linkfest – 08/31/14

African pygmies evolved their short stature twice“In the rainforests of Africa, being small is so helpful that it evolved twice in separate groups. Luis Barreiro of the University of Montreal in Quebec, Canada, and his colleagues identified 16 regions of the genome associated with short stature in the Batwa pygmies of Uganda. They then compared these regions in 169 Batwa and 74 Baka pygmies from West Africa. ‘In both groups, there was greater variation in those regions associated with being short, but no overlap between them,’ says Barreiro. This suggests they evolved their stature independently instead of inheriting the same ‘pygmy genes’ from a common ancestor.”

The strange history of the North American Arctic“Archaeologists mapping ancient cultures in the North American Arctic — a region spanning present-day Greenland — have long puzzled over how different cultures relate to one another. Now, an unprecedented large-scale genomics study has traced many such cultures to the Paleo-Eskimos, a people who early inhabited the harsh environment continuously for 4000 years, only to vanish mysteriously about 700 years ago. The discovery could change how scientists understand migration patterns in the North American Arctic…. After comparing the ancient and modern genetic data, the researchers found that the Saqqaq and Dorset cultures belonged to one Paleo-Eskimo people, whose genetic lineage continued in the region for more than 4000 years, from 3000 B.C.E. to 1300 C.E., contradicting previous theories that the diverse cultures came from different peoples. The Paleo-Eskimos are genetically distinct from Native Americans and Inuits, which means they represent a separate, later pulse of migration into the New World, says evolutionary geneticist Eske Willerslev of the University of Copenhagen, a co-author of the study. This contradicts previous theories that humans arrived in the Americas in three waves, painting a scenario of four waves instead — the Amerinds, the Na Dene Native Americans, the Paleo-Eskimos, and the Neo-Eskimo Thules…. What intrigues researchers most is why the Paleo-Eskimo lineage disappeared after the late Dorsets, around the same time that Neo-Eskimo Thules expanded rapidly to the Arctic. Archaeologists have found no evidence of violent conflict between the Thules and the Dorsets, but it would be hard to ignore contrasts between the two groups. The whale-hunting Thules lived in large, well-organized villages and boasted advanced technologies such as dog sleds and sinew-backed bows. The Dorsets, on the other hand, lived in small villages of 20 to 30 people and hunted with chipped stone blades. The researchers suspect that the Dorsets might have been pushed out to the fringes of the Arctic, or perhaps annihilated by a disease. ‘It’s just mind-blowing to imagine an entire people who just completely vanished,’ Willerslev says.” — see also Degüello from greg cochran.

Genetic changes transformed wild rabbits into tame bunnies, DNA study reveals“When humans domesticated wild rabbits and turned them into pet store favorites, they also changed their genome, a study has found…. The domestication of rabbits happened much more recently than that of cattle, sheep, pigs and dogs, which happened between about 15,000 and 9,000 years ago. Monks in monasteries in the south of France first domesticated northwestern europeans rabbits around 1,400 years ago…. [T]he researches report in the journal Science, small pre-existing genetic variations — sometimes just one letter of DNA code — started to become more common in the animals as they became domesticated. These variations generally didn’t affect the genes themselves, but rather acted on the genome’s regulatory regions, which are in control of whether genes are turned on or off. ‘Wild and domestic rabbits do not differ so much in actual protein sequences, but in how gene and protein expression is regulated,’ says Andersson. Among the genes particularly targeted during domestication were those involved in rabbits’ brains and nervous systems. That’s to be expected, Andersson says, because the differences between domestic and wild rabbits are almost all behavioral, while physical differences are slight…. Domestication of rabbits was made easier because the wild variety is a highly polymorphic species that already possesses many of gene variants selectively enhanced during domestication, the researchers say. That is likely to have been the case with most domesticated species, they say. ‘We predict that a similar process has occurred in other domestic animals and that we will not find a few specific genes that were critical for domestication,’ Andersson says.” — see also: Rabbit genome analysis reveals a polygenic basis for phenotypic change during domestication.

