Archives for posts with tag: epigenetics is not magic

so the mother of all meta-analyses of twin studies and the heritability of human traits was published the other day: “Meta-analysis of the heritability of human traits based on fifty years of twin studies” [pdf].

the authors looked at “17,804 traits from 2,748 publications including 14,558,903 partly dependent twin pairs, virtually all published twin studies of complex traits.” 14.5+ MILLION twin pairs! as james thompson said, this study pretty much represents “the mother of ‘F*** Off’ samples.” (~_^) in future, if someone says to you that twin studies were debunked a long time ago, blah, blah, blah, just point them to this paper.

and the upshot is: we are not blank slates. we never were.

from the paper, “[A]cross all traits the reported heritability is 49%.” in other words, these researchers found that pretty much half of the variance in all sorts of physical and behavioral traits in humans — the differences that we see between people — can be accounted for by genetics.

here’s a key table from the paper. i took the liberty of jiggling it around a bit so it would fit better on the blog (h2 is what you should be looking at here — that’s narrow sense heritabilty):

twin studies meta-analysis

the press has picked this up as there being an even split between nature and nurture, genes versus “the environment.” here, for example, from the huffington post*:

“Nature Or Nurture? The Long-Running Debate May Finally Be Settled”

“It’s an age-old debate: do our genes make us who we are, or is it the environment in which we were raised?

“There’s long been agreement that both ‘nature’ and ‘nurture’ play some role in determining many aspects of our physical and mental selves, from our height and weight to our intelligence and disposition. But as to which plays the bigger role in shaping us, scientists have never seemed to agree.

“That debate may now be over, thanks to a sweeping analysis of studies conducted around the world for more than five decades. The analysis — involving more than 14.5 million twin pairs from 39 countries — indicates that nature and nurture are virtually tied.

“Across all of our traits, in other words, genes and environment exert equal influence.”

yeeeessss…but what is “the environment”? on hearing that most people will think of things like reading bedtime stories to kids or playing mozart to your unborn fetus. but those sorts of things are decidedly not what the environment is in this context. from kevin mitchell of wiring the brain:

i’ve blogged this before, but i think we all need to read it again — from steven pinker on “the environment”:

“Even the technical sense of ‘environment’ used in quantitative behavioral genetics is perversely confusing. Now, there is nothing wrong with partitioning phenotypic variance into components that correlate with genetic variation (heritability) and with variation among families (‘shared environment’). The problem comes from the so-called ‘nonshared’ or ‘unique environmental influences.’ This consists of all the variance that is attributable neither to genetic nor familiar variation. In most studies, it’s calculated as 1 – (heritability + shared environment). Practically, you can think of it as the differences between identical twins who grow up in the same home. They share their genes, parents, older and younger siblings, home, school, peers, and neighborhood. So what could make them different? Under the assumption that behavior is a product of genes plus environment, it must be something in the environment of one that is not in the environment of the other.

But this category really should be called ‘miscellaneous/unknown,’ because it has nothing necessarily to do with any measurable aspect of the environment, such as one sibling getting the top bunk bed and the other the bottom, or a parent unpredictably favoring one child, or one sibling getting chased by a dog, coming down with a virus, or being favored by a teacher. These influences are purely conjectural, and studies looking for them have failed to find them. The alternative is that this component actually consists of the effects of chance – new mutations, quirky prenatal effects, noise in brain development, and events in life with unpredictable effects.

