human self-domesti- cation events

the idea that humans have self-domesticated themselves (ourselves!) is definitely in vogue: here’s a recent irl+online symposium held on the topic.

domestication in mammals results in a specific suite of traits known as the “domestication syndrome”:

“[I]ncreased docility and tameness, coat color changes, reductions in tooth size, changes in craniofacial morphology, alterations in ear and tail form (e.g., floppy ears), more frequent and nonseasonal estrus cycles, alterations in adrenocorticotropic hormone levels, changed concentrations of several neurotransmitters, prolongations in juvenile behavior, and reductions in both total brain size and of particular brain regions.”

humans — in some cases some human populations — appear to exhibit many, if not all, of these traits: increased docility, skin color changes, reduction in tooth size, craniofacial feminization, more frequent/nonseasonal estrus cycle, neotenous gene expression in the developing human brain, prolongation in juvenile behavior, and reduction in total brain size.

much of the current thinking seems to be centered on the idea that humans self-domesticated “in the more distant past,” but the fact that humans have been able to dwell together at all in ridiculously large numbers beginning around the time of the agricultural revolution suggests that human self-domestication did not stop “in the more distant past” and is probably even ongoing. this is 10,000 Year Explosion territory, and cochran and harpending have been here already [pgs. 110-113 — my emphases]:

“If your ancestors were farmers for a long time, you’re descended from people who decided it was better to live on their knees than to die on their feet.

“Farming led to elites, and there was no avoiding their power. Foragers could walk away from trouble, but farms were too valuable (too important to the farmers’ fitness) to abandon. So farmers had to submit to authority: The old-style, independent-minded personalities that had worked well among egalitarian hunter-gatherers (‘A Man’s a Man for a’ That’) were obsolete. Even when some group had a chance to refound society on a more egalitarian basis, as in the case of the medieval Iceland republic, elites tended to reappear.

“Aggressive, combative people may also have experienced lowered fitness once ruling elites began to appear. With strong states, the personal payoff for aggression may have become smaller, while law and order made combativeness for self-defense less necessary. Sheer crowding must also have disfavored some personality traits that had worked in the past. Intuitively, it seems that a high level of aggressiveness would be less favored when encounters with strangers were frequent. Fight too often and you’re sure to lose. Moreover, although the winner of a deadly struggle between two peasants might conceivably gain something, his owners, the elites who taxed both of those peasants, would not, any more than a farmer benefits when one bull kills another.

“Farmers don’t benefit from competition between their domesticated animals or plants. In fact, reduced competition between individual members of domesticated species is the secret of some big gains in farm productivity, such as the dwarf strains of wheat and rice that made up the ‘Green Revolution.’ Since the elites were in a very real sense raising peasants, just as peasants raised cows, there must have been a tendency for them to cull individuals who were more aggressive than average, which over time would have changed the frequencies of those alleles that induced such aggressiveness. This would have been particularly likely in strong, long-lived states, because situations in which rebels often won might well have favored aggressive personalities. This meant some people were taming others, but with reasonable amounts of gene flow between classes, populations as a whole should have become tamer.

“We know of a gene that may play a part in this story: the 7R (for 7-repeat) allele of the DRD4 (dopamine receptor D4) gene. It is associated with Attention-Deficit/Hyperactivity Disorder (ADHD), a behavioral syndrome best characterized by actions that annoy elementary school teachers: restless-impulsive behavior, inattention, distractibility, and the like.

“The polymorphism is found at varying but significant levels in many parts of the world, but is almost totally absent from East Asia. Interestingly, alleles derived from the 7R allele are fairly common in China, even though the 7R alleles themselves are extremely rare there. It is possible that individuals bearing these alleles were selected against because of cultural patterns in China. The Japanese say that the nail that sticks out is hammered down, but in China it may have been pulled out and thrown away.

Selection for submission to authority sounds unnervingly like domestication. In fact, there are parallels between the process of domestication in animals and the changes that have occurred in humans during the Holocene period. In both humans and domesticated animals, we see a reduction in brain size, broader skulls, changes in hair color or coat color, and smaller teeth. As Dmitri Belyaev’s experiment with foxes shows, some of the changes that are characteristic of domesticated animals may be side effects of selection for tameness. As for humans, we know of a number of recent changes in genes involving serotonin metabolism in Europeans that may well influence personality, but we don’t know what effect those changes have had — since we don’t yet know whether they increase or decrease serotonin levels. Floppy ears are not seen in any human population (as far as we know), but then, changes in the external ear might interfere with recognition of speech sounds. Since speech is of great importance to fitness in humans, it may be that the negative effects of floppy ears have kept them from arising.

