Review: Numbers and the Making of Us, by Caleb Everett

I’m about halfway through Caleb Everett’s Numbers and the Making of Us: Counting and the Course of Human Cultures. Everett begins the book with a lengthy clarification that he thinks everyone in the world has equal math abilities, some of us just happen to have been exposed to more number ideas than others. Once that’s out of the way, the book gets interesting.

When did humans invent numbers? It’s hard to say. We have notched sticks from the Paleolithic, but no way to tell if these notches were meant to signify numbers or were just decorated.

The slightly more recent Ishango, Lebombo, and Wolf bones (30,000 YA, Czech Republic) seem more likely to indicate that someone was at least counting–if not keeping track–of something.

The Ishango bone (estimated 20,000 years old, found in the Democratic Republic of the Congo near the headwaters of the Nile,) has three sets of notches–two sets total to 60, the third to 48. Interestingly, the notches are grouped, with both sets of sixty composed of primes: 19 + 17 + 13 + 11 and 9 + 19 + 21 + 11. The set of 48 contains groups of 3, 6, 4, 8, 10, 5, 5, and 7. Aside from the stray seven, the sequence tantalizingly suggests that someone was doubling numbers.

Ishango Bone

The Ishango bone also has a quartz point set into the end, which perhaps allowed it to be used for scraping, drawing, or etching–or perhaps it just looked nice atop someone’s decorated bone.

The Lebombo bone, (estimated 43-44,2000 years old, found near the border between South Africa and Swaziland,) is quite similar to the Ishango bone, but only contains 29 notches (as far as we can tell–it’s broken.)

I’ve seen a lot of people proclaiming “Scientists think it was used to keep track of menstrual cycles. Menstruating African women were the first mathematicians!” so I’m just going to let you in on a little secret: scientists have no idea what it was for. Maybe someone was just having fun putting notches on a bone. Maybe someone was trying to count all of their relatives. Maybe someone was counting days between new and full moons, or counting down to an important date.

Without a far richer archaeological assembly than one bone, we have no idea what this particular person might have wanted to count or keep track of. (Also, why would anyone want to keep track of menstrual cycles? You’ll know when they happen.)

The Wolf bone (30,000 years old, Czech Republic,) has received far less interest from folks interested in proclaiming that menstruating African women were the first mathematicians, but is a nice looking artifact with 60 notches–notches 30 and 31 are significantly longer than the others, as though marking a significant place in the counting (or perhaps just the middle of the pattern.)

Everett cites another, more satisfying tally stick: a 10,000 year old piece of antler found in the anoxic waters of Little Salt Spring, Florida. The antler contains two sets of marks: 28 (or possibly 29–the top is broken in a way that suggests another notch might have been a weak point contributing to the break) large, regular, evenly spaced notches running up the antler, and a much smaller set of notches set beside and just slightly beneath the first. It definitely looks like someone was ticking off quantities of something they wanted to keep track of.

Here’s an article with more information on Little Salt Spring and a good photograph of the antler.

I consider the bones “maybes” and the Little Salt Spring antler a definite for counting/keeping track of quantities.

Inca Quipu

Everett also mentions a much more recent and highly inventive tally system: the Incan quipu.

A quipu is made of knotted strings attached to one central string. A series of knots along the length of each string denotes numbers–one knot for 1, two for 2, etc. The knots are grouped in clusters, allowing place value–first cluster for the ones, second for the tens, third for hundreds, etc. (And a blank space for a zero.)

Thus a sequence of 2 knots, 4 knots, a space, and 5 knots = 5,402

The Incas, you see, had an empire to administer, no paper, but plenty of lovely alpaca wool. So being inventive people, they made do.

Everett then discusses the construction of names for numbers/base systems in different languages. Many languages use a combination of different bases, eg, “two twos” for four, (base 2,) “two hands” to signify 10 (base 5,) and from there, words for multiples of 10 or 20, (base 10 or 20,) can all appear in the same language. He argues convincingly that most languages derived their counting words from our original tally sticks: fingers and toes, found in quantities of 5, 10, and 20. So the number for 5 in a language might be “one hand”, the number for 10, “Two hands,” and the number for 20 “one person” (two hands + two feet.) We could express the number 200 in such a language by saying “two hands of one person”= 10 x 20.

(If you’re wondering how anyone could come up with a base 60 system, such as we inherited from the Babylonians for telling time, try using the knuckles of the four fingers on one hand [12] times the fingers of the other hand [5] to get 60.)

Which begs the question of what counts as a “number” word (numeral). Some languages, it is claimed, don’t have words for numbers higher than 3–but put out an array of 6 objects, and their speakers can construct numbers like “three twos.” Is this a number? What about the number in English that comes after twelve: four-teen, really just a longstanding mispronunciation of four and ten?

Perhaps a better question than “Do they have a word for it,” is “Do they have a common, easy to use word for it?” English contains the world nonillion, but you probably don’t use it very often (and according to the dictionary, a nonillion is much bigger in Britain than in the US, which makes it especially useless.) By contrast, you probably use quantities like a hundred or a thousand all the time, especially when thinking about household budgets.

Roman Numerals are really just an advanced tally system with two bases: 5 and 10. IIII are clearly regular tally marks. V (5) is similar to our practice of crossing through four tally marks. X (10) is two Vs set together. L (50) is a rotated V. C (100) is an abbreviation for the Roman word Centum, hundred. (I, V, X, and L are not abbreviations.) I’m not sure why 500 is D; maybe just because D follows C and it looks like a C with an extra line. M is short for Mille, or thousand. Roman numerals are also fairly unique in their use of subtraction in writing numbers, which few people do because it makes addition horrible. Eg, IV and VI are not the same number, nor do they equal 15 and 51. No, they equal 4 (v-1) and 6 (v+1,) respectively. Adding or multiplying large Roman numerals quickly becomes cumbersome; if you don’t believe me, try XLVII times XVIII with only a pencil and paper.

Now imagine you’re trying to run an empire this way.

You’re probably thinking, “At least those quipus had a zero and were reliably base ten,” about now.

Interestingly, the Mayans (and possibly the Olmecs) already had a proper symbol that they used for zero in their combination base-5/base-20 system with pretty functional place value at a time when the Greeks and Romans did not (the ancient Greeks were philosophically unsure about this concept of a “number that isn’t there.”)

(Note: given the level of sophistication of Native American civilizations like the Inca, Aztec, and Maya, and the fact that these developed in near total isolation, they must have been pretty smart. Their current populations appear to be under-performing relative to their ancestors.)

But let’s let Everett have a chance to speak:

Our increasingly refined means of survival and adaptation are the result of a cultural ratchet. This term, popularized by Duke University psychologist and primatologist Michael Tomasello, refers to the fact that humans cooperatively lock in knowledge from one generation to the next, like the clicking of a ratchet. In other word, our species’ success is due in large measure to individual members’ ability to learn from and emulate the advantageous behavior of their predecessors and contemporaries in their community. What makes humans special is not simply that we are so smart, it is that we do not have to continually come up with new solutions to the same old problems. …

Now this is imminently reasonable; I did not invent the calculus, nor could I have done so had it not already existed. Luckily for me, Newton and Leibniz already invented it and I live in a society that goes to great lengths to encode math in textbooks and teach it to students.