Comparative population genomics in animals uncovers the determinants of genetic diversity – h/t lars penke! who tweeted: “Across species, higher genetic diversity is not predicted by ecology, but by faster life history.”

Genome-wide genotype and sequence-based reconstruction of the 140,000 year history of modern human ancestry“We investigated ancestry of 3,528 modern humans from 163 samples. We identified 19 ancestral components, with 94.4% of individuals showing mixed ancestry. After using whole genome sequences to correct for ascertainment biases in genome-wide genotype data, we dated the oldest divergence event to 140,000 years ago. We detected an Out-of-Africa migration 100,000–87,000 years ago, leading to peoples of the Americas, east and north Asia, and Oceania, followed by another migration 61,000–44,000 years ago, leading to peoples of the Caucasus, Europe, the Middle East, and south Asia. We dated eight divergence events to 33,000–20,000 years ago, coincident with the Last Glacial Maximum. We refined understanding of the ancestry of several ethno-linguistic groups, including African Americans, Ethiopians, the Kalash, Latin Americans, Mozabites, Pygmies, and Uygurs, as well as the CEU sample. Ubiquity of mixed ancestry emphasizes the importance of accounting for ancestry in history, forensics, and health.” — don’t miss figure 2!

Seals May Have Carried Tuberculosis To The New World — thousand-year-old skeletons from peru suggest seals brought tuberculosis to americas.

Y Chromosomes of 40% Chinese Descend from Three Neolithic Super-Grandfathers“This observation suggests that the main patrilineal expansion in China occurred in the Neolithic Era and might be related to the development of agriculture.”

Blue Eyes Are More Common Than Any Other Colour in Britain“The Blue Eyes Project has found that although all eyes in Britain were once brown, they are now 48% blue, 30% green and just 22% brown…. The study mapped eye colour across the UK and Ireland and found that Scottish and Irish people are more likely to have blue eyes than in other parts of the UK, particularly the south. Just over a third (35%) of the population of south-west England and 41% in east England have blue eyes, compared to 57% in southeast Scotland…. Blue eyes are the result of a variant in the HERC2 gene, which, when it mutates, switches off the supply of brown-eye forming melanin, researchers say. Green eyes are also a result of this change, because they arise from a combination of the blue variant with brown. The first gene mutation resulting in blue eyes is understood to have occurred in the Baltic region around 10,000 years ago.”

Neanderthals in Europe Died Out Thousands of Years Sooner Than Some Thought, Study Says

The Other Neanderthal – h/t billare! who tweeted: “‘Denisovans are an example of…how mitochondrial DNA [misleads], & only the nuclear genome tells the full story.'”

Admixture in South African Afrikaners — from razib.

Finland’s love of milk dates back to the Stone Age“A combined team from the Universities of Bristol (England) and Helsinki (Finland) have been examining examples of Corded Ware pottery found in the northern parts of Finland. The pieces examined were cooking pots dated at 3,900 to 3,300 BCE and also approx. 2,500 BCE. Astonishingly the pots from 2,500 BCE contained traces of milk fats. This proved that the inhabitants at that time, despite a climate where it can snow for up to four months of the year, had domesticated animals.”

Holding a Mirror to Their Natures“[U]nrelated look-alikes showed little similarity in either personality or self-esteem. By contrast, twins — especially identical twins — score similarly on both scales, suggesting that the likeness is largely because of genetics…. Personality traits do not appear to be influenced by the way people are treated because of appearance. Moreover, they found, there appears to be no special bond between look-alikes. Helen Fisher, a biological anthropologist at Rutgers University who is also an identical twin, praised that study, saying it went to the heart of what makes people form a bond. ‘Even in cases where a person is a dead ringer for another, the natural pull is not there,’ Dr. Fisher said, ‘which builds the case that there is an underlying biology to kinship.'” — h/t steve stewart williams!

On the genetic architecture of intelligence and other quantitative traits — from steve hsu. h/t richard harper! who tweeted: “cognitive ability gene search requires sample sizes of 10,000 genes across a million persons.”

