linkfest – 09/20/15

What Your DNA Says About Medieval History“A new study uses genetic data from living people to trace millennia-old migration patterns…. [M]uch of what Capelli and his colleagues discovered meshed with what historians already knew. For example, among northern Europeans, highest rate of admixing took place ‘around the late first millennium C.E., a time known to have involved significant upheaval in Europe,’ while admixture between north African and southern European populations was dated to a time span ‘consistent with migrations associated with the Arabic Conquest of the Iberian peninsula.’ But there were surprises, too. Most notably, Capelli and his colleagues discovered evidence for an influx of Mongolians into Europe that predated the reign of Ghengis Khan.” – orig. research article: The Role of Recent Admixture in Forming the Contemporary West Eurasian Genomic Landscape.

Inuit Study Adds Twist to Omega-3 Fatty Acids’ Health Story“A study published on Thursday in the journal Science reported that the ancestors of the Inuit evolved unique genetic adaptations for metabolizing omega-3s and other fatty acids. Those gene variants had drastic effects on Inuit’s bodies, reducing their heights and weights. Rasmus Nielsen, a geneticist at the University of California, Berkeley, and an author of the new study, said that the discovery raised questions about whether omega-3 fats really were protective for everyone, despite decades of health advice. ‘The same diet may have different effects on different people,’ he said…. The researchers found several genetic variants at different locations in the genome that were unusually common in the Inuit, compared with people in Europe or China. Several of these variations occurred within a cluster of genes that direct construction of enzymes called fatty acid desaturases. (The genes are called FADS, for short….) Even more intriguing was the fact that one of these gene variants was present in almost every Inuit in the study. It is much less common in other populations: About a quarter of Chinese people have it, compared with just 2 percent of Europeans. Natural selection is the only known way this gene variant could have become so common in the Inuit. Dr. Nielsen said this adaptation might have arisen as long ago as 20,000 years, when the ancestors of the Inuit were living in the Beringia region, which straddles Alaska and Siberia…. The adaptation did more than just change blood levels of fatty acids, the scientists found. Inuit who carried two copies of the variant gene were on average an inch shorter and 10 pounds lighter than those without a copy.” – orig. research article: Greenlandic Inuit show genetic signatures of diet and climate adaptation. see also Your Genes Are What You Eat from razib.

Height-reducing variants and selection for short stature in Sardinia“[K]nown height-decreasing alleles are at systematically higher frequencies in Sardinians than would be expected by genetic drift. The findings are consistent with selection for shorter stature in Sardinia and a suggestive human example of the proposed ‘island effect’ reducing the size of large mammals.” – h/t andrew sabisky!

Are humans still evolving? Yes, both globally and locally. – from jerry coyne.

5 key facts about the nuclear DNA from Sima de los Huesos“If confirmed, the results will push back the H. sapiens-H. neanderthalensis ancestor beyond 400 KYA. Meyer suggested that the ancestors of H. sapiens could have diverged from the branch leading to neandertals and denisovans 550 K to 765 K years ago. It may be possible that H. sapiens evolved in western Eurasia and later migrated back into Africa. The fossils from Europe, Asia and Africa in the 400 Ka. period are physically very diverse and may represent multiple species, only one of which could be the ancestor of today’s humans. For example, Chris Stringer thinks it may be needed to look at Homo antecessor and not Homo heidelbergensis as our last common ancestor with neandertals.”

New DNA tests on ancient Denisovan people ‘shows them occupying Altai cave 170,000 years ago’“Prehistoric Siberians lived in Denisova Cave earlier than scientists realised – new claim based on state-of-the-art technology.” – h/t paleoanthropology!

Origins, admixture and founder lineages in European Roma“We found a set of founder lineages, present in the Roma and virtually absent in the non-Roma, for the maternal (H7, J1b3, J1c1, M18, M35b, M5a1, U3, and X2d) and paternal (I-P259, J-M92, and J-M67) genomes. This lineage classification allows us to identify extensive gene flow from non-Roma to Roma groups, whereas the opposite pattern, although not negligible, is substantially lower (up to 6.3%). Finally, the exact haplotype matching analysis of both uniparental lineages consistently points to a Northwestern origin of the proto-Roma population within the Indian subcontinent.”

Why I’m sceptical about the idea of genetically inherited trauma“A recent scientific paper claiming that the children of Holocaust survivors showed evidence of inherited stress was deeply flawed – here’s why.”

Population genetic differentiation of height and body mass index across Europe“Here we find that many independent loci contribute to population genetic differences in height and body mass index (BMI) in 9,416 individuals across 14 European countries.”