I call this “cultural knowledge” or “cultural memory,” and without it we’d still be monkeys with rocks.

The importance of gradually acquired knowledge stored in the community, culturally reified but not housed in the mind of any one individual, crystallizes when we consider cases in which entire cultures have nearly gone extinct because some of their stored knowledge dissipated due to the death of individuals who served as crucial nodes in their community’s knowledge network. In the case of the Polar Inuit of Northwest Greenland, population declined in the mid-nineteenth century after an epidemic killed several elders of the community. These elders were buried along with their tool sand weapons, in accordance with local tradition, and the Inuits’ ability to manufacture the tools and weapons in question was severely compromised. … As a result, their population did not recover until about 40 years later, when contact with another Inuit group allowed for the restoration of the communal knowledge base.

The first big advance, the one that separates us from the rest of the animal kingdom, was language itself. Yes, other animals can communicate–whales and birds sing; bees do their waggle dance–but only humans have full-fledged, generative language which allows us to both encode and decode new ideas with relative ease. Language lets different people in a tribe learn different things and then pool their ideas far more efficiently than mere imitation.

The next big leap was the development of visual symbols we could record–and read–on wood, clay, wax, bones, cloth, cave walls, etc. Everett suggests that the first of these symbols were likely tally marks such us those found on the Lebombo bone, though of course the ability to encode a buffalo on the wall of the Lascaux cave, France, was also significant. From these first symbols we developed both numbers and letters, which eventually evolved into books.

Books are incredible. Books are like external hard drives for your brain, letting you store, access, and transfer information to other people well beyond your own limits of memorization and well beyond a human lifetime. Books reach across the ages, allowing us to read what philosophers, poets, priests and sages were thinking about a thousand years ago.

Recently we invented an even more incredible information storage/transfer device: computers/the internet. To be fair, they aren’t as sturdy as clay tablets, (fired clay is practically immortal,) but they can handle immense quantities of data–and make it searchable, an incredibly important task.

But Everett tries to claim that cultural ratchet is all there is to human mathematical ability. If you live in a society with calculus textbooks, then you can learn calculus, and if you don’t, you can’t. Everett does not want to imply that Amazonian tribesmen with no words for numbers bigger than three are in any way less able to do math than the Mayans with their place value system and fancy zero.

But this seems unlikely for two reasons. First, we know very well that even in societies with calculus textbooks, not everyone can make use of them. Even among my own children, who have been raised with about as similar an environment as a human can make and have very similar genetics, there’s a striking difference in intellectual strengths and weaknesses. Humans are not identical in their abilities.

Moreover, we know that different mental tasks are performed in different, specialized parts of the brain. For example, we decode letters in the “visual word form area” of the brain; people whose VWAs have been damaged can still read, but they have to use different parts of their brains to work out the letters and they end up reading more slowly than they did before.

Memorably, before he died, the late Henry Harpending (of West Hunter) had a stroke while in Germany. He initially didn’t notice the stroke because it was located in the part of the brain that decodes letters into words, but since he was in Germany, he didn’t expect to read the words, anyway. It was only when he looked at something written in English later that day that he realized he couldn’t read it, and soon after I believe he passed out and was taken to the hospital.

Why should our brains have a VWA at all? It’s not like our primate ancestors did a whole lot of reading. It turns out that the VWA is repurposed from the part of our brain that recognizes faces :)

Likewise, there are specific regions of the brain that handle mathematical tasks. People who are better at math not only have more gray matter in these regions, but they also have stronger connections between them, letting the work together in harmony to solve different problems. We don’t do math by just throwing all of our mental power at a problem, but by routing it through specific regions of our brain.

Interestingly, humans and chimps differ in their ability to recognize faces and perceive emotions. (For anatomical reasons, chimps are more inclined to identify each other’s bottoms than each other’s faces.) We evolved the ability to recognize faces–the region of our brain we use to decode letters–when we began walking upright and interacting to each other face to face, though we do have some vestigial interest in butts and butt-like regions (“My eyes are up here.”) Our brains have evolved over the millenia to get better at specific tasks–in this case, face reading, a precursor to decoding symbolic language.

And there is a tremendous quantity of evidence that intelligence is at least partly genetic–estimates for the heritablity of intelligence range between 60 and 80%. The rest of the variation–the environmental part–looks to be essentially random chance, such as accidents, nutrition, or perhaps your third grade teacher.

So, yes, we absolutely can breed people for mathematical or linguistic ability, if that’s what the environment is selecting for. By contrast, if there have been no particular mathematical or linguistic section pressures in an environment (a culture with no written language, mathematical notation, and very few words for numbers clearly is not experiencing much pressure to use them), then you won’t select for such abilities. The question is not whether we can all be Newtons, (or Leibnizes,) but how many Newtons a society produces and how many people in that society have the potential to understand calculus, given the chance.

I do wonder why he made the graph so much bigger than the relevant part
Lifted gratefully from La Griffe Du Lion’s Smart Fraction II article

Just looking at the state of different societies around the world (including many indigenous groups that live within and have access to modern industrial or post-industrial technologies), there is clear variation in the average abilities of different groups to build and maintain complex societies. Japanese cities are technologically advanced, clean, and violence-free. Brazil, (which hasn’t even been nuked,) is full of incredibly violent, unsanitary, poorly-constructed favelas. Some of this variation is cultural, (Venezuela is doing particularly badly because communism doesn’t work,) or random chance, (Saudi Arabia has oil,) but some of it, by necessity, is genetic.

But if you find that a depressing thought, take heart: selective pressures can be changed. Start selecting for mathematical and verbal ability (and let everyone have a shot at developing those abilities) and you’ll get more mathematical and verbal abilities.

But this is getting long, so let’s continue our discussion next week.


2 Interesting studies: Early Humans in SE Asia and Genetics, Relationships, and Mental Illness

Ancient Teeth Push Back Early Arrival of Humans in Southeast Asia :

New tests on two ancient teeth found in a cave in Indonesia more than 120 years ago have established that early modern humans arrived in Southeast Asia at least 20,000 years earlier than scientists previously thought, according to a new study. …

The findings push back the date of the earliest known modern human presence in tropical Southeast Asia to between 63,000 and 73,000 years ago. The new study also suggests that early modern humans could have made the crossing to Australia much earlier than the commonly accepted time frame of 60,000 to 65,000 years ago.

I would like to emphasize that nothing based on a couple of teeth is conclusive, “settled,” or “proven” science. Samples can get contaminated, machines make errors, people play tricks–in the end, we’re looking for the weight of the evidence.

I am personally of the opinion that there were (at least) two ancient human migrations into south east Asia, but only time will tell if I am correct.

Genome-wide association study of social relationship satisfaction: significant loci and correlations with psychiatric conditions, by Varun Warrier, Thomas Bourgeron, Simon Baron-Cohen:

We investigated the genetic architecture of family relationship satisfaction and friendship satisfaction in the UK Biobank. …

In the DSM-55, difficulties in social functioning is one of the criteria for diagnosing conditions such as autism, anorexia nervosa, schizophrenia, and bipolar disorder. However, little is known about the genetic architecture of social relationship satisfaction, and if social relationship dissatisfaction genetically contributes to risk for psychiatric conditions. …

We present the results of a large-scale genome-wide association study of social
relationship satisfaction in the UK Biobank measured using family relationship satisfaction and friendship satisfaction. Despite the modest phenotypic correlations, there was a significant and high genetic correlation between the two phenotypes, suggesting a similar genetic architecture between the two phenotypes.