Genes Influence Young Children’s Human Figure Drawings and Their Association With Intelligence a Decade Later“Do genes influence individual differences in this species-typical behavior, and is drawing related to intelligence (g) in modern children? We report on the first genetically informative study of children’s figure drawing. In a study of 7,752 pairs of twins, we found that genetic differences exert a greater influence on children’s figure drawing at age 4 than do between-family environmental differences. Figure drawing was as heritable as g at age 4 (heritability of .29 for both). Drawing scores at age 4 correlated significantly with g at age 4 (r = .33, p < .001, n = 14,050) and with g at age 14 (r = .20, p < .001, n = 4,622). The genetic correlation between drawing at age 4 and g at age 14 was .52, 95% confidence interval = [.31, .75]. Individual differences in this widespread behavior have an important genetic component and a significant genetic link with g." – h/t rosalind arden!

Differences in intelligence between ethnic minorities and Han in China

The Canadian IQ calculated from the standardization of the WAIS IV eh? — h/t emil kirkegaard (no relation)!

Genome-wide screening for DNA variants associated with reading and language traits

Differences in cognitive abilities among primates are concentrated on G: Phenotypic and phylogenetic comparisons with two meta-analytical databases“Using meta-analytic databases of ethological observations of cognitive abilities involving 69 primate species, we found that cognitive abilities that load more strongly on a common factor (which is here termed G, in line with the terminology developed in previous literature to describe aggregated measures of general intelligence) are associated with significantly bigger interspecies differences and bigger interspecies variance. Additionally, two novel evolutionary predictions were made: more G-loaded abilities would present (1) weaker phylogenetic signals, indicating less phylogenetic conservativeness, and (2) faster rates of trait evolution, as it was hypothesized that G has been subjected to stronger selection pressures than narrower, more domain-specific abilities. These predictions were corroborated with phylogenetic comparative methods, with stronger effects among catarrhines (apes and Old World monkeys) than within the entire primate order. These data strongly suggest that G is the principal locus of selection in the macroevolution of primate intelligence. Implications for the understanding of population differences in cognitive abilities among human populations and for the theory of massive modularity applied to intelligence are discussed.” – h/t erwin schmidt!

The Flynn Effect: A Meta-Analysis [pdf] – h/t jelte wicherts! who tweeted: “IQ [continues] to go up with 3 points per decade. New meta-analysis shows no evidence of diminishing Flynn Effect.”

The Elusive X-Factor, or Why Jonathan Kaplan Is Wrong about Race and IQ – @humanvarieties.

Coevolution of languages and genes“[E]volutionary processes are more complex than simple models of gene-language coevolution predict, with linguistic boundaries only occasionally functioning as barriers to gene flow. More frequently, admixture takes place irrespective of linguistic differences, but with a detectable impact of contact-induced changes in the languages concerned.” – h/t jayman!

Does Natural Law exist?“While certain notions of right and wrong can apply to all humans, much of what we call ‘morality’ will always be population-dependent. What is moral in one population may not be in another.” – from peter frost.

Morality: The Amazing Side-Taking Machine“If there are so many evolutionary pathways to nice behaviors, and if many animals are cooperative, including bees, bats, hyenas, and monkeys, then perhaps the elaborate paraphernalia of human morality — explicit rules of behavior, moral taboos, moral debates, accusations, impartiality, punishments — are not needed to make people nice. Right? This is exactly what psychological research indicates. Developmental evidence shows that children are nice to people before acquiring adult-like moral judgment. Moreover, when children develop moral judgment, it does not prevent them from taking actions they judge wrong such as lying or stealing. In adults, research shows that moral judgments differ from and can even oppose altruistic motives. Research on hypocrisy shows that people are mostly motivated to appear moral rather than to actually abide by their moral judgments. Research on ‘motivated reasoning’ shows that people deviously craft moral justifications to push their own agendas. In short, people can be nice without morality and nasty with morality — altruism and morality are independent. In fact, humans are more eager to judge other people than to follow their own moral advice. Moral condemnation of other people’s behavior is distinctly, perhaps uniquely, human. So, what is the evolutionary function of condemnation…? People can use moral judgment to assess the wrongness of fighters’ actions and then choose sides against whoever was most immoral. When all bystanders use this strategy, they all take the same side and avoid the costs of escalated fighting. That is, moral condemnation functions to synchronize people’s side-taking decisions. This moral strategy is, of course, mostly unconscious just like other evolved programs for vision, movement, language, and so on.”

