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!:

https://twitter.com/History_Pics/status/644508143049940992
_____

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

linkfest – 03/05/14

DNA USA*“[A]bout about 4 percent of whites have at least 1 percent or more African ancestry. Although it is a relatively small percentage, the percentage indicates that an individual with at least 1 percent African ancestry had an African ancestor within the last six generations, or in the last 200 years. This data also suggests that individuals with mixed parentage at some point were absorbed into the white population. Looking a little more deeply into the data, Kasia also found that the percentage of whites with hidden African ancestry differed significantly from state-to-state. Southern states with the highest African American populations, tended to have the highest percentages of hidden African ancestry…. Previous published studies estimate that on average African Americans had about 82 percent African ancestry and about 18 percent European ancestry. But in self-identified African Americans in 23andMe’s database, Kasia found the average amount of African ancestry was closer to 73 percent. Kasia found significant differences in state-to-state comparisons. African Americans in the northern and western states have more mixed ancestry than those in the southern states…. On average Latinos had about 70 percent European ancestry, 14 percent Native American ancestry and 6 percent African ancestry. The remaining ancestry is difficult to assign because the DNA is either shared by a number of different populations around the world, or because it’s from understudied populations, such as Native Americans.” – from 23andMe.

Common Variants in the CDH7 Gene are Associated with Major Depressive Disorder in the Han Chinese Population“Recent genome-wide association study also demonstrated that CDH7 was significant associated with bipolar disorder…. Our results support CDH7 to be a risk factor of MDD in the Han Chinese population. However, further studies with more markers and independent samples were suggested to validate our findings.”

Humans May Have Been Stuck on Bering Strait for 10,000 Years“In the new Perspectives article, published today (Feb. 27) in the journal Science, the researchers compile existing data to support the idea, known as the Beringia standstill hypothesis. Among that evidence is genetic data showing that founding populations of Native Americans diverged from their Asian ancestors more than 25,000 years ago. In addition, land in the region of the Bering Strait teemed with grasses to support big game (for food) and woody shrubs to burn in the cold climate, supporting a hard-scrabble existence for ancient people.” – razib is skeptical.

Was skin cancer a selective force for black pigmentation in early hominin evolution?“[D]ata on age-associated cancer incidence and lethality in albinos living at low latitudes in both Africa and Central America support the contention that skin cancer could have provided a potent selective force for the emergence of black skin in early hominins.”

Neanderthal Introgression at Chromosome 3p21.31 Was Under Positive Natural Selection in East Asians“Studies of the Neanderthal and Denisovan genomes demonstrate archaic hominin introgression in Eurasians. Here, we present evidence of Neanderthal introgression within the chromosome 3p21.31 region, occurring with a high frequency in East Asians (ranging from 49.4% to 66.5%) and at a low frequency in Europeans. We also detected a signal of strong positive selection in this region only in East Asians…. [S]uggestive evidence supports latitude-dependent selection, implicating a role of ultraviolet-B.”

Neanderthals challenge the origins of speech“Neanderthals, may well have spoken in languages not dissimilar to the ones we use today…. [I]n terms of mechanical behaviour, the Neanderthal hyoid was basically indistinguishable from our own, strongly suggesting that this key part of the vocal tract was used in the same way. ‘From this research, we can conclude that it’s likely that the origins of speech and language are far, far older than once thought.'” – h/t billare (who is 0.1% neanderthal)!

READ THIS (yes, there *will* be a pop quiz on the material later in the week (~_^) )!: Environmental Hereditarianism“[T]here is little evidence linking most ‘measurable’ aspects of the environment to human physical or behavioral traits…. Most of the solid evidence we do have for environmental impacts come in the forms of things that do physical damage (e.g., maiming limbs or traumatic brain injury) – a category which includes poisons; or are developmental deficits, such as malnutrition. Much of the rest of it (take your pick) is lacking.” – from jayman. – previously: it’s not nature and nurture….

Outliers – from greg cochran.

New evidence confirms link between IQ, brain cortex“Rate of change in the thickness of the brain’s cortex is an important factor associated with a person’s change in IQ, according to a collaborative study by scientists in five countries…. This study is the first to show the association between cortical thickness and development in full scale IQ, and has potentially wide-ranging implications for the pedagogical world and for judicial cases in which the defendant’s IQ score could play a role in determining the severity of the sentence.”