Note: the two “phenotypes” here are “family relationship satisfaction” and “friendship satisfaction.”

We first investigated if the two phenotypes were genetically correlated with
psychiatric conditions. As predicted, most if not all psychiatric conditions had a significant negative correlation for the two phenotypes. … We observed significant negative genetic correlation between the two phenotypes and a large cross-condition psychiatric GWAS38. This underscores the importance of social relationship dissatisfaction in psychiatric conditions. …

In other words, people with mental illnesses generally don’t have a lot of friends nor get along with their families.

One notable exception is the negative genetic correlation between measures of cognition and the two phenotypes. Whilst subjective wellbeing is positively genetically correlated with measures of cognition, we identify a small but statistically significant negative correlation between measures of correlation and the two phenotypes.

Are they saying that smart people have fewer friends? Or that dumber people are happier with their friends and families? I think they are clouding this finding in intentionally obtuse language.

A recent study highlighted that people with very high IQ scores tend to report lower satisfaction with life with more frequent socialization.

Oh, I think I read that one. It’s not the socialization per se that’s the problem, but spending time away from the smart person’s intellectual activities. For example, I enjoy discussing the latest genetics findings with friends, but I don’t enjoy going on family vacations because they are a lot of work that does not involve genetics. (This is actually something my relatives complain about.)

…alleles that increase the risk for schizophrenia are in the same haplotype as
alleles that decrease friendship satisfaction. The functional consequences of this locus must be formally tested. …

Loss of function mutations in these genes lead to severe biochemical consequences, and are implicated in several neuropsychiatric conditions. For
example, de novo loss of function mutations in pLI intolerant genes confers significant risk for autism. Our results suggest that pLI > 0.9 genes contribute to psychiatric risk through both common and rare genetic variation.

Two Exciting Papers on African Genetics

I loved that movie
Nǃxau ǂToma, (aka Gcao Tekene Coma,) Bushman star of “The Gods Must be Crazy,” roughly 1944-2003

An interesting article on Clues to Africa’s Mysterious Past appeared recently in the NY Times:

It was only two years ago that researchers found the first ancient human genome in Africa: a skeleton in a cave in Ethiopia yielded DNA that turned out to be 4,500 years old.

On Thursday, an international team of scientists reported that they had recovered far older genes from bone fragments in Malawi dating back 8,100 years. The researchers also retrieved DNA from 15 other ancient people in eastern and southern Africa, and compared the genes to those of living Africans.

Let’s skip to the article, Reconstructing Prehistoric African Population Structure by Skoglund et al:

We assembled genome-wide data from 16 prehistoric Africans. We show that the anciently divergent lineage that comprises the primary ancestry of the southern African San had a wider distribution in the past, contributing approximately two-thirds of the ancestry of Malawi hunter-gatherers ∼8,100–2,500 years ago and approximately one-third of the ancestry of Tanzanian hunter-gatherers ∼1,400 years ago.

Paths of the great Bantu Migration

The San are also known as the Bushmen, a famous group of recent hunter-gatherers from southern Africa.

We document how the spread of farmers from western Africa involved complete replacement of local hunter-gatherers in some regions…

This is most likely the Great Bantu Migration, which I wrote about in Into Africa: the Great Bantu Migration.

…and we track the spread of herders by showing that the population of a ∼3,100-year-old pastoralist from Tanzania contributed ancestry to people from northeastern to southern Africa, including a ∼1,200-year-old southern African pastoralist…

Whereas the two individuals buried in ∼2,000 BP hunter-gatherer contexts in South Africa share ancestry with southern African Khoe-San populations in the PCA, 11 of the 12 ancient individuals who lived in eastern and south-central Africa between ∼8,100 and ∼400 BP form a gradient of relatedness to the eastern African Hadza on the one hand and southern African Khoe-San on the other (Figure 1A).

The Hadza are a hunter-gatherer group from Tanzania who are not obviously related to any other people. Their language has traditionally been classed alongside the languages of the KhoiSan/Bushmen people because they all contain clicks, but the languages otherwise have very little in common and Hadza appears to be a language isolate, like Basque.

The genetic cline correlates to geography, running along a north-south axis with ancient individuals from Ethiopia (∼4,500 BP), Kenya (∼400 BP), Tanzania (both ∼1,400 BP), and Malawi (∼8,100–2,500 BP), showing increasing affinity to southern Africans (both ancient individuals and present-day Khoe-San). The seven individuals from Malawi show no clear heterogeneity, indicating a long-standing and distinctive population in ancient Malawi that persisted for at least ∼5,000 years (the minimum span of our radiocarbon dates) but which no longer exists today. …

We find that ancestry closely related to the ancient southern Africans was present much farther north and east in the past than is apparent today. This ancient southern African ancestry comprises up to 91% of the ancestry of Khoe-San groups today (Table S5), and also 31% ± 3% of the ancestry of Tanzania_Zanzibar_1400BP, 60% ± 6% of the ancestry of Malawi_Fingira_6100BP, and 65% ± 3% of the ancestry of Malawi_Fingira_2500BP (Figure 2A). …

Both unsupervised clustering (Figure 1B) and formal ancestry estimation (Figure 2B) suggest that individuals from the Hadza group in Tanzania can be modeled as deriving all their ancestry from a lineage related deeply to ancient eastern Africans such as the Ethiopia_4500BP individual …

So what’s up with the Tanzanian expansion mentioned in the summary?

Western-Eurasian-related ancestry is pervasive in eastern Africa today … and the timing of this admixture has been estimated to be ∼3,000 BP on average… We found that the ∼3,100 BP individual… associated with a Savanna Pastoral Neolithic archeological tradition, could be modeled as having 38% ± 1% of her ancestry related to the nearly 10,000-year-old pre-pottery farmers of the Levant These results could be explained by migration into Africa from descendants of pre-pottery Levantine farmers or alternatively by a scenario in which both pre-pottery Levantine farmers and Tanzania_Luxmanda_3100BP descend from a common ancestral population that lived thousands of years earlier in Africa or the Near East. We fit the remaining approximately two-thirds of Tanzania_Luxmanda_3100BP as most closely related to the Ethiopia_4500BP…

…present-day Cushitic speakers such as the Somali cannot be fit simply as having Tanzania_Luxmanda_3100BP ancestry. The best fitting model for the Somali includes Tanzania_Luxmanda_3100BP ancestry, Dinka-related ancestry, and 16% ± 3% Iranian-Neolithic-related ancestry (p = 0.015). This suggests that ancestry related to the Iranian Neolithic appeared in eastern Africa after earlier gene flow related to Levant Neolithic populations, a scenario that is made more plausible by the genetic evidence of admixture of Iranian-Neolithic-related ancestry throughout the Levant by the time of the Bronze Age …and in ancient Egypt by the Iron Age …

There is then a discussion of possible models of ancient African population splits (were the Bushmen the first? How long have they been isolated?) I suspect the more ancient African DNA we uncover, the more complicated the tree will become, just as in Europe and Asia we’ve discovered Neanderthal and Denisovan admixture.