North-South divide, Japanese style – from dr. james thompson.

Genetics of IQ and lifespan and Genius? Avoid rare functional genes and Heritability of Specific Cognitive Abilities and Schizophrenia and cognitive decline and g for Latinos and White matter efficiency predicts women’s IQ, but not men’s – all also from dr. james thompson!

SNP hits on cognitive ability from 300k individuals – from steve hsu. h/t holtz!

Do smart girls postpone first sex? and Do women find bright men sexy? – and even MORE from dr. james thompson!! whew!

Green Arabia’s key role in human evolution“Scientists have been illuminating the vital role played by the Arabian Peninsula in humankind’s exodus from Africa. Far from being a desert, the region was once covered by lush vegetation and criss-crossed by rivers, providing rich hunting grounds for our ancestors.”

The UK10K project identifies rare variants in health and disease – h/t kevin mitchell!

Genetics of aggressive behavior: An overview – h/t brian boutwell!

Sons of the Soil, Migrants, and Civil War“In nearly a third of ethnic civil wars since 1945, the conflict develops between members of a regional ethnic group that considers itself to be the indigenous “sons of the soil” and recent migrants from other parts of the country.” – h/t whyvert!

It’s finally out: The big review paper on the lack of political diversity in social psychology“Psychologists have demonstrated the value of diversity – particularly diversity of viewpoints – for enhancing creativity, discovery, and problem solving. But one key type of viewpoint diversity is lacking in academic psychology in general and social psychology in particular: political diversity.” – from jonathan haidt.

The genetics of alcohol dependence: Twin and SNP-based heritability, and genome-wide association study based on AUDIT scores – h/t amir sariaslan!

Chronotype Associations with Depression and Anxiety Disorders in a Large Cohort Study – h/t emily deans! who tweeted: “‘Morning people’ less likely to be depressed in this large and relatively thorough observational study.” – (morning people depress me. (~_^) )

The Hormone That Bonds Humans to Dogs – h/t old whig! who tweeted: “Evolutionary change is faster than we think? Case study: oxytocin.”

Does the Gender of Offspring Affect Parental Political Orientation? – h/t ben southwood! who tweeted: “Studies on offspring gender & political orientation plagued by publication bias; actually there’s no relationship.”

Do Angry Birds Make for Angry Children? A Meta-Analysis of Video Game Influences on Children’s and Adolescents’ Aggression, Mental Health, Prosocial Behavior, and Academic Performance“Overall, results from 101 studies suggest that video game influences on increased aggression (r = .06), reduced prosocial behavior (r = .04), reduced academic performance (r = −.01), depressive symptoms (r = .04), and attention deficit symptoms (r = .03) are minimal.” – h/t joseph schwartz!

Ancient campfires show early population numbers [in australia]“ANU archaeologist Alan Williams used radio carbon dating technology to examine charcoal dates from more than 1000 prehistoric campfires and based on this he says populations appear to have increased steadily until 25,000 years ago…. After this initial increase, he says, population levels remained steady or even declined from 25,000 years ago, during the more arid Last Glacial Maximum (25,000 to 13,000 years ago) when temperatures were about ten degrees cooler…. Campfire numbers began to grow again 13,000 years ago when the northern wet season re-emerged.”

Aboriginal ‘memories’ of Australia’s coastline go back more than 7,000 years

History became legend, legend became myth: Crater Lake – h/t razib! who tweeted: “8,000 year old explosion preserved in folk memory of klamath indians?”

Ancient Script Spurs Rethinking of Historic ‘Backwater’“At a temple site in the Republic of Georgia, letters carved in stone could change the way we see the development of writing.”

bonus: Microbiologists Keep Finding Giant Viruses in Melting Permafrost

bonus bonus: Ancient Cats Drove Ancient Dogs to Extinction – woof? (O.O)

bonus bonus bonus: this year’s ig nobel mathematics prize went to the authors of The Case of Moulay Ismael – Fact or Fancy?“Textbooks on evolutionary psychology and biology cite the case of the Sharifian Emperor of Morocco, Moulay Ismael the Bloodthirsty (1672–1727) who was supposed to have sired 888 children. This example for male reproduction has been challenged and led to a still unresolved discussion. The scientific debate is shaped by assumptions about reproductive constraints which cannot be tested directly — and the figures used are sometimes arbitrary. Therefore we developed a computer simulation which tests how many copulations per day were necessary to reach the reported reproductive outcome…. The results indicate that Moulay Ismael could have achieved this high reproductive success. A comparison of the three conception models highlights the necessity to consider female sexual habits when assessing fertility across the cycle. We also show that the harem size needed is far smaller than the reported numbers.” (~_^)

and the tweet of the week!:

(note: comments do not require an email. moulay ismael the bloodthirsty!)


linkfest – 09/28/14

Europeans drawn from three ancient “tribes”“The modern European gene pool was formed when three ancient populations mixed within the last 7,000 years, Nature journal reports. Blue-eyed, swarthy hunters mingled with brown-eyed, pale skinned farmers as the latter swept into Europe from the Near East. But another, mysterious population with Siberian affinities also contributed to the genetic landscape of the continent.” – see also: Before Slavery“From what I can see so far, it looks as the invaders killed all the LBK-descended farmers in northern Europe, or nearly so. The locals had had long trapezoidal houses clustered in small villages: the Corded Ware culture has almost no buildings at all, and a lot less agriculture. They didn’t make the EEF guys serfs and get a cut of their grain – the villages disappeared. They didn’t tax them, but then money and bureaucracy hadn’t been invented yet. Same for slavery: hadn’t been invented, probably. Judging from the mtDNA patterns, they didn’t even grab many of the nubile women. The genetic mix changes little as you move across the north European plain: if the invaders were picking up local genes as they rolled along, it should have. We used to call Corded Ware the Battle-Axe culture, but that’s too accurate for comfort.” – from greg cochran.

They weren’t wimps: how modern humans, like Neanderthals, braved the northern cold“Recent finds at Willendorf in Austria reveal that modern humans were living in cool steppe-like conditions some 43,500 years ago – and that their presence overlapped with that of Neanderthals for far longer than we thought.” – h/t mr. robert ford!

Stone Age groups made similar toolmaking breakthroughs“Different palaeolithic populations around the world might have developed a crucial toolmaking skill independently. This conclusion, based on the analysis of hundreds of artefacts from a recently excavated archaeological site in Armenia, weakens a long-held theory that Stone Age people in Eurasia learnt sophisticated techniques from migrating African tribes. The work is published in Science.”

Human paternal and maternal demographic histories: insights from high-resolution Y chromosome and mtDNA sequences“Comparisons of maternally-inherited mitochondrial DNA (mtDNA) and paternally-inherited non-recombining Y chromosome (NRY) variation have provided important insights into the impact of sex-biased processes (such as migration, residence pattern, and so on) on human genetic variation…. Our results confirm the controversial assertion that genetic differences between human populations on a global scale are bigger for the NRY than for mtDNA, although the differences are not as large as previously suggested. More importantly, we find substantial regional variation in patterns of mtDNA *versus* NRY variation.” – h/t juan fernández lópez! – see also: New analysis of human genetic history reveals female dominance – (heh. that was a nice twist on the story! (~_^) ) h/t frau katze!

23andMe mega-study on different American groups – @dienekes’. see also: The genetic ancestry of African, Latino, and European Americans across the United States.

Admixture in Latin America: Geographic Structure, Phenotypic Diversity and Self-Perception of Ancestry Based on 7,342 Individuals“We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú). These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry.” – see also razib: The Phenotypic and the Genotypic.

Ashkenazi Jewish population has distinctive, yet similar genomes“Post-population bottleneck, descendants of Eastern European Jews are all 30th-ish cousins…. Compared to genomes of modern Europeans—in this case, the genomes of 26 Flemish people—the Ashkenazi genomes have 47 percent more novel DNA differences per genome. These DNA variants, while novel, are population specific; sequence sharing, where two individuals have a set of the same variants, is eight percent more abundant among the Ashkenazi Jews than it is between the two populations or even among the Flemish genomes.” – h/t billare!

Why Did Civilization Lag in Africa? – from steve sailer.

Force of nature gave life its asymmetry“‘Left-handed’ electrons destroy certain organic molecules faster than their mirror versions.”

make sure not to miss jayman’s new Obesity Facts page. and give him some money, too! (^_^)

A fruitful encounter“Did the Christian doctrine of original sin create the guilt cultures of Northwest Europe? Or did the arrow of causality run the other way?” – from peter frost.

Review: G Is for Genes: The Impact of Genetics on Education and Achievement (Kathryn Asbury, Robert Plomin) – from emil kirkegaard.

The hereditarian hypothesis almost certainly true“Surely, there are huge benefits to being the first author to publish a study that almost conclusively disproves the genetic model for AA’s. Researchers with access to the data have a strong incitement to publish such a study. If the data supports the view, they have all the necessary means too. Since they haven’t published it, we can hence infer that the data does not support the politically favorable non-genetic conclusion, but instead the genetic model.” – also from emil kirkegaard.