The Germ Theory of Democracy, Dictatorship, and All Your Most Cherished Beliefs“What kind of government do you live under? Who are your sexual partners? How do you treat strangers? All of these questions may mask a more fundamental one: What germs are you warding off?” – h/t jason collins! – but see this previous post: pathogens and consanguinity“the BIG outliers, though, are the arabs and all their middle eastern/north african/south asian muslim buddies. they are the ones throwing off the correlation completely…. these societies are amongst those that have the highest consanguinity rates, and yet some of their pathogen index scores are *very* low.” that part of the world also does not do well when it comes to (liberal) democracy. – see also jayman’s response.

Nicholas Wade Takes on the Regime – jared taylor reviews nicholas wade’s upcoming book on race. – h/t hbd bibliography! – see also this comment from jayman. – and see also Harmful, toxic equalism from the awesome epigone.

The Nature of Race – from karl boetel and john furest. see also here.

12,000 year old prehistoric art shows woman hunting – maybe. kinda/sorta. (not really.) – from adam benton.

Altruism and the Dark Side of Agreeableness“[B]eware of really nice people. If they seem too good to be true, they usually are.” – from staffan.

Forgotten fathers: paternal influences on mammalian sex allocation“A growing body of evidence suggests that the assumption that males produce an unbiased proportion of X- and Y-chromosome-bearing spermatozoa is not always valid with significant between- and even within-individual variation.” – a mechanism for trivers-willard? – h/t lars penke!

Digit Span: the modest little bombshell and What does IQ 70 mean for black and white kids? – from dr. thompson.

The paradox of the Visual Word Form Area“The VWFA functions differently in different human populations. The difference is striking between people who use alphabetical script, where each symbol represents a sound, and those who use logographic script, where each symbol represents an idea. Chinese subjects process their idea-based symbols with assistance from other brain regions, whereas Westerners process their sound-based symbols only in the VWFA.” – from peter frost.

The man who destroyed America’s ego“How a rebel psychologist challenged one of the 20th century’s biggest—and most dangerous—ideas…. Among the most egregious errors they discovered were those in the papers that focused on academic performance. A correlation had been repeatedly found between high self-esteem and good grades. So, the logic went, if you boosted self-esteem you’d also boost grades. But the authors had made one of the most elementary mistakes in science. ‘When they tracked people over time,’ says Baumeister, ‘the grades came first, and then the self-esteem. High self-esteem was a *result* of good grades, not a cause.'” – h/t matthew wygant!

Genetic Influences on Political Ideologies: Twin Analyses of 19 Measures of Political Ideologies from Five Democracies and Genome-Wide Findings from Three Populations“Here we present results from original analyses of a combined sample of over 12,000 twins pairs, ascertained from nine different studies conducted in five democracies, sampled over the course of four decades. We provide evidence that genetic factors play a role in the formation of political ideology, regardless of how ideology is measured, the era, or the population sampled…. We then present results from one of the first genome-wide association studies on political ideology using data from three samples: a 1990 Australian sample involving 6,894 individuals from 3,516 families; a 2008 Australian sample of 1,160 related individuals from 635 families and a 2010 Swedish sample involving 3,334 individuals from 2,607 families. No polymorphisms reached genome-wide significance in the meta-analysis. The combined evidence suggests that political ideology constitutes a fundamental aspect of one’s genetically informed psychological disposition, but as Fisher proposed long ago, genetic influences on complex traits will be composed of thousands of markers of very small effects and it will require extremely large samples to have enough power in order to identify specific polymorphisms related to complex social traits.”

Why Americans Are So Polarized: Education and Evolution“Improvements in learning — which correlates with stronger partisanship — and the tendency to choose likeminded mates may be helping to create divided politics.” – from avi tuschman. – h/t eddy elmer!

Conservatives generally more willing to take business risks, study finds

Paternal Age at Childbearing and Offspring Psychiatric and Academic Morbidity“In the study population, advancing paternal age was associated with increased risk of some psychiatric disorders (eg, autism, psychosis, and bipolar disorders) but decreased risk of the other indexes of morbidity.”

A Genotype-First Approach to Defining the Subtypes of a Complex Disease – h/t kevin mitchell who tweeted: “Increasing recog’n that ‘common disorders; like autism really umbrella terms for many rare diseases.”

Researchers look at boy-girl differences in autism“Boys, it seems, can develop autism from a relatively small genetic hit, according to a study published today in the American Journal of Human Genetics. It takes more of a genetic wallop, though, to cause autism in girls – so when they do get it, they’re worse off. The same explanation holds true, researchers think, for the gender imbalance in ADHD (attention-deficit hyperactivity disorder), intellectual disabilities and schizophrenia.” – see also: A Higher Mutational Burden in Females Supports a “Female Protective Model” in Neurodevelopmental Disorders.