They also compared genomes to look for genetic adaptations and found evidence for selection for taste receptors and “response to radiation” in the Bushmen, which the authors note “could be due to exposure to sunlight associated with the life of the ‡Khomani and Ju|’hoan North people in the Kalahari Basin, which has become a refuge for hunter-gatherer populations in the last millenia due to encroachment by pastoralist and agriculturalist groups.”

(The Bushmen are lighter than Bantus, with a more golden or tan skin tone.)

They also found evidence of selection for short stature among the Pygmies (which isn’t really surprising to anyone, unless you thought they had acquired their heights by admixture with another very short group of people.)

Overall, this is a great paper and I encourage you to RTWT, especially the pictures/graphs.

Now, if that’s not enough African DNA for you, we also have Loci Associated with Skin Pigmentation Identified in African Populations, by Crawford et al:

Examining ethnically diverse African genomes, we identify variants in or near SLC24A5, MFSD12, DDB1, TMEM138, OCA2 and HERC2 that are significantly associated with skin pigmentation. Genetic evidence indicates that the light pigmentation variant at SLC24A5 was introduced into East Africa by gene flow from non-Africans. At all other loci, variants associated with dark pigmentation in Africans are identical by descent in southern Asian and Australo-Melanesian populations. Functional analyses indicate that MFSD12 encodes a lysosomal protein that affects melanogenesis in zebrafish and mice, and that mutations in melanocyte-specific regulatory regions near DDB1/TMEM138 correlate with expression of UV response genes under selection in Eurasians.

I’ve had an essay on the evolution of African skin tones sitting in my draft folder for ages because this research hadn’t been done. There’s plenty of research on European and Asian skin tones (skin appears to have significantly lightened around 10,000 years ago in Europeans,) but much less on Africans. Luckily for me, this paper fixes that.

Looks like SLC24A5 is related to that Levantine/Iranian back-migration into Africa documented in the first paper.

Zoroastrian (Parsi) DNA

Farvahar. Persepolis, Iran.

Zoroastrianism is one of the world’s oldest surviving religions and possibly its first monotheistic one. It emerged in now-Iran about 3,000 years ago, but following the Arab (Islamic) conquest of Persia, many Zoroastrians migrated to India, where they became known as the Parsi (from the word for “Persian.”) To be clear, where this post refers to “Parsis” it means the specific Zoroastrian community in India, and where it refers to “Iranian Zoroastrians” it means the Zoroastrians currently living in Iran.

Although Zoroastrianism was once the official state religion of Persia, today only about 190,000 believers remain (according to Wikipedia,) and their numbers are declining.

If you’re thinking that a diasporic community of monotheists sounds familiar, you’re in good company. According to Wikipedia:

Portuguese physician Garcia de Orta observed in 1563 that “there are merchants … in the kingdom of Cambaia … known as Esparcis. We Portuguese call them Jews, but they are not so. They are Gentios.”

Another parallel: Ashkenazi Jews and Parsis are both reported to be very smart. Famous Parsis include Queen Guitarist Freddy Mercury, nuclear physicist Homi J. Bhabha, and our Harvard-employed friend, Homi K. Bhabha.

Lopez et al have recently carried out a very interesting study of Zoroastrian DNA, The Genetic Legacy of Zoroastrianism in Iran and India: Insights into Population Structure, Gene Flow, and Selection:

Historical records indicate that migrants from Persia brought Zoroastrianism to India, but there is debate over the timing of these migrations. Here we present genome-wide autosomal, Y chromosome, and mitochondrial DNA data from Iranian and Indian Zoroastrians and neighboring modern-day Indian and Iranian populations and conduct a comprehensive genome-wide genetic analysis in these groups. … we find that Zoroastrians in Iran and India have increased genetic homogeneity relative to other sampled groups in their respective countries, consistent with their current practices of endogamy. Despite this, we infer that Indian Zoroastrians (Parsis) intermixed with local groups sometime after their arrival in India, dating this mixture to 690–1390 CE and providing strong evidence that Iranian Zoroastrian ancestry was maintained primarily through the male line.

Note that all diasporic–that is, migrant–groups appear to be heavily male. Women tend to stay put while men move and take new wives in their new homelands.

By making use of the rich information in DNA from ancient human remains, we also highlight admixture in the ancestors of Iranian Zoroastrians dated to 570 BCE–746 CE, older than admixture seen in any other sampled Iranian group, consistent with a long-standing isolation of Zoroastrians from outside groups. …

Admixture with whom? (Let’s just read the paper and see if it answers the question):

Furthermore, a recent study using genome-wide autosomal DNA found that haplotype patterns in Iranian Zoroastrians matched more than other modern Iranian groups to a high-coverage early Neolithic farmer genome from Iran

A study of four restriction fragment length polymorphisms (RFLPs) suggested a closer genetic affinity of Parsis to Southern Europeans than to non-Parsis from Bombay. Furthermore, NRY haplotype analysis and patterns of variation at the HLA locus in the Parsis of Pakistan support a predominately Iranian origin. …

In (1) and (2), we detected admixture in the Parsis dated to 27 (range: 17–38) and 32 (19–44) generations ago, respectively, in each case between one predominantly Indian-like source and one predominantly Iranian-like source. This large contribution from an Iranian-like source (∼64%–76%) is not seen in any of our other 7 Indian clusters, though we detect admixture in each of these 7 groups from wide-ranging sources related to modern day individuals from Bangladesh, Cambodia, Europe, Pakistan, or of Jewish heritage (Figures 2 and S7, Tables S5–S7). For Iranian Zoroastrians, we detect admixture only under analysis (2), occurring 66 (42–89) generations ago between a source best genetically explained as a mixture of modern-day Croatian and Cypriot samples, and a second source matching to the Neolithic Iranian farmer WC1. … The two Iranian Zoroastrians that had been excluded as outliers exhibited admixture patterns more similar to the Lebanese, Turkish Jews, or Iranian Bandari individuals than to Zoroastrians (Table S8).

Parsi Wedding, 1905

If I assume a generation is about 25 years long, 27 generations was about 675 years ago; 32 was about 800 years ago. (Though given the wide range on these dates, perhaps we should estimate between 425 and 1,100 years ago.) This sounds consistent with Parsis taking local wives after they arrived in India between the 8th and 10th century CE (after the Arab conquest of Perisa.) Also consistently, this admixture isn’t found in Iranian Zoroastrians.

The Iranians’ admixture occurred about 1,050 and 2,225 years ago, which is an awfully broad time range. Could Croatian or Cypriot migrants have arrived due to the Greek/Roma/ Byzantine Empires? Were they incorporated into the Persian Empire as a result of its territorial conquests or the Arab conquest? Or were they just long-distance merchants who happened to wander into the area?

The Fire Temple of Baku

The authors found that Parsi priests had “the lowest gene diversity values of all population samples studied for both Y and mtDNA,” though they didn’t have enough Iranian Zoroastrian priest samples to compare them to Parsi priests. (I bet this is similar to what you’d find if you sampled Orthodox rabbis.)