Cognitive ability and party identity in the United States“[I]ndividuals who identify as Republican have slightly higher verbal intelligence than those who identify as Democrat…. [H]igher intelligence among classically liberal Republicans compensates for lower intelligence among socially conservative Republicans.” – the results suggest. – h/t stuart ritchie!

Lighter-skinned minorities are more likely to support Republicans

A study of the performance of Egyptian college students on the Advanced Progressive Matrices“The Egyptian raw scores were transformed to British IQ equivalents using the published 1992 British norms for the APM, on which the sample obtained a British IQ of 89.5. Science students obtained a significantly higher average mean score than arts students by 7.5 IQ points. Male students obtained a non-significantly higher average IQ than female students 1.2 IQ points. Male students had greater variability than the female students.” – h/t erwin schmidt!

The Available Pool – ed realist goes all voldemort on us. again.

Epigenetics, the Glory and the Hype“Epigenetics is real. But it doesn’t change everything. That needs to be said, because people seem to get the impression that everything is changed.” – from razib.

Human preferences for sexually dimorphic faces may be evolutionarily novel [pdf] – “A large literature proposes that preferences for exaggerated sex typicality in human faces (masculinity/femininity) reflect a long evolutionary history of sexual and social selection. This proposal implies that dimorphism was important to judgments of attractiveness and personality in ancestral environments. It is difficult to evaluate, however, because most available data come from large-scale, industrialized, urban populations. Here, we report the results for 12 populations with very diverse levels of economic development. Surprisingly, preferences for exaggerated sex-specific traits are only found in the novel, highly developed environments. Similarly, perceptions that masculine males look aggressive increase strongly with development and, specifically, urbanization.” – h/t jayman!

Do your genes skew how you taste alcohol?“A new study shows that how people perceive and taste alcohol varies as a result of genetics. The scientists focused on three chemosensory genes—two bitter-taste receptor genes known as TAS2R13 and TAS2R38 and a burn receptor gene, TRPV1. The research is the first to consider whether variation in the burn receptor gene might influence alcohol sensations, which has not previously been linked to alcohol consumption.” – alcohol tastes gooooood! (~_^) – h/t phillip melton!

Parent–Offspring Similarity for Drinking: A Longitudinal Adoption Study [pdf] – “Findings imply that genetic influences on drinking behavior increase with age while shared family environment influences decline, especially during the transition from late-adolescence to early adulthood.” – h/t emil kirkegaard!

Violent Video Games and Real-World Violence: Rhetoric Versus Data“Contrary to the claims that violent video games are linked to aggressive assaults and homicides, no evidence was found to suggest that this medium was positively related to real-world violence in the United States. Unexpectedly, many of the results were suggestive of a decrease in violent crime in response to violent video games. Possible explanations for these unforeseen findings are discussed and researchers are cautioned about generalizing the results from laboratory and correlational studies to severe forms of violent behavior.” – h/t mugwump! who tweeted some of the tables here, here, and here.

The Objective Morality Delusion“Atheists often scorn those who believe in the God Delusion. The faithful, in turn, scorn those atheists who believe in the Objective Morality Delusion. The scorn is understandable in both cases, but I give the nod to the faithful on this one….” – from helian.

Paradox of nationalism“Nationalism as we know it arose in modern times in Europe. Other countries outside Europe just don’t seem to have the same thing, although there are exceptions, such as Japan, or maybe Turkey. And in fact, nationalism was at one time considered a part of liberalism – which is another European invention…. Other countries that don’t have the same history as Europe seem unlikely to develop that kind of nationalism. Think of Iraq, Syria, most African countries, even China: they are more given to clannishness than patriotism.” – from mr. mangan, esq.

Plant breeding, not working slaves harder, drove cotton efficiency gains in the US South – from pseudoerasmus.

Confusion Over the Biological Reality of the Human Races“[O]ne can see clearly why Wade’s argument is not racist: at the core of his argument is his claim that the tribalism of racial ethnocentrism belongs to an ancient stage of human evolution that has to be overcome to move into modern states and inclusive institutions (see Wade, 136, 173-82, 196-97).” – larry arnhart on A Troublesome Inheritance.

Yes, it’s official, men are from Mars and women from Venus, and here’s the science to prove it“In his fascinating new book the developmental biologist Lewis Wolpert argues that there is actually hard science behind many of our stereotypical gender roles.” – h/t claire lehmann!