“Stochastic effects in development are increasingly being recognized by epidemiologists, frustrated by such recalcitrant phenomena such as nonagenarian pack-a-day smokers and identical twins discordant for schizophrenia, homosexuality, and disease outcomes. They are increasingly forced to acknowledge that God plays dice with our traits. Developmental biologists have come to similar conclusions. The bad habit of assuming that anything not classically genetic must be ‘environmental’ has blinkered behavioral geneticists (and those who interpret their findings) into the fool’s errand of looking for environmental effects for what may be randomness in developmental processes.”

and more from kevin mitchell:

“Just because some trait is not genetic does not mean it is not innate. If we are talking about how the brain gets wired, any number of prenatal environmental factors are known to have large effects. More interestingly, however, and probably a greater source of variance across the population, is intrinsic developmental variation. Wiring the brain is a highly complex procedure, reliant on cellular processes that are, in engineering terms, inherently ‘noisy’. Running the programme from the same starting point (a specific genotype) does not generate exactly the same output (the phenotype) every time. The effects of this noise are readily apparent at the anatomical level, when examining the impact of specific mutations, for example. In many cases, the phenotypic consequences are quite variable between genetically identical organisms, or even on two sides of the same brain. (If you want to see direct evidence of such developmental variation, take a directly face-on photograph of yourself, cut it in half and make mirror-image copies of the left and right sides. You will be amazed how different the two resultant faces are).

If the way the brain is wired is determined, not just by the starting genotype, but, to a large extent by chance events during development, then it is reasonable to expect this variation to be manifest in many psychological traits. Such traits may thus be far more innate than behavioural genetics studies alone would suggest.

in other words, it’s NOT genes + environment (or nature + nurture) — not as most people would think of it anyway. it’s genes + shared environment (which, since it’s shared, i.e. the same for the individuals in question, oughtn’t to make a difference, right?) + nonshared environment (which can include de novo mutations and development noise, which also may be heritable! iow, variation itself might be a genetic trait.). not much room for the effects of nurture here.

so, when you see a figure like 51% for “environmental” causes behind the differences we see in traits between people, remember that that very much includes biological causes like new mutations that are particular to individuals and developmental “noise,” which again may ultimately be regulated by genes.

(and, no, it’s not epigenetics either! see here and here and here.)

h/t once again to jayman for cluing me in on this in the first place! (^_^)

*to give credit where credit is due, the huff post journalist did mention that part of what’s included in “the environment” is measurement error. that is correct. edit: see comment below about measurement error. so the 49% heritabilty figure should be considered a very conservative figure.

p.s. – there’s even a dedicated website where you can have a look at all the heritability numbers for yourself. enjoy!

see also: Gone with the Wind from dr. james thompson, Nature, nurture and noise from kevin mitchell, and About Developmental Noise and Environmental Hereditarianism from jayman.

previously: it’s not nature and nurture…

(note: comments do not require an email. the blank slate.)

Zigzags on a Shell From Java Are the Oldest Human Engravings“The early human Homo erectus also made the oldest known shell tools half a million years ago.” — see also: The art of Homo erectus“What we can say is that these artifacts carry information about the capabilities of their makers. The few non-perishable marked objects also speak to the likely presence of design in perishable elements of material culture. Clothing, however rudimentary, was likely to have been decorated in some way. Wooden tools were also probably notched and zigzagged — as the occasional bone and ivory implements suggest. They lived for the first time in a world that they could change.” – from john hawks.

Genetic diversity of Sub-Saharan Africa revealed[T]he researchers also found that there were more genetic similarities across Africa than they had thought. Dr Sandhu said: ‘The diversity among populations is not as diverse as we expected it to be….’ The researchers found that many Africans have some Eurasian DNA within their genetic ancestry, which suggests that Eurasians migrated back into Africa many thousands of years after they first left. And several of the populations were descended from the Bantu, a group that spread across Africa about 5,000 years ago.” — see also: The African Genome Variation Project shapes medical genetics in Africa.

and here is dienekes on the above study: African Genome Variation project paper“In too many papers to count, decreasing genetic diversity from East Africa was taken as evidence of an origin of H. sapiens in that locality and its expansion from there to Eurasia. This ‘East Africa=cradle of mankind’ theory has, as far as I can tell, nothing really to stand on. Granted, the oldest anatomically modern human remains have been found in East Africa 200-150 thousand years ago. But, the fact that old sapiens have been found in East Africa and not elsewhere is easily explained by the excellent conditions for preservation (as opposed, e.g., deserts or rainforests of Africa or elsewhere), and by the extraordinary effort by palaeoanthropologists in that area. One also needs to overlook a century of physical anthropology that concluded that East Africa was a contact zone between Caucasoids and Sub-Saharan Africans. We now know that there is no deep lineage of humans in modern east Africans. Take out the Eurasian ancestry and only a paltry Fst=0.027 remains with other Sub-Saharan Africans, a fraction of the Fst between, say, Europeans and East Asians.”