“Some of these favored changes could be viewed as examples of neoteny — retention of childlike characteristics. Children routinely submit to their parents — at least in comparison to teenagers — and it’s possible that natural selection modified mechanisms active in children in ways that resulted in tamer human adults, just as the behaviors of adult dogs often seem relatively juvenile in comparison with adult wolf behavior.

“If the strong governments made possible by agriculture essentially ‘tamed’ people, one might expect members of groups with shallow or nonexistent agricultural experience to be less submissive, on average, than members of longtime agricultural cultures. One possible indicator of tameness is the ease with which people can be enslaved, and our reading of history suggests that some peoples with little or no evolutionary exposure to agriculture ‘would not endure the yoke,’ as was said of Indians captured by the Puritans in the Pequot War of 1636. In the same vein, the typical Bushman, a classic hunter-gatherer, has been described as ‘the anarchist of South Africa.'”

what i’d like to draw attention to is the idea that there have been multiple (probably multiple multiples of) human self-domestication events which occurred at different places and at different times — all sorta within the broader human self-domestication project which began back in some stone age or, perhaps, even before. one of these, i propose, was the manorialism/outbreeding/execution-of-violent-criminals combo of medieval europe which left “core” europeans with a very specific set of behavioral traits. another might very well be whatever domestication package went along with rice farming in southern china as peter frost has discussed. others undoubtedly include the sorts of civilizations described by cochran & harpending in the passage quoted above — those “strong, long-lived states” — like those found in ancient egypt, ancient china, and ancient india.

just like how we (prolly together with dogs themselves) domesticated dogs thousands of years ago, but then continued and honed the process by selecting for specific traits in specific breeds, i think we should consider that, not only did humans start self-domesticating themselves a very long time ago so that there are common domestication traits in (nearly?) all humans populations, but also that there have been more localized self-domestication events which selected for somewhat different behavioral traits depending on what sort of selection pressures were present in these various events.

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why human biodiversity is true…and why jason richwine is right

human biodiversity — the set of biological and genetic differences between (and within) groups — is true because The Theory of Evolution is true, and since The Theory of Evolution is true, human biodiversity must be the case. (of course, The Theory of Evolution might be wrong. if so, everyone will have to head back to the drawing boards. but all the scientific indications are that The Theory is correct, so now it’s simply a matter of working out all the details.)

most of the hysteria surrounding jason richwine’s crimethink (i.e. that hispanics have a lower average iq than whites) is coming from the politically correct chattering classes — most of them on the left of course, but there are plenty of examples to be found on the right as well. these are people who probably claim to be smart (and most of them are probably pretty smart, actually), modern, and well-read. many of them are likely skeptics and atheists, too. most all of them no doubt “believe” in evolution. the problem is that they don’t understand evolution.

if they did understand evolution, they would know that, thanks to natural selection, genetic differences between populations having had long histories of developing in different types of environments are inevitable. and if they understood anything at all about biology (perhaps i’m asking too much), they would know that dna contributes to (not determines) variance in all sorts of traits in humans and other animals like personality, physique, and yes … intelligence. frankly, we’d be one really WEIRD species if there were NO differences between us all! (the pc-crowd would all probably be horrified to learn that this evolution in humans has sped up in the past 10,000 or so years thanks to the hugely increasing sizes of our populations — i.e. the more individuals you have, the more mutations there’s gonna be, and the more on which natural selection can work.)

so, the fact that the average iq of hispanics has been found, by many psychometricians btw, to be lower than the average iq of whites — and, i’ll note, that the average iq of whites has been found to be lower than the average iq of east asians — should not be surprising. that is, that there are differences between the average iqs of these different groups should not be surprising. those are the sorts of differences you’re gonna get with EVOLUTION.

do these differences mean that some peoples should be considered superior or inferior to others? no. do these differences mean that some peoples should be treated differently before the law (or in our daily lives for that matter)? of course not. do these differences mean that we should give pause for thought when considering which groups — and, perhaps more importantly, how many of any one group — to allow to immigrate to our country? absolutely!