The roots of human altruism“[T]he willingness to provision others varies greatly from one primate species to the next. But there was a clear pattern, as summarized by Burkart: ‘Humans and callitrichid monkeys acted highly altruistically and almost always produced the treats for the other group members. Chimpanzees, one of our closest relatives, however, only did so sporadically.’ Similarly, most other primate species, including capuchins and macaques, only rarely pulled the lever to give another group member food, if at all – even though they have considerable cognitive skills. Until now, many researchers assumed that spontaneous altruistic behavior in primates could be attributed to factors they would share with humans: advanced cognitive skills, large brains, high social tolerance, collective foraging or the presence of pair bonds or other strong social bonds. As Burkart’s new data now reveal, however, none of these factors reliably predicts whether a primate species will be spontaneously altruistic or not. Instead, another factor that sets us humans apart from the great apes appears to be responsible. Says Burkart: ‘Spontaneous, altruistic behavior is exclusively found among species where the young are not only cared for by the mother, but also other group members such as siblings, fathers, grandmothers, aunts and uncles.’ This behavior is referred to technically as the ‘cooperative breeding’ or ‘allomaternal care.'”

Feminist activist women are masculinized in terms of digit-ratio and dominance: A possible explanation for the feminist paradox“The feminist movement purports to improve conditions for women, and yet only a minority of women in modern societies self-identify as feminists. This is known as the feminist paradox…. We measured the 2D:4D digit ratios (collected from both hands) and a personality trait known as dominance (measured with the Directiveness scale) in a sample of women attending a feminist conference. The sample exhibited significantly more masculine 2D:4D and higher dominance ratings than comparison samples representative of women in general, and these variables were furthermore positively correlated for both hands. The feminist paradox might thus to some extent be explained by biological differences between women in general and the activist women who formulate the feminist agenda.”

Global genetic variations predict brain response to faces“[A] significant proportion of the brain response to facial expressions is predicted by common genetic variance in a subset of regions constituting the face network. These regions show the highest inter-individual variability in the number of connections with other network nodes, suggesting that the genetic model captures variations across the adolescent brains in co-opting these regions into the face network.” – h/t razib!

Brain, behavior and genetics“Regardless of where the science now lies, we know that biology controls behavior. Our actions and thoughts aren’t magic, they rely on the biochemistry of neurotransmitters and nerve signals. They have physical substrates that are controlled by our genes….”

The impact of neighbourhood deprivation on adolescent violent criminality and substance misuse: A longitudinal, quasi-experimental study of the total Swedish population“We found that the adverse effect of neighbourhood deprivation on adolescent violent criminality and substance misuse in Sweden was not consistent with a causal inference.” — see also Depraved on account of being deprived? from dr. james thompson.

Does Urban Living Cause Mental Illness? – h/t jayman! who tweeted: “Interview w/ @AmirSariaslan, on his work showing that adverse environments don’t cause schizophrenia, & killing GxE.”

Daughters provide as much elderly parent care as they can, sons do as little as possible — h/t frau katze!

Honor: The Cause of — and Solution to — All of Society’s Problems“Centuries-old cultural norms don’t change overnight….” — gee, i wonder why? (where does culture come from?)

Social sciences suffer from severe publication bias“Survey finds that ‘null results’ rarely see the light of the day.” – h/t claire lehmann!

Haidt: “Political Diversity Will Improve Social Psychological Science” – from steve sailer.

How Do Liberal and Conservative Attitudes About Obedience to Authority Differ? The Surprising Result of My Study“Together with my collaborators Dr. Danielle Gaucher and Nicola Schaefer, we asked both red and blue Americans to share their views about obeying liberal authorities (e.g., ‘obey an environmentalist’). In an article that we recent published in Personality and Social Psychology Bulletin, we found that liberals were now the ones calling for obedience. And when the authorities were viewed as ideologically neutral (e.g., office manager), liberals and conservatives agreed. Only when people perceived the authority to be conservative (e.g., religious authority) did conservatives show a positive bias.”