Living African group discovered to be the most populous humans over the last 150,000 years“New genetic research reveals that a small group of hunter-gatherers now living in Southern Africa once was so large that it comprised the majority of living humans during most of the past 150,000 years. Only during the last 22,000 years have the other African ethnicities, including the ones giving rise to Europeans and Asians, become vastly most numerous…. ‘This and previous studies show that the Khoisan peoples and the rest of modern humanity shared their most recent common ancestor approximately 150,000 years ago, so it was entirely unexpected to find that this group apparently did not intermarry with non-Khoisan neighbors for many thousand years….'” — see also The Least Bottlenecked Humans of All from razib.

Ants, altruism and self sacrifice“It’s the selfishness of genes that makes us unselfish…. ‘Group selection’ has always been portrayed as a more politically correct idea, implying that there is an evolutionary tendency to general altruism in people. Gene selection has generally seemed to be more of a right-wing idea, in which individuals are at the mercy of the harsh calculus of the genes. Actually, this folk understanding is about as misleading as it can be. Society is not built on one-sided altruism but on mutually beneficial co-operation. Nearly all the kind things people do in the world are done in the name of enlightened self-interest. Think of the people who sold you coffee, drove your train, even wrote your newspaper today. They were paid to do so but they did things for you (and you for them). Likewise, gene selection clearly drives the evolution of a co-operative instinct in the human breast, and not just towards close kin.” – from matt ridley. — see also: E.O. Wilson’s The Social Conquest of Earth from jason collins. h/t billare!

Genetic Variation in Human DNA Replication Timing“Replication timing, a driver of locus-specific mutation rates, varies among humans…. Replication timing associates with common polymorphisms near replication origins….” – whoa.

Genetic and environmental exposures constrain epigenetic drift over the human life course – h/t casey brown! who tweeted: “Worth repeating: DNA methylation is more genetic than epigenetic.”

IQ is in the genes“How parents raise us has no impact on how smart we become, a new study finds.”

Link discovered between fathers’ criminal history and sons’ intelligence“Sons whose fathers have criminal records tend to have lower cognitive abilities than sons whose fathers have no criminal history, data from over 1 million Swedish men show. The research, conducted by scientists in Sweden and Finland, indicates that the link is not directly caused by fathers’ behavior but is instead explained by genetic factors that are shared by father and son.”

Are bright people normal?“‘We found no support for the genetic Discontinuity Hypothesis that nonadditive genetic variance is greater for high intelligence….'” – from dr. james thompson.

Booze culture may date back 10 million years say scientists“A new study suggests that primates may have begun drinking alchol 10 million years ago, as fermented fruit on the forest floor…. Experts at Santa Fe College in the US studied the gene ADH4 which produces an enzyme to break down alcohol in the body. It was hypothesised that the enzyme would not appear until the first alcohol was produced by early farmers. But scientists were amazed to find it 10 million years earlier, at the end of the Miocene epoch.” – (them’s *my* ancestors right there! (~_^) )

Psychiatry: End of the Road for “Endophenotypes”?“In a nutshell, the researchers ran seven different genetic studies to try to find the genetic basis of a total of seventeen neurobehavioural traits, also known as ‘endophenotypes’…. Essentially an endophenotype is some trait, which could be almost anything, which is supposed to be related to (or part of) a psychiatric disorder or symptom, but which is ‘closer to genetics’ or ‘more biologica’ than the disorder itself. Rather than thousands of genes all mixed together to determine the risk of a psychiatric disorder, each endophenotype might be controlled by only a handful of genes – which would thus be easier to find…. Over 89% of the searches came up null in this way; for eight of the seventeen traits, the researchers found no associated genes using *any* strategy.” – from neuroskeptic.

