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.
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.
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…
…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.
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.
The Negritos are a fascinating group of short-statured, dark-skinned, frizzy-haired peoples from southeast Asia–chiefly the Andaman Islands, Malaysia, Philippines, and Thailand. (Spelling note: “Negritoes” is also an acceptable plural, and some sources use the Spanish Negrillos.)
Because of their appearance, they have long been associated with African peoples, especially the Pygmies. Pygmies are formally defined as any group where adult men are, on average 4’11” or less and is almost always used specifically to refer to African Pygmies; the term pygmoid is sometimes used for groups whose men average 5’1″ or below, including the Negritos. (Some of the Bushmen tribes, Bolivians, Amazonians, the remote Taron, and a variety of others may also be pygmoid, by this definition.)
However, genetic testing has long indicated that they, along with other Melanesians and Australian Aborigines, are more closely related to other east Asian peoples than any African groups. In other words, they’re part of the greater Asian race, albeit a distant branch of it.
But how distant? And are the various Negrito groups closely related to each other, or do there just happen to be a variety of short groups of people in the area, perhaps due to convergent evolution triggered by insular dwarfism?
They found that the Negrito groups they studied “are basal to other East and Southeast Asians,” (basal: forming the bottom layer or base. In this case, it means they split off first,) “and that they diverged from West Eurasians at least 38,000 years ago.” (West Eurasians: Caucasians, consisting of Europeans, Middle Easterners, North Africans, and people from India.) “We also found relatively high traces of Denisovan admixture in the Philippine Negritos, but not in the Malaysian and Andamanese groups.” (Denisovans are a group of extinct humans similar to Neanderthals, but we’ve yet to find many of their bones. Just as Neanderthal DNA shows up in non-Sub-Saharan-Africans, so Denisvoan shows up in Melanesians.)
Figure 1 (A) shows PC analysis of Andamanese, Malaysian, and Philippine Negritos, revealing three distinct clusters:
In the upper right-hand corner, the Aeta, Agta, Batak, and Mamanwa are Philippine Negritos. The Manobo are non-Negrito Filipinos.
In the lower right-hand corner are the Jehai, Kintak and Batek are Malaysian Negritos.
And in the upper left, we have the extremely isolated Andamanese Onge and Jarawa Negritos.
(Phil-NN and Mly-NN I believe are Filipino and Malaysian Non-Negritos.)
You can find the same chart, but flipped upside down, with Papuan and Melanesian DNA in the supplemental materials. Of the three groups, they cluster closest to the Philippine Negritos, along the same line with the Malaysians.
By excluding the Andamanese (and Kintak) Negritos, Figure 1 (B) allows a closer look at the structure of the Philippine Negritos.
The Agta, Aeta, and Batak form a horizontal “comet-like pattern,” which likely indicates admixture with non-Negrito Philipine groups like the Manobo. The Mamanawa, who hail from a different part of the Philippines, also show this comet-like patterns, but along a different axis–likely because they intermixed with the different Filipinos who lived in their area. As you can see, there’s a fair amount of overlap–several of the Manobo individuals clustered with the Mamanwa Negritos, and the Batak cluster near several non-Negrito groups (see supplemental chart S4 B)–suggesting high amounts of mixing between these groups.
ADMIXTURE analysis reveals a similar picture. The non-Negrito Filipino groups show up primarily as Orange. The Aeta, Agta, and Batak form a clear genetic cluster with each other and cline with the Orange Filipinos, with the Aeta the least admixed and Batak the most.
The white are on the chart isn’t a data error, but the unique signature of the geographically separated Mananwa, who are highly mixed with the Manobo–and the Manobo, in turn, are mixed with them.
But this alone doesn’t tell us how ancient these populations are, nor if they’re descended from one ancestral pop. For this, the authors constructed several phylogenetic trees, based on all of the data at hand and assuming from 0 – 5 admixture events. The one on the left assumes 5 events, but for clarity only shows three of them. The Denisovan DNA is fascinating and well-documented elsewhere in Melanesian populatons; that Malaysian and Philippine Negritos mixed with their neighbors is also known, supporting the choice of this tree as the most likely to be accurate.
Regardless of which you pick, all of the trees show very similar results, with the biggest difference being whether the Melanesians/Papuans split before or after the Andamanese/Malaysian Negritos.
In case you are unfamiliar with these trees, I’ll run down a quick explanation: This is a human family tree, with each split showing where one group of humans split off from the others and became an isolated group with its own unique genetic patterns. The orange and red lines mark places where formerly isolated groups met and interbred, producing children that are a mix of both. The first split in the tree, going back million of years, is between all Homo sapiens (our species) and the Denisovans, a sister species related to the Neanderthals.
All humans outside of sub-Saharan Africans have some Neanderthal DNA because their ancestors met and interbred with Neanderthals on their way Out of Africa. Melanesians, Papuans, and some Negritos also have some Denisovan DNA, because their ancestors met and made children with members of this obscure human species, but Denisovan DNA is quite rare outside these groups.
Here is a map of Denisovan DNA levels the authors found, with 4% of Papuan DNA hailing from Denisivan ancestors, and Aeta nearly as high. By contrast, the Andamanese Negritos appear to have zero Denisovan. Either the Andamanese split off before the ancestors of the Philippine Negritos and Papuans met the Denisovans, or all Denisovan DNA has been purged from their bloodlines, perhaps because it just wasn’t helpful for surviving on their islands.
Back to the Tree: The second node is where the Biaka, a group of Pygmies from the Congo Rainforest in central Africa. Pygmy lineages are among the most ancient on earth, potentially going back over 200,000 years, well before any Homo sapiens had left Africa.
The next group that splits off from the rest of humanity are the Yoruba, a single ethnic group chosen to stand in for the entirety of the Bantus. Bantus are the group that you most likely think of when you think of black Africans, because over the past three millennia they have expanded greatly and conquered most of sub-Saharan Africa.
Next we have the Out of Africa event and the split between Caucasians (here represented by the French) and the greater Asian clade, which includes Australian Aborigines, Melanesians, Polynesians, Chinese, Japanese, Siberians, Inuit, and Native Americans.
The first groups to split off from the greater Asian clade (aka race) were the Andamanese and Malaysian Negritos, followed by the Papuans/Melanesians Australian Aborigines are closely related to Papuans, as Australia and Papua New Guinea were connected in a single continent (called Sahul) back during the last Ice Age. Most of Indonesia and parts of the Philippines were also connected into a single landmass, called Sunda. Sensibly, people reached Sunda before Sahul, though (Perhaps at that time the Andaman islands, to the northwest of Sumatra, were also connected or at least closer to the mainland.)
Irrespective of the exact order in which Melanesians and individual Negrito groups split off, they all split well before all of the other Asian groups in the area.
This is supported by legends told by the Filipinos themselves:
Legends, such as those involving the Ten Bornean Datus and the Binirayan Festival, tell tales about how, at the beginning of the 12th century when Indonesia and Philippines were under the rule of Indianized native kingdoms, the ancestors of the Bisaya escaped from Borneo from the persecution of Rajah Makatunaw. Led by Datu Puti and Datu Sumakwel and sailing with boats called balangays, they landed near a river called Suaragan, on the southwest coast of Panay, (the place then known as Aninipay), and bartered the land from an Ati [Negrito] headman named Polpolan and his son Marikudo for the price of a necklace and one golden salakot. The hills were left to the Atis while the plains and rivers to the Malays. This meeting is commemorated through the Ati-atihan festival.
The study’s authors estimate that the Negritos split from Europeans (Caucasians) around 30-38,000 years ago, and that the Malaysian and Philippine Negritos split around
13-15,000 years ago. (This all seems a bit tentative, IMO, especially since we have physical evidence of people in the area going back much further than that, and the authors themselves admit in the discussion that their time estimate may be too short.)
The authors also note:
Both our NJ (fig. 3A) and UPGMA (supplementary fig. S10) trees show that after divergence from Europeans, the ancestral Asians subsequently split into Papuans, Negritos and East Asians, implying a one-wave colonization of Asia. … This is in contrast to the study based on whole genome sequences that suggested Australian Aboriginal/Papuan first split from European/East Asians 60 kya, and later Europeans and East Asians diverged 40 kya (Malaspinas et al. 2016). This implies a two-wave migration into Asia…
The matter is still up for debate/more study.
In conclusion: All of the Negrito groups are likely descended from a common ancestor, (rather than having evolved from separate groups that happened to develop similar body types due to exposure to similar environments,) and were among the very first inhabitants of their regions. Despite their short stature, they are more closely related to other Asian groups (like the Chinese) than to African Pygmies. Significant mixing with their neighbors, however, is quickly obscuring their ancient lineages.