Finally, in the genetic selection and diseases section, the authors write:

In the case of the Iranian Zoroastrians, … some of the most significant SNPs… are located upstream of gene SLC39A10 … with an important role in humoral immunity61 or in CALB2 … which plays a major role in the cerebellar physiology.62

With regard to the positive selection tests on Parsis versus India Hindu/Gujarati groups, the most significant SNPs were embedded in WWOX … associated with neurological disorders like early epilepsy … and in a region in chromosome 20 … (see Table S11 for a complete list). …

Genetic isolation and endogamous practices can be associated with higher frequencies of disease prevalence. For example, there are reports claiming a high recurrence of diseases such as diabetes among the Iranian Zoroastrians, and Parkinson, colon cancer, or the deficiency of G6PD, an enzyme that triggers the sudden reduction of red blood cells, among the Parsis.

However, the authors warn that these results are weak (these are rare conditions in an already small population) and cannot not be depended upon.

Musical Mystery

Singer Tom Jones, famous recipient of ladies’ panties

There are three categories of supersars who seem to attract excessive female interest. The first is actors, who of course are selected for being abnormally attractive and put into romantic and exciting narratives that our brains subconsciously interpret as real. The second are sports stars and other athletes, whose ritualized combat and displays of strength obviously indicate their genetic “fitness” for siring and providing for children.

The third and strangest category is professional musicians, especially rock stars.

I understand why people want to pass athletic abilities on to their children, but what is the evolutionary importance of musical talent? Does music tap into some deep, fundamental instinct like a bird’s attraction to the courtship song of its mate? And if so, why?

There’s no denying the importance of music to American courtship rituals–not only do people visit bars, clubs, and concerts where music is being played in order to meet potential partners, but they also display musical tastes on dating profiles in order to meet musically-like-minded people.

Of all the traits to look for in a mate, why rate musical taste so highly? And why do some people describe their taste as, “Anything but rap,” or “Anything but country”?

Mick Jagger and Chuck Berry

At least when I was a teen, musical taste was an important part of one’s “identity.” There were goths and punks, indie scene kids and the aforementioned rap and country fans.

Is there actually any correlation between musical taste and personality? Do people who like slow jazz get along with other slow jazz fans better than fans of classical Indian? Or is this all compounded by different ethnic groups identifying with specific musical styles?

Obviously country correlates with Amerikaner ancestry; rap with African American. I’m not sure what ancestry is biggest fans of Die Antwoord. Heavy Metal is popular in Finno-Scandia. Rock ‘n Roll got its start in the African American community as “Race Music” and became popular with white audiences after Elvis Presley took up the guitar.

While Europe has a long and lovely musical heritage, it’s indisputable that African Americans have contributed tremendously to American musical innovation.

Here are two excerpts on the subject of music and dance in African societies:

source: A Voyage to Senegal: The Isle of Goreé, and the River Gambia by  Michel Adanson, Correspondent of the Royal Academy of Sciences


source: Africana: The Encyclopedia of the African and African American Experience Aardvark-Catholic. Vol. 1
Elvis’s pelvis, considered too sexy for TV

Both of these h/t HBD Chick and my apologies in advance if I got the sources reversed.

One of the major HBD theories holds that the three races vary–on average–in the distribution of certain traits, such as age of first tooth eruption or intensity of an infant’s response to a tissue placed over its face. Sub-Saharan Africans and Asians are considered two extremes in this distribution, with whites somewhere in between.

If traditional African dancing involves more variety in rhythmic expression than traditional European, does traditional Asian dance involve less? I really know very little about traditional Asian music or dance of any kind, but I would not be surprised to see some kind of continuum affected by whether a society traditionally practiced arranged marriages. Where people chose their own mates, it seems like they display a preference for athletic or musically talented mates (“sexy” mates;) when parents chose mates, they seem to prefer hard-working, devout, “good providers.”

Natasha Rostova and Andrei Bolkonsky, from War and Peace by Tolstoy

Even in traditional European and American society, where parents played more of a role in courtship than they do today, music still played a major part. Young women, if their families could afford it, learned to play the piano or other instruments in order to be “accomplished” and thus more attractive to higher-status men; young men and women often met and courted at musical events or dances organized by the adults.

It is undoubtedly true that music stirs the soul and speaks to the heart, but why?


Open Thread: Announcement

341ea6e08a49012ee3c400163e41dd5bI’m starting some new IRL projects (that have nothing to do with the blog and won’t be discussed here.) It’s a big time commitment and if all goes well, I’m going to be really busy for the foreseeable future.

Right now I have no idea how this will affect the blog, whether I’ll be figure out how to balance my time and keep up my regular schedule or will need to cut back. I’ll let you know when I find out.

(Update: hooo boy has life been kicking my butt.)

m3-agenesis-carter-worthington-2015In the meanwhile, here’s a graph of the incidence of people who never develop their permanent third molars, broken down by continent (I assume N. and S. America are sampled from Native American populations.)

This is not the same as not getting your wisdom teeth, though I’d wager a graph of that would look similar.

(“agenesis”= does not begin; “m3″= third molar.)

male-heights-from-skeletons-in-europe-1-2000-clark-645x403And a simple graph of heights in the US, Europe and Sweden over the past … 2000 years.

I propose that the recent increase in heights isn’t just because of better nutrition/more food/more milk and protein in the diet, but also because fewer women die giving birth to large babies now that we have c-sections, and large babies likely grow into large adults.

hybridThis is just a joke. It has no deeper meaning.

In interesting news:

Lethal aggression in Pan [chimpanzees] is better explained by adaptive strategies than human impacts:

Observations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) provide valuable comparative data for understanding the significance of conspecific killing. … Lethal violence is sometimes concluded to be the result of adaptive strategies, such that killers ultimately gain fitness benefits by increasing their access to resources such as food or mates. Alternatively, it could be a non-adaptive result of human impacts, such as habitat change or food provisioning. To discriminate between these hypotheses we compiled information from 18 chimpanzee communities and 4 bonobo communities studied over five decades. Our data include 152 killings (n = 58 observed, 41 inferred, and 53 suspected killings) by chimpanzees in 15 communities and one suspected killing by bonobos. We found that males were the most frequent attackers (92% of participants) and victims (73%); most killings (66%) involved intercommunity attacks; and attackers greatly outnumbered their victims (median 8:1 ratio). Variation in killing rates was unrelated to measures of human impacts. Our results are compatible with previously proposed adaptive explanations for killing by chimpanzees, whereas the human impact hypothesis is not supported.

Behind the Murky World of Albanian Blood Feuds:

…He produces a list of recent killings he contends are the result of feuding families – not just random acts of violence in a country awash with guns, but the result of continued adherence to an ancient Albanian code of justice known as the “kanun”, or canon.

There is a farmer who was killed after cutting down his neighbour’s tree, a lover who shot both his girlfriend’s brothers after being denied her hand in marriage, and a returning migrant worker gunned down after he went back to his village, reigniting a decades-old feud.

Such are the rules of the “kanun”, a tribal code of 1,262 rules laid down by the 15th-century Albanian nobleman Lekë Dukagjini, which ordains that “spilled blood must be met with spilled blood”.