Unequal fates for maths superstars“The fates of US child prodigies of the 1970s reveal great accomplishments but strong gender differences…. [B]oth genders reported unusually high levels of satisfaction with their lives and careers. ‘It seems that both sexes got what they wanted from life, even if those things were somewhat different….'” – h/t charles! – see also: Sometimes men and women want different things from ben southwood.

Are Chinese babies more docile? – peter frost on the freedman studies.

Inferior Faunas – from greg cochran.

Transparency International’s Corruption Perceptions Index 2014 released this week.

Domestication and Human Evolution Symposium @getCARTA sessions now available to watch online.

Does evolution need a revolution? – from jerry coyne.

Experimentally induced innovations lead to persistent culture via conformity in wild birds – birds have culture.

A Magisterial Synthesis Of Apes And Human Evolution“[Russell H.] Tuttle’s tome is a grand synthesis of all the latest research and data about apes and their relation to us…. He believes that bipedalism preceded the development of the brain in early humans –and was likely something inherited from smaller apes already used to using their feet to move laterally along branches in trees. Although chimpanzees and bonobos are our closest relatives on the evolutionary tree, they do not represent in their own locomotion good proto-models of what led to human upright posture and walking.”

‘Superbugs’ Kill India’s Babies and Pose an Overseas Threat“A growing chorus of researchers say the evidence is now overwhelming that a significant share of the bacteria present in India — in its water, sewage, animals, soil and even its mothers — are immune to nearly all antibiotics.” – h/t razib!

The RNA World: molecular cooperation at the origins of life“The RNA World concept posits that there was a period of time in primitive Earth’s history — about 4 billion years ago — when the primary living substance was RNA or something chemically similar. In the past 50 years, this idea has gone from speculation to a prevailing idea. In this Review, we summarize the key logic behind the RNA World and describe some of the most important recent advances that have been made to support and expand this logic. We also discuss the ways in which molecular cooperation involving RNAs would facilitate the emergence and early evolution of life.”

Tool to edit DNA revolutionizing research in Boston area – CRISPR.

Thomas Docherty on academic freedom“Managerial fundamentalism has taken hold in universities, with scholars viewed as resources that must be controlled…. A creeping incremental assault on academic freedom threatens not just what can be spoken aloud, but also what it is permissible to think: thought itself is to be subjected to management, so that its critical power is neutered or constrained….”

The Dark Enlightenment for Newbies“So what is dark about the Dark Enlightenment? Absolutely nothing. The Dark Enlightenment only looks dark in contrast to the blinding (as in, it blinds you) optimism of flash in the pan of blank slate equalism. The things that the DE contend about human nature — that parents naturally favor their children, that sexual attraction is a biological phenomenon, that some people are naturally smarter than others — were all accepted as common sense for most or all of human history. It is the unrealistic utopianism of modern liberalism which is ridiculously absurd. The Dark Enlightenment might be better termed The Return to Normalcy. So the phrase “Dark Enlightenment” might not be the best, but it has received enough attention that I don’t think we should abandon it.” – very nice post from empedocles.

