"Mormons are largely Puritans" (JayMan's latest embarrassing averral)

On twitter, someone responds to a story about Glenn Beck's banning coverage of Donald Trump from his show with "Mormons r becoming some the worst #cuckservatives-missions to Haiti & China & letting their daughters marry Samoans". JayMan seizes the opportunity to inform us: "Mormons are largely Puritans (augmented with Scandinavians)."

This is of course simply false. While Puritan ancestry is found at higher levels among Mormons than in the US population in general, it's not true that Mormons today are of predominantly Puritan descent. (Nor is any other major population in America today of predominantly Puritan descent.)

In addition to Scandinavians, converts from missionary efforts in Britain form a major component in the ancestry of those with early Mormon roots. Moreover, most of the British converts came from areas outside of East Anglia and should tend to be "clannish" relative to New England Puritans in the JayMan understanding of things.

Hail, looking at Mitt Romney's ancestry, found:

  • Most of his ancestral stock consists of early converts to Mormonism from Britain (most from Northwest-England and Scotland) who were impelled to the USA from the 1830s to the 1850s, settling directly in Mormon communities.
  • Colonial-Yankees account for 27% of Romney’s ancestral stock.
  • 12.5% (one-eighth) of his ancestral stock comes from Northern-Germany.
The current president of the Mormon church, Thomas S. Monson, has no colonial American ancestry whatsoever. He's half Scottish, 1/4 northern English, and 1/4 Swedish.

What makes this all even more amusing is that Glenn Beck was not even born a Mormon. He's a convert, and per wikipedia:

He is descended from German immigrants who came to the United States in the 19th century.[24] Beck was raised as a Roman Catholic and attended Immaculate Conception Catholic School in Mount Vernon.

Glenn and his older sister moved with their mother to Sumner, Washington, attending a Jesuit school[25] in Puyallup.

Iron Age and Anglo-Saxon genomes from East England reveal British migration history

A preprint on some ancient DNA work in England is up. Researchers sequenced samples from seven early and middle Anglo-Saxon period and three late Iron Age (presumably Celtic) skeletons.

We  generated  a  principal  component  plot  of  the  ten  ancient  samples  together with  relevant  European  populations  selected  from  published  data 10,11  (Extended data  Figure  3).  The  ancient  samples  fall  within  the  range  of  modern  English  and Scottish  samples,  with  the  Iron  Age  samples  from  Hinxton  and  Linton  falling closer  to  modern  English  and  French  samples,  while  most  Anglo-­Saxon  era samples  are  closer  to  modern  Scottish  and  Norwegian  samples.  Overall,  though, population  genetic  differences  between  these  samples  at  common  alleles  are very  slight.

While  principal  component  analysis  can  reveal  relatively  old  population structure,  such  as  generated  from  long-­‐term  isolation-­‐by-­‐distance  models 12 , whole  genome  sequences  let  us  study  rare  variants  to  gain  insight  into  more recent  population  structure. [. . .]

There are  striking  differences  in  the  sharing  patterns  of  the  samples,  illustrated  by  the ratio  of  the  number  of  rare  alleles  shared  with  Dutch  individuals  to  the  number shared  with  Spanish  individuals  (Figure  2a).   The  middle  Anglo-­‐Saxon  samples from  Hinxton  (HS1,  HS2,  HS3)  share  relatively  more  rare  variants  with  modern Dutch  than  the  Iron  Age  samples  from  Hinxton  (HI1,  HI2)  and  Linton  (L).  The early  Anglo-­‐Saxon  samples  from  Oakington  are  more  diverse,  with  O1  and  O2 being  closer  to  the  middle  Anglo-­‐Saxon  samples,  O4  exhibiting  the  same  pattern as  the  Iron  Age  samples,  and  O3  showing  an  intermediate  level  of  allele  sharing, suggesting  mixed  ancestry.  The  differences  between  the  samples  are  highest  in low  frequency  alleles  and  decrease  with  increasing  allele  frequency.  This  is consistent  with  mutations  of  lower  frequency  on  average  being  younger, reflecting  more  recent  distinct  ancestry,  compared  with  higher  frequency mutations  reflecting  older  shared  ancestry.  

Comparing the relative number of rare alleles shared with the Dutch and Spanish samples, the researchers estimate 30% Anglo-Saxon admixture in the present-day East English and 20% in the Scottish and Welsh.

We  also  examined  using  the  same  method  30  modern  samples  from  the  UK10K project   16 ,  10  each  with  birthplaces  in  East  England,  Wales  and  Scotland.  Overall, these  samples  are  closer  to  the  Iron  Age  samples  than  to  the  Anglo-­‐Saxon  era samples  (Figure  2a).  There  is  a  small  but  significant  difference  between  the  three modern  British  sample  groups,  with  East  English  samples  sharing  slightly  more alleles  with  the  Dutch,  and  Scottish  samples  looking  more  like  the  Iron  Age samples.  To  quantify  the  ancestry  fractions,  we  fit  the  modern  British  samples with  a  mixture  model  of  ancient  components,  by  placing  all  the  samples  on  a linear  axis  of  relative  Dutch  allele  sharing  that  integrates  data  from  allele  counts one  to  five  (Figure  2b).  By  this  measure  the  East  England  samples  are  consistent with  30%  Anglo-­‐Saxon  ancestry  on  average,  with  a  spread  from  20%  to  40%, and  the  Welsh  and  Scottish  samples  are  consistent  with  20%  Anglo-­‐Saxon ancestry  on  average,  again  with  a  large  spread  (Supplementary  Table  2).  An alternative  and  potentially  more  direct  approach  to  estimate  these  fractions  is  to measure  rare  allele  sharing  directly  between  the  modern  British  and  the  ancient samples.  While  being  much  noisier  than  the  analysis  using  Dutch  and  Spanish outgroups,  this  yields  consistent  results  (Extended  Data  Figure  4  and Supplementary  Table  2).  In  summary,  this  analysis  suggests  that  only  20-­‐30%  of the  ancestry  of  modern  Britons  was  contributed  by  Anglo-­‐Saxon  immigrants, with  the  higher  number  in  East  England  closer  to  the  immigrant  source.  The difference  between  the  three  modern  groups  is  surprisingly  small  compared  to the  large  differences  seen  in  the  ancient  samples,  although  we  note  that  the UK10K  sample  locations  may  not  fully  reflect  historical  geographical  population structure  because  of  recent  population  mixing.
I have not thought about it deeply, but the rare variant comparison method used by the authors seems like it should produce reasonable results, at least for the relatively straightforward admixture estimates (with the understanding that Anglo-Saxons and Iron Age Britons are not the only two possible source populations for the modern British). I will say I was surprised to see Britain sharing a branch with Finland in this plot (even though it's a short one) to the exclusion of Denmark and Netherlands:

I've seen a few people interpret this study's estimates as a vindication of the ridiculous admixture estimates featured in the People of the British Isles project paper. For me, the ancient DNA results confirm my initial impression: the methods the POBI authors used to generate their estimates of ancient admixture were useless for divining what they thought they could divine.

That this 30% estimate informed by ancient DNA falls within the range of estimates suggested by the POBI authors is primarily a testament to the extremely broad range of possible admixture estimates they offered up (spanning 10% to 50%, depending on what one subjectively deemed "likely"). The POBI authors themselves were pushing for ~10% Anglo-Saxon admixture in the 19th-century Central and South English population (and if I recall correctly ~0% in the Welsh). POBI volunteers were primarily middle-aged or older people who could document four grandparents all born in particular locations. The UK10K modern British samples appearing in the ancient DNA paper are not screened in a similar manner, but are simply classified based on the sample donor's birth place. This means at least a couple generations (and probably disproportionately important generations, at that, as concerns mobility) of additional homogenization will have taken place.