The Kennewick Man Finally Freed to Share His Secrets

Measuring Inbreeding in the Greek Gods“it seems that Ares has an inbreeding coefficient of 37.5%. This is due to the fact that his parents—Zeus and Hera—are siblings, as well as his grandparents with each other. Zeus has an inbreeding coefficient of 25%.” — (^_^)

bonus: Walking fish raised on land mimic ancient evolutionary transition

bonus bonus: Why are all our wagtails vanishing? Scientists baffled by long-term decline of three species in Britain“The three wagtail species spotted on our shores are the Yellow Wagtail, a farmland bird that migrates to sub-Saharan Africa, and two which largely remain in the UK over the winter, the Grey Wagtail, a river specialist, and the familiar Pied Wagtail. Researchers said the races of both Pied and Yellow Wagtail breeding in the UK nest almost nowhere else in the world…. Sarah Harris, BBS Organiser at the British Trust for Ornithology, said: ‘I find it fascinating that three seemingly similar birds, the Yellow, Grey and Pied Wagtail can lead such different lives and face such a variety of challenges. With the UK races of two of these species – Pied and Yellow Wagtails – being largely confined to our islands, these population changes are of global conservation significance….'” – ornithologists are soooo waaaaycist! they make me sick! (~_^)

(note: comments do not require an email. biophobia. (~_^) )

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stop creating a climate of fear!

ok. listen up political correct people! if you’re someone who reflexively calls others “racists” or “neofascists” without first checking into whether or not they actually are, you need to STOP it, because you’re creating a climate of fear in which people are afraid to do their jobs.

and now i’m not talking about some academics sitting comfortably in their ivy towers, i’m talking about governmental agencies like THE POLICE and child welfare services. here’s where your pc moral posturing has gotten us today:

Revealed: How fear of being seen as racist stopped social workers saving up to 1,400 children from sexual exploitation at the hands of Asian men in just ONE TOWN

• Report found 1,400 children abused between 1997 and 2013 in Rotherham
• The figure is likely to be a conservative estimate of the true scale
• Victims terrorised with guns and doused in petrol and threatened with fire
• More than a third of the cases were already know to agencies
• Author of the report condemned ‘blatant’ failings by council’s leadership
Action blocked by political correctness as staff ‘feared appearing racist’
• Majority of victims described the perpetrators as ‘Asian’ men
• Leader of Rotherham Council has stepped down with immediate effect
• No council employees will receive disciplinary action, leaders state

don’t believe me? read the report from the independent investigator: Independent Inquiry into Child Sexual Exploitation in Rotherham (1997 – 2013) [pdf].

read about how girls (and some boys) as young as ELEVEN, many of whom were in care(!), were repeatedly gang raped, doped up, pimped out, sold out, trafficked, abused, and tortured (at least one girl was branded, although that may not have been in rotherham) — and then read how all of that was IGNORED by the child welfare(!) staff and police BECAUSE THEY WERE AFRAID OF BEING LABELLED RACISTS AND OF LOSING THEIR JOBS.

and if you’ve EVER called somebody a racist just because they said something politically incorrect, then you’d better bloody well read this report, because THIS IS ON YOU! this is YOUR doing! this is where your scare tactics have gotten us: over 1400 vulnerable kids systematically abused because YOU feel uncomfortable when anybody brings up some “hate facts.”

“hate facts” like this:

i don’t know what you want to do with that information, but you had better not even THINK about calling me a racist for pointing it out. enough is enough!

rotherham, the town in northern england where all this abuse has happened, is just the tip of the iceberg. the same systematic “grooming” of young girls and boys is happening in many other towns and cities in britain — we know this — the independent investigator knows this. and the authorities in those places are ALSO ignoring the problem for fear of being called racists.

this is YOUR fault, politically correct people — and i don’t care if you’re on the left or the right. YOU enabled this abuse thanks to the climate of fear you’ve created. thousands of abused girls — some of them maybe dead — on YOUR head.

think on that.
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see also: ‘I didn’t want to appear racist’ is the ‘I was only obeying orders’ of our age from ed west.