Tanzania evicting 40,000 people from homeland to make room for Dubai royal family“It will become a private hunting reserve” – =/ (i’m linking to salon!) – h/t john durant!

bonus: Why Some Mosquitoes Spread Malaria and Others Don’t“Sequencing the genomes of numerous Anopheles mosquito species from locations around the world has shown why some can carry and spread the deadly disease malaria while others don’t.” – h/t srikant mantri!

bonus bonus: Humpback Whales in the Arabian Sea Have Been Isolated for 70,000 Years

bonus bonus bonus: A diet to die for“One bird feasts on food that would leave most other animals stone dead.”

bonus bonus bonus bonus: Insect Swarms Go Critical“Scientists have found tantalizing evidence that diverse biological systems, including the human brain, gene expression networks, bird flocks, and fish schools, behave as though they are near the ‘critical point’ of a phase transition, like correlated spins in a magnet on the verge of ordering.” – h/t jayman!

bonus bonus bonus bonus bonus: Weird Physics Can Make an Invisible Cat Visible“These cat pictures are brought to you by quantum entanglement as discussed by Einstein and Schrödinger.”

bonus bonus bonus bonus bonus bonus: “The Feynman Lectures on Physics”, The Most Popular Physics Book Ever Written, Now Completely Online

bonus bonus bonus bonus bonus bonus bonus: Tette per la Scienza – boobies! (it really IS this time! (~_^) )

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

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!)

“every society selects for something.”




see also: Talking to Economists

(note: comments do not require an email. epic genetics! (~_^) )

Skull Fossil Suggests Simpler Human Lineage“Early, diverse fossils — those currently recognized as coming from distinct species like Homo habilis, Homo erectus and others — may actually represent variation among members of a single, evolving lineage. In other words, just as people look different from one another today, so did early hominids look different from one another, and the dissimilarity of the bones they left behind may have fooled scientists into thinking they came from different species.” see also: Skull of Homo erectus throws story of human evolution into disarray @the guardian. see also john hawks: The new skull from Dmanisi. and greg cochran: All One Species?

speaking of species: Roe Deer × Domestic Sheep“This rather distant cross, which represents a case of interbreeding between separate mammalian families (Cervidae × Bovidae) was reported in the last decade of the 18th century by the Finnish academic Carl Niklas Hellenius (1745-1820), also known as Carl Niklas von Hellens (or af Hellens).” – say what?!

Mysterious Ancient Human Crossed Wallace’s Line“Scientists have proposed that the most recently discovered ancient human relatives — the Denisovans – somehow managed to cross one of the world’s most prominent marine barriers in Indonesia, and later interbred with modern humans moving through the area on the way to Australia and New Guinea.”

Blood-filled mosquito is a fossil first – JURASSIC PARK!!

Mysterious Minoans Were European, DNA Finds“The Minoans, the builders of Europe’s first advanced civilization, really were European, new research suggests…. ‘They were very similar to Neolithic Europeans and very similar to present day-Cretans,’ residents of the Mediterranean island of Crete.”

People Born With Certain Gene More Likely to Suffer Cognitive Decline After Heart Surgery“Long-term memory loss, difficulty understanding verbal or written communication or impaired ability to pay attention may still occur five years after heart surgery if a patient has a certain gene variation…. This gene was found to be related to a decline in cognitive capabilities compared to those who do not have the variation…. ‘Our study found that if a patient has this gene variation (APOE4), that person is more likely to have cognitive decline five years after surgery.'” – h/t hbd bibliography!

Genetics of eye colours in different rural populations on the Silk Road“[R]egression tree analysis showed that individuals carrying a given combination of haplotypes have a significant probability to show a blue or green/grey iris colour as compared with brown, with a gradient from west to east.” – h/t neuroskeptic!

Scanning for Recent Human Evolution

Evolution is not a one-way road towards complexity“[T]he fact that the highly complex larval muscular bodyplan is so similar in both groups [aplacophorans and chitons] but is only carried over into the adult stage in one of them — the chitons — strongly suggests that the common ancestor of both groups was of similar complexity; thereby implying that the worm-like groups lost these complex traits and became secondarily simplified over evolutionary time.”

Genomics England and the 100,000 genomes

National Geographic Agrees: The Human Alpha Male Is Real – from heartiste. see also “Manosphere” Community Beliefs: Truths and Nonsense from jayman.

