Whither HBD: Happy 1,000 posts

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Gratuitous pic of Niels Bohr and Einstein, 1925, because this is my party.

This blog is now 1,000 posts long, which I think calls for a bit of celebration.

I started this blog because I found the idea that evolution–a process normally thought of as turning fins to feet and gills to lungs–could also code for emergent, group-level behavior like the building of termite mounds or nation states fascinating. Could evolution code for other things? Could it give us male and female behavior? Emotions? Political preferences?

I started reading JayMan’s work, then Peter Frost and HBD Chick, and of course Cochran and Harpending. Each of these blogs had new (at least to me) and fascinating ideas about why humans behave the many ways they do. Then came Slate Star Codex and Unqualified Reservations. There were others, of course; a complete listing of one’s intellectual predecessors is always impossible.

Evolution is ultimately a numbers game: if more people who do X have children than people who do Y, then X is likely to become more common than Y–even if we all believe that Y is better than X.

This gets interesting when X is not obviously mediated by genetics–your eye color, sans contacts, is clearly genetic, but the number of years you spend in school is influenced by external factors like whether schools exist in your society. This is where some people get hung up on causation. We don’t need to posit a gene that causes people to get more or less school. Maybe your village has a school because a mountain climber got lost nearby, your village rescued him, and in gratitude, he built you a school, while the village on the other side of the mountain doesn’t have a school because no mountain climber got lost there. Once a school exists, though, it can start having effects, and if those effects are not random, we’ll see genetic correlations.

If people who have more education make more money and end up buying more food and raising more children, then school is exerting a selective effect on society by causing the kids who happened to live near the school to have more children. From an ecological standpoint, the school is operating like a spring in a desert–we get more growth near the spring than far away from it, and whatever traits were common in the village–even ones that have nothing to do with education–will become more numerous in the overall population. If this trend continues, then the cultural habit of “going to school” will continue to proliferate.

We can also posit the opposite case: in the village with the school, kids spend many years at school and end up marrying later and are more educated about things like “birth control” than their neighbors on the other side of the mountain. The kids on the other side of the mountain marry younger and have a bunch of unintended children. In this case, education is suppressing fertility; in this niche, education is like a drought. The educated kids have fewer children of their own, and whatever traits the uneducated kids happen to have spread through society because there are now much more of them (at least as a percent of the total). If this trend continues, then the cultural habit of “going to school” may well die out.

In both of these cases, education caused a change in the distribution of genetic traits in the overall population without requiring any genetic predispositions from the students involved. We are looking at the evolution of the whole society.

But this is a highly constrained example; it is rare in places like the modern US to find areas where one village has a school and the next does not. Once schools are everywhere, they’re not going to select for (or against) “living near a school.” The traits that cause a person to attend more years of schooling or do better in school will be less random–traits like conscientiousness, ability to recognize letters, or family income. In an agricultural society with no schools, raw, physical strength may be at a premium as people must wrest their living from the soil, rocks, trees, and beasts. This selects for physical strength. Once we introduce schools, if the better educated have more children, then physical strength becomes less important, and its prominence in the next generation diminishes. The ability to sit in a chair for long hours may be positively selected, leading to a proliferation of this trait.

This is gene-culture co-evolution–a cultural change can shift the balance of genes in a society, and that in turn can cause further cultural changes, which cause more genetic changes.

I would like to pause and note just how annoying the “but you haven’t proven causation!” crowd is:

Imagine if I said that I thought the blood circulates through the body in a loop instead of being generated anew by the heart with every pump, and someone protested that blood couldn’t possibly circulate because I hadn’t shown any way for blood to get from the arteries to the veins and back to the heart.

This was a real debate in physiology. That the heart pumps is obvious. That veins and arteries carry blood is also obvious. That people die if you cut them open and let the blood drain out, though, mystified doctors for centuries.

Capillaries, unfortunately for many patients, are too small to see with the naked eye. Without any mechanism to return blood from the arteries to the heart, doctors refused to believe that it did. They instead believed that blood was produced anew with every heartbeat and was consumed at our extremities. Bleeding patients, therefore, shouldn’t cause any great difficulties.

The fact that we could not see capillaries before the invention of the microscope should not have caused doctors to reject the theory of circulation, only to say that a mechanism had not yet been found to make it work. The circulation hypothesis did a better job of explaining various facts of human anatomy–like the existence of veins carrying blood to the heart and the habit of patients to die after bleeding–than the heart-generation hypothesis.

The insistence on clinging to the older theory due to the lack of a capillary mechanism lead, of course, to the deaths of thousands of patients. (For more on the history of medicine, anatomy, and circulation, I recommend William Bynum’s A Little History of Science.)

How something works is vastly secondary to the question of whether it works at all in the first place. If it works, it works. If you can’t figure out how, you call it magic admit that you don’t know and hope that someday it’ll be clear. What you don’t do is claim that a thing cannot be true or cannot actually work simply because you don’t understand how it happens.

I don’t understand how airplanes stay in the sky, but that doesn’t make them fall down. Reality doesn’t stop just because we don’t understand it; to think that it does is pure, asinine hubris.

The next objection I commonly hear to the idea that cultural changes (like the proliferation of schools) could trigger changes in the genetic makeup of society is that “evolution doesn’t work that fast.”