(note: comments do not require an email.)

what is human biodiversity (hbd)?

human biodiversity (hbd) is very simply the diversity found among and between human populations that has a biological basis.*

each of us is biologically unique. our genomes, our phenomes, our patterns of gene expression, our epigenomes, our microbiomes — none of these are ever exactly the same in any two individuals, even identical twins. yes, you are a special snowflake! you’re not even the same person today biologically that you were when you were six — or sixteen (unless you’re still sixteen, of course). for one thing, your patterns of gene expression as an adult are quite different from what you experienced as a toddler. each individual human is biologically diverse when compared to all other humans and even across his or her own lifetime. (got that last idea from steve sailer, btw.) and while we’re at it, you’re biologically diverse within yourself, too — cell by cell.

additionally, groups of genetically related individuals can exhibit average differences in various biological aspects (see more on this here). for example, immediate family members are more similar to each other genetically — and, usually, phenotypically — than they are to strangers. moving outwards from that circle, extended family members are also more similar to each other genetically than they are to strangers, although less so than are immediate family members. and the circle can be extended even further to: clan and tribe members, traditional villages and regions, ethnic groups, and races, until we reach the human race where we start comparing our collective biological traits to those of other species: primates, mammals, vertebrates, life on earth…. biodiversity in humans also exists between the sexes. remember that the biodiversity found in all these populations — which don’t necessarily have well-defined boundaries — includes features like epigenomes and microbiomes in addition to genomes.

hbd research is conducted in numerous academic disciplines and their subfields such as biology, genetics, medicine, neurology, psychology, and anthropology. hbd research also draws on social, historic, and prehistoric data related to human populations. (there is no separate academic discipline known as “human biodiversity.”)

*i’ve stolen that very elegant definition from claire lehmann.
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this is the first in a set of posts on What is Human Biodiversity? please, before you fire off a rant leave a comment here, check out the other posts, because your question or objection may have been dealt with in one of them. here they all are — you can read them in any order you choose! like to keep things interactive here on the hbd chick blog. (~_^) :

what human biodiversity (hbd) is not
examples of human biodiversity (hbd)
why human biodiversity (hbd) is true
hbd and racism
hbd and politics

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

what human biodiversity (hbd) is not

all i remember from the seventh grade — apart from the time some of the boys rolled the science teacher’s giant globe down the stairs (heh) — was endlessly taking reading comprehension tests. that must’ve been in vogue in education circles back then — check for reading comprehension! sheesh. seemed like every other day we took a comp test.

what i could never figure out at the time was how anyone could get any of the questions wrong on the tests! the tests typically consisted of three or four paragraphs that covered really dull and boring topics and which were followed by five or six multiple choice questions. but we still had the text in front of us when filling in the little ovals, so if you weren’t sure of an answer — was it bob that drove the car to the store or was it dan who took the bus to the movies? — you could just refer back to the text! what could possibly be simpler?! i know now, of course, that people have different abilities and that in any group half will be below average — and i went to a very average school — but at the time i was mystified. (yeah, prolly some of my fellow classmates just screwed around, too, and didn’t even try to answer the questions correctly.)

i have to admit, though, that that old bewildered feeling comes back to me again whenever someone misunderstands what hbd is.

human biodiversity.

it’s just TWO words, for chrissake!! two pretty straightforward words at that! how can anyone possibly misunderstand the phrase?!

ok. deep breath. let’s break it down. there’s “human” and there’s “biodiversity.” biodiversity is, i guess, one of those whatchamacallits — portmanteau words. it’s a combination of biological + diversity. i hope i don’t have to define either of them. and human? well, h. sapiens, i suppose, but if you want to throw in neanderthals or denisovans, that’d be okay.

so, what’ve we got? human biodiversity = the biological diversity of humans (see here). period. full stop.