I wonder if all ancient human groups were originally short, and height a recently evolved trait in some groups?
In closing, I’d like to thank Jinam et al for their hard work in writing this article and making it available to the public, their sponsors, and the unique Negrito peoples themselves for surviving so long.
A species may live in relative equilibrium with its environment, hardly changing from generation to generation, for millions of years. Turtles, for example, have barely changed since the Cretaceous, when dinosaurs still roamed the Earth.
But if the environment changes–critically, if selective pressures change–then the species will change, too. This was most famously demonstrated with English moths, which changed color from white-and-black speckled to pure black when pollution darkened the trunks of the trees they lived on. To survive, these moths need to avoid being eaten by birds, so any moth that stands out against the tree trunks tends to get turned into an avian snack. Against light-colored trees, dark-colored moths stood out and were eaten. Against dark-colored trees, light-colored moths stand out.
This change did not require millions of years. Dark-colored moths were virtually unknown in 1810, but by 1895, 98% of the moths were black.
The time it takes for evolution to occur depends simply on A. The frequency of a trait in the population and B. How strongly you are selecting for (or against) it.
Let’s break this down a little bit. Within a species, there exists a great deal of genetic variation. Some of this variation happens because two parents with different genes get together and produce offspring with a combination of their genes. Some of this variation happens because of random errors–mutations–that occur during copying of the genetic code. Much of the “natural variation” we see today started as some kind of error that proved to be useful, or at least not harmful. For example, all humans originally had dark skin similar to modern Africans’, but random mutations in some of the folks who no longer lived in Africa gave them lighter skin, eventually producing “white” and “Asian” skin tones.
(These random mutations also happen in Africa, but there they are harmful and so don’t stick around.)
Natural selection can only act on the traits that are actually present in the population. If we tried to select for “ability to shoot x-ray lasers from our eyes,” we wouldn’t get very far, because no one actually has that mutation. By contrast, albinism is rare, but it definitely exists, and if for some reason we wanted to select for it, we certainly could. (The incidence of albinism among the Hopi Indians is high enough–1 in 200 Hopis vs. 1 in 20,000 Europeans generally and 1 in 30,000 Southern Europeans–for scientists to discuss whether the Hopi have been actively selecting for albinism. This still isn’t a lot of albinism, but since the American Southwest is not a good environment for pale skin, it’s something.)
You will have a much easier time selecting for traits that crop up more frequently in your population than traits that crop up rarely (or never).
Second, we have intensity–and variety–of selective pressure. What % of your population is getting removed by natural selection each year? If 50% of your moths get eaten by birds because they’re too light, you’ll get a much faster change than if only 10% of moths get eaten.
Selection doesn’t have to involve getting eaten, though. Perhaps some of your moths are moth Lotharios, seducing all of the moth ladies with their fuzzy antennae. Over time, the moth population will develop fuzzier antennae as these handsome males out-reproduce their less hirsute cousins.
No matter what kind of selection you have, nor what part of your curve it’s working on, all that ultimately matters is how many offspring each individual has. If white moths have more children than black moths, then you end up with more white moths. If black moths have more babies, then you get more black moths.
So what happens when you completely remove selective pressures from a population?
Back in 1968, ethologist John B. Calhoun set up an experiment popularly called “Mouse Utopia.” Four pairs of mice were given a large, comfortable habitat with no predators and plenty of food and water.
Predictably, the mouse population increased rapidly–once the mice were established in their new homes, their population doubled every 55 days. But after 211 days of explosive growth, reproduction began–mysteriously–to slow. For the next 245 days, the mouse population doubled only once every 145 days.
The birth rate continued to decline. As births and death reached parity, the mouse population stopped growing. Finally the last breeding female died, and the whole colony went extinct.
As I’ve mentioned before Israel is (AFAIK) the only developed country in the world with a TFR above replacement.
It has long been known that overcrowding leads to population stress and reduced reproduction, but overcrowding can only explain why the mouse population began to shrink–not why it died out. Surely by the time there were only a few breeding pairs left, things had become comfortable enough for the remaining mice to resume reproducing. Why did the population not stabilize at some comfortable level?
Professor Bruce Charlton suggests an alternative explanation: the removal of selective pressures on the mouse population resulted in increasing mutational load, until the entire population became too mutated to reproduce.
Unfortunately, randomly changing part of your genetic code is more likely to give you no skin than skintanium armor.
But only the worst genetic problems that never see the light of day. Plenty of mutations merely reduce fitness without actually killing you. Down Syndrome, famously, is caused by an extra copy of chromosome 21.
While a few traits–such as sex or eye color–can be simply modeled as influenced by only one or two genes, many traits–such as height or IQ–appear to be influenced by hundreds or thousands of genes:
Differences in human height is 60–80% heritable, according to several twin studies and has been considered polygenic since the Mendelian-biometrician debate a hundred years ago. A genome-wide association (GWA) study of more than 180,000 individuals has identified hundreds of genetic variants in at least 180 loci associated with adult human height. The number of individuals has since been expanded to 253,288 individuals and the number of genetic variants identified is 697 in 423 genetic loci.
Obviously most of these genes each plays only a small role in determining overall height (and this is of course holding environmental factors constant.) There are a few extreme conditions–gigantism and dwarfism–that are caused by single mutations, but the vast majority of height variation is caused by which particular mix of those 700 or so variants you happen to have.
The general figure for the heritability of IQ, according to an authoritative American Psychological Association report, is 0.45 for children, and rises to around 0.75 for late teens and adults. In simpler terms, IQ goes from being weakly correlated with genetics, for children, to being strongly correlated with genetics for late teens and adults. … Recent studies suggest that family and parenting characteristics are not significant contributors to variation in IQ scores; however, poor prenatal environment, malnutrition and disease can have deleterious effects.…
Despite intelligence having substantial heritability2 (0.54) and a confirmed polygenic nature, initial genetic studies were mostly underpowered3, 4, 5. Here we report a meta-analysis for intelligence of 78,308 individuals. We identify 336 associated SNPs (METAL P < 5 × 10−8) in 18 genomic loci, of which 15 are new. Around half of the SNPs are located inside a gene, implicating 22 genes, of which 11 are new findings. Gene-based analyses identified an additional 30 genes (MAGMA P < 2.73 × 10−6), of which all but one had not been implicated previously. We show that the identified genes are predominantly expressed in brain tissue, and pathway analysis indicates the involvement of genes regulating cell development (MAGMA competitive P = 3.5 × 10−6). Despite the well-known difference in twin-based heritability2 for intelligence in childhood (0.45) and adulthood (0.80), we show substantial genetic correlation (rg = 0.89, LD score regression P = 5.4 × 10−29). These findings provide new insight into the genetic architecture of intelligence.
The greater number of genes influence a trait, the harder they are to identify without extremely large studies, because any small group of people might not even have the same set of relevant genes.
High IQ correlates positively with a number of life outcomes, like health and longevity, while low IQ correlates with negative outcomes like disease, mental illness, and early death. Obviously this is in part because dumb people are more likely to make dumb choices which lead to death or disease, but IQ also correlates with choice-free matters like height and your ability to quickly press a button. Our brains are not some mysterious entities floating in a void, but physical parts of our bodies, and anything that affects our overall health and physical functioning is likely to also have an effect on our brains.
The study focused, for the first time, on rare, functional SNPs – rare because previous research had only considered common SNPs and functional because these are SNPs that are likely to cause differences in the creation of proteins.
The researchers did not find any individual protein-altering SNPs that met strict criteria for differences between the high-intelligence group and the control group. However, for SNPs that showed some difference between the groups, the rare allele was less frequently observed in the high intelligence group. This observation is consistent with research indicating that rare functional alleles are more often detrimental than beneficial to intelligence.
Greg Cochran has some interesting Thoughts on Genetic Load. (Currently, the most interesting candidate genes for potentially increasing IQ also have terrible side effects, like autism, Tay Sachs and Torsion Dystonia. The idea is that–perhaps–if you have only a few genes related to the condition, you get an IQ boost, but if you have too many, you get screwed.) Of course, even conventional high-IQ has a cost: increased maternal mortality (larger heads).
the difference between the fitness of an average genotype in a population and the fitness of some reference genotype, which may be either the best present in a population, or may be the theoretically optimal genotype. … Deleterious mutation load is the main contributing factor to genetic load overall. Most mutations are deleterious, and occur at a high rate.
There’s math, if you want it.
Normally, genetic mutations are removed from the population at a rate determined by how bad they are. Really bad mutations kill you instantly, and so are never born. Slightly less bad mutations might survive, but never reproduce. Mutations that are only a little bit deleterious might have no obvious effect, but result in having slightly fewer children than your neighbors. Over many generations, this mutation will eventually disappear.