But while the Kanun stories remain part of Albania’s cultural and historical DNA, they are also a source of growing concern for Britain’s asylum tribunals. Since 2012 tens of thousands of Albanians have migrated to Europe, many seeking asylum on the basis that they are afraid for their lives as a result of “blood feuds”. …

Darwinian Perspectives on the Evolution of Human Languages:

Herodotus, writing in the Histories, Book II.53 around 450 BCE, remarked that Homer “lived, as I believe, not more than 400 years ago.” Many modern classicists and historians prefer a more recent, mid-8th century date for the Iliad. We (Altschuler, Calude, Meade, & Pagel, 2013) decided to try to estimate a date for the Iliad by investigating patterns of cognacy among the 200 words of Swadesh’s (1952) fundamental vocabulary in three languages: Modern Greek, Homeric Greek from Homer’s Iliad, and Hittite, a language distantly related to both modern and Homeric Greek.

We first recorded whether each word in the Swadesh list was cognate or not between pairs of the three languages. Then, we solved for the date in history that was the most likely for the Iliad, given our knowledge of the rates of change of the words and the patterns of cognacy we observed. Our calculation suggested that the original text of the Iliad was released in approximately 762 BCE. This date is in close agreement with classicists’ and historians’ beliefs arrived at independently by studying historical references and the nature of Homeric Greek as expressed in the Iliad.

Staffordshire Strikes Gold with Iron Age Find:

An archaeological find on Staffordshire farmland is believed to include the earliest examples of Iron Age gold ever discovered in Britain.

The collection, which has been named the Leekfrith Iron Age Torcs, was discovered by two metal detectorists just before Christmas.

Unveiling the torcs today (February 28), experts said the unique find could date back as far as 400BC and was of huge international importance.

For Comment of the Week, I’ve been enjoying the conversation between multiple commentators about Fishing and Fish Sauce over on What Mental Traits does the Arctic Select For?

E: … I know in terms of iodine deficiency, pre-modern-transport and storage, distance from the sea makes a big difference. And probably in a well-ordered place with relatively good transport like the Roman Empire at its height, fish sauce must have been the easiest way to get the benefits to the most people, regardless of distance from the ocean. (I wonder if there would be any way to test iodine deficiency in bodies in the Alps before, during, and after the Roman Empire…)

Someone get on testing bodies for iodine deficiency!


So, what are you thinking about?

What Mental Traits does the Arctic Select for?

Apropos Friday’s conversation about the transition from hunting to pastoralism and the different strategies hunters employ in different environments, I got to thinking about how these different food-production systems could influence the development of different “intelligences,” or at least mental processes that underlie intelligence.

Ingold explains that in warm climes, hunter-gatherers have many food resources they can exploit, and if one resource starts running low, they can fairly easily switch to another. If there aren’t enough yams around, you can eat melons; if not enough melons, squirrels; if no squirrels, eggs. I recall a study of Australian Aborigines who agreed to go back to hunter-gatherering for a while after living in town for several decades. Among other things (like increased health,) scientists noted that the Aborigines increased the number of different kinds of foods they consumed from, IIRC, about 40 per week to 100.

By contrast, hunters in the arctic are highly dependent on exploiting only a few resources–fish, seals, reindeer, and perhaps a few polar bears and foxes. Ingold claims that there are (were) tribes that depended largely on only a few major hunts of migrating animals (netting hundreds of kills) to supply themselves for the whole year.

If those migrating change their course by even a few miles, it’s easy to see how the hunters could miss the herds entirely and, with no other major species around to exploit, starve over the winter.

Let’s consider temperate agriculture as well: the agriculturalist can store food better than the arctic hunter (seal meat does not do good things in the summer,) but lacks the tropical hunter-gatherer’s flexibility; he must stick to his fields and keep working, day in and day out, for a good nine months in a row. Agricultural work is more flexible than assembly line work, where your every minute is dictated by the needs of the factory, but a farmer can’t just wander away from his crops to go hunt for a months just because he feels like it, nor can he hope to make up for a bad wheat harvest by wandering into his neighbor’s fields and picking their potatoes.

Which got me thinking: clearly different people are going to do better at different systems.

But first, what is intelligence? Obviously we could define it in a variety of ways, but let’s stick to reasonable definitions, eg, the ability to use your brain to achieve success, or the ability to get good grades on your report card.

A variety of mental traits contribute to “intelligence,” such as:

  1. The ability to learn lots of information. Information is really useful, both in life and on tests, and smarter brains tend to be better at storing lots and lots of data.
  2. Flexible thinking. This is the ability to draw connections between different things you’ve learned, to be creative, to think up new ideas, etc.
  3. Some form of Drive, Self Will, or long-term planning–that is, the ability to plan for your future and then push yourself to accomplish your goals. (These might more properly be two different traits, but we’ll keep them together for now.)

Your stereotypical autistic, capable of memorizing large quantities of data but not doing much with them, has trait #1 but not 2 or 3.

Artists and musicians tend to have a lot of trait #2, but not necessarily 1 or 3 (though successful artists obviously have a ton of #3)

And an average kid who’s not that bright but works really hard, puts in extra hours of effort on their homework, does extra credit assignments, etc., has a surfeit of #3 but not much 2 or 1.

Anyway, it seems to me like the tropical hunting/gathering environment, with many different species to exploit, would select for flexible thinking–if one food isn’t working out, look for a different one. This may also apply to people from tropical farming/horticulturalist societies.

By contrast, temperate farming seems more likely to select for planning–you can’t just wander off or try to grow something new in time for winter if your first crop doesn’t work out.

Many people have noted that America’s traditionally tropical population (African Americans) seems to be particularly good at flexible thinking, leading to much innovation in arts and music. They are not as talented, though, at Drive, leading to particularly high highschool dropout rates.

America’s traditionally rice-farming population (Asians,) by contrast, has been noted for over a century for its particularly high drive and ability to plan for the future, but not so much for contributions to the arts. East Asian people are noted for their particularly high IQ/SAT/PISA scores, despite the fact that China lags behind the West in GDP and quality of life terms. (Japan, of course, is a fully developed country.) One potential explanation for this is that the Chinese, while very good at working extremely hard, aren’t as good at flexible thinking that would help spur innovation. (I note that the Japanese seem to do just fine at flexible thinking, but you know, the Japanese aren’t Chinese and Japan isn’t China.)

(I know I’m not really stating anything novel.) But the real question is:

What kind of mental traits might pastoralism, arctic pastoralism, or arctic hunting select for?

Do Chilblains Affect Blacks More than Whites?

toes afflicted with chilblains
toes afflicted with chilblains

While tromping through a blizzard, seeking insight into circum-polar peoples, I discovered a condition called chilblains. The relevant Wikipedia page is rather short:

Chilblains … is a medical condition that occurs when a predisposed individual is exposed to cold and humidity, causing tissue damage. It is often confused with frostbite and trench foot. Damage to capillary beds in the skin causes redness, itching, inflammation, and sometimes blisters. Chilblains can be reduced by keeping the feet and hands warm in cold weather, and avoiding extreme temperature changes. Chilblains can be idiopathic (spontaneous and unrelated to another disease), but may also be a manifestation of another serious medical condition that needs to be investigated.

The part they don’t mention is that it can really hurt.

The first HBD-related question I became interested in–after visiting a black friend’s house and observing that she was comfortable without the AC on, even though it was summer–is whether people from different latitudes prefer different temperatures. It seems pretty obvious: surely people from Yakutsk prefer different temperatures than people from Pakistan. It also seems easy to test: just put people in a room and give them complete control over the thermostat. And yet, I’d never heard anyone discuss the idea.