here is where i’d like to note that human biodiversity is, thus, a set of natural phenomena — like chemical bonds or electromagnetic radiation. hbd is not a group of people — it’s the total variation of biological characteristics that all humans exhibit.

to be more specific: hbd is not an ideology. it is not a political platform. it is not even a set of beliefs. hbd is not a movement. of any sort.

hbd is not conservative or progressive. it’s not republican or democratic or independent or connected in any way to the mickey mouse party. it’s not libertarian, nor does it back a monarchy. hbd isn’t neo-fascist or neo-communist. or neo-confucian, neoconservative, neo-colonial, and/or neo-freudian.

hbd does not have feelings. or ideas. or even principles. it cannot advocate or suggest or imply or argue for or against or promote or claim anything. hbd does not have agency. saying that hbd “supports” anything is as ridiculous as saying that gravity “prefers” fluffy little bunny rabbits or that the second law of thermodynamics “was never really a big fan of” guy lombardo.

human biodiversity is just something we find in nature. that’s all.

there are obviously people who think hbd is particularly interesting — myself, for example. i guess we could be called “hbders” (hbd-ers?) — and here online there is something of an hbd-o-sphere — but that’s about it, really. to refer to the broad range of individuals who are interested in human biodiversity as “hbd” is simply misunderstanding the acronym.
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this is one of a set of posts on What is Human Biodiversity? please, before you fire off a rant leave a comment here, check out the other posts, because your question or objection may have been dealt with in one of them. here they all are!:

what is human biodiversity (hbd)?
examples of human biodiversity (hbd)
why human biodiversity (hbd) is true
hbd and racism
hbd and politics

(note: comments do not require an email. not hbd.)

examples of human biodiversity (hbd)

here’s a small smattering of examples of human biodiversity. a REALLY small smattering! just a handful of examples that i’ve thought of off the top of my head. i’ll keep adding to this list. feel free to help me out by leaving more examples in the comments! thanks. (^_^)

• eye color. people have different colored eyes, especially people of european descent. many genes are involved in eye color — not all of them are known yet.

• hair color. people have different colored hair, again especially people of european descent. and, again, we still don’t know all of the genes involved. yet.

• skin color. lots of different colors, obviously. still working out the genetics there, too.

• EDAR. a gene connected to embryonic development. from wikipedia: “A point mutation in EDAR, 370A, found in most East Asians but not common in African or European populations, is thought to be responsible for a number of differences between these populations, including the thicker hair, more numerous sweat glands, smaller breasts, and dentition characteristic of East Asians. The difference in dentition was not visible in mice due to the radically different structure of mice from human teeth, but it is considered reasonable that that difference also is due to the mutation. The 370A mutation arose in humans approximately 30,000 years ago, and now is found in 93% of Han Chinese and in the majority of people in nearby Asian populations.”

• sickle-cell trait. an adaptation giving a survival advantage in malarial regions, found especially in subsaharan africa, but unfortunately resulting in sickle-cell disease in some individuals. see here re. the genetics.

• lactase persistence. means you can have a starbucks latte without having to order soy milk. (~_^) from wikipedia: “Joel Hirschhorn of Harvard Medical School discovered that lactase persistence was due to the presence of a haplotype composed of more than 1 million nucleotide base pairs, including the lactase gene. The presence of this gene is the cause of lactase persistence. Today, this haplotype can be found in 80% of Europeans and Americans of European ancestry. On the other hand, the percentage of the population who are lactase persistent in sub-Saharan Africa and Southeast Asia is very low. It is absent in the Bantu of South Africa and most Chinese populations. These geographical distributions strongly correlate with the spread of domesticated cattle. About 5,000 to 10,000 years ago, this haplotype came under very strong selective pressure. This period matches the rise of dairy farming. As dairy farming originated in Europe, Europeans were exposed to increased lactose nutrition provided by dairy products, resulting in positive natural selection. The additional nutrition provided by the dairy was very important for survival in the recent history of Europe; therefore the supply of fresh milk leads to the favoring of the lactase persistent trait. As dairy farming spread across the globe, after the separation of Europe-derived populations from Asian- and African-derived populations, and after the colonization of Europe, the strong positive selection occurred in a large region, leading to the global spread of lactase persistence.” — there’re also a couple of other populations with lactase persistence stemming from different mutations.