(Some mutations are more complicated–sickle cell, for example, is protective against malaria if you have only one copy of the mutation, but gives you sickle cell anemia if you have two.)
Throughout history, infant mortality was our single biggest killer. For example, here is some data from Jakubany, a town in the Carpathian Mountains:
We can see that, prior to the 1900s, the town’s infant mortality rate stayed consistently above 20%, and often peaked near 80%.
When I first ran a calculation of the infant mortality rate, I could not believe certain of the intermediate results. I recompiled all of the data and recalculated … with the same astounding result – 50.4% of the children born in Jakubany between the years 1772 and 1890 would diebefore reaching ten years of age! …one out of every two! Further, over the same 118 year period, of the 13306 children who were born, 2958 died (~22 %) before reaching the age of one.
Historical infant mortality rates can be difficult to calculate in part because they were so high, people didn’t always bother to record infant deaths. And since infants are small and their bones delicate, their burials are not as easy to find as adults’. Nevertheless, Wikipedia estimates that Paleolithic man had an average life expectancy of 33 years:
Based on the data from recent hunter-gatherer populations, it is estimated that at 15, life expectancy was an additional 39 years (total 54), with a 0.60 probability of reaching 15.
In other words, a 40% chance of dying in childhood. (Not exactly the same as infant mortality, but close.)
Wikipedia gives similarly dismal stats for life expectancy in the Neolithic (20-33), Bronze and Iron ages (26), Classical Greece(28 or 25), Classical Rome (20-30), Pre-Columbian Southwest US (25-30), Medieval Islamic Caliphate (35), Late Medieval English Peerage (30), early modern England (33-40), and the whole world in 1900 (31).
Over at ThoughtCo: Surviving Infancy in the Middle Ages, the author reports estimates for between 30 and 50% infant mortality rates. I recall a study on Anasazi nutrition which I sadly can’t locate right now, which found 100% malnutrition rates among adults (based on enamel hypoplasias,) and 50% infant mortality.
As Priceonomics notes, the main driver of increasing global life expectancy–48 years in 1950 and 71.5 years in 2014 (according to Wikipedia)–has been a massive decrease in infant mortality. The average life expectancy of an American newborn back in 1900 was only 47 and a half years, whereas a 60 year old could expect to live to be 75. In 1998, the average infant could expect to live to about 75, and the average 60 year old could expect to live to about 80.
Michael A Woodley suggests that what was going on [in the Mouse experiment] was much more likely to be mutation accumulation; with deleterious (but non-fatal) genes incrementally accumulating with each generation and generating a wide range of increasingly maladaptive behavioural pathologies; this process rapidly overwhelming and destroying the population before any beneficial mutations could emerge to ‘save; the colony from extinction. …
The reason why mouse utopia might produce so rapid and extreme a mutation accumulation is that wild mice naturally suffer very high mortality rates from predation. …
Thus mutation selection balance is in operation among wild mice, with very high mortality rates continually weeding-out the high rate of spontaneously-occurring new mutations (especially among males) – with typically only a small and relatively mutation-free proportion of the (large numbers of) offspring surviving to reproduce; and a minority of the most active and healthy (mutation free) males siring the bulk of each generation.
However, in Mouse Utopia, there is no predation and all the other causes of mortality (eg. Starvation, violence from other mice) are reduced to a minimum – so the frequent mutations just accumulate, generation upon generation – randomly producing all sorts of pathological (maladaptive) behaviours.
Today, almost everyone in the developed world has plenty of food, a comfortable home, and doesn’t have to worry about dying of bubonic plague. We live in humantopia, where the biggest factor influencing how many kids you have is how many you want to have.
Back in 1930, infant mortality rates were highest among the children of unskilled manual laborers, and lowest among the children of professionals (IIRC, this is Brittish data.) Today, infant mortality is almost non-existent, but voluntary childlessness has now inverted this phenomena:
Yes, the percent of childless women appears to have declined since 1994, but the overall pattern of who is having children still holds. Further, while only 8% of women with post graduate degrees have 4 or more children, 26% of those who never graduated from highschool have 4+ kids. Meanwhile, the age of first-time moms has continued to climb.
Take a moment to consider the high-infant mortality situation: an average couple has a dozen children. Four of them, by random good luck, inherit a good combination of the couple’s genes and turn out healthy and smart. Four, by random bad luck, get a less lucky combination of genes and turn out not particularly healthy or smart. And four, by very bad luck, get some unpleasant mutations that render them quite unhealthy and rather dull.
Infant mortality claims half their children, taking the least healthy. They are left with 4 bright children and 2 moderately intelligent children. The three brightest children succeed at life, marry well, and end up with several healthy, surviving children of their own, while the moderately intelligent do okay and end up with a couple of children.
On average, society’s overall health and IQ should hold steady or even increase over time, depending on how strong the selective pressures actually are.
Or consider a consanguineous couple with a high risk of genetic birth defects: perhaps a full 80% of their children die, but 20% turn out healthy and survive.
Today, by contrast, your average couple has two children. One of them is lucky, healthy, and smart. The other is unlucky, unhealthy, and dumb. Both survive. The lucky kid goes to college, majors in underwater intersectionist basket-weaving, and has one kid at age 40. That kid has Down Syndrome and never reproduces. The unlucky kid can’t keep a job, has chronic health problems, and 3 children by three different partners.
Your consanguineous couple migrates from war-torn Somalia to Minnesota. They still have 12 kids, but three of them are autistic with IQs below the official retardation threshold. “We never had this back in Somalia,” they cry. “We don’t even have a word for it.”
People normally think of dysgenics as merely “the dumb outbreed the smart,” but genetic load applies to everyone–men and women, smart and dull, black and white, young and especially old–because we all make random transcription errors when copying our DNA.
I could offer a list of signs of increasing genetic load, but there’s no way to avoid cherry-picking trends I already know are happening, like falling sperm counts or rising (diagnosed) autism rates, so I’ll skip that. You may substitute your own list of “obvious signs society is falling apart at the genes” if you so desire.
Nevertheless, the transition from 30% (or greater) infant mortality to almost 0% is amazing, both on a technical level and because it heralds an unprecedented era in human evolution. The selective pressures on today’s people are massively different from those our ancestors faced, simply because our ancestors’ biggest filter was infant mortality. Unless infant mortality acted completely at random–taking the genetically loaded and unloaded alike–or on factors completely irrelevant to load, the elimination of infant mortality must continuously increase the genetic load in the human population. Over time, if that load is not selected out–say, through more people being too unhealthy to reproduce–then we will end up with an increasing population of physically sick, maladjusted, mentally ill, and low-IQ people.
If all of the above is correct, then I see only 4 ways out:
Do nothing: Genetic load increases until the population is non-functional and collapses, resulting in a return of Malthusian conditions, invasion by stronger neighbors, or extinction.
Sterilization or other weeding out of high-load people, coupled with higher fertility by low-load people
Abortion of high load fetuses
#1 sounds unpleasant, and #2 would result in masses of unhappy people. We don’t have the technology for #4, yet. I don’t think the technology is quite there for #2, either, but it’s much closer–we can certainly test for many of the deleterious mutations that we do know of.
The Sino-Tibetan languages, in a few sources also known as Tibeto-Burman or Trans-Himalayan, are a family of more than 400 languages spoken in East Asia, Southeast Asia and South Asia. The family is second only to the Indo-European languages in terms of the number of native speakers. The Sino-Tibetan languages with the most native speakers are the varieties of Chinese (1.3 billion speakers), Burmese (33 million) and the Tibetic languages (8 million). Many Sino-Tibetan languages are spoken by small communities in remote mountain areas and as such are poorly documented.
But the claim that Tibetans and Chinese people are genetically disparate looks more questionable. While the Wikipedia page on Sino-Tibetan claims that, “There is no ethnic unity among the many peoples who speak Sino-Tibetan languages,” in the next two sentences it also claims that, “The most numerous are the Han Chinese, numbering 1.4+ billion(in China alone). The Hui (10 million) also speak Chinese but are officially classified as ethnically distinct by the Chinese government.”
But the Chinese government claiming that a group is an official ethnic group doesn’t make it a genetic group. “Hui” just means Muslim, and Muslims of any genetic background can get lumped into the group. I actually read some articles about the Hui ages ago, and as far as I recall, the category didn’t really exist in any official way prior to the modern PRC declaring that it did for census purposes. Today (or recently) there are some special perks for being an ethnic minority in China, like exceptions to the one-child policy, which lead more people to embrace their “Hui” identity and start thinking about themselves in this pan-Chinese-Muslim way rather than in terms of their local ethnic group, but none of this is genetics.
