa 100,000 years ago and wiped out existing populations of humans. Templeton has shown that the African populations interbred with the Eurasian populations — thus, making love, not war.

"The 'Out of Africa' replacement theory has always been a big controversy," Templeton said. "I set up a null hypothesis and the program rejected that hypothesis using the new data with a probability level of 10 to the minus 17th. In science, you don't get any more conclusive than that. It says that the hypothesis of no interbreeding is so grossly incompatible with the data, that you can reject it."

Templeton's analysis is considered to be the only definitive statistical test to refute the theory, dominant in human evolution science for more than two decades.

"Not only does the new analysis reject the theory, it demolishes it," Templeton said.

Templeton published his results in the Yearbook of Physical Anthropology, 2005.

American Journal of Physical Anthropology
Volume 128, Issue S41 , Pages 33 - 59

Haplotype Trees and Modern Human Origins (p 33-59)

Alan R. Templeton

Abstract

A haplotype is a multisite haploid genotype at two or more polymorphic sites on the same chromosome in a defined DNA region. An evolutionary tree of the haplotypes can be estimated if the DNA region had little to no recombination. Haplotype trees can be used to reconstruct past human gene-flow patterns and historical events, but any single tree captures only a small portion of evolutionary history, and is subject to error. A fuller view of human evolution requires multiple DNA regions, and errors can be minimized by cross-validating inferences across loci. An analysis of 25 DNA regions reveals an out-of-Africa expansion event at 1.9 million years ago. Gene flow with isolation by distance was established between African and Eurasian populations by about 1.5 million years ago, with no detectable interruptions since. A second out-of-Africa expansion occurred about 700,000 years ago, and involved interbreeding with at least some Eurasian populations. A third out-of-Africa event occurred around 100,000 years ago, and was also characterized by interbreeding, with the hypothesis of a total Eurasian replacement strongly rejected (P < 10-17). This does not preclude the possibility that some Eurasian populations could have been replaced, and the status of Neanderthals is indecisive. Demographic inferences from haplotype trees have been inconsistent, so few definitive conclusions can be made at this time. Haplotype trees from human parasites offer additional insights into human evolution and raise the possibility of an Asian isolate of humanity, but once again not in a definitive fashion. Haplotype trees can also indicate which genes were subject to positive selection in the lineage leading to modern humans. Genetics provides many insights into human evolution, but those insights need to be integrated with fossil and archaeological data to yield a fuller picture of the origin of modern humans.

Link

IQ at age 18-20 predicts mortality 30 years later

This is probably due to the fact that IQ is a signal of good overall health, and that different occupational and social worlds are inhabited by people depending on their cognitive ability.

Int J Epidemiol. 2006 Jan 30; [Epub ahead of print]

The association between cognitive ability measured at ages 18-20 and mortality during 30 years of follow-up--a prospective observational study among Swedish males born 1949-51.

Hemmingsson T, Melin B, Allebeck P, Lundberg I.

OBJECTIVES: An association between childhood cognitive ability measured with IQ tests and mortality has been reported recently. It is not clear from those studies if the relative risk is increased only among those in the lower end of the IQ score scale or if there is graded increase in mortality from the lowest to the highest. This study aims to investigate the association between cognitive ability measured at age 18-20 and mortality during a 30 year period of follow-up. METHODS: Data on cognitive ability was collected from 49 323 men, born in 1949-51, who were conscripted for compulsory military training in 1969/70. Data on mortality were obtained from the Causes of Death register 1971-2000. RESULTS: Cognitive ability was a strong predictor of all-cause mortality, cardiovascular disease (CVD)-mortality, mortality from violent causes, and alcohol-related mortality. A striking finding was a pronounced gradient in mortality risk across all IQ score groups. Adjustment for adult socioeconomic position attenuated the increased risk somewhat [for all-cause mortality: crude hazard ratio (HR) 1.16 (1.13-1.19), adjusted HR 1.12 (1.09-1.15)]. CONCLUSION: IQ test score measured in late adolescence (only males) was a significant predictor of all-cause, as well as cause-specific (CVD and injuries), mortality during 30 years of follow-up. The risk increased from high to low IQ test score results for all outcomes.

Link

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

The pitch of male voices

Evolution and Human Behavior (Article in Press)

Dominance and the evolution of sexual dimorphism in human voice pitch

David Andrew Puts et al.

Abstract

The developmental and anatomical causes of human voice sexual dimorphisms are known, but the evolutionary causes are not. Some evidence suggests a role of intersexual selection via female mate choice, but other evidence implicates male dominance competition. In this study, we examine the relationships among voice pitch, dominance, and male mating success. Males were audio recorded while participating in an unscripted dating-game scenario. Recordings were subsequently manipulated in voice pitch using computer software and then rated by groups of males for dominance. Results indicate that (1) a masculine, low-pitch voice increases ratings of men's physical and social dominance, augmenting the former more than the latter; and (2) men who believe they are physically dominant to their competitor lower their voice pitch when addressing him, whereas men who believe they are less dominant raise it. We also found a nonsignificant trend for men who speak at a lower pitch to report more sexual partners in the past year. These results are consistent with the hypothesis that male intrasexual competition was a salient selection pressure on the voices of ancestral males and contributed to human voice sexual dimorphism.