Japan: A north-south cline in mental and behavioral traits – from peter frost.

What I actually said about genes, IQ and heritability“Rational public debate about genes and intelligence…has proved impossible in Britain and America….”

Heritability estimates and the analysis of variance“In terms that R.A. Fisher might have used, if you plant different strains of wheat in uniformly well ploughed, well mixed, well fertilised soil, then the differences between the different strains will be due to their inherent qualities, and not the vagaries of the soil. On the other hand, if the soil varies considerably then the yields will vary partly because of seed quality, and partly because of soil quality.” – from dr. james thompson.

Intelligence is just another privilege you inherited from mummy and daddy“[I]t is considered bad form for the clever to point out that their advantage is inherited. Yet this has the effect of giving the intellectually privileged the false idea that they have earned their advantage, and eroding the feeling of *noblesse oblige* that the wealthy once felt when they knew their fortune depended on luck. Rather we should regard intelligence as just another privilege you inherit from mummy and daddy…. That would make the world a more, not less, just place.” – from ed west.

The Stability of Intelligence From Age 11 to Age 90 Years: The Lothian Birth Cohort of 1921“The correlation of Moray House Test scores between age 11 and age 90 was .54 (.67 when corrected for range restriction).” – h/t john durant!

Can political polarization become baked in through assortative mating? – @steve sailer’s.

On the Unbearable Lightness of Objective Morality“Evolved behavioral predispositions are the ultimate reason for the existence of human morality. Absent those predispositions, our morality as we know it would cease to exist.” – from helian.

US regions exhibit distinct personalities, research reveals“Americans with similar temperaments are so likely to live in the same areas that a map of the country can be divided into regions with distinct personalities, according to new research published by the American Psychological Association. People in the north-central Great Plains and the South tend to be conventional and friendly, those in the Western and Eastern seaboards lean toward being mostly relaxed and creative, while New Englanders and Mid-Atlantic residents are prone to being more temperamental and uninhibited, according to a study published online by APA’s Journal of Personality and Social Psychology.”

Book Review: Why Evolution Is True (2009) by Jerry Coyne – book review from staffan.

Neanderthals Used Toothpicks to Alleviate the Pain of Diseases Related to Teeth, Such as Inflammation of the Gums – h/t andrew badenoch!

Women like their men with low voices, but only for a night“[W]omen were more attracted to men with low-pitched voices, which are produced by larger vocal cords. However, the research also showed women believed men with deeper voices were more likely to cheat.”

Epigenetics: How to alter your genes – well, you don’t really alter your genes with epigenetics, but your gene expression.

Oops! Etruscan Warrior Prince Really a Princess

bonus: Analysis of Racist Red Lobster Receipt Casts Doubt on Original Story and More restaurant receipt handwriting analysis – total race hoax – @gucci little piggy.

bonus bonus: New botox super-toxin has its [dna] details censored

bonus bonus bonus: Evolutionary Question Answered: Ants More Closely Related to Bees Than to Most Wasps. see also: Key to Ants’ Evolution May Have Started With a Wasp.

bonus bonus bonus bonus: Fossil scans reveal origins of teeth“Tooth-like structures originated from outer-body coverings.”

bonus bonus bonus bonus bonus: A new law of biology: All mammals pee for about 21 seconds @Why Evolution is True.

bonus bonus bonus bonus bonus bonus: Top Ten New Species: Snub-Nosed Monkey, More

bonus bonus bonus bonus bonus bonus bonus: Thirty million people are slaves, half in India

bonus bonus bonus bonus bonus bonus bonus bonus: Greek authorities appeal for help in finding real family of girl found in Gypsy camp.

(note: comments do not require an email. birds with mustaches!)

Inbred royals show traces of natural selection“Study suggests the Spanish Habsburgs evolved to mute the effects of inbreeding, but other geneticists are unconvinced.”