So right away I am suspicious that this claim is more “these groups see themselves as different” than “they are genetically different.” And I totally agree that Tibetan people and Chinese people are culturally distinct and probably see themselves as different groups.
For genetics, let’s turn back to Haak et al’s representation of global genetics:
Just in case you’re new around here, the part dominated by bright blue is sub-Saharan Africans, the yellow is Asians, and the orange is Caucasians. I’ve made a map to make it easier to visualize the distribution of these groups:
The first thing that jumps out at me is that the groups in the Sino-Tibetan language family do not look all that genetically distinct, at least not on a global scale. They’re more similar than Middle Easterners and Europeans, despite the fact that Anatolian farmers invaded Europe several thousand years ago.
The Wikipedia page on Sino-Tibetan notes:
J. A. Matisoff proposed that the urheimat of the Sino-Tibetan languages was around the upper reaches of the Yangtze, Brahmaputra, Salween, and Mekong. This view is in accordance with the hypothesis that bubonic plague, cholera, and other diseases made the easternmost foothills of the Himalayas between China and India difficult for people outside to migrate in but relatively easily for the indigenous people, who had been adapted to the environment, to migrate out.
The Yangtze, Brahmaputra, Salween and Mekong rivers, as you might have already realized if you took a good look at the map at the beginning of the post, all begin in Tibet.
Since Tibet was recently conquered by China, I was initially thinking that perhaps an ancient Chinese group had imposed their language on the Tibetans some time in the remote past, but Tibetans heading downstream and possibly conquering the people below makes a lot more sense.
According to About World Languages, Proto-Sino-Tibetan may have split into its Tibeto- and Sinitic- branches about 4,000 BC. This is about the same time Proto-Indo-European started splitting up, so we have some idea of what a language family looks like when it’s that old; much older, and the languages start becoming so distinct that reconstruction becomes more difficult.
But if we look at the available genetic data a little more closely, we see that there are some major differences between Tibetans and their Sinitic neighbors–most notably, many Tibetan men belong to Y-Chromosome haplogroup D, while most Han Chinese men belong to haplogroup O with a smattering of Haplogroup C, which may have arrived via the Mongols.
The distribution of Haplogroup D-M174 is found among nearly all the populations of Central Asia and Northeast Asia south of the Russian border, although generally at a low frequency of 2% or less. A dramatic spike in the frequency of D-M174 occurs as one approaches the Tibetan Plateau. D-M174 is also found at high frequencies among Japanese people, but it fades into low frequencies in Korea and China proper between Japan and Tibet.
It is found today at high frequency among populations in Tibet, the Japanese archipelago, and the Andaman Islands, though curiously not in India. The Ainu of Japan are notable for possessing almost exclusively Haplogroup D-M174 chromosomes, although Haplogroup C-M217 chromosomes also have been found in 15% (3/20) of sampled Ainu males. Haplogroup D-M174 chromosomes are also found at low to moderate frequencies among populations of Central Asia and northern East Asia as well as the Han and Miao–Yao peoples of China and among several minority populations of Sichuan and Yunnan that speak Tibeto-Burman languages and reside in close proximity to the Tibetans.
Unlike haplogroup C-M217, Haplogroup D-M174 is not found in the New World…
Haplogroup D-M174 is also remarkable for its rather extreme geographic differentiation, with a distinct subset of Haplogroup D-M174 chromosomes being found exclusively in each of the populations that contains a large percentage of individuals whose Y-chromosomes belong to Haplogroup D-M174: Haplogroup D-M15 among the Tibetans (as well as among the mainland East Asian populations that display very low frequencies of Haplogroup D-M174 Y-chromosomes), Haplogroup D-M55 among the various populations of the Japanese Archipelago, Haplogroup D-P99 among the inhabitants of Tibet, Tajikistan and other parts of mountainous southern Central Asia, and paragroup D-M174 without tested positive subclades (probably another monophyletic branch of Haplogroup D) among the Andaman Islanders. Another type (or types) of paragroup D-M174 without tested positive subclades is found at a very low frequency among the Turkic and Mongolic populations of Central Asia, amounting to no more than 1% in total. This apparently ancient diversification of Haplogroup D-M174 suggests that it may perhaps be better characterized as a “super-haplogroup” or “macro-haplogroup.” In one study, the frequency of Haplogroup D-M174 without tested positive subclades found among Thais was 10%.
Haplogroup D’s sister clade, Haplogroup E, (both D and E are descended from Haplogroup DE), is found almost exclusively in Africa.
Haplogroup D is therefore very ancient, estimated at 50-60,000 years old. Haplogroup O, by contrast, is only about 30,000 years old.
On the subject of Han genetics, Wikipedia states:
Y-chromosome haplogroup O3 is a common DNA marker in Han Chinese, as it appeared in China in prehistoric times. It is found in more than 50% of Chinese males, and ranging up to over 80% in certain regional subgroups of the Han ethnicity. However, the mitochondrial DNA (mtDNA) of Han Chinese increases in diversity as one looks from northern to southern China, which suggests that male migrants from northern China married with women from local peoples after arriving in modern-day Guangdong, Fujian, and other regions of southern China. … Another study puts Han Chinese into two groups: northern and southern Han Chinese, and it finds that the genetic characteristics of present-day northern Han Chinese was already formed as early as three-thousand years ago in the Central Plain area.
(Note that 3,000 years ago is potentially a thousand years after the first expansion of Proto-Sino-Tibetan.)
The estimated contribution of northern Hans to southern Hans is substantial in both paternal and maternal lineages and a geographic cline exists for mtDNA. As a result, the northern Hans are the primary contributors to the gene pool of the southern Hans. However, it is noteworthy that the expansion process was dominated by males, as is shown by a greater contribution to the Y-chromosome than the mtDNA from northern Hans to southern Hans. These genetic observations are in line with historical records of continuous and large migratory waves of northern China inhabitants escaping warfare and famine, to southern China.
Interestingly, the page on Tibetans notes, ” It is thought that most of the Tibeto-Burman-speakers in Southwest China, including the Tibetans, are direct descendants from the ancient Qiang.”
This ancient tribe is said to be the progenitor of both the modern Qiang and the Tibetan people. There are still many ethnological and linguistic links between the Qiang and the Tibetans. The Qiang tribe expanded eastward and joined the Han people in the course of historical development, while the other branch that traveled southwards, crosses over the Hengduan Mountains, and entered the Yungui Plateau; some went even farther, to Burma, forming numerous ethnic groups of the Tibetan-Burmese language family. Even today, from linguistic similarities, their relative relationship can be seen.
So here’s what I think happened (keeping in mind that I am in no way an expert on these subjects):
About 8,000 years ago: neolithic people lived in Asia. (People of some sort have been living in Asia since Homo erectus, after all.) The ancestors of today’s Sino-Tibetans lived atop the Tibetan plateau.
About 6,000 years ago: the Tibetans headed downstream, following the course of local rivers. In the process, the probably conquered and absorbed many of the local tribes they encountered.
About 4,000 years ago: the Han and Qiang are ethnically and linguistically distinct, though the Qiang are still fairly similar to the Tibetans.
The rest of Chinese history: Invasion from the north. Not only did the Mongols invade and kill somewhere between 20 and 60 million Chinese people in the 13th century, but there were also multiple of invasions/migrations by people who were trying to get away from the Mongols.
Note that while the original proto-Sino-Tibetan invasion likely spread Tibetan Y-Chromosomes throughout southern China, the later Mongol and other Chinese invasions likely wiped out a large percent of those same chromosomes, as invaders both tend to be men and to kill men; women are more likely to survive invasions.
Most recently, of course, the People’s Republic of China conquered Tibet in 1951.
I’m sure there’s a lot I’m missing that would be obvious to an expert.
Continuing with our discussion of German/Polish history/languages/genetics, let’s look at what some actual geneticists have to say.
(If you’re joining us for the first time, the previous two posts summarize to: due to being next door to each other and having been invaded/settled over the millennia by groups which didn’t really care about modern political borders, Polish and German DNA are quite similar. More recent events, however, like Germany invading Poland and trying to kill all of the Poles and ethnic Germans subsequently fleeing/being expelled from Poland at the end of the war have created conditions necessary for genetic differentiation in the two populations.)
So I’ve been looking up whatever papers I can find on the subject.