So I have little doubt POBI samples from East Anglia (proxies for 19th-century East Anglians) would produce higher estimates of Anglo-Saxon admixture than "East England" UK10K samples (though apparently at present only microarray data, and not the whole genome sequencing data that would be necessary for the rare variant comparisons, is available for POBI samples). Levels up to 40% or higher Anglo-Saxon admixture in 19th-century East Anglians would not surprise me. And whatever the 19th-century number turns out to be, Anglo-Saxon admixture in England likely would have been progressively higher going back in time toward before the Norman conquest.

Gene flow into England over the past millennium (from Wales, Scotland, Ireland, and France) will have tended to make the English look less Anglo-Saxon and more "Iron Age". The Scandinavian component in the Normans and particularly their followers was probably outweighed by the French; and subsequently France probably remained one of the main sources of continental immigrants into England at least down to the Huguenots. It's said around 50,000 Huguenots came to England (against a 17th-century English population of around 5 million). 1% does not sound like an especially large wave (and it's certainly not by the standards of modern mass immigration), but these immigrants were concentrated in south and east England:

Huguenot settlement was concentrated in London and the south, East Anglia and the Fens
Even a relative trickle of continental immigrants over the past 1000 years might have had a noticeable cumulative effect on the English gene pool, and Scottish, Welsh, and Irish gene flow into England over the past millennium is likely even more significant. 24% of British claim Irish ancestry recent enough to be aware of, including 77% of those in London. Around 10% of the UK population is estimated to have an Irish grandparent.

Filtering recent Irish immigration into Scotland might also lead to higher estimates of Anglo-Saxon admixture there, as well (though recent English immigration too would need to be excluded). Recent English immigration into Wales may mean the 20% Anglo-Saxon admixture estimate is significantly inflated (though going off the 20% estimate for modern Welsh I would guess 19th-century Welsh speakers had at least ~10% Anglo-Saxon-like admixture).

According to the authors:

The  genetic  analyses  described  above  add  significantly  to  our  picture  of  Anglo-­Saxon  migration  into  Britain.   In  the  cemetery  at  Oakington  we  see  evidence  even in  the  early  Anglo-­Saxon  period  for  a  genetically  mixed  but  culturally  Anglo-­Saxon  community 21,22 ,  in  contrast  to  claims  for  strong  segregation  between newcomers  and  indigenous  peoples 7 .  The  genomes  of  two  sequenced  individuals are  consistent  with  them  being  of  recent  immigrant  origin,  from  different continental  source  populations,  one  was  genetically  similar  to  native  Iron  Age samples,  and  the  fourth  was  an  admixed  individual,  indicating  intermarriage.   Despite  this,  their  graves  were  conspicuously  similar,  with  all  four  individuals buried  in  flexed  position,  and  with  similar  grave  furnishing.  Interestingly  the wealthiest  grave,  with  a  large  cruciform  brooch,  belonged  to  the  individual  of native  British  ancestry  (O4),  and  the  individual  without  grave  goods  was  one  of the  two  genetically  “foreign”  ones  (O2),  an  observation  consistent  with  isotope analysis  at  West  Heslerton  which  suggests  that  new  immigrants  were  frequently poorer   23,24 .  Given  this  mixing  apparent  around  500CE,  and  that  the  modern population  is  no  more  than  30%  of  Anglo-­Saxon  ancestry,  it  is  perhaps  surprising that  the  middle  Anglo-­Saxon  individuals  from  the  more  dispersed  field  cemetery in  Hinxton  all  look  genetically  consistent  with  unmixed  immigrant  ancestry.  One possibility  is  that  this  reflects  continued  immigration  until  at  least  the  Middle Saxon  period.  
In fact, there's nothing really inconsistent with the "Anglo-Saxon apartheid" paper in the mixed earlier samples and unmixed later samples. The Anglo-Saxon period samples tested here are all female. It's easy to imagine intermarriage rates may have been higher among the earliest Anglo-Saxon settlers, when their fraction of the total British population would have been smallest -- especially if females were to any degree underrepresented among the incoming Anglo-Saxons.

From the "Anglo-Saxon apartheid" paper (Evidence for an apartheid-like social structure in early Anglo-Saxon England):

We have only considered the effects of differences in ethnic reproductive advantage and inter-ethnic marriage rate on patterns of genetic variation. If there were no sex bias in the intermarriage rate, then we would expect these effects to be equal for the different genetic systems (mitochondrial DNA, Y-chromosome, X-chromosome, autosomes). However, part of the motivation for this study was to seek an explanation for the discrepancy between archaeological estimates of the size of the Anglo-Saxon migration (Härke 1998, 2002; Hills 2003) and estimates based on Y-chromosome data (Weale et al. 2002; Capelli et al. 2003). There are three further factors that could exacerbate replacement of indigenous Y-chromosomes. The first is that when intermarriage does occur the offspring may be more likely to assume the identity of the father, thus reducing the effective intermarriage rate, as it would affect patterns of Y-chromosome diversity. The second is that forced extra-marital matings are more likely to occur between Anglo-Saxon men and native British women than the reverse since, as the law codes of Ine indicate, the degree of punishment was determined by the social status of the victim. The third is based on the theory that relatively ‘good condition’ males tend to out-reproduce females of a similar condition, whereas relatively ‘poor condition’ females tend to out-reproduce their male counterparts (Trivers & Willard 1973). From this, a strategy of sex-biased parental investment, whereby relatively wealthy parents favour wealth transfer to their sons, should emerge (Hartung 1976). Such a phenomenon is supported by genealogical data (Boone 1986) and should lead to an asymmetric increase in the population frequency of Y-chromosomes carried by wealthy men, when compared to the other genetic systems.

The motivation for this study was to reconcile the discrepancy between, on the one hand, archaeological and historical ideas about the scale of the Anglo-Saxon immigration (Hills 2003), and on the other, estimates of the genetic contribution of the Anglo-Saxon immigrants to the modern English gene pool (Weale et al. 2002; Capelli et al. 2003). We have shown that this discrepancy can be resolved by the assumption of an apartheid-like social structure within a range of plausible values for interethnic marriage and socially driven reproductive advantage following immigration (Woolf 2004). Perhaps most strikingly, our model indicates that, by using plausible parameter values, the genetic contribution of an immigrant population can rise from less than 10% to more than 50% in as little as five generations, and certainly less than fifteen generations. Similar processes are likely to have shaped patterns of genetic variation in other ‘conquest societies’ of the period, and perhaps more recently (Carvajal-Carmona et al. 2000).

Reply to RCB on the evolution and adaptiveness of ethnocentric altruism

Continued from this discussion.

"you are unable to explain to a competent person why you believe what you believe."

I'm trying to be patient here, but I don't know how much better I can explain this. You either get it, or you don't. If you don't, you're not as competent as you believe; you either don't really understand the basic concepts we're talking about or have mental blocks when it comes to applying them to humans, and this is something you need to deal with yourself.

No matter how many times I explain this, you don't want to get it. Your starting point is that Salter can't be right; so when I explain to you how your reasoning is flawed, regardless of how many times we go through this or how many times I address a particular objection, your response is just to throw out additional confused reasoning, often forgetting things you previously agreed I was correct on and switching back to objections that have already been addressed.

The benefit of the ethnocentric altruism alleles comes from between-group selection, not within-group selection. Even in the first generation, an allele for ethnocentric altruism can potentially boost its odds of representation in future generations by, for example, reducing the chance of extinction of the group it's found in (whether by contributing to avoiding defeat and extermination by rival groups in an ancestral environment, or resisting replacement-level immigration in the modern world).