The Woman’s Heart Attack“[M]en more typically have ‘crushing’ pain; women, nausea. That women are likelier to have early warning signs, such as unaccustomed fatigue or insomnia (unaccustomed: That’s the key word here). That we are likelier — this spooked me and kept me, for months, glued to calendars — to die within a year of a heart attack. That our symptoms can be so varied and nuanced that we feel no fear, seek no help, and possibly die — which may be why, although more men have heart attacks, a greater percentage of women die of them.”

The Evolution of Culturally-Variable Sex Differences: Men and Women Are Not Always Different, but When They Are…It Appears *Not* to Result from Patriarchy or Sex Role Socialization“[E]vidence is marshaled across 21 data sources that directly challenge this foundational assumption of social role theory. Empirically, sex differences in most psychological traits — in personality, sexuality, attitudes, emotions, behaviors, and cognitive abilities — are conspicuously *larger* in cultures with more egalitarian sex role socialization and greater sociopolitical gender equity. Even sex differences in many physical traits such as height, obesity, and blood pressure are larger in cultures with more egalitarian sex role socialization and greater sociopolitical gender equity.”

School Performance After Preterm Birth“An increased risk of poor school performance for children born preterm has been shown in many studies, but whether this increase is attributable to preterm birth per se or to other factors associated with preterm birth has not been resolved…. Preterm birth was strongly and negatively correlated with school performance. The distribution of school grades for children born at 31-33 weeks was on average 3.85 (95% confidence interval = -4.36 to -3.35) centiles lower than for children born at 40 weeks. For births at 22-24 weeks, the corresponding figure was -23.15 (-30.32 to -15.97). When taking confounders into account, the association remained. When restricting the analysis to siblings, however, the association between school performance and preterm birth after week 30 vanished completely, whereas it remained, less pronounced, for preterm birth before 30 weeks of gestation. Our study suggests that the association between school performance and preterm birth after 30 gestational weeks is attributable to factors other than preterm birth per se.”

Are Neighborhood Health Associations Causal? A 10-Year Prospective Cohort Study With Repeated Measurements – h/t amir sariaslan! who tweeted: “Neighborhoods did not cause health outcomes in Australian large longitudinal within-individual study over 10 years.”

Seat of Selflessness Found in Brains of Extreme Altruists“In this case researchers chose to study people who donated a kidney to a complete stranger. They found that not only are extreme altruists’ brains different from a normal person’s, they’re basically the opposite of a psychopath’s in one key way – indicating that a specific brain region may play an important role in people’s ability to care for one another.” – n=39, but it’s a start!

Can the Game of Thrones option save the UK?“The situation now resembles the Union of Crowns from 1603-1707 when Scotland had its own parliament but was still under the king in Westminster, and Cameron is behaving like Charles I: making promises to his northern kingdom that affect the southern one, without regards to how the southerners feel. Just as in 1640, the greatest protests are coming from the east of England, once the stronghold of Puritanism and the parliamentary rebels and now the Ukip heartland.” – from ed west.

God, Darwin and My College Biology Class“[A] third consequence of evolutionary insights: a powerful critique of theodicy, the scholarly effort to reconcile belief in an omnipresent, omni-benevolent God with the fact of unmerited suffering. Theological answers range from claiming that suffering provides the option of free will to announcing (as in the Book of Job) that God is so great and we so insignificant that we have no right to ask. But just a smidgen of biological insight makes it clear that, although the natural world can be marvelous, it is also filled with ethical horrors: predation, parasitism, fratricide, infanticide, disease, pain, old age and death — and that suffering (like joy) is built into the nature of things. The more we know of evolution, the more unavoidable is the conclusion that living things, including human beings, are produced by a natural, totally amoral process, with no indication of a benevolent, controlling creator.” – david barash, pessimist(?).

Incest a “fundamental right” says German committee says“Anti-incest laws in Germany could be scrapped after a government-backed group said relationships between brothers and sisters should be legal.” – those wacky germans! h/t anatoly!

Radicalised Muslims in UK more likely to be born in Britain, rich and depressed“Young British Muslims whose families have lived in the UK for generations are more at risk of radicalisation than recent migrants to Britain, according to new research which reveals the common characteristics of those most vulnerable to recruitment by terrorists.” – we’ve seen that pattern before. h/t ed west!

Millions of Old Tyres are Dumped Near Empty Apartment Blocks in Spanish Ghost Town – you HAVE to see the photos! h/t ian geldard!

bonus: Skin coloring of rhesus macaque monkeys linked to breeding success, new study shows

bonus bonus: Fantastically Wrong: Europe’s Insane History of Putting Animals on Trial and Executing Them – h/t kyle hill!

bonus bonus bonus: Belgium to build beer pipeline under Bruges – those wacky belgians!

(note: comments do not require an email. guilty!)