The male genetic landscape of the European continent has been shown to be clinal and influenced primarily by geography rather than by language.1 One of the most outstanding phenomena in the Y-chromosomal diversity in Europe concerns the population of Poland, which reveals geographic homogeneity of Y-chromosomal lineages in spite of a relatively large geographic area seized by the Polish state.2 Moreover, a sharp genetic border has been identified between paternal lineages of neighbouring Poland and Germany, which strictly follows a political border between the two countries.3 Massive human resettlements during and shortly after the World War II (WWII), involving millions of Poles and Germans, have been proposed as an explanation for the observed phenomena.2, 3 Thus, it was possible that the local Polish populations formed after the early Slavic migrations displayed genetic heterogeneity before the war owing to genetic drift and/or gene flow with neighbouring populations. It has been also suggested that the revealed homogeneity of Polish paternal lineages existed already before the war owing to a common genetic substrate inherited from the ancestral Slavic population after the Slavs’ early medieval expansion in Europe.2 …
We used high-resolution typing of Y-chromosomal binary and microsatellite markers first to test for male genetic structure in the Polish population before massive human resettlements in the mid-20th century, and second to verify if the observed present-day genetic differentiation between the Polish and German paternal lineages is a direct consequence of the WWII or it has rather resulted from a genetic barrier between peoples with distinct linguistic backgrounds. The study further focuses on providing an answer to the origin of the expansion of the Slavic language in early medieval Europe. For the purpose of our investigation, we have sampled three pre-WWII Polish regional populations, three modern German populations (including the Slavic-speaking Sorbs) and a modern population of Slovakia. …
AMOVA in the studied populations revealed statistically significant support for two linguistically defined groups of populations in both haplogroup and haplotype distributions (Table 2). It also detected statistically significant genetic differentiation for both haplogroups and haplotypes in three Polish pre-WWII regional populations (Table 2). The AMOVA revealed small but statistically significant genetic differentiation between the Polish pre-war and modern populations (Table 2). When both groups of populations were tested for genetic structure separately, only the modern Polish regional samples showed genetic homogeneity (Table 2). Regional differentiation of 10-STR haplotypes in the pre-WWII populations was retained even if the most linguistically distinct Kashubian speakers were excluded from the analysis (RST=0.00899, P=0.01505; data not shown). Comparison of Y chromosomes associated with etymologically Slavic and German surnames (with frequencies provided in Table 1) did not reveal genetic differentiation within any of the three Polish regional populations for all three (FST, ΦST and RST) genetic distances. Moreover, the German surname-related Y chromosomes were comparably distant from Bavaria and Mecklenburg as the ones associated with the Slavic surnames (Supplementary Figure S2). MDS of pairwise genetic distances showed a clear-cut differentiation between German and Slavic samples (Figure 2). In addition, the MDS analysis revealed the pre-WWII populations from northern, central and southern Poland to be moderately scattered in the plot, on the contrary to modern Polish regional samples, which formed a very tight, homogeneous cluster (Figure 3).
This all seems very reasonable. Modern Poland is probably more homogenous than pre-war Poland in part because modern Poles have cars and trains and can marry people from other parts of Poland much more easily than pre-war Poles could, and possibly because the war itself reduced Polish genetic diversity and displaced much of the population.
Genetic discontinuity along the Polish-German border also makes sense, as national, cultural, and linguistic boundaries all make intermarriage more difficult.
The Discussion portion of this paper is very interesting; I shall quote briefly:
Kayser et al3 revealed significant genetic differentiation between paternal lineages of neighbouring Poland and Germany, which follows a present-day political border and was attributed to massive population movements during and shortly after the WWII. … it remained unknown whether Y-chromosomal diversity in ethnically/linguistically defined Slavic and German populations, which used to be exposed to intensive interethnic contacts and cohabit ethnically mixed territories, was clinal or discontinuous already before the war. In contrast to the regions of Kaszuby and Kociewie, which were politically subordinated to German states for more than three centuries and before the massive human resettlements in the mid-20th century occupied a narrow strip of land between German-speaking territories, the Kurpie region practically never experienced longer periods of German political influence and direct neighbourhood with the German populations. Lusatia was conquered by Germans in the 10th century and since then was a part of German states for most of its history; the modern Lusatians (Sorbs) inhabit a Slavic-speaking island in southeastern Germany. In spite of the fact that these four regions differed significantly in exposure to gene flow with the German population, our results revealed their similar genetic differentiation from Bavaria and Mecklenburg. Moreover, admixture estimates showed hardly detectable German paternal ancestry in Slavs neighbouring German populations for centuries, that is, the Sorbs and Kashubes. However, it should be noted that our regional population samples comprised only individuals of Polish and Sorbian ethnicity and did not involve a pre-WWII German minority of Kaszuby and Kociewie, which owing to forced resettlements in the mid-20th century ceased to exist, and also did not involve Germans constituting since the 19th century a majority ethnic group of Lusatia. Thus, our results concern ethnically/linguistically rather than geographically defined populations and clearly contrast the broad-scale pattern of Y-chromosomal diversity in Europe, which was shown to be strongly driven by geographic proximity rather than by language.1 …
Two main factors are believed to be responsible for the Slavic language extinction in vast territories to the east of the Elbe and Saale rivers: colonisation of the region by the German-speaking settlers, known in historical sources as Ostsiedlung, and assimilation of the local Slavic populations, but contribution of both factors to the formation of a modern eastern German population used to remain highly speculative.8 Previous studies on Y-chromosomal diversity in Germany by Roewer et al17 and Kayser et al3 revealed east–west regional differentiation within the country with eastern German populations clustering between western German and Slavic populations but clearly separated from the latter, which suggested only minor Slavic paternal contribution to the modern eastern Germans. Our ancestry estimates for the Mecklenburg region (Supplementary Table S3) and for the pooled eastern German populations, assessed as being well below 50%, definitely confirm the German colonisation with replacement of autochthonous populations as the main reason for extinction of local Slavic vernaculars. The presented results suggest that early medieval Slavic westward migrations and late medieval and subsequent German eastward migrations, which outnumbered and largely replaced previous populations, as well as very limited male genetic admixture to the neighbouring Slavs (Supplementary Table S4), were likely responsible for the pre-WWII genetic differentiation between Slavic- and German-speaking populations. Woźniak et al18 compared several Slavic populations and did not detect such a sharp genetic boundary in case of Czech and Slovak males with genetically intermediate position between other Slavic and German populations, which was explained by early medieval interactions between Slavic and Germanic tribes on the southern side of the Carpathians. Anyway, paternal lineages from our Slovak population sample were genetically much closer to their Slavic than German counterparts. …
Note that they are discussing paternal ancestry. This does not rule out the possibility of significant Slavic maternal ancestry. Finally:
Our coalescence-based divergence time estimates for the two isolated western Slavic populations almost perfectly match historical and archaeological data on the Slavs’ expansion in Europe in the 5th–6th centuries.4 Several hundred years of demographic expansion before the divergence, as detected by the BATWING, support hypothesis that the early medieval Slavic expansion in Europe was a demographic event rather than solely a linguistic spread of the Slavic language.
I left out a lot of interesting material, so I recommend reading the complete discussion if you want to know more about Polish/German genetics.
Mitochondrial DNA (mtDNA) sequence variation was examined in Poles (from the Pomerania-Kujawy region; n = 436) and Russians (from three different regions of the European part of Russia; n = 201)… The classification of mitochondrial haplotypes revealed the presence of all major European haplogroups, which were characterized by similar patterns of distribution in Poles and Russians. An analysis of the distribution of the control region haplotypes did not reveal any specific combinations of unique mtDNA haplotypes and their subclusters that clearly distinguish both Poles and Russians from the neighbouring European populations. The only exception is a novel subcluster U4a within subhaplogroup U4, defined by a diagnostic mutation at nucleotide position 310 in HVS II. This subcluster was found in common predominantly between Poles and Russians (at a frequency of 2.3% and 2.0%, respectively) and may therefore have a central-eastern European origin. …
The analysis of mtDNA haplotype distribution has shown that both Slavonic populations share them mainly with Germans and Finns. The following numbers of the rare shared haplotypes and subclusters were found between populations analyzed: 10% between Poles and Germans, 7.4% between Poles and Russians, and 4.5% between Russians and Germans. A novel subcluster U4-310, defined by mutation at nucleotide position 310 in HVS II, was found predominantly in common between Poles and Russians (at frequency of 2%). Given the relatively high frequency and diversity of this marker among Poles and its low frequency in the neighbouring German and Finnish populations, we suggest a central European origin of U4-310, following by subsequent dispersal of this mtDNA subgroup in eastern European populations during the Slavonic migrations in early Middle Ages.
In other words, for the most part, Poles, Russians, Germans, and even Finns(!) (who do not speak an Indo-European language and are usually genetic outliers in Europe,) all share their maternal DNA.