It makes no difference whether there is enough between-group relative to within-group competition at modern scales to maintain or grow this sort of variation in the long run (and certainly Hamilton speculated that self-sacrificing altruism would be found at higher levels in tribal people than in the long-civilized). In a particular instance of intergroup competition of the sort we're discussing, ethnocentric altruism alleles attuned to Hamilton's rule would by definition be adaptive.

This will always be true, regardless of scale, and regardless of how often the group is actually faced with the threat of intergroup competition. In the face of such a threat, the alleles (ones that enhance group competitiveness in a generalized fashion and are sensitive to cost, benefit, and relatedness) will be adaptive.

Your argument is somewhat analogous to claiming sickle-cell alleles can't be adaptive (or even exist in the first place!) in a malarial environment because their frequency would not increase in the long run in the absence of malaria. Even if malaria is nearly wiped out and the frequency of sickle-cell alleles begins to decline, this does not prove that if a mosquito with malaria does land on you you'd be better off not having a sickle-cell allele.

"Yes, the behaviors are polygenic. But all genes have to start at low frequency, and you have not explained how they get to high frequency"

Again: positive selection will come from intergroup competition. If your argument is that all relevant variants would be snuffed out immediately, leaving no variation on which group-level selection could act, this is of course absurd. Yet again: we're talking about very large numbers of weakly-selected variants, and a large surface on which new mutations can arise.

Crow and Aoki modeled group selection for polygenic behavioral traits. Again, it boils down to Hamilton's rule.

Group selection for a polygenic behavioral trait: a differential proliferation model [pdf]

Group selection for a polygenic behavioral trait: estimating the degree of population subdivision [pdf]

Our general approach is to use molecular markers, which are selected very weakly at most, as neutral indicators of population structure. GST gives us an appropriate description of the relevant aspect of the structure. By using Eq. 3 we can state the maximum value of cost/benefit of a quantitative trait if that trait is to increase in average value or frequency in the population. GST describes the present structure of the population; it does not tell us how it got that way. If this value has been roughly stable in the past, we could expect that traits with c/b up to this value would have increased in the population, assuming of course that such traits exist and have heritability greater than zero.

Empirically, ethnocentrism exists, and no doubt has since before we were humans. Empirically, ethnocentrism has heritability greater than zero.

  • Nature, nurture, and ethnocentrism in the Minnesota Twin Study [pdf]

  • Common Heritable Effects Underpin Concerns Over Norm Maintenance and In-Group Favoritism: Evidence From Genetic Analyses of Right-Wing Authoritarianism and Traditionalism [pdf]

  • Genetic evidence for multiple biological mechanisms underlying in-group favoritism [pdf]

Your issue is with reality, not with Salter or me.

"Of course, ethnic altruist genes could be maladaptive relics of the past, when groups were small. But Salter says they are adaptive now."

Again, see above.

And Salter never claims we are well-adapted to ethnic competition in the modern world. If he'd believed that to be the case, he would have had little reason to write the book. From the introduction:

On Genetic Interests is an attempt to answer the empirical question: How would an individual behave in order to be adaptive in the modern world? I adopt the neo-Darwinian meaning of adaptive, which is to maximize the survival chances of one’s genes. I begin by describing humans as an evolved species and thus as creatures for whom genetic continuity consists of personal reproduction or reproduction of kin. [. . .]

Humans can no longer rely on their instincts

There is nothing immutable or necessarily perfect about adaptations or the understanding, appetites and preferences they organize. Natural selection is constrained by evolutionary history and environment. It shapes bodies and behaviours in small increments by modifying existing species. Much in nature is badly designed, if one examines it from an engineer’s viewpoint. [. . .]

Like adaptations that advance them, proximate interests can be imperfect in promoting genetic interests. The main problem is the slowness of natural selection compared to the rapidity of technological and social change since the Neolithic. The inertia of adaptations can cause them to continue to promote proximate interests that no longer serve fitness. For most of humans’ evolutionary history, adaptations tracked slow-moving environmental change, including technological advances. In the species’ distant hominid and pre-hominid past, proximate interests that reduced an actor’s fitness were valued less and less as the genes that coded for such valuation failed to reproduce. For this reason, at most moments in time proximate interests have correlated with ultimate interests because the environment has changed so slowly that physiology and behaviour could keep track with it. Proximate and ultimate interests have been in equilibrium except where rapid changes in environment occurred. The equilibrium applying to humans has been upset in recent generations, so that we can no longer rely on subjectively designated proximate interests to serve our ultimate interest. We must rely more on science to perceive the causal links between the things we value and formulate synthetic goals based on that rational appraisal.

Proximate interests, often reflected in consciously held values, have become increasingly fallible guides to ultimate interests because modern humans live in a rapidly changing world. Humans evolved in small bands consisting of a few families, sometimes grouped into tribes numbering in the hundreds. For most of their evolutionary history humans made a living by hunting and gathering in largely natural environments. They lacked formal organization and hierarchy. Adults coordinated activities by negotiating simple demographic role specializations — by age and sex — on an egalitarian basis with familiar band members. Most information was common. Humans now live in societies numbering in the millions where the great majority of interactants are strangers or acquaintances. They make their living through a great diversity of occupations resulting in radical asymmetries in information. They live and work in largely man-made urban environments. They are formally organized into states administered by extended hierarchies of rank and resources actuated by authoritative commands, impersonal contracts enforced by the state authority, and powerful forms of indoctrination performed by universal education, centralized media and entertainment.

However, to the extent we are able to correctly reason about what would be adaptive in the context of intergroup competition, and act in accordance with this, we have the equivalent of our generalized ethnocentric altruism alleles.


NW-SE cline of brain volume in Europe

The authors of Modeling the 3D Geometry of the Cortical Surface with Genetic Ancestry mention:
In our group’s previous study, we found that area measures of cortical surface and total brain volumes of individuals of European descent in the United States correlate significantly with their ancestral geographic locations in Europe [ 9 ].
This 2011 study ("A Geographic Cline of Skull and Brain Morphology among Individuals of European Ancestry") is freely accessible:

Background: Human skull and brain morphology are strongly influenced by genetic factors, and skull size and shape vary worldwide. However, the relationship between specific brain morphology and genetically-determined ancestry is largely unknown. Methods: We used two independent data sets to characterize variation in skull and brain morphology among individuals of European ancestry. The first data set is a historical sample of 1,170 male skulls with 37 shape measurements drawn from 27 European populations. The second data set includes 626 North American individuals of European ancestry participating in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) with magnetic resonance imaging, height and weight, neurological diagnosis, and genome-wide single nucleotide polymorphism (SNP) data. Results: We found that both skull and brain morphological variation exhibit a population-genetic fingerprint among individuals of European ancestry. This fingerprint shows a Northwest to Southeast gradient, is independent of body size, and involves frontotemporal cortical regions. Conclusion: Our findings are consistent with prior evidence for gene flow in Europe due to historical population movements and indicate that genetic background should be considered in studies seeking to identify genes involved in human cortical development and neuropsychiatric disease. [. . .]

Apparently the two main groups being compared in the neuroimaging sample are Americans of Northwestern European ancestry and Ashkenazi Jews ("ADNI subjects are spread out primarily along a NW-SE axis and form two distinct clusters corresponding to NW European and Ashkenazi Jewish ancestry"):

To determine if brain morphometry exhibits similar geospatial population trends to the skull morphometry data, we estimated the ancestry of each individual in the ADNI sample using available genome-wide genotype data and confined attention to 626 individuals with a high probability of having European ancestry. In order to assign the European region of origin most likely to reflect the genetic background of each individual, genotypes from ADNI subjects were merged with publically available genotypes from 34 reference populations geographically distributed across Europe, and PCA was pursued. [. . .]