Time to get tough on the physiological causes of crime“[V]iolent criminals are biologically different from the rest of us.” – review of The Anatomy of Violence: The Biological Roots of Crime.

Scientists find ethnicity linked to antibodies“‘[I]t’s early days,’ emphasizes Watson, ‘but these findings could mean that past environmental exposures to certain pathogens caused DNA insertions or deletions in different ethnic groups, which could impact disease risk. Our results demonstrate that antibody studies need to take into account the ethnicity of DNA samples used.'”

Those resistant to ‘love hormone’ may also be easier to hypnotize“Gene variants linked to social detachment may increase suggestibility.”

One Blessing Of Outbreeding – i didn’t write this, i swear! (you’ll never guess who did…)

The gay germ hypothesis – from peter frost. see also Not Final! from greg cochran.

Another reminder…“[A] prod to certain of my smart liberal friends to start having children.” – from jayman. see also: The end of paternal investment or, more cads, fewer dads from mr. mangan.

The Strange Case of Dr. Robert Trivers“[Trivers] has been driven off the campus of Rutgers University! He has been involved in a controversy lately over his accusation that one of his graduate students committed fraud in a scientific paper. Apparently he was banned from campus because a colleague who supports the alleged fraudster claimed Trivers had ‘frightened him in his office’.” – from helian unbound.

Women graduates of elite colleges 1/3rd more likely to be stay-at-home moms – from steve sailer.

Scent of a Man: Women Can Sniff Out a Hot Guy“Women at their peak fertility prefer the smell of men oozing with testosterone, a new study finds.” – and speaking of testosterone: Testosterone pumps up threats for tough guys“The higher a man’s testosterone level, the more macho he’s likely to act when his masculinity is threatened, a new study finds.”

The Real ‘Hobbit’ Had Larger Brain Than Thought

Egyptian mummies yield genetic secrets“The ancient Egyptians could soon be getting their genomes sequenced as a matter of routine.”

Why Menopause?

Stonehenge occupied 5,000 years earlier than thought

The Pattern of Female Nuptiality in Oman“[M]ore than half (52%) of the total marriages in Oman are consanguineous. First cousin unions are the most common type of consanguineous unions, constituting 39% of all marriages and 75% of all consanguineous marriages. About 11% of the marriages are polygynous…. [P]aternal first-cousin marriages constituted 27.7% of all marriages and 72% (565/786) of all first-cousin marriages, while maternal first-cousin marriages constituted 10.8% of all marriages and 28% (221/786) of all first-cousin marriages.”

The Ancient Greeks & Romans, Beauty and Human Biodiversity – @occam’s razor.

Could Life Be Older Than Earth Itself?“[T]wo geneticists have applied Moore’s Law to the rate at which life on Earth grows in complexity — and the results suggest organic life first came into existence long before Earth itself.”

Chimps Communicate Like Passionate Italians – my favorite headline of the week. (^_^)

Live fast, die younger: Actors, singers and sportsman ‘die seven and a half years before other high achievers’

Historic human remains yield epigenetic tags – see also: Epigenetic Inheritance: Fact or Fiction?

Icelandic anti-incest app keeps residents from becoming kissin’ cousins – previously íslendingabók.

‘Real men wear kilts': The anecdotal evidence that wearing a Scottish kilt has influence on reproductive potential: how much is true? – keep wearin’ yer kilt!

Did this magical little crystal help the Vikings rape and pillage across the world?“Research suggests crystal salvaged from a shipwreck may be a sunstone”

bonus: What rights should Dzhokhar Tsarnaev get and why does it matter?“The Obama DOJ says it intends to question the Boston bombing suspect ‘extensively’ without first Mirandizing him”

bonus bonus: Applicants wanted for a one-way ticket to Mars – let’s go! (^_^)

bonus bonus bonus: ‘Living fossil’ genome unlocked“The genes of an ancient fish, the coelacanth, have much to reveal about our distant past.”

bonus bonus bonus bonus: Chlamydia Is Killing Koalas — Will Genetics Find a Cure?