Migrants, immigrants, and invaders tend disproportionately to be male (just look at any army) while women tend to stay behind. Invading armies might wipe each other out, but the women of a region are typically spared, seen as booty similar to cattle to be distributed among the invaders rather than killed. Female populations therefore tend to be sticky, in a genetic sense, persisting long after all of the men in an area were killed and replaced. The dominant Y-chromosome haplogroup in the area (R1a) hails from the Indo-European invasion (except in Finland, obviously,) but the mtDNA likely predates that expansion.
These data allow us to suggest that Europeans, despite their linguistic differences, originated in the common genetic substratum which predates the formation of the most modern European populations. It seems that considerable genetic similarity between European populations, which has been revealed by mtDNA variation studies, was further accelerated by a process of gene redistribution between populations due to the multiple migrations occurring in Europe during the past milenia…
It is interesting, though, that recent German invasions of Poland left very little in the way of a genetic contribution. I’d wager that WWII was quite a genetic disaster for everyone involved.
If you want more information, Khazaria has a nice list of studies plus short summaries on Polish DNA.
Commentator Unknown123 asks what we can tell about the differences between German and Polish DNA. Obviously German is here referring to one of the Germanic peoples who occupy the modern nation of Germany and speak a Germanic language. But as noted before, just because people speak a common language doesn’t necessarily mean they have a common genetic origin. Germans and English both speak Germanic languages , but Germans could easily share more DNA with their Slavic-language speaking neighbors in Poland than with the English.
It is suggested by geneticists that the movements of Germanic peoples has had a strong influence upon the modern distribution of the male lineage represented by the Y-DNAhaplogroup I1, which is believed to have originated with one man, who lived approximately 4,000 to 6,000 years somewhere in Northern Europe, possibly modern Denmark … There is evidence of this man’s descendants settling in all of the areas that Germanic tribes are recorded as having subsequently invaded or migrated to.[v] However, it is quite possible that Haplogroup I1 is pre-Germanic, that is I1 may have originated with individuals who adopted the proto-Germanic culture, at an early stage of its development or were co-founders of that culture. Should that earliest Proto-Germanic speaking ancestor be found, his Y-DNA would most likely be an admixture of the aforementioned I1, but would also contain R1a1a, R1b-P312 and R1b-U106, a genetic combination of the haplogroups found among current Germanic speaking peoples. …
According to a study published in 2010, I-M253 originated between 3,170 and 5,000 years ago, in Chalcolithic Europe. A new study in 2015 estimated the origin as between 3,470 and 5,070 years ago or between 3,180 and 3,760 years ago, using two different techniques. It is suggested that it initially dispersed from the area that is now Denmark.
A 2014 study in Hungary uncovered remains of nine individuals from the Linear Pottery culture, one of whom was found to have carried the M253 SNP which defines Haplogroup I1. This culture is thought to have been present between 6,500 and 7,500 years ago.
In 2002 a paper was published by Michael E. Weale and colleagues showing genetic evidence for population differences between the English and Welsh populations, including a markedly higher level of Y-DNA haplogroup I in England than in Wales. They saw this as convincing evidence of Anglo-Saxon mass invasion of eastern Great Britain from northern Germany and Denmark during the Migration Period. The authors assumed that populations with large proportions of haplogroup I originated from northern Germany or southern Scandinavia, particularly Denmark, and that their ancestors had migrated across the North Sea with Anglo-Saxon migrations and DanishVikings. The main claim by the researchers was:
“That an Anglo-Saxon immigration event affecting 50–100% of the Central English male gene pool at that time is required. We note, however, that our data do not allow us to distinguish an event that simply added to the indigenous Central English male gene pool from one where indigenous males were displaced elsewhere or one where indigenous males were reduced in number … This study shows that the Welsh border was more of a genetic barrier to Anglo-Saxon Y chromosome gene flow than the North Sea … These results indicate that a political boundary can be more important than a geophysical one in population genetic structuring.”
In 2003 a paper was published by Christian Capelli and colleagues which supported, but modified, the conclusions of Weale and colleagues. This paper, which sampled Great Britain and Ireland on a grid, found a smaller difference between Welsh and English samples, with a gradual decrease in Haplogroup I frequency moving westwards in southern Great Britain. The results suggested to the authors that Norwegian Vikings invaders had heavily influenced the northern area of the British Isles, but that both English and mainland Scottish samples all have German/Danish influence.
But the original question was about Germany and Poland, not England and Wales, so we are wandering a bit off-track.
A score of “1” on this graph means that the two populations in question are identical–fully inter-mixing. The closer to 1 two groups score, the more similar they are. The further from one they score, (the bigger the number,) the more different they are.
For example, the most closely related peoples on the graph are Austrians and their neighbors in southern Germany and Hungary (despite Hungarians speaking a non-Indo-European language brought in by recent steppe invaders.) Both groups scored 1.04 relative to Austrians, and a 1.08 relative to each other.
Northern and southern Germans also received a 1.08–so southern Germans are about as closely related to northern Germans as they are to Hungarians, and are more closely related to Austrians than to northern Germans.
This might reflect the pre-Roman empire population in which (as we discussed in the previous post) the Celtic cultures of Hallstatt and La Tene dominated a stretch of central Europe between Austria and Switzerland, with significant expansion both east and west, whilst the proto-Germanic peoples occupied northern Germany and later spread southward.
The least closely related peoples on the graph are (unsurprisingly) the Sami (Lapp) town of Kuusamo in northeastern Finland and Spain, at 4.21. (Finns are always kind of outliers in Europe, and Spaniards are kind of outliers in their own, different way, being the part of mainland Europe furthest from the Indo-European expansion starting point and so having received fewer invaders.
So what does the table say about Germans and their neighbors?
South Germany 1.08
Czech Repub 1.15
North Germany 1.08
Czech Repub 1.16
Czech Repub 1.09
North Germany 1.18
South Germany 1.23
Obviously I didn’t include all of the data in the original table; all of the other sampled European groups, such as Italians, Spaniards, and Finns are genetically further away from north and south Germany and Poland than the listed groups.
So northern Germany and Poland are quite closely related–even closer than northern Germans are to the French (whose country is named after a Germanic tribe, the Franks, who conquered it during the Barbarian Migrations at the Fall of the Roman Empire,) or the Swiss, many of whom speak German. By contrast, southern Germany is more closely related to France and Switzerland than to Poland, but still more closely related to the Poles than Italians or Spaniards.
Welcome back, everyone. Yesterday we were discussing Ainu genetics. Today we’re still discussing Ainu genetics, but this time we’re discussing mtDNA instead of Y DNA.
Based on analysis of one sample of 51 modern Ainus, their mtDNA lineages have been reported to consist mainly of haplogroup Y …haplogroup D … haplogroup M7a … and haplogroup G1 … Other mtDNA haplogroups detected in this sample include A (2/51), M7b2 (2/51), N9b (1/51), B4f (1/51), F1b (1/51), and M9a (1/51). Most of the remaining individuals in this sample have been classified definitively only as belonging to macro-haplogroup M. According to Sato et al. (2009), who have studied the mtDNA of the same sample of modern Ainus (n=51), the major haplogroups of the Ainu are N9 (14/51 = 27.5%, including 10/51 Y and 4/51 N9(xY)), D (12/51 = 23.5%, including 8/51 D(xD5) and 4/51 D5), M7 (10/51 = 19.6%), and G (10/51 = 19.6%, including 8/51 G1 and 2/51 G2); the minor haplogroups are A (2/51), B (1/51), F (1/51), and M(xM7, M8, CZ, D, G) (1/51).
Note that Y (confusingly named) is a sub-haplogroup of N9. It’s commonly found in groups around the Sea of Okhotsk, (including the Ainu,) and in Indonesia, similar to the distribution of Sundadont teeth. Haplogroup D is found in Native Americans (highest frequency among the Aleuts,); Siberians, Ainu, east Asians, Japanese, etc. M7 is kind of generically east-Asian, with high frequency in Japan. In other words, Ainu maternal DNA is fairly similar to that of Japan at large + nearby Siberians.
So how closely related are the Ainu to rest of the Japanese?
Given the archaeology of the area and what we now know of the genetics, it looks like the Ainu were descended primarily from two main groups:
Over the past hundred years or so, though, the Ainu have purposefully intermarried with the non-Ainu Japanese, who are themselves descended from a mix of:
Yayoi, who invaded around 300 BC, conquering the Jomon.