jason richwine was right in his ph.d. thesis to suggest that we ought to consider the natures of the peoples we allow to immigrate to the u.s. if we want america to remain american in nature, since different peoples are different by nature. the addition of large numbers of foreigners to any country changes the culture and the workings of that country. jason has apparently said that immigrants to the u.s. in the past — the irish and the italians, for instance — successfully assimilated, while hispanics will not. i would suggest that what, in fact, happened was that the irish and the italians, et al., while assimilating to a certain degree also changed the nature of the country. perhaps less so than tens of millions of hispanics will do, but they altered it from a mostly anglo-saxon nation into a more generic western european nation.

all mass immigration serves to alter recipient nations to some degree or another. even the slightest bit of rational thinking based upon an understanding of evolution would lead anyone to realize that is an inevitable consequence of human biodiversity.

sadly, we live in irrational times.
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see also:
White v. Hispanic cognitive gap across 39 studies with 5,696,529 sample size from steve sailer.
Generations of Exclusion from greg cochran via steve sailer.
NYT: Dr. Richwine guilty of not being oblivious to the obvious from steve sailer.
“Burn The Witch!” Heritage Foundation Scuttles Away From Jason Richwine — And The Cold Hard Facts – from john derbyshire.
Christopher Jencks – “Who Should Get In?” – New York Review of Books from steve sailer.
The Crucifixion of Jason Richwine – from michelle malkin.
Jason Richwine and a bottle of Rich Wine from james thompson.
Jason Richwine’s Racial Theories Are Nothing New @the atlantic.
The IQ Test @slate.

further reading on human biodiversity:
– jayman’s hbd fundamentals
hbd bibliography

update: see also “to disbelieve in witchcraft is the greatest of heresies”

(note: comments do not require an email. two minutes of hate.)

tweaking just ONE gene…

…is all it takes to get some of the most recognizable of racial differences between human populations.

via steve sailer, from nicholas wade in the nyt:

East Asian Physical Traits Linked to 35,000-Year-Old Mutation

“Gaining a deep insight into human evolution, researchers have identified a mutation in a critical human gene as the source of several distinctive traits that make East Asians different from other races.

The traits — thicker hair shafts, more sweat glands, characteristically identified teeth and smaller breasts — are the result of a gene mutation that occurred about 35,000 years ago, the researchers have concluded….

“The first of those sites to be studied contains the gene known as EDAR. Africans and Europeans carry the standard version of the gene, but in most East Asians, one of the DNA units has mutated.

“Seeking to understand if the gene was the cause of thicker hair in East Asians with the variant gene, a team of researchers led by Yana G. Kamberov and Pardis C. Sabeti at the Broad Institute in Cambridge, Mass., decided to test the gene in mice, where its effects could be more easily explored….

“The Broad team engineered a strain of mice whose EDAR gene had the same DNA change as the East Asian version of EDAR.

When the mice grew up, the researchers found they did indeed have thicker hair shafts, confirming that the changed gene was the cause of East Asians’ thicker hair. But the gene had several other effects, they report in Thursday’s issue of the journal Cell.

One was that the mice, to the researchers’ surprise, had extra sweat glands. A Chinese member of the team, Sijia Wang, then tested people in China and discovered that they, too, had more numerous sweat glands, evidently another effect of the gene.

Another surprise was that the engineered mice had less breast tissue, meaning that EDAR could be the reason that East Asian women have generally smaller breasts.

“East Asians have distinctively shaped teeth for which their version of EDAR is probably responsible. But the mice were less helpful on this point; their teeth are so different from humans’ that the researchers could not see any specific change….

“A team led by Dr. Sabeti and Sharon R. Grossman of the Broad Institute has now refined the usual scanning methods and identified 412 sites on the genome that have been under selection. Each site is small enough that it contains at most a single gene.

Each race has a different set of selected regions, reflecting the fact that the human population had dispersed from its African homeland and faced different challenges that led to genetic adaptation on each continent. About 140 of the sites affected by natural selection are in Europeans, 140 in East Asians and 132 in Africans, the authors report in another article published Thursday in Cell….

so cool!