A plot of the first two principal components separates ADNI subjects into two main clusters: one overlaps NW populations and one lies SE of Europe ( fig. 3 a) and overlaps individuals with self-reported Ashkenazi Jewish ancestry (online suppl. fig. S5). [. . .]

We found that ADNI individuals with a NW ancestry are on average 4 cm taller than ADNI individuals with a SE or Ashkenazi Jewish ancestry (p = 7.3 ! 10–6 ), consistent with previously observed differences in height across Europe [30] . [. . .]

Intracranial and brain volumes and cortical surface area progressively increase with the amount of inferred NW European ancestry (fig. ​(fig.3b),3b), and these measures are approximately 5% larger in the 10% of individuals with the most NW European ancestry compared to the 10% with the most SE European ancestry. This percentage increase matches the percentage increase in cranial length and breadth observed along the same NW-SE geographic axis in the skull data set (fig. ​(fig.2b)2b) and cannot be attributed to a correlation with body size since we controlled for height and weight. This correlation involves specific – not global – brain morphology because hippocampal, basal ganglia, ventricular, and cerebellar volumes and average cortical thickness are not associated with NW-SE ancestry.

Next, we performed both a region of interest analysis and vertex-based tests across the cortex to test whether the surface area of specific cortical regions showed more significant association with the degree of NW-SE ancestry. We found that cortical surface area predominantly in the frontal and temporal lobes from both hemispheres is significantly associated (online suppl. table S4) and is 4–9% larger among 10% of individuals with the most NW European ancestry compared to 10% with the most SE European ancestry. We found a similar frontotemporal pattern of association with the degree of NW-SE ancestry with a vertex-based analysis (fig. ​(fig.4;4; online suppl. fig. S6).

[. . .] the existence of genetic and craniometric clines in modern European populations suggests at least two theories: (1) pre-historic population movements made such a dominant contribution to the structure of genetic variation in Europe that more recent gene flow has not masked it, and (2) local environmental factors and selection generated clinal variation or acted to restore clinal variation after gene flow occurred. One intriguing possibility for such an environmental factor is the cultural conditions associated with possessing agricultural technologies, e.g. sedentarism, altered diet including milk consumption [40] , and new disease exposures [41] . As these technologies spread progressively from SE to NW Europe over several 1,000 years [33] , natural selection may have acted either directly or indirectly to alter brain morphology, thus creating the clinal variation found in this study.

Plots of cranial measures from this study (left) and map of head size from Coon's 1939 book The Races of Europe (right):

The trend observed here is also consistent with that reported by Maurice Fishberg over a century ago in The Jews: A Study of Race and Environment:

One of the methods of determining the volume of the brain case, and approximately the weight of the brain, is the determination of the cranial capacity. Very few direct measurements of this kind have been taken, because only few Jewish skulls have found their way into anthropological museums, where they could be studied carefully. But from the few studies of this character that have been made, it appears that the Jews are somewhat at a disadvantage. Lombroso's studies of the Jews in Turin, Italy, which were made in an indirect fashion, showed that the Jews have a smaller cranial capacity than the Catholics of that city.2 Weinberg collected measurements of seventeen Jewish skulls in various museums of Europe, which were made properly, and are not approximations. The average cranial capacity was 1421 c.cm., which is about thirty to forty c.cm. below the average cranial capacity of the population of Europe. Of course the small number of skulls thus measured is not sufficient to draw positive conclusions.

As to the weight of the brain, there are also very few observations on record. The author knows only of twentythree Jewish brains reported by Giltchenko,3 four by Weisbach,4 and three by Weinberg.5 The average weight of these brains, as calculated by Weinberg, was 1320.4 gm. Since the average weight of the brain of the European is 1350 gms., the brain of Jews is rather lighter by 30 gms. , or nearly one ounce. Considering that the Jews are shorter of stature than the average Europeans, it would be expected that their brain should also be smaller. But, as Weinberg points out, the average for Germans was found to be 8.22 gm. of brain tissue for each centimetre of stature, while for the Jews it is only 8.05 gms. This shows the Jewish brain lighter not only absolutely, but also relatively.

Evolutionary significance of Denisovan admixture in Oceanians

Investigating the Evolutionary Importance of Denisovan Introgressions in Papua New Guineans and Australians
Previous research reported that Papua New Guineans (PNG) and Australians contain introgressions from Denisovans. Here we present a genome-wide analysis of Denisovan introgressions in PNG and Australians. We firstly developed a two-phase method to detect Denisovan introgressions from whole-genome sequencing data. This method has relatively high detection power (79.74%) and low false positive rate (2.44%) based on simulations. Using this method, we identified 1.34 Gb of Denisovan introgressions from sixteen PNG and four Australian genomes, in which we identified 38,877 Denisovan introgressive alleles (DIAs). We found that 78 Denisovan introgressions were under positive selection. Genes located in the 78 introgressions are related to evolutionarily important functions, such as spermatogenesis, fertilization, cold acclimation, circadian rhythm, development of brain, neural tube, face, and olfactory pit, immunity, etc. We also found that 121 DIAs are missense. Genes harboring the 121 missense DIAs are also related to evolutionarily important functions, such as female pregnancy, development of face, lung, heart, skin, nervous system, and male gonad, visual and smell perception, response to heat, pain, hypoxia, and UV, lipid transport, metabolism, blood coagulation, wound healing, aging, etc. Taken together, this study suggests that Denisovan introgressions in PNG and Australians are evolutionarily important, and may help PNG and Australians in local adaptation. In this study, we also proposed a method that could efficiently identify archaic hominin introgressions in modern non-African genomes.

Racial differences in brain shape

A press release:

Researchers at the University of California, San Diego and the School of Medicine have found that the three-dimensional shape of the cerebral cortex -- the wrinkled outer layer of the brain controlling many functions of thinking and sensation -- strongly correlates with ancestral background.
Modeling the 3D Geometry of the Cortical Surface with Genetic Ancestry

Knowing how the human brain is shaped by migration and admixture is a critical step in studying human evolution [ 1, 2 ], as well as in preventing the bias of hidden population structure in brain research [ 3, 4 ]. [. . .] The geometry of the cortical surface contains richer information about ancestry than the areal variability of the cortical surface, independent of total brain volumes. Besides explaining more ancestry variance than other brain imaging measurements, the 3D geometry of the cortical surface further characterizes distinct regional patterns in the folding and gyrification of the human brain associated with each ancestral lineage.

Chris Stringer on the possibility of a Eurasian origin for Homo heidelbergensis

Who is Homo heidelbergensis?

H. heidelbergensis is a critical human species in the Middle Pleistocene (∼130–780 thousand years ago (ka)). We know from several beautifully preserved crania that this species had a large brain, within the lower range of modern human variation, and a less robust face than early fossil humans. We know from their long bones that they were tall, strong people. From their associated archaeology we know they were capable of producing beautiful tools such as the large handaxes found in huge numbers at Boxgrove in Sussex. But there are many unanswered questions: who exactly belongs to the species Homo heidelbergensis, where did they live, how do they fit into the human family tree, and are they a separate species at all? [. . .]

Are they our ancestors? African H. heidelbergensis material, such as Broken Hill, shares numerous features with European fossils such as Petralona, leading many to group them together. As long as Mauer is also included, this taxon can be named H. heidelbergensis. Proponents of this wide concept of H. heidelbergensis assert that the mosaic of primitive and derived features shared by this group of fossils is unique, with few traits linking them exclusively to either modern humans or Neanderthals ( Figure 1B). H. heidelbergensis is thus hypothesised to be the last common ancestor of both Neanderthals in Eurasia and H. sapiens in Africa. This scenario is probably the most popular and well supported at present. [. . .]

The geographic origin of H. heidelbergensis is still unknown, but the early fossils from Asia suggest that continent is as likely a place of origin as Europe or Africa at the moment. An Asian origin for a species directly ancestral to our own would certainly shake up the current rather Afro-centric view of our evolution.