We’d expect therefore for the Ainu and Japanese to share a fair amount of their mtDNA (the Yayoi probably absorbed Jomon women into their groups;) but not much Y DNA. According to Wikipedia:
Studies published in 2004 and 2007 show the combined frequency of M7a and N9b were observed in Jomons and which are believed by some to be Jomon maternal contribution at 28% in Okinawans (7/50 M7a1, 6/50 M7a(xM7a1), 1/50 N9b), 17.6% in Ainus (8/51 M7a(xM7a1), 1/51 N9b), and from 10% (97/1312 M7a(xM7a1), 1/1312 M7a1, 28/1312 N9b) to 17% (15/100 M7a1, 2/100 M7a(xM7a1)) in mainstream Japanese.
A recent reevaluation of cranial traits suggests that the Ainu resemble the Okhotsk more than they do the Jōmon. This agrees with the reference to the Ainu being a merger of Okhotsk and Satsumon referenced above.
Now certainly, if we can use DNA testing to tell that someone is “half Spaniard, a quarter Finnish, and a quarter Czech, with 3% Neanderthal DNA,” then we can use DNA testing to tell what %s of someone’s ancestry are Japanese, Ainu, Jomon, Yayoi, Siberian, etc.–it’s just a matter of getting enough relevant samples. The only major issue I could see getting in the way is if there actually is no such thing as a genetically “pure” Ainu, but rather a bunch of small Ainu groups with varying levels of admixture from all of the other groups. For example, there is no such thing as “Turkic” genetics–all “Turkic” groups speak Turkic languages, take great pride in being Turkic, and presumably have cultural connections, but genetically they are quite diverse. The situation is similar with Jewish groups. 2000 years ago, most Jews were genetically “Jewish,” but today, the vast majority of Jews are at least 50% non-ancient Hebrew by DNA.
But of course, genetics doesn’t tell you much about the lives of modern Ainu.
Many people theorize recent connections between all of the peoples along the north Pacific rim, from Japan to Oregon, and northward across Canada, based on similar abstract, geometric art styles; lifestyles; and documented contacts. The eternally-controversial Kennewick man (a 9,000 year old skeleton discovered in Washington State,) was initially described by some anthropologists as resembling an Ainu man. Mister Kennewick has since been proven to be related to modern Native Americans–Native Americans may simply have looked different 9,000 years ago.
I look forward to more research on connections between circum-polar and circum-Pacific peoples.
Most of the information easily available on the internet speaks of the Ainu in the past tense: The Ainu were hunter-gatherers; the Ainu worshiped; the Ainu were conquered. The photographic situation is similar: an image search for “Ainu” brings up a few dozen century-old photos and not much else.
But the modern Ainu, of course, do not live in the past–they live in today, primarily in the very modern city of Sapporo. The modern Ainu are not hunter-gatherers (although the entire nation of Japan remains highly dependent on fishing for its nutrition;) they are doctors and shop-keepers, office workers and artists. They go to school, keep up with modern fashions, play video games, and ride the shinkansen just like everyone else in Japan.
Wikipedia (and everyone else) estimates that about 25,000 Ainu live today in Japan, with the caveat that since the Ainu don’t always bother to mention their ancestry, there could be a couple hundred thousand who just haven’t been counted.
Due to years of inter-marrying, the vast majority of today’s Ainu are at least part Japanese. One reference I recall estimated that about 300 pure-blooded Ainu remained in 1950; another estimated that 200 remain today.
There are also some Ainu living in Russia; according to Wikipedia, about 100 Russians tried to identify as Ainu in the 2010 census, and nearly a thousand people with some degree of Ainu ancestry live in the area.
Alas for my purposes as a writer, these few remaining folks appear to be living their lives out in anthropological anonymity, rather than posting selfies tagged #RealAinu all over the internet.
The one thing everyone likes to argue about in threads about the Ainu is whether or not they look like white people.
It’s kind of dumb to fight about, since obviously Ainu look like Ainu.
Okay, okay. Don’t start a flame war. According to Wikipedia:
Turner found remains of Jōmon people of Japan to belong to Sundadont pattern similar with the Southern Mongoloid living populations of Taiwanese aborigines, Filipinos, Indonesians, Thais, Borneans, Laotians, and Malaysians. …
Your Y-haplogroup traces your paternal ancestry, because men (and only men) inherit their Y-chromosomes from their fathers. Your M or Mt-DNA, (short for mitochondrial DNA,) hails exclusively from your mother (and both men and women have Mt-DNA, because we all have mitochondria.)
Often when one group of people conquers another group of people, their descendants end up with Y-DNA from the conquerors and MtDNA from the conquered, but there are other ways people come together, like folks intermarrying with their neighbors.
(Presumably this study was done with relatively pure-blooded Ainu.)
The distribution of Haplogroup D-M174 is quite suggestive: Ainu, Tibetans, and Andaman Islanders. These are three (historically) highly isolated groups–one of the world’s few remaining basically uncontacted peoples, the Sentinelese, (they’ll put a spear in you if you land on their island) live in the Andaman Islands. The Tibetans, as I’ve mentioned, have inherited DNA from the Denisovans–cousins of the Neanderthals who interbred with their ancestors–that lets them breathe more easily at high altitudes than anyone else on Earth, making it rather hard for non-Tibetans move there, much less conquer and occupy it [Note: I wouldn’t be surprised if the Nepalese or other folks who also live up in the Himalayas also have the adaptation; this isn’t meant to be a discussion of modern political borders.] And the Ainu basically live on the far edge of Asian at the southern edge of Siberia–northern Japan is the snowiest populated place in the world.
“Sinodont” and “sundadont” actually refer to two different tooth shapes.
Tibetans and Andaman Islanders are definitely Asians–they clade with other Asians in the Greater Asian Clade–but they don’t look much alike. You wouldn’t mistake them for Caucasians, though.
Haplogroup D-M174 is believed to have evolved about 50-60-thousand years ago, presumably in Asia. This was shortly after the Out-of-Africa event, which occurred about 70,000 (or possibly 100,000 years ago [there might have been more than one OOA.]) D-M174 is so old that its “parent” haplogroup is DE, which is found in Africa and Asia.
By contrast, the mutation to the EDAR-gene which gives Han Chinese (the Asian ethnic group Americans are most familiar with) and Japanese their characteristic hair, skin, tooth shape, build, etc., (EDAR is pretty incredible in that way) only occurred 30,000 years ago–that is, the Ainu split off from other Asians 20-30 thousand years before what we think of as “the Asian look” had even evolved.
For that matter, Caucasian themselves only appear to have split off from Asians around 40,000 years ago–10,000 years before EDAR mutated, but 10-20,000 years after D-M174 arose.
Or to put it another way:
About 70,000 years ago, an intrepid band of explorers left Africa. Presumably, these people looked African, but I don’t know exactly which Africans these ancient people looked like–perhaps they didn’t really look like any modern group; perhaps they looked a lot like most Sub-Saharan Africans; perhaps they looked like the Bushmen, noted for their tawny skin tones and more “Asian” look than other Sub-Saharans. I don’t know yet.
About 60,000 years ago, the band split, and one group spread far across Asia. Their modern descendants are the Ainu, Tibetans, and Andaman Islanders.
The other group presumably hung out in central Eurasia, until about 40,000 years ago, when it definitively split. One group went west and became the Caucasians; the other became the Han.
Around 30,000 years, the distinctive EDAR mutation that gives east-Asians their “typical” appearance evolved.
Around 10,000 years ago, more or less, Europeans began getting lighter, and “whiteness” as we know it evolved.
So… could the Ainu retain some traits or have never obtained some traits–like epicanthic folds at the corners of their eyes–which make them look more like their ancestral group, to which the ancestors of both Asians and Caucasians belonged? Sure. Could they have just evolved traits to deal with the extremely cold, near-Siberian environment they lived in that happened to resemble traits that evolved in European populations dealing with a similarly cold environment? Sure.
But are they Caucasians? Not even remotely.
And in my opinion, they don’t look Caucasian, at least not when their faces aren’t covered with big, bushy beards. (The modern Ainu tend to shave.) Take, for example, Oki Kano, an Ainu musician. Nothing about his appearance says, “Mysterious tribe of lost Caucasians.”
Back to Wikipedia:
In a study by Tajima et al. (2004), two out of a sample of sixteen (or 12.5%) Ainu men have been found to belong to Haplogroup C-M217, which is the most common Y-chromosome haplogroup among the indigenous populations of Siberia and Mongolia. … Some researchers have speculated that this minority of Haplogroup C-M217 carriers among the Ainu may reflect a certain degree of unidirectional genetic influence from the Nivkhs, a traditionally nomadic people of northern Sakhalin and the adjacent mainland, with whom the Ainu have long-standing cultural interactions.