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“history as biology”

the best opening paragraph of a history book. ever!

from a book entitled Expansions: Competition and Conquest in Europe since the Bronze Age by an icelandic historian (or an icelandic fellow who trained as a historian, anyway), axel kristinsson [pg. 1]:

“1. History as Biology

“We are animals and the study of animals belongs to the realm of biology. I do not wish to sound extreme but the logic is inescapable. Our societies belong to the same general category as the societies of wolves or ants — groups of animals living together, interacting and depending on each other for their survival. Humans may very well be more interesting than either wolves or ants (at least to ourselves) and our societies are far more complex, which is why several scientific disciplines are dedicated to researching them. Nevertheless, they are *the same sort of things* as the societies of other animals, which is why we can expect some general principles of biology also to apply to humans and human society. In particular, human history should have some affinities to evolutionary biology. The evolution of human societies is the evolution of biological phenomena and the principles of evolution established by Charles Darwin might prove illuminating for human history as well.”

hear, hear!! (^_^)

unfortunately, he loses the thread pretty quickly [pg. 2]:

“Genetic evolution is an extremely slow process depending on random mutations and a reshuffling of genes to produce solutions that are beneficial to survival. These new genes then only become dominant over many generations as their benefits slowly assert themselves in the population. Significant changes often take millions of years.”

wrong. wrong, wrong, wrong.

still — the spirit is definitely right! (^_^)

(note: comments do not require an email. what icelandic people do for fun.)

evolution likes it hot

i posted about this before, but the topic came up in conversation recently, so i thought i’d post about it again:

“Evolution faster when it’s warmer”
24 June 2009

“Climate could have a direct effect on the speed of ‘molecular evolution’ in mammals, according to a study.

“Researchers have found that, among pairs of mammals of the same species, the DNA of those living in warmer climates changes at a faster rate.

“These mutations – where one letter of the DNA code is substituted for another – are a first step in evolution.

“The study, reported in Proceedings of the Royal Society B, could help explain why the tropics are so species-rich….

“The idea that microevolution happens faster in warmer environments is not new. But this is the first time the effect has been shown in mammals, which regulate their own body temperature.

“‘The result was unexpected,’ said Len Gillman from Auckland University of Technology, who led the study.

“‘We have previously found a similar result for plant species and other groups have seen it in marine animals. But since these are “ectotherms” – their body temperature is controlled directly by the environment – everyone assumed that the effect was caused by climate altering their metabolic rate….’

“‘We suspected the same effect might be happening in mammals, because seasonal changes affect the animals’ activity,’ Dr Gillman told BBC News.

“He and his team compared the DNA of 130 pairs of mammals, looking at genetically similar ‘sister species’ – where each of the pair lived at a different latitude or elevation.

“They tracked changes in one gene that codes for a protein known as cytochrome b, comparing the same gene in each of the pair of mammals to a “reference” gene in a common ancestor.

“By looking for mutations in the DNA code for this gene – each point where one letter in the code was substituted for another – the researchers were able to see which of the two mammals had ‘microevolved’ faster.

“Animals living in environments where the climate was warmer, had about 1.5 times more of these substitutions than the animals living in cooler environments.

“Dr Gillman explained that, at higher latitudes where environments are colder and less productive, animals often conserve their energy – hibernating or resting to reduce their metabolic activity.

“‘In warmer climates annual metabolic activity is likely to be greater, so this will lead to more total cell divisions per year in the germline.’

“These results support the idea that high tropical biodiversity is caused by faster rates of evolution in warmer climates.”
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here’s the original research article: Latitude, elevation and the tempo of molecular evolution in mammals

one of the first things that popped into my mind — right after cool! — when hearing about this a few years ago was: so what could this mean for the out-of-africa (ooa) theory? one of the foundational pillars of ooa is that, because genetic variation is greatest in africans, they must be some of the oldest populations on earth ’cause they’ve acquired so many, many mutations — therefore, everyone else prolly came ooa:

“A 10-year study published in 2009 analyzed the patterns of variation at 1,327 DNA markers of 121 African populations, 4 African American populations, and 60 non-African populations. The research showed that there is more human genetic diversity in Africa than anywhere else on Earth….

“Human genetic diversity decreases in native populations with migratory distance from Africa and this is thought to be the result of bottlenecks during human migration, which are events that temporarily reduce population size. It has been shown that variations in skull measurements decrease with distance from Africa at the same rate as the decrease in genetic diversity. These data support the Out of Africa theory over the multiregional origin of modern humans hypothesis.”

but if genetic variation might be increased just by living in a hot climate … well … then what?

more recently, davidski over at eurogenes posted about this paper the other day: An Abundance of Rare Functional Variants in 202 Drug Target Genes Sequenced in 14,002 People. turns out african americans have a lot more rare genetic variants than europeans — and northern europeans have the least of all:

could the differences be related to the fact that these people’s ancestors came from different latitudes/climates and, so, their mutation rates were different? dunno. maybe.

previously: here’s my question

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