Inbreeding and inclusive fitness

Inbreeding avoidance, tolerance, or preference in animals?
The widespread presumption that inbreeding depression will inevitably cause net selection for inbreeding avoidance ignores the inclusive fitness benefit of inbreeding that exists because parents are more closely related to inbred offspring than to outbred offspring. This increased relatedness arises because inbred offspring, by definition, inherit alleles from one parent that are identical by descent to those carried by, and potentially inherited from, the other parent. Inbreeding thereby increases the expected proportion of alleles that any one parent shares with its offspring, including alleles favouring inbreeding [10,24,25]. This inclusive fitness benefit underpins extensive theory predicting the evolution of self-fertilisation in plants [10,25–27]. That this same benefit could also cause the evolution of biparental inbreeding was suggested three decades ago (Box 1) [28,29], but remained widely ignored by animal ecologists. The assumption that inbreeding depression inevitably causes selection for inbreeding avoidance continued to pervade hypotheses explaining dispersal, mate choice, and polyandry [3,5,6,11,30–32]. Recent theory has re-emphasised that biparental inbreeding could be adaptive, even given inbreeding depression, with the inclusive fitness benefit phrased as ‘helping relatives to breed’ and hence kin selection [12,13,33].
What Happens after Inbreeding Avoidance? Inbreeding by Rejected Relatives and the Inclusive Fitness Benefit of Inbreeding Avoidance
The fitness costs associated with inbreeding, primarily inbreeding depression in resulting offspring, have caused a widespread assumption among animal ecologists that inbreeding avoidance must be adaptive [10, 21, 22]. Meanwhile, empirical studies have reported a lack of inbreeding avoidance [34, 42–47], or even an apparent preference for inbreeding [48–52], causing a mismatch between expectations and data [27]. This mismatch is partially resolved by basic conceptual models of biparental inbreeding that imply that the inclusive fitness benefit of inbreeding might cause inbreeding tolerance or preference to be adaptive even given inbreeding depression in offspring fitness, and that predict sexual conflict over inbreeding [24–28]. [. . .]

Our models imply that the inclusive fitness costs and benefits of inbreeding versus avoiding inbreeding will vary among individuals depending on their interactions with multiple different relatives of both sexes, and on the degree to which focal individuals are themselves inbred. Understanding these costs and benefits and their combined consequences for the evolution of inbreeding strategies therefore requires consideration of not only the relatedness of an individual to its potential mate(s), but also the relatedness between the individual and the subsequent mates of rejected relatives. Knowledge of the distribution of relatedness within a population is therefore likely to be critical for understanding the evolution of inbreeding strategies. This distribution will in turn depend on the distribution of relatedness in previous generations and on previously realised inbreeding strategies and inbreeding loads, thereby generating complex feedbacks between inbreeding strategy, load, and relatedness. [. . .]

Sexual conflict and interactions among multiple non-self relatives are particular to biparental reproduction rather than self-fertilisation, but both types of inbreeding increase the expression of inbreeding load causing inbreeding depression in offspring [1, 2, 7, 12]. Inbreeding depression may decrease inbreeding load by exposing deleterious homozygous recessive alleles to selection [9, 71]. Resulting purging of deleterious recessive alleles may in turn affect the inclusive fitness benefit of inbreeding versus avoiding inbreeding causing inbreeding strategy and inbreeding load to coevolve [12, 72, 73]. The consequences of this coevolution have been modelled extensively with respect to outcrossing versus selfing [12, 18, 72, 74–76], but have not yet been modelled for the evolution of biparental inbreeding strategies [10]. Future theoretical developments will therefore need to explicitly consider coevolution between biparental inbreeding strategy and inbreeding load.

Predictive models of biparental inbreeding evolution cannot be simple, but their complexity need not preclude generality [77]. Tractable approaches for developing inbreeding theory might include game-theoretic models, or individual-based models that explicitly track ancestry and inbreeding load, and thereby incorporate feedbacks among relatedness, load, and inbreeding strategy.


David Agus: inbred retard?

Discussing a recent study (Directional dominance on stature and cognition in diverse human populations) that found an effect for runs of homozygosity on height and IQ within populations, Greg Cochran notes:
Some retards (British papers) have been spinning this as saying that there are big benefits to mixed-race marriage. Untrue: to avoid lots of ROH (runs of homozygosity), just marry someone who isn’t from the same isolated population as you. We’re talking outside the valley or across the river : intercontinental travel is not necessary. Now there might be a degree of hybrid vigor in some distant crosses (currently unclear) – but likely not enough to compensate for someone coming from a group that has low trait values. Marry a Pygmy and your kids are going to be short. Marry someone from a population whose average IQ is below 90 (much of the world) and your kids will on average be less smart.
CBS medical contributor David Agus (who, wikipedia informs us, "graduated cum laude in molecular biology from Princeton University and received his medical degree from the University of Pennsylvania School of Medicine in 1991") promotes this misinterpretation of the study in a segment on CBS This Morning:

Do kids from mixed genetic backgrounds have an advantage?

Additionally, although one would hope someone who majored in molecular biology at Princeton and co-founded a personal genomics company would know that any benefits from outcrossing will fully accrue in the first generation, Agus gleefully urges the viewer to imagine how much "taller and smarter" children will be if "people of different backgrounds" continue interbreeding generation after generation.

It's a pretty interesting study that tells us a lot because this is really the first couple generations where people of different backgrounds are having children and if this happens in one, one generation children are 1.2 cm shorter, think of if this continues to happen, so, taller and smarter.

Curiously, Agus, the grandson of a rabbi, married a pre-Connie Chung daughter of Maury Povich. That is, Agus chose to mate with a member of the same rather inbred narrow ethnic group as himself. But I'm sure now that he's aware of this study (confused though he may be about it) and excited about the eugenic prospects of racial mixing, he's urged his own children to marry Africans, with that same gleeful look in his eyes.

It’s Sunday night, and Agus is at Jerusalem’s Mamilla Hotel. He just arrived for the Global Forum, a gathering of 70 of the world’s thinkers hosted by Israel’s National Library, to discuss how the People of the Book can use their ancient lore for contemporary needs.

It was Shimon Peres, the honorary chairman of the event, who convinced Agus to attend. Agus and Peres are friends – though he’s not the nonagenarian’s doctor – and the two meet every six months or so. This time, Agus will be discussing Maimonides at the National Library, from the perspective of what he, Agus, believes.

But first he had to go back and read some of the good doctor’s words. It’s been a long time since Agus studied Maimonides at Philadelphia’s Akiba Hebrew Academy. What he found resonated. [. . .]

Now Agus combines teaching, research and patient work, along with spending a lot of time at places like the World Economic Forum, the Aspen Ideas Festival and TEDMED – TED for the health field. He’s also at the CBS studio at 4 a.m., several mornings per week.

“You get a passion to change things, and I decided I don’t care if I’m uncomfortable on camera,” said Agus, who calls himself an introvert by nature. “I need to be a role model and it’s awkward, but you have to do it, over and over again. I get to talk to four million people every morning on CBS. I can just talk, I can call a spade a spade. I look at my patients losing their lives on a daily basis, so I’ve got nothing to lose.”