Anyway, the perfunctory Wikipedia page on chilblains mentioned nothing about racial or ethnic predisposition to the condition–even though surely the Eskimo (Inuit) who have genetic admixture from both ice-age Neanderthals and Denisovans:

“Using this method, they found two regions with a strong signal of selection: (i) one region contains the cluster of FADS genes, involved in the metabolism of unsaturated fatty acids; (ii) the other region contains WARS2 and TBX15, located on chromosome 1.” …

“TBX15 plays a role in the differentiation of brown and brite adipocytes. Brown and brite adipocytes produce heat via lipid oxidation when stimulated by cold temperatures, making TBX15 a strong candidate gene for adaptation to life in the Arctic.” …

“The Inuit DNA sequence in this region matches very well with the Denisovan genome, and it is highly differentiated from other present-day human sequences, though we can’t discard the possibility that the variant was introduced from another archaic group whose genomes we haven’t sampled yet,” Dr. Racimo said.

The scientists found that the variant is present at low-to-intermediate frequencies throughout Eurasia, and at especially high frequencies in the Inuits and Native American populations, but almost absent in Africa.

Sub-Saharan Africans have their own archaic admixture, but they have very little to no ice-age hominin–which is probably good for them, except for those who’ve moved further north.

Imagine my surprised upon searching and discovering very little research on whether chilblains disproportionately affects people of different races or ethnicities. If you were a dermatologist–or a genetically prone person–wouldn’t you want to know?

So here’s what I did find:

The National Athletic Trainers Association Position Statement on Cold Injuries notes:

Black individuals have been shown to be 2 to 4 times more likely than individuals from other racial groups to sustain cold injuries. These differences may be due to cold weather experience, but are likely due to anthropometric and body composition differences, including less-pronounced CIVD, increased sympathetic response to cold exposure, and thinner, longer digits.3,6

I think CIVD=Cold-Induced Vasodilation

The Military Surgeon: Journal of the Association of Military Surgeons of the United States, Volumes 36-37, states:


c2ijvyvveaaehdz c2ijw49vqaajuou

The text continues with descriptions of amputating rotting feet.

A PDF from the UK, titled “Cold Injury,” notes:


Notice that the incidence of chilblains is actually less in extremely cold places than moderately cold places–attributed here to people in these places being well-equipped for the cold.


Finally I found a PDF of a study performed, I believe, by the US Military, Epidemiology of US Army Cold Weather Injuries, 1980-1999:


While I would really prefer to have more ethnic groups included in the study, two will have to suffice. It looks like trench foot may be an equal-opportunity offender, but chilblains, frostbite, and other cold-related injuries attack black men (at least in the army) at about 4x the rate of white men, and black women 2x as often as white women (but women in the army may not endure the same conditions as men in the army.)

On a related note, while researching this post, I came across this historic reference to infectious scurvy and diabetes, in the Journal of Tropical Medicine and Hygiene, Volumes 4-5 (published in 1902):


Note: this is why it is important to discard bad theories after they’ve been disproven. Otherwise, you kill your scurvy victims by quarantining them instead of giving them oranges.

Wed Open Thread: 770,000 genomes and the American Nations

Wow, is it Wednesday already? Time definitely flies when you’re busy.

In interesting news, Politico ran an article with a long (and somewhat misleading) section about Moldbug, and further alleging (based on unnamed “sources” who are probably GodfreyElfwick again*,) that Moldbug is in communication with the Trump Administration:

In one January 2008 post, titled “How I stopped believing in democracy,” he decries the “Georgetownist worldview” of elites like the late diplomat George Kennan. Moldbug’s writings, coming amid the failure of the U.S. state-building project in Iraq, are hard to parse clearly and are open to multiple interpretations, but the author seems aware that his views are provocative. “It’s been a while since I posted anything really controversial and offensive here,” he begins in a July 25, 2007, post explaining why he associates democracy with “war, tyranny, destruction and poverty.”

Moldbug, who does not do interviews and could not be reached for this story, has reportedly opened up a line to the White House, communicating with Bannon and his aides through an intermediary, according to a source. Yarvin said he has never spoken with Bannon.

Vox does a much longer hit piece on Moldbug, just to make sure you understand that they really, truly don’t approve of him, then provides more detail on Moldbug’s denial:

The idea that I’m “communicating” with Steve Bannon through an “intermediary” is preposterous. I have never met Steve Bannon or communicated with him, directly or indirectly. You might as well accuse the Obama administration of being run by a schizophrenic homeless person in Dupont Circle, because he tapes his mimeographed screeds to light poles where Valerie Jarrett can read them.

*In all fairness, there was a comment over on Jim’s Blog to the effect that there is some orthosphere-aligned person in contact with the Trump administration, which may have set off a chain of speculation that ended with someone claiming they had totally legit sources saying Moldbug was in contact with Bannon.

In other news, Han et al have released Clustering of 770,000 genomes reveals post-colonial population structure of North America:

Here we identify very recent fine-scale population structure in North America from a network of over 500 million genetic (identity-by-descent, IBD) connections among 770,000 genotyped individuals of US origin. We detect densely connected clusters within the network and annotate these clusters using a database of over 20 million genealogical records. Recent population patterns captured by IBD clustering include immigrants such as Scandinavians and French Canadians; groups with continental admixture such as Puerto Ricans; settlers such as the Amish and Appalachians who experienced geographic or cultural isolation; and broad historical trends, including reduced north-south gene flow. Our results yield a detailed historical portrait of North America after European settlement and support substantial genetic heterogeneity in the United States beyond that uncovered by previous studies.

Wow! (I am tempted to add “just wow.”) They have created a couple of amazing maps:


Comment of the Week goes to Tim Smithers for his contributions on IQ in Are the Pygmies Retarded:

IQ generally measures the ability to learn, retain information, and make logical decisions and conclusions. It is not about mathematics nor reading, at least in modern testing (since about 1980).
Modern IQ tests typically do not have any math or even reading. Many have no verbiage at all, and there is no knowledge of math required in the least.
For example, a non-verbal, non-math IQ test may have a question that shows arrows pointing in different directions. The test taker must identify which direction would make the most sense for the next arrow to go.
I’m very sorry to disappoint, but I’ve done considerable research into IQ testing over the past decade. The tests have had cultural biases removed (including the assumption that one can read) in order to assess a persons ability to learn, to retain information, and to use common logic. …

You may, of course, RTWT there.

So, how’s it going out there?


Race: The Social Construction of a Biological Reality, pt 2

Note: This post still contains a lot of oversimplification for the sake of explaining a few things.

Welcome back to our discussion of the geographic dispersion of humanity. On Tuesday, we discussed how two great barriers–the Sahara desert and the Himalayas + central Asian desert–have impeded human travelers over the millennia, resulting in three large, fairly well-defined groups of humans, the major races: Sub-Saharan Africans (SSA), Caucasians, and east Asians.

Of course, any astute motorist, having come to a halt at the Asian end of our highway, might observe that there is, in fact, a great deal of land in the world that we have not yet explored. So we head to the local shop and pick up a better map:


Our new map shows us navigational directions for getting to Melanesia and Australia–in ice age times, it instructs us, we can drive most of the way. If there isn’t an ice age, we’ll have to take a boat.