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

late linkfest again! sorry. (*^_^*)

Group Selection (and homosexuality) and Homosexuality, epigenetics, and zebras – from greg cochran. also, from jayman –
A Gay Germ? Is Homophobia a Clue?

The Trouble with Epigenetics (Part 1)“[E]ven though epigenetic mechanisms may be involved in maintaining some stable traits over the lifetime of the animal, they are just that: mechanisms. Not causes. Epigenetics is not a source of variance, it is part of the mechanism whereby certain environmental factors or experiences have their effects.” (in other words, epigenetics is not magic.)

DNA ‘identichip’ gives a detailed picture of a suspect“The VisiGen team tested the chip on more than 3000 DNA samples collected around the world, and found that it was 99 per cent accurate at predicting gender. The chip also predicted European or East Asian ancestry with an accuracy of 97 per cent, and African ancestry in 88 per cent of cases. However, it was only 63 per cent accurate at predicting blond hair….”

What did our ancestors look like?“A new method of establishing hair and eye colour from modern forensic samples can also be used to identify details from ancient human remains….”

Black homicide rates by state – from the awesome epigone. compare to his White homicide rates by state. also, from hail: White Murder Rates by U.S. State, 1960 (vs. 2010).

People With Brown Eyes Appear More Trustworthy, But That’s Not The Whole Story“‘Brown-eyed individuals tend to be perceived as more trustworthy than blue-eyed ones,’ explain the authors. ‘But it is not brown eyes that cause this perception. It is the facial morphology linked to brown eyes.'” – see also dienekes.

Networking Ability a Family Trait in Monkeys“Social behaviors have been acted on by natural selection”

Cheating — and getting away with it“Scientists have found a gene that allows amoebae to pass on more than their fair share of their genes but doesn’t make them less fit in other ways”

Banded mongooses structure monosyllabic sounds in a similar way to humans

America’s Real Criminal Element: Lead“New research finds Pb is the hidden villain behind violent crime, lower IQs, and even the ADHD epidemic.” – maybe.

Darwin Was Wrong About Dating – maybe.

How Did Humans Figure Out That Sex Makes Babies?

bonus: #overlyhonestmethods is the PostSecret of the science world, and it is amazing – heh. (^_^)


bonus bonus: Why I Am Not an Atheist – from kanazawa.

bonus bonus bonus: Immigrant mothers in Britain could be aborting unwanted girls, ministers admit after study of birth rates

bonus bonus bonus bonus: Why is gingerism so common in Britain? – from ed west.

bonus bonus bonus bonus bonus: China’s one-child law: Less competitive adults?

(note: comments do not require an email. now that’s what i call a BIG turban!)

Investing Practices Significantly Heritable – from dennis mangan.

Fifty-seven Years of Darkness – @the loom.

Recent generations focus more on fame, money than giving back“Young adults less interested in community issues, politics and environment, finds new research”

Why do wealthy white conservative women have more children?“Because they are more religious and less educated than liberal women.” – from the inductivist.

Why are redheads less common than blondes? – from peter frost.

Epigenetics and epidemiology — hip, hype and science“Given the huge range of epigenetic variation and the relatively small effect size of environmental influences on the epigenome, investigation at the level of the individual may produce little but random noise. However … studied at the population level, epigenetics has much to offer to the understanding of disease aetiology and epidemiology has much to offer the field of epigenetics.”

Evan Charney’s Critique of Genopolitics and the Genetic Paradigm“Human genetics constrains but does not determine human cultures and human judgments.” – from larry arnhart.

bonus: Write Your Own Academic Sentence – e.g.: The construction of history as such functions as the conceptual frame for the culture of power/knowledge. – heh. (^_^)

bonus bonus: Women and Children First – wow. how can you have NO memory of childhood?

(note: comments do not require an email. “How to Deconstruct Almost Anything.”)


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