[Steve Jobs’ ex-doctor is in, and he’s quoting Maimonides. http://www.timesofisrael.com/steve-jobs-ex-doctor-is-in-and-hes-quoting-maimonides/]

JayMan continues to talk about things he doesn't understand

In this episode, he's back to insisting "ethnic genetic interests" (which despite having been corrected multiple times he's still unable to correctly define) are "bunk" (emphasis in original):
However, common among people who have a superficial and/or selective understanding of heritable group differences is belief in conveniently inaccurate claims. One of these erroneous ideas that White nationalists in particular have latched on to is the belief in “ethnic genetic interests” – that is, that kin selection has led individuals to favor people of their own race/ethnic group over others. This of course is bunk. Natural selection doesn’t work that way, since individuals within an ethnic group aren’t closely related enough for this to work. This has been explained repeatedly, lately by Misdreavus:
It is impossible for such a thing as a “race altruist gene” to evolve, because sacrificing yourself on behalf of strangers does nothing to increase the frequency of the gene under any set of circumstances. It doesn’t matter if the frequency of a such a gene “magically” originated with a frequency of 4 in 10 Chinese people. The Chinese who don’t have the gene, on average, would have a higher fitness, resulting in the frequency decreasing monotonically over time.
He continues to argue there, which is worth a read for anyone seriously interested in the matter.

After anyone seriously interested in the matter gets done studying the confused rantings of JayMan's gay sidekick, I would recommend they at least take a few minutes to skim the work of the man who coined the term "ethnic genetic interests". Doing so would have saved JayMan and misdreavus at least some measure of embarrassment.

A copy of Frank Salter's On Genetic Interests: Family, Ethnicity, And Humanity In An Age Of Mass Migration is freely available online.

If you want to talk about ethnic genetic interests, read it.

The actual definition of ethnic genetic interests

Frank Salter defines "ethnic genetic interests" as:

The number of copies of a random individual's distinctive genes in his or her ethny, not counting the copies in kin. The size of ethnic genetic interest is relative to the kinship of genetic competitors. When competitors are closely related ethnies, the interest can be relatively small. When competitors are distantly related, especially from different geographical races, ethnic genetic interest can be many orders of magnitude greater than familial genetic interests.

To deny that ethnic genetic interests exist is to deny that human population structure exists (or to hilariously misunderstand basic population genetics). Ethnic genetic interests exist regardless of whether or not one believes group selection has played any role in human evolution and regardless of whether or not people naturally favor others from their own group.

The issue of the degree to which group selection or kin selection favored the evolution of ethnocentric altruism in humans has no bearing on the reality of ethnic genetic interests. It's a separate issue, on which JayMan/misdreavus are also wrong (one can debate the issue, but not on the confused grounds JayMan and misdreavus have attempted to debate it).

Misdreavus's confusion about coefficients of relatedness

One area of confusion for misdreavus in the linked thread:

The coefficient of relatedness between a Swede and a non-related Swede is zero. The coefficient of relatedness between a Swede and a black African is also zero. You simply do not seem to understand this.
I replied at the time:

This is exactly the misapprehension I just got done correcting for JayMan: http://racehist.blogspot.com/2015/02/kinship-coefficients-and-ethnic-genetic.html

The coefficient of relationship is simply twice the coefficient of inbreeding between the hypothetical children of two individuals. Inbreeding is defined relative to some population. It’s often convenient to disregard non-recent inbreeding in calculating coefficients of relationship, but this only makes sense with respect to a particular [approximately random-breeding] population, and, holding the base population constant, a Swede absolutely does not have the same coefficient of relationship to a sub-Saharan as to another Swede. Nor is there any difference in kind between the type of relatedness indicated through Fst and the type shared by close family members.

Even after having it explained to them again, Misdreavus (and apparently JayMan) still failed to understand this very basic concept.

Misdreavus's confusion about the viability of genes for altruism

This is another extremely basic issue: frequencies of genes harmful to an individual's fitness with respect to his group can increase globally if his group expands relative to other groups. If misdreavus had read and understood pretty much anything written about altruism and kin selection or group selection within the past half century, he would have grasped this.

If groups with high frequencies of ethnocentric people expand at the expense of groups with low ethnocentrism, genes for ethnocentric altruism can increase in frequency.

Even misdreavus's (anti-group-selectionist) idol understands this (or did at one point):

Imagine that in much of history, people lived in small groups that often fought with their neighbors. In that sort of situation, selection for group altruism is at least possible, since the group is full of close relatives, while the opponents are less closely related. Both sides are probably members of the same broad ethnic group or race, but that doesn’t matter : only the kinship coefficients matter.

Self-reported vs. genetic ancestry in a large US cohort

Characterizing Race/Ethnicity and Genetic Ancestry for 100,000 Subjects in the Genetic Epidemiology Research on Adult Health and Aging (GERA) Cohort (free full text; supplementary material)
Using genome-wide genotypes, we characterized the genetic structure of 103,006 participants in the Kaiser Permanente Northern California multi-ethnic Genetic Epidemiology Research on Adult Health and Aging (GERA) Cohort and analyzed the relationship to self-reported race/ethnicity. Participants endorsed any of 23 race/ethnicity/nationality categories, which were collapsed into 7 major race/ethnicity groups. By self-report the cohort is 80.8% white and 19.2% minority; 93.8% endorsed a single race/ethnicity group, while 6.2% endorsed two or more. PC and admixture analyses were generally consistent with prior studies. Approximately 17% of subjects had genetic ancestry from more than one continent, and 12% were genetically admixed considering only non-adjacent geographical origins. Self-reported whites were spread on a continuum along the first two PCs, indicating extensive mixing among European nationalities. Self-identified East Asian nationalities correlated with genetic clustering, consistent with extensive endogamy. Individuals of mixed East Asian-European genetic ancestry were easily identified; we also observed a modest amount of European genetic ancestry in individuals self-identified as Filipinos. Self-reported African Americans and Latinos showed extensive European and African genetic ancestry, and Native American genetic ancestry for the latter. Among 3,741 genetically-identified parent-child pairs, 93% were concordant for self-reported race/ethnicity; among 2,018 genetically-identified full-sib pairs, 96% were concordant; the lower rate for parent-child pairs was largely due to inter-marriage. The parent-child pairs revealed a trend towards increasing exogamy over time; the presence in the cohort of individuals endorsing multiple race/ethnicity categories, creates interesting challenges and future opportunities for genetic epidemiologic studies. [. . .]

The initial analysis showed, as expected, a clear Ashkenazi cluster and a larger cluster depicting the northwest-southeast European cline (Price et al. 2008; Tian et al. 2008c).

In this Northern California sample, less than 1% of the self-identified "European/West Asian" group showed evidence of Amerindian ancestry, and less than half a percent showed evidence of black admixture.

As expected, all individuals who self-identified as European/West Asian had evidence of European/West Asian genetic ancestry. The next largest genetic ancestry component in this group was South Asian (4.3%), primarily attributable to individuals of West Asian ethnicity. Because there is a continuum of genetic ancestry from Europe to West Asia, Central/ South Asia to East Asia, genetic overlap exists for individuals whose national origins are geographically between these divisions (Li et al. 2008). Nearly 1% of this group also had evidence of Native American genetic ancestry, while a smaller fraction had evidence of African or East Asian genetic ancestry (0.3% and 0.4%, respectively). Nearly all individuals (99.7%) self-reporting African/African American race/ethnicity had evidence of African genetic ancestry; 91% also had evidence of European genetic ancestry, consistent with broad European admixture among African Americans. Native American and East Asian genetic ancestry occurred in this group at a similar low level as observed in the Europeans/West Asians (1.3% and 0.5%, respectively). Among self-reported East Asians, all had evidence of East Asian genetic ancestry; a sizeable proportion (21.7%) also had evidence of Pacific Islander genetic ancestry, but this likely represents difficulty in differentiating East Asian and Pacific Islander genetic ancestry. A modest subgroup (3.4%) had evidence of European/West Asian genetic ancestry (majority are self-reported Filipinos), while small proportions had evidence of African or Native American genetic ancestry (0.1% and 0.5%, respectively). Among the Latinos, nearly all had evidence of European/West Asian genetic ancestry; a similar high proportion (94.2%) had evidence of Native American genetic ancestry, and an additional 27.7% had evidence of African ancestry. A substantial number of self-reported Pacific Islanders had evidence of East Asian genetic ancestry (91.3%) in addition to Pacific Islander genetic ancestry (66.3%); these results are again likely due to close genetic similarity between East Asians and Pacific Islanders. There is also evidence of substantial European/West Asian and South Asian genetic ancestry in this group (57.6% and 26.1%, respectively). The former reflects a high rate of European admixture among some self-reported Pacific Islander groups, while the latter likely reflects Fijians of Indian origin.