• high-altitude adapation. there are different adapations in different populations, notably among the tibetans, the andeans, and the ethiopian highlanders. the tibetan adaptations seem to work the best, prolly because some of what they’ve got is really old.

• cold adaptations. in certain alleles in siberians. (i wish i had these!)

• height in pgymies. different subsaharan african pygmy populations show different height adaptations.

• ASPM. a gene connected to brain development. from wikipedia: “A new allele (version) of ASPM appeared sometime between 14,100 and 500 years ago with a mean estimate of 5,800 years ago. The new allele has a frequency of about 50% in populations of the Middle East and Europe, it is less frequent in East Asia, and has low frequencies among Sub-Saharan African populations. It is also found with an unusually high percentage among the people of Papua New Guinea, with a 59.4% occurrence.”

• microcephalin (MCPH1). another gene connected to brain development. from wikipedia: “A derived form of MCPH1 called haplogroup D appeared about 37,000 years ago (any time between 14,000 and 60,000 years ago) and has spread to become the most common form of microcephalin throughout the world except Sub-Saharan Africa; this rapid spread suggests a selective sweep. However, scientists have not identified the evolutionary pressures that may have caused the spread of these mutations. This variant of the gene is thought to contribute to increased brain volume. Modern distributions of chromosomes bearing the ancestral forms of MCPH1 and ASPM are correlated with the incidence of tonal languages, but the nature of this relationship is far from clear. Haplogroup D may have originated from a lineage separated from modern humans approximately 1.1 million years ago and later introgressed into humans. This finding supports the possibility of admixture between modern humans and extinct Homo spp. While Neanderthals have been suggested as the possible source of this haplotype, the haplotype was not found in the individuals used to prepare the first draft of the Neanderthal genome.”

• microbiomes. our microbiomes appear to vary between ethnic groups/races.

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this is one of a set of posts on What is Human Biodiversity? please, before you fire off a rant leave a comment here, check out the other posts, because your question or objection may have been dealt with in one of them. here they all are!:

what is human biodiversity (hbd)?
what human biodiversity (hbd) is not
why human biodiversity (hbd) is true
hbd and racism
hbd and politics

(note: comments do not require an email. great moments in evolution.)

why human biodiversity (hbd) is true

we know that human biodiversity (hbd) is true because, for one thing, we have many, many examples of it (see here)!

additionally, both the workings of the natural world and specifically the theory of evolution predict that hbd must be the case.

nature likes to throw up variety (see here for example) — the variation between individual organisms is, after all, what natural selection acts upon — and there’s no reason for humans to be any exception. add to that the fact that humans reproduce sexually — with all the genetic shuffling and remixing that happens there — and it’s inevitable that individual humans will be biologically diverse.

various groups or populations of humans — ranging from small-sized families to races and even beyond (for example, think: east asians+native americans together compared to caucasians or subsaharan africans) — will also inevitably be biologically diverse from one another, to greater or lesser degrees, due to forces of evolution such as natural selection, gene flow, and/or genetic drift.

keep in mind that humans — including various discrete-ish human populations (biological borders are fuzzy, naturally) — have experienced recent evolution (i.e. within the last 40,000 years or so), that human evolution has probably sped up since the advent of agriculture, and that we are undoubtedly still evolving today.

ignoring or denying the existence of human biodiversity won’t make it go away. hbd — and its implications — will remain a reality in spite of all your hopes and dreams, however well-intentioned they may be.
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this is one of a set of posts on What is Human Biodiversity? please, before you fire off a rant leave a comment here, check out the other posts, because your question or objection may have been dealt with in one of them. here they all are!:

what is human biodiversity (hbd)?
what human biodiversity (hbd) is not
examples of human biodiversity (hbd)
hbd and racism
hbd and politics

(note: comments do not require an email. another great moment in evolution.)