900px-oceania_un_geoscheme_-_map_of_melanesia-svgThe people of Melanesia and Australia are related, the descendants of one of the first groups of humans to split off from the greater tribe that left Africa some 70k ago.

As the name “Melanesian” implies, they are quite dark-skinned–a result of never having ventured far from the equatorial zone.

Today, they live in eastern Indonesia, Papua New Guinea, Australia, and a smattering of smaller islands. (Notably, the Maori of New Zealand are Polynesians like the Hawaiians, not Melanesians, descendants of a different migration wave that originated in Taiwan.)

Fijian mountain warrior
Fijian mountain warrior with curly, “African” style hair

There is some speculation that they might have once been wider-spread than they currently are, or that various south-Asian tribes might be related to them, (eg, “A 2009 genetic study in India found similarities among Indian archaic populations and Aboriginal people, indicating a Southern migration route, with expanding populations from Southeast Asia migrating to Indonesia and Australia,”) but I don’t think any mainland group would today be classed as majority Melanesian by DNA.

They may also be related to the scattered tribes of similarly dark-skinned, diminutive people known as the Negritos:

Males from the Aeta people (or Agta) people of The Philippines, are of great interest to genetic, anthropological and historical researchers, as at least 83% of them belong to haplogroup K2b, in the form of its rare primary clades K2b1* and P* (a.k.a. K2b2* or P-P295*).[7] Most Aeta males (60%) carry K-P397 (K2b1), which is otherwise uncommon in the Philippines and is strongly associated with the indigenous peoples of Melanesia and Micronesia. Basal P* is rare outside the Aeta and some other groups within Maritime South East Asia. …

Naural blond hair
Two Melanesian girls from Vanatu (blond hair is common in Melanesian children.)

A 2010 study by the Anthropological Survey of India and the Texas-based Southwest Foundation for Biomedical Research identified seven genomes from 26 isolated “relic tribes” from the Indian mainland, such as the Baiga, which share “two synonymous polymorphisms with the M42 haplogroup, which is specific to Australian Aborigines“. These were specific mtDNA mutations that are shared exclusively by Australian aborigines and these Indian tribes, and no other known human groupings.[12]

A study of blood groups and proteins in the 1950s suggested that the Andamanese were more closely related to Oceanic peoples than African Pygmies. Genetic studies on Philippine Negritos, based on polymorphic blood enzymes and antigens, showed they were similar to surrounding Asian populations.[13]

Negrito peoples may descend from Australoid Melanesian settlers of Southeast Asia. Despite being isolated, the different peoples do share genetic similarities with their neighboring populations.[13][14] They also show relevant phenotypic (anatomic) variations which require explanation.[14]

In contrast, a recent genetic study found that unlike other early groups in Malesia, Andamanese Negritos lack the Denisovan hominin admixture in their DNA. Denisovan ancestry is found among indigenous Melanesian and Australian populations between 4–6%.[15][16]

Australian Aboriginal man
Australian Aboriginal man

However, the Negritos are a very small set of tribes, and I am not confident that they are even significantly related to each other, rather than just some short folks living on a few scattered islands. We must leave them for another day.

The vast majority of Aborigines and Melanesians live in Australia, Papua New Guinea, and nearby islands. They resemble Africans, because they split off from the rest of the out-of-Africa crew long before the traits we now associate with “whites” and “Asians” evolved, and have since stayed near the equator, but they are most closely related to–sharing DNA with–south Asians (and Indians.)

So we have, here, on the genetic level, a funny situation. Melanesians are–relatively speaking–a small group. According to Wikipedia, thee are about 12 million Melanesians and 606,000 Aborigines. By contrast, Tokyo prefecture has 13 million people and the total Tokyo metro area has nearly 38 million. Meanwhile, the Han Chinese–not a race but a single, fairly homogenous ethnic group–number around 1.3 billion.

Of all the world’s peoples, Melanesians/Aborigines are most closely related to other Asians–but this is a distant relationship, and those same Asians are more closely related to Caucasians than to Aborigines.

As I mentioned on Tuesday, the diagram, because it is 1-dimensional, can only show the distance between two groups at a time, not all groups. The genetic distance between Caucasians and Aborigines is about 60 or 50k, while the distance between Asians and Caucasians is around 40k, but the distance between Sub-Saharan Africans and ALL non-SSAs is about 70k, whether they’re in Australia, Patagonia, or France. Our map is not designed to show this distance, only the distances between individual pairs.

Some anthropologists refer to Bushmen as "gracile," which means they are a little shorter than average Europeans and not stockily built
Some anthropologists refer to Bushmen as “gracile,” which means they are a little shorter than average Europeans and not stockily built

Now if we hopped back in our car and zoomed back to the beginning of our trip, pausing to refuel in Lagos, we’d note another small group that has been added to the other end of the map: the Bushmen, aka the Khoi-San people. Wikipedia estimates 90,000 San and doesn’t give an estimate for the Khoi people, but their largest group, the Nama, has about 200,000 people. We’ll estimate the total, therefore, around 500,000 people, just to be safe.

The Bushmen are famous for being among the world’s last hunter-gatherers; their cousins the Khoi people are pastoralists. There were undoubtedly more of them in the past, before both Europeans and Bantus arrived in southern Africa. Some people think Bushmen look a little Asian, due to their lighter complexions than their more equatorial African cousins.


Various Y chromosome studies show that the San carry some of the most divergent (oldest) human Y-chromosome haplogroups. These haplogroups are specific sub-groups of haplogroups A and B, the two earliest branches on the human Y-chromosome tree.[48][49][50]

Mitochondrial DNA studies also provide evidence that the San carry high frequencies of the earliest haplogroup branches in the human mitochondrial DNA tree. This DNA is inherited only from one’s mother. The most divergent (oldest) mitochondrial haplogroup, L0d, has been identified at its highest frequencies in the southern African San groups.[48][51][52][53]

I loved that movie
The late Nǃxau ǂToma, (aka Gcao Tekene Coma,) Bushman star of “The Gods Must be Crazy,” roughly 1944-2003

In a study published in March 2011, Brenna Henn and colleagues found that the ǂKhomani San, as well as the Sandawe and Hadza peoples of Tanzania, were the most genetically diverse of any living humans studied. This high degree of genetic diversity hints at the origin of anatomically modern humans.[54][55]

Recent analysis suggests that the San may have been isolated from other original ancestral groups for as much as 100,000 years and later rejoined, re-integrating the human gene pool.[56]

A DNA study of fully sequenced genomes, published in September 2016, showed that the ancestors of today’s San hunter-gatherers began to diverge from other human populations in Africa about 200,000 years ago and were fully isolated by 100,000 years ago … [57]

So the total distance between Nigerians and Australian Aborogines is 70k years; the distance between Nigerians and Bushmen is at least 100k years.

When we zoom in on the big three–Sub-Saharan Africans, Caucasians, and Asians–they clade quite easily and obviously into three races. But when we add Aborigines and Bushmen, things complicate. Should we have a “race” smaller than the average American city? Or should we just lump them in with their nearest neighbors–Bushmen with Bantus and Aborigines with Asians?

I am fine with doing both, actually–but wait, I’m not done complicating matters! Tune in on Monday for more.