Why JayMan is fat

The self-control consequences of political ideology
Evidence from three studies reveals a critical difference in self-control as a function of political ideology. Specifically, greater endorsement of political conservatism (versus liberalism) was associated with greater attention regulation and task persistence. Moreover, this relationship is shown to stem from varying beliefs in freewill; specifically, the association between political ideology and self-control is mediated by differences in the extent to which belief in freewill is endorsed, is independent of task performance or motivation, and is reversed when freewill is perceived to impede (rather than enhance) self-control. Collectively, these findings offer insight into the self-control consequences of political ideology by detailing conditions under which conservatives and liberals are better suited to engage in self-control and outlining the role of freewill beliefs in determining these conditions.
Why conservatives might be better at dieting than liberals
"Conservatives tend to believe they had a greater control over their outcomes, and that was predicting how they did on the test," said Joshua Clarkson, a consumer psychologist at the University of Cincinnati and the lead author of the paper.

Criminality and intelligence in Finland

James Thompson summarizes a recent paper ("Intelligence and criminal behavior in a total birth cohort: An examination of functional form, dimensions of intelligence, and the nature of offending"):

They found that lower levels of intelligence are associated with greater levels of offending, that the IQ-offending association is mostly linear, with some curvilinear aspects at highest and lowest levels, and that the pattern is consistent across multiple measures of intelligence and offending. In some ways this is exactly as predicted and already observed, since the available literature shows that individuals with lower IQ are more likely to engage in criminal behaviour. Criminal offending was measured with nine different indicators from official records and intelligence was measured using three subscales (verbal, mathematical, and spatial reasoning) as well as a composite measure. The results show consistent evidence of mostly linear patterns, with some indication of curvilinear associations at the very lowest and the very highest ranges of intellectual ability. [. . .]

Note that violent crime is an order of magnitude higher in the bottom 20% of the population by ability than the top 20% of population by ability. The pattern is generally a linear one. The subscales of intelligence show the same pattern, though perhaps the spatial scores show a slightly less pronounced differential effect.

So, why do dull minds carry out criminal acts? The main effect is driven by general intelligence, so that raises a number of possibilities, in that highly g-loaded factors such as deficits in executive functions, including inhibition, processing speed, and attention are potentially linked to criminal behaviour. People with higher levels of intelligence are more dependable ( Deary et al., 2008b) and conscientious ( Luciano, Wainwright, Wright, & Martin, 2006), suggesting that they are more likely to think about the moral consequences of their actions compared to individuals with lower levels of intelligence. People with lower intelligence have been found to act more impulsively ( de Wit et al., 2007 and Funder and Block, 1989). People with lower levels of impulse control and related constructs, such as low self-control, have also been found to be significantly more likely to engage in various forms of criminal and antisocial behavior ( Gottfredson and Hirschi, 1990,Moffitt et al., 2011 and Pratt and Cullen, 2000). While only preliminary, current research suggests that lower levels of intelligence reduces the ability to weigh the costs and benefits of individual action, resulting in a greater propensity to make impulsive decisions, which in some cases involve illegal behaviour.


The ancestry and affiliations of Kennewick Man

Kennewick Man ancient DNA. The paper is openly accessible. Results pretty much as I expected.
We find that Kennewick Man is closer to modern Native Americans than to any other population worldwide.
The paper is marred by strained, politically-motivated attempts to tie Kennewick Man specifically to "the Confederated Tribes of the Colville Reservation (Colville), one of the five tribes claiming Kennewick Man". So those interested in aboriginal American population structure are probably better off ignoring much of the authors's narrative and looking directly at the data.

Variation and signatures of selection on the human face

Variation and signatures of selection on the human face. [Open access]

J Hum Evol. 2014 Oct;75:143-52

Authors: Guo J, Tan J, Yang Y, Zhou H, Hu S, Hashan A, Bahaxar N, Xu S, Weaver TD, Jin L, Stoneking M, Tang K


There has been much debate about why humans throughout the world differ in facial form. Previous studies of human skull morphology found levels of among-population differentiation that were comparable to those of neutral genetic markers, suggesting that genetic drift (neutral processes) played an important role in influencing facial differentiation. However, variation in soft-tissue morphology has not been studied in detail. In this study, we analyzed high-resolution 3D images of soft-tissue facial form in four Eurasian populations: Han Chinese, Tibetans, Uyghur and Europeans. A novel method was used to establish a high-density alignment across all of the faces, allowing facial diversity to be examined at an unprecedented resolution. These data exhibit signatures of population structure and history. However, among-population differentiation was higher for soft-tissue facial form than for genome-wide genetic loci, and high-resolution analyses reveal that the nose, brow area and cheekbones exhibit particularly strong signals of differentiation (Qst estimates: 0.3-0.8) between Europeans and Han Chinese. Our results suggest that local adaptation and/or sexual selection have been important in shaping human soft-tissue facial morphology. [. . .]

The Qpc values found in the nose and brow area between Europeans and Han Chinese approach the high differentiation reported for skin pigmentation (Relethford, 2004b). This suggests that strong local adaptation may have shaped these facial features (Myles et al., 2007). For the nose, strong correlations have been found between the nasal index and temperature/humidity, supporting climate adaptation as the major selective force (Thomson and Buxton, 1923, Davies, 1932, Weiner, 1954, Wolpoff, 1968, Hiernaux and Froment, 1976, Crognier, 1981 and Franciscus and Long, 1991). Models simulating airflow dynamics demonstrated that bigger nasal volumes, narrower shapes and downwardly pointing nares might enhance the airflow exposure of the mucosa and thereby facilitate the heating and humidification of the air (Churchill et al., 2004). The European nose shape thus may have resulted from adaptation to a colder climate. The relatively enlarged brow area in Europeans has also been noted previously (Russell et al., 1985). It has been argued that brow area size is positively correlated with the magnitude of the mechanical stresses resulting from mastication, so brow area shape differentiation (SOM, Fig. S11) could be the result of dietary differences (Russell et al., 1985). Adaptation to specific diets (Hubbe et al., 2009) and climate adaptation (Coon et al., 1950) have been hypothesized to explain the expanded zygomatics in Asians.

In addition to natural selection, sexual selection may also have played a major role in shaping interpopulation variation in the human face. Selective mate choice based on facial appearance in humans is well documented as a universal condition in global populations (Wells et al., 2009). However, whether and to what extent sexual selection shaped human facial morphology has rarely been investigated. Fisher's runaway sexual selection model suggests that a positive feedback loop composed of an arbitrary trait involving appearance, and the accidental preference of this trait in the opposite sex, could initiate a powerful sexual selection process (Fisher, 1958). It is therefore possible that some of the strong differentiation signals involving the soft-tissue facial form may have resulted from sexual selection. Further studies that combine high-resolution 3D face analysis, studies of human behavior, and genetic analyses are necessary to delineate the possible roles of local adaptation versus sexual selection in explaining the relatively large between-population differentiation that we find for soft-tissues of the human face.

Persistence of Lombard Y chromosomes in old Northern Italian families?

Traces of medieval migrations in a socially stratified population from Northern Italy. Evidence from uniparental markers and deep-rooted pedigrees.