The Nivkhs live basically next door and have a lot of cultural similarities–for example, both groups traditionally had shamanic rituals involving bears, which they raised and then sacrificed:
Nivkh Shamans also presided over the Bear Festival, a traditional holiday celebrated between January and February depending on the clan. Bears were captured and raised in a corral for several years by local women, treating the bear like a child. The bear was considered a sacred earthly manifestation of Nivkh ancestors and the gods in bear form (see Bear worship). During the Festival, the bear would be dressed in a specially made ceremonial costume. It would be offered a banquet to take back to the realm of gods to show benevolence upon the clans. After the banquet, the bear would be sacrificed and eaten in an elaborate religious ceremony. Often dogs were sacrificed as well. The bear’s spirit returned to the gods of the mountain ‘happy’ and would then reward the Nivkh with bountiful forests. …
While haplogroup D-M174 shows affinity with more southerly Asian groups, like the Tibetans or Andaman Islanders, haplogroup C-M217 is found throughout northern Asia (principally Siberia) and northern North America.
Let’s consider the similarities between the fairy fountains found in Nintendo’s new Legend of Zelda installment, Breath of the Wild, and the enormous blooms of our terrestrial Rafflesia genus.
Rafflesia Arnoldii hold the record for world’s largest flowers, growing regularly to a width of 3 feet and weighing up to 24 pounds. Their central chamber is large enough to put a baby in, if you aren’t too perturbed by their odd spiky structures and horrific smell.
The Fairy Fountain is obviously the largest flower in Breath of the Wild and has a central chamber similar to Rafflesia’s; an enormous fairy woman lives inside.
Rafflesia is a parasitic plant which actually has no stems, leaves, roots, or even chlorophyll! (This has made tracing its genetic relationships to other plants difficult for scientists, because most of what we know about plant relationships is based off comparing differences in their chlorophyll’s DNA.) The only visible parts of the plant are its buds and, subsequently, the flowers they open into.
Likewise, the Fairy Fountain has no leaves, stems, or other visible plant parts–it is just a bud that opens into a flower. (However, the fairy fountain bud is green. Perhaps it would have looked too much like a giant nut if it were brown like the true Rafflesia.)
The rest of Rafflesia’s structure is hidden within the vines it parasitizes. When not in bloom, it’s just a network within the vine, just as a mushroom’s principle structures lie hidden within the ground or rotting logs.
The Fairy Fountain is surrounded by mushrooms, which suggest their similarity to the fountain’s hidden structure.
Rafflesia’s enormous size is due to the fact that it is pollinated by carrion flies, who are attracted to the largest carcasses they can find. Unfortunately, this also means that Rafflesia smells like rotting meat, earning it various unsavory names like “corpse flower.” It also possesses the remarkable ability to generate heat, creating a warm, comfortable environment for flies to congregate in.
In Breath of the Wild, the Fairy Fountain is also home to flies, though these are thankfully the much less smelly, tiny winged fairy kind.
“The pollen is incredible,” Davis continues. In most plants, the pollen is powdery, but in Rafflesia, it is “produced as a massive quantity of viscous fluid, sort of like snot, that dries on the backs of these flies—and presumably remains viable for quite a long time,” perhaps weeks. In their pollinating efforts, the flies may travel as much as 12 to 14 miles.
I don’t have a very good sense of scale in Breath of the Wild, but 12 or 14 miles between Fairy Fountains sounds about right. By picking up fairies at one fountain and carrying them to the next, Link is helping this likely endangered Hylian species reproduce.
Likewise, the center of the enormous Fairy Fountains is filled not with powder, but some kind of… liquid.
Or it might just be water:
Vines move massive quantities of water, which may be one of the physiological reasons that Rafflesia colonize them, he explains. The flowers, which to the touch are like “a Nerf football that is wet,” are mostly water themselves, and the exponential growth of the blooms in the final stages of development is made possible “primarily by pumping massive quantities of water into the flower.”
That’s a lot like what I imagine the Fairy Fountain would feel like, too.
But the really interesting thing about Rafflesia is their genes:
Given his mandate to establish a phylogeny for the order Malpighiales, Davis set out, dutifully, to duplicate the published result for Rafflesia. What he found was not just unexpected. It absolutely astounded him. Some of the genes he sequenced confirmed that Rafflesia were indeed part of Malpighiales—but other sequenced genes placed them in an entirely different order (Vitales)—with their host plants. Davis had stumbled upon a case of massive horizontal gene transfer, the exchange of genetic information between two organisms without sex. …
The work is also facilitating the identification of Rafflesia’s past hosts, since many of the transgenes Davis found came from lineages of plants other than Tetrastigma, the current host. These ancient parasite/host associations, a kind of molecular fossil record, could be used to elucidate the timing and origin of plant parasitism itself.
Davis found that the host plant contributed about 2 percent to 3 percent of Rafflesia’s expressed nuclear genome (genes in the cell nucleus), and as much as 50 percent of its mitochondrial genome (genes that govern energy production). The sheer scale of the transfer was so far-fetched, his collaborator at the time at first didn’t believe that the findings could be accurate. The paper, published in 2012, demonstrated that intimate host/parasite connections are potentially an important means by which horizontal gene transfers can occur. And it showed that the physiological invisibility of Rafflesia within the host is echoed in its genes: the host and parasite share so much biology that the boundaries between them have become blurred.
Intriguingly, some of the transferred genes swap in at precisely the same genetic location as in the parasite’s own genome. “One of the ideas that we are exploring,” says Davis, “is whether maintaining these transferred genes might provide a fitness advantage for the parasite. Might these transfers be providing a kind of genetic camouflage so that the host can’t mount an immune response to the parasite that lives within it?”
And finally, Rafflesia flowers and the Fairy Fountain are basically the same color: both are both reddish with white mottling.
In the genomic age, it is now easy to compare the DNA of people from around the world. And it has indeed revealed that our racial categories are fuzzy proxies for genetic difference—an African man may be more closely related to an Asian than to another African.
From there, Zhang basically tries to argue that race doesn’t real even though genetics and medical science sure make it look real, that the differences in the distribution of genetic traits in large, historically isolated populations don’t matter because of a few tiny populations that are the genetic equivalent of the Basque language.
Remember, the world’s entire population of Bushmen wouldn’t even fill the Texas A&M football stadium. Combine them with a few other tiny populations, like the Khoikhoi and Pygmies, and you’re still looking at <1 million people. Meanwhile, there are billions of Europeans, west Africans, and east Asians.
Mundane racial categories work just fine for the vast majority of people, including the vast majority of Americans, who are not drawn from a rainbow of racially-mixed groups like Tuaregs or fringe outliers like the Bushmen, but from distinct populations of West Africans, Europeans (primarily NW Euros,) Native Americans, and East Asians. If I say someone is “black” or “white,” not only do you understand what I mean, there is an actually consistent genetic reality underlying my statements–in almost 100% of cases, a genetic test would in fact confirm that the people I call “black” are actually primarily Sub-Saharan African by ancestry and the people I call “white” are primarily European by ancestry. Exceptions like Rachel Dolezal are quite rare.
Zhang is trying to argue that you can’t make a reasonable argument about the average distribution of traits between whites, blacks, and Asians in the US because there is a handful of tiny, genetically isolated populations over in Africa. A does not follow from B.
On the other side of the coin, we have people who believe it’s morally imperative to only marry people from one’s own race.
Most of the time, people fall in love with people from their own culture and ethnic group. This is what we’d expect, because you’re more likely to meet and share values with people from your own group. (Interestingly, most people are more genetically similar to their spouses than they are to the average person in their community, not because they married a close relative, but because similar genes make for similar people.)
But some people, for whatever reasons, marrying within their own group isn’t a real option. (White men who are under 5’5″, for example.) These people are looking out for their own best interests–really, if you’re considering calling Derbyshire a race traitor, you’re probably thinking too much about other people’s business.
Capitalism works because it self-corrects; it allows consumers to pick the best products at the best prices, and companies to hire the most talented workers for the best wages. Unlike socialism, where companies are told what and how much to produce, consumers are told what to buy and how much it will cost, and ultimately people starve in the streets, capitalism actually works. Self-interest is a powerful organizing principle that has radically increased the welfare of billions of people over the past century.
And capitalism doesn’t care about race.
Where people live in close proximity to people of other races, some of them will fall in love.
That said, don’t date people for status points or because you’re trying to prove how not-racist you are. Like Obama’s parents, most inter-racial couples don’t stay together; the majority of mixed-race children have parents who are not married–according to one study, 92% of biracial children with black fathers are born out of wedlock and 82% end up on government assistance because their fathers do not bother to take care of them.
And if you are ever tempted to compare your vagina to the UN because of the sheer number of different ethnicities that have been in it, you need to stop and re-evaluate your life for multiple reasons.
Ultimately, real-life decisions should be based on real-life concerns.