China Cracks Down on DNA Testing – h/t jayman!

Epigenetics: The sins of the father – big story in nature today. – “The roots of inheritance may extend beyond the genome, but the mechanisms remain a puzzle.” – but swedish scientist on twitter says: “But Rando misquotes Swedish human data in his Cell paper on mice. Caution for epigenetic hype!” – hmmmm. =/

The Consequences of Natural Morality“Good and Evil are not objective things. They exist as subjective impressions, creating a powerful illusion that they are objective things. This illusion that Good and Evil are objects independent of the conscious minds that imagine them exists for a good reason. It ‘works.’ In other words, its existence has enhanced the probability that the genes responsible for its existence will survive and reproduce.” – from helian.

Digit ratio predicts eminence of Polish actors – this one’s for sisyphean! (^_^) – h/t ben southwood!

Sex differences in color preferences transcend extreme differences in culture and ecology.

In Academia, Women Collaborate Less With Their Same-Sex Juniors“‘Some older women treated us younger women almost worse than some men did,’ she says. ‘We called it the “Queen Bee syndrome.”‘” – heh. – h/t claire lehmann!

Women Can Keep the Vote: No Evidence That Hormonal Changes During the Menstrual Cycle Impact Political and Religious Beliefs – behind paywall.

Women ‘subconsciously outdo other females’ during ovulation“But what the researchers found really surprising is that ovulating women did not appear to want a higher standing over men – they became kinder to them. When playing the dictator game, non-ovulating women shared 45% of their money with men, while ovulating women were willing to share 60% of their money with men. These findings are unlike anything we have ever seen in the dictator game. You just don’t see people giving away more than half of their money,’ says Prof. Durante.” – (~_^)

Women Outperform Men in Ultra-Distance Swimming – The ‘Manhattan Island Marathon Swim’ From 1983 to 2013. – because we float better (because we have that extra layer of fat)? (~_^)

Sameness and the self: philosophical and psychological considerations.“[H]ow can a person maintain a belief in the sameness of self over time in the face of continual psychological and physical change?” – h/t neuroskeptic!

Young Children Can Be Taught Basic Natural Selection Using a Picture-Storybook Intervention – but not politically correct people, apparently. (~_^) – h/t stuart ritchie!

Study: Racial bias in pain perception appears among children as young as 7 – see also: Psychologists use baby-cam to study infants’ exposure to faces.

Mixed-race children ‘are being failed’ in treatment of mental health problems“Children of mixed race are at greater risk of suffering from mental health problems and are not getting the support they need, says a report.” – in the u.k.

Inferring Character From Faces: A Developmental Study.“This research suggests that the predisposition to judge others using scant facial information appears in adultlike forms early in childhood and does not require prolonged social experience.”

Los europeos no inventaron la desigualdad en Hispanoamérica – from eduardo zugasti.

Native American city on the Mississippi was America’s first ‘melting pot’carcosa cahokia. – “By analyzing the teeth of those buried in different locations in Cahokia, Emerson, state archaeological survey bioarchaeologist Kristin Hedman and graduate student Philip Slater discovered that immigrants formed one-third of the population of the city throughout its history (from about AD 1050 through the early 1300s).”

Two-hundred-year drought doomed Indus Valley Civilization“Monsoon hiatus that began 4,200 years ago parallels dry spell that led civilizations to collapse in other regions.”

HBD 101 – from malcolm pollack. (*^_^*)

bonus: A ‘Second Great Wave’ of immigration?“‘Once again, the country is approaching a percentage of foreign-born not seen since the late 1800s and early 1900s,’ the Census Bureau wrote on its blog this week.” – =/ – h/t ray sawhill!

bonus bonus: Muhammad’s birthplace to be razed – remember that the najdis hate the hejazis and vice versa.

bonus bonus bonus: Giant Virus, Awakened From 30,000-Year Slumber, Is Still Infectious – ruh roh (if you’re an amoeba)!

bonus bonus bonus bonus: Crawling Through The Brain Without Getting Lost“Do the wasps taste their way through a cockroach brain?” – mmmmmm! =/

bonus bonus bonus bonus bonus: Australia: Snake eats crocodile after battle – WITH PICTURES! =o – h/t ed west!

(note: comments do not require an email. g-8 selfie. (~_^) )