Heredity (Edinb). 2015 Feb;114(2):155-62

Authors: Boattini A, Sarno S, Pedrini P, Medoro C, Carta M, Tucci S, Ferri G, Alù M, Luiselli D, Pettener D


Social and cultural factors had a critical role in determining the genetic structure of Europe. Therefore, socially stratified populations may help to focus on specific episodes of European demographic history. In this study, we use uniparental markers to analyse the genetic structure of Partecipanza in San Giovanni in Persiceto (Northern Italy), a peculiar institution whose origins date back to the Middle Ages and whose members form the patrilineal descent of a group of founder families. From a maternal point of view (mtDNA), Partecipanza is genetically homogeneous with the rest of the population. However, we observed a significant differentiation for Y-chromosomes. In addition, by comparing 17 Y-STR profiles with deep-rooted paternal pedigrees, we estimated a Y-STR mutation rate equal to 3.90 * 10(-3) mutations per STR per generation and an average generation duration time of 33.38 years. When we used these values for tentative dating, we estimated 1300-600 years ago for the origins of the Partecipanza. These results, together with a peculiar Y-chromosomal composition and historical evidence, suggest that Germanic populations (Lombards in particular) settled in the area during the Migration Period (400-800 AD, approximately) and may have had an important role in the foundation of this community.


Prenatal exposure to tylenol lowers testosterone and sperm counts

Given that "paracetamol sales in Denmark have been estimated among the highest in the world" and paracetamol consumption is evidently much lower in Finland, this may turn out to be a substantial part of the explanation of this phenomenon: East–West gradient in semen quality in the Nordic–Baltic area: a study of men from the general population in Denmark, Norway, Estonia and Finland

There's been epidemiological evidence pointing in this direction for years, but more direct evidence, from a xenograft model, has now been reported.

Pregnant women are advised to seek medical advice if they need paracetamol for more than one day

Pregnant women are being advised to see their doctor if they need to take paracetamol for more than a day, after researchers found in an animal study that prolonged use of the analgesic reduced the production of testosterone.1

Four previous studies have linked the use of paracetamol in pregnancy with an increased risk of cryptorchidism in male babies, but a causal effect has not been shown because it is not possible to test the association in women. To overcome this, researchers from the University of Edinburgh developed an animal model using castrated mice, into which they grafted human testicular tissue. These grafts have been shown to mimic how the developing testes grow and function in pregnancy.

Prolonged exposure to acetaminophen reduces testosterone production by the human fetal testis in a xenograft model
Most common male reproductive disorders are linked to lower testosterone exposure in fetal life, although the factors responsible for suppressing fetal testosterone remain largely unknown. Protracted use of acetaminophen during pregnancy is associated with increased risk of cryptorchidism in sons, but effects on fetal testosterone production have not been demonstrated. We used a validated xenograft model to expose human fetal testes to clinically relevant doses and regimens of acetaminophen. Exposure to a therapeutic dose of acetaminophen for 7 days significantly reduced plasma testosterone (45% reduction; P = 0.025) and seminal vesicle weight (a biomarker of androgen exposure; 18% reduction; P = 0.005) in castrate host mice bearing human fetal testis xenografts, whereas acetaminophen exposure for just 1 day did not alter either parameter. Plasma acetaminophen concentrations (at 1 hour after the final dose) in exposed host mice were substantially below those reported in humans after a therapeutic oral dose. Subsequent in utero exposure studies in rats indicated that the acetaminophen-induced reduction in testosterone likely results from reduced expression of key steroidogenic enzymes (Cyp11a1, Cyp17a1). Our results suggest that protracted use of acetaminophen (1 week) may suppress fetal testosterone production, which could have adverse consequences. Further studies are required to establish the dose-response and treatment-duration relationships to delineate the maximum dose and treatment period without this adverse effect.

People of the British Isles Project talk

(I'm not convinced by the approach they took to estimating Anglo-Saxon admixture proportions; but the intra-UK clustering discussed starting around ~14:30 should be objective enough.)

Garrett Hellenthal - The Genetic History of the United Kingdom: the POBI project

Garrett presents results from the People of the British Isles (POBI) project, an exploration of the fine-scale genetic architecture of the United Kingdom. Using the DNA of individuals sampled across England, Northern Ireland, Scotland and Wales, Garrett illustrates the striking correlation between an individual's genetics and their geographic origins. Furthermore, by comparing the DNA of UK individuals to that of individuals sampled from continental Europe, we identify clear differences in ancestry among different geographic regions of the UK, reflecting the genetic imprint of the Anglo-Saxon and Norwegian Viking migrations from several centuries ago.

Gender and Politics Among Anthropologists in the Units of Selection Debate

Gender and Politics Among Anthropologists in the Units of Selection Debate:
In recent years evolutionary theorists have been engaged in a protracted and bitter disagreement concerning how natural selection affects units such as genes, individuals, kin groups, and groups. Central to this debate has been whether selective pressures affecting group success can trump the selective pressures that confer advantage at the individual level. In short, there has been a debate about the utility of group selection, with noted theorist Steven Pinker calling the concept useless for the social sciences. We surveyed 175 evolutionary anthropologists to ascertain where they stood in the debate. We found that most were receptive to group selection, especially in the case of cultural group selection. The survey also revealed that liberals and conservatives, and males and females, all displayed significant differences of opinion concerning which selective forces were important in humanity’s prehistory. We conclude by interpreting these findings in the context of recent research in political psychology.
Peter Turchin:
A particularly interesting recent study is the one by William Yaworsky, Mark Horowitz, and Kenneth Kickham, Gender and Politics among Anthropologists in the Units of Selection Debate, published a month ago in Biological Theory. It’s interesting because it addresses the question of group versus kin selection, which is of course one of the most dividing issues in evolutionary science.

Yaworsky and colleagues obtained 175 surveys from evolutionary anthropologists who served faculty in graduate programs in various universities (which means that they are training their own graduate students). Their analysis of the questionnaires showed that there were very striking differences between different groups of anthropologists. Liberals were much more likely to disagree with the statement that tribal conflict was a principal evolutionary force that shaped human behavior. Conservatives, on the other hand, thought that tribalism was a fundamental human trait. They also tended to agree with the notion that homicide was frequent in early human societies.

The differences between male and female evolutionary anthropologists were even stronger than between different parties. Women were very resistant to the ideas that tribal conflict was an important selective force and that homicide was common in prehistory. [. . .]

And I expect that the questions of the importance of between-group competition and the frequency of lethal violence in prehistory will eventually achieve the same level of consensus. It may take many decades, but my hunch is that it will happen more quickly than that.

In fact, it’s already happening. The data of Yaworsky and colleagues show that 80 percent of respondents disagree with Pinker’s assertion that group selection is a useless concept. A similar proportion thinks that group selection is an important process, and 55 percent consider group selection as a more important process than kin selection. In contrast, among the professors who trained this cohort of respondents, the previous generation, only 8 percent were strongly in favor or “leaned” towards group selection. We are winning!


A major Indo-European contribution to the spread lactase persistence after all?

Ewen Callaway ("DNA data explosion lights up the Bronze Age: Population-scale studies suggest that migrants spread steppe language and technology."):
Ancient population genomics also offer insights on physical and physiological traits. Allentoft’s team found that the ability to digest milk into adulthood — nearly universal in northern Europeans today — was rare in Bronze Age Europeans, contradicting earlier claims that the trait helped early European farmers to gain calories from milk. Of the 101 sequenced individuals, the Yamnaya were most likely to have the DNA variation responsible for lactose tolerance, hinting that the steppe migrants might have eventually introduced the trait to Europe.
Related: More ancient DNA evidence of Indo-European mass migrations