Link

News from the DNA testing world: DNA Tribes / genebase / DNA Heritage

Competition is great, and there are some new genetics tests on the market. A company called DNA Tribes is offering the CODIS marker set plus interpretation of the results, by comparing them with "300 global populations". The 13 CODIS markers are highly polymorphic and are used in forensics for this purpose. It is not at all clear whether 13 markers (x2, since these are biparentally inherited) suffice to differentiate between different ethnic groups, especially since the CODIS set was designed for individual identification as opposed to population studies.

genebase is another company that I hadn't seen before. Their web site is quite well done. They seem to specialize in Y chromosome testing, offering 20-STR and 44-STR tests. Such tests are usually useful for genealogy purposes, and not for tracing deep ancestral origins which are determined by UEP (unique event polymorphism) tests defining unique phylogenetic clades (haplogroups).

DNA Heritage is an established company which had offered testing of Y-STRs and is now offering a $99 test which determines your fine-resolution haplogroup. If you don't care about genealogy but just want to find out your deep patrilineal ancestry then this test would be quite handy. This is perhaps what the Genographic Project should be offering, since they are supported to study your deep ancestral origins; rather, the GP only performs a 12-STR test from which your haplogroup is predicted. The GP test and the DNA Heritage test have the same price, but the fine resolution test offered by DNA Heritage will give you much clearer information about your deep ancestry, e.g., telling you that you conclusively belong to haplogroup E3b1 vs. a prediction that you belong in haplogroup E3b.

Neolithization of Mediterranean Europe

The English version of this abstract is so appalling, that I prefer to post the French original. The map of the spread of the Neolithic in the Mediterranean, reproduced from [J. Guilaine, De la vague à la tombe, La conquête néolithique de la Méditerranée, Seuil, Paris (2003)] will come in handy:



Comptes Rendus Palevol
(Article in Press)

Climat et néolithisation de l'Europe méditerranéenne

Jean-Pierre Mohen

Résumé

L'évolution du climat, pendant la période néolithique, a été sûrement cruciale pour l'avènement d'une économie de production, en relation avec le milieu naturel. Il est intéressant à ce sujet, de suivre alors, entre 10000 et 2000 BC, les changements écologiques de la partie européenne de la Méditerranée septentrionale et ceux, très différents, de la partie africaine au sud, qui connaît deux séquences désertiques aux lourdes conséquences humaines. Inversement, l'Europe méridionale néolithique développe alors une société nouvelle, rurale et marchande, avec la construction des premiers villages, l'occupation des îles liées à des commerces spécialisés (obsidienne, cuivre, poteries...), recherche d'identités sociales (grands travaux dont fortifications et mégalithes) et religieuses (déesse mère et ancêtres) entraînant parfois des conflits guerriers.

Link

African American lives

Fascinating look into history, race and DNA is a new TV program by Henry Louis Gates, Jr. investigating the genealogy of African Americans, including some well-known celebrities:

Gates explores the personal histories of his family and the families of Winfrey, comedian Chris Tucker, musician Quincy Jones, astronaut Mae Jemison, Bishop T.D. Jakes, neurosurgeon Dr. Ben Carson, actress Whoopi Goldberg and author and Harvard sociologist Sara Lawrence-Lightfoot.

Interestingly:

Only Jakes was correct when he said he was Ebo.

"I think it speaks to how accurately historical traditions are passed down through African families," Jakes said. "In the absence of our early ancestors being able to read and write, the verbal transition of information was the only applicable way to disseminate information.http://www.blogger.com/img/gl.quote.gif
insert blockquote

"My ancestors had told us that our family had come from Nigeria and we were from the tribe Ebo. But this was verbally passed down from generation to generation. And Dr. Gates confirmed it through the research."

And:

"When we did my father's admixture test, my father is 67 percent white," Gates said. "I'm 50 percent. What does that mean? Does that make me less black? I had to ask all those questions. I'm very secure in my African-American identity.

...

"It's standard for those of us who have white ancestry to have inherited that white ancestry from the male line," Gates said. "My Y chromosome goes back to Europe and my mitochondrial DNA goes back to Europe. And what that means is that I have a white female ancestor since colonial times. So that means some black man slept with some white woman between 1619 and 1750."

This is perhaps why social-cultural "race" should not be confused with the underlying biological-genomic race. While Gates is socially "African-American", biologically he is Caucasoid-Negroid with Caucasoid patrilineal and matrilineal ancestors.

Social race has to do with the cultural perceptions of race in a given society; for example, in the American society, biracial individuals such as Gates, or Halle Berry are viewed as black or African American.

Biological race has to do with the underlying genomic ancestry of individuals, which is roughly the fraction of their genome inherited from the major continental gene pools prior to their widespread geographical intermixing in modern times.

Both social and biological race are important, and the two are obviously correlated, but one should always keep in mind that they are not the same thing.