This is a funny objection. The speed of evolution depends on the nature of the trait we are discussing. Developing a radically new trait, or greatly modifying an existing one, such as developing the ability to breath air instead of water, does indeed take a long time–sometimes millions or even billions of years. But simply modifying the distribution of existing traits in a population can be done nearly instantly–if an invading army lops the heads off of anyone over 5’9″, the average height of the population will fall immediately. From a genetic perspective, this is “negative selection” against height, and the population has “evolved” to be shorter.

(You might object that this is too artificial an example, so consider the inverse: a situation where everyone over a certain size used to die, but due to environmental changes they now survive. Modern obstetrics and the cesarean section have rescued mothers of large babies from the once-common fate of death in childbirth. This was of course often fatal to the infants, as well, and prevented their parents from producing any further children. Large babies were a serious evolutionary problem for our ancestors, but much less so for us, which has probably contributed to the rise in average heights over the past century.)

Usually selection is less extreme, but the point remains: traits that already exist (and vary) in a population, like height, weight, blood type, or temperament, can be selected for (or against) on very short timescales.

In fact, human societies are always selecting for some traits; this means that we are always evolving. The distribution of traits in humans today is not the same as the distribution of traits in humans 20 years ago, much less 100 years ago.

And we can look at all of the things humans are being selected for (or selecting themselves for) and speculate how this will change society. Religious people have more children than atheists, and some religions produce far more children than other religions. This trend is juxtaposed against the massive rise in atheism over the past few decades. Will atheism continue to spread to the children of the religious, or will the religious “core” be effectively immune and overwhelm the remaining agnostics with numbers?

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Source: Do Schooling and City Living lead to Fewer Babies?

Education (or perhaps it is just a proxy for intelligence) seems to have different effects on different folks and different levels of society. Highschool dropouts have a lot of kids. People with PhDs have a fair number of kids. People who have merely graduated from college, by contrast, have the fewest kids.

Fertility is also different for men and women, with more educated women taking a bigger fertility hit than educated men.

Any discussion of “what’s up with the American middle/working class” has to address facts like these–our country is effectively bifurcating into two “success” models: one very high achieving and one very low achieving. The middle, it seems, is getting cut out.

But we can apply evolutionary theory to much more than humans and their societies. We can analyze ideas, transportation networks, technology, etc.

My first–and probably best–idea in this area was that the idea that the way we transmit ideas influences the nature of our ideas. One of the biggest changes of the past century has been a massive change in the way we communicate, from the rise of mass media to the explosion of social media. Before radio and TV, most people got most of their information from people they knew personally, mostly their families. Today, we get most of our information from total strangers.

Ideas we get from strangers I refer to as meme viruses, (meme as in “unit of idea,” not “funny picture on the internet”) because horizontal transmission resembles the transmission of viruses. Ideas we get from our families I refer to as mitochondrial memes, because vertical transmission resembles the transmission of mitochondrial DNA.

Since the interests of strangers are different from the interests of your close family (your parents are much more interested in you making lots of money, getting married, and making grandbabies than strangers are), they will tend to promote different sorts of ideas. Your parents generally want you to succeed, while strangers would prefer that you do things that help them succeed.

It is this change in the way we communicate, rather than the actions or intentions of any particular group, that I think explains the rise of many modern political trends. (This is the condensed version; I recommend reading one of my posts on memes if you want more.)

I am obviously interested in politics, but not in the conventional sense. I have very little interest in anything associated with particular people in politics, outside of a few historical figures. I have no interest in the latest thing Nancy Pelosi or Emmanuel Macron has been up to. I think people place too much importance on individuals; I am more interested in broad trends (like the spread of technology) that are much bigger and further-reaching than any individual politicians (often their bigger than individual countries).

I’ve come over the years to the conclusion that conventional politics drive people to do (and say) very stupid things. People develop a tribal identity attached to one side or another, and suddenly everything their side does is good and sensible, and everything the other side does is nefarious and dumb. This is not a bad instinct when your enemies have pointy spears and want to turn you into lunch, but it’s terrible when your enemy disagrees with you on optimal interest rates.

My second purpose in founding this blog was to reach out to people who were, as I see it, harmed by the cult-like behavior of modern leftism. When I say “cult-like,” I mean it. Atheism is on the rise, but religious thinking and behavior remains strong. When peoples’ self-identities as “good people” become linked to their membership in political tribes, the threat of excommunication becomes particularly powerful.

Here’s a public example:

… far more unsettling was what happened two weeks later, when knitters who claim to be champions of social justice went after a gay man within the community because he’d written a satirical poem suggesting (correctly) that all the recent anti-racism mobbings might be having a toxic effect on the community. …

The next day, Taylor’s husband Benjamin Till, a composer (who also happens to be Jewish) posted on Sockmatician’s account: “This is Nathan’s husband, Benjamin. At 3 pm today, Nathan was admitted to [the emergency room at] Barnet Hospital. …

Till also wrote on his blog about what had happened:

… Nathan disabled comments when the sheer weight of them became too much, but the following morning, his other Instagram posts, and then his Twitter feed had been hijacked by the haters. The taunts continued. He was a white supremacist, a Nazi apologist…He started obsessively reading the posts but became increasingly worked up, then more and more erratic and then suddenly he snapped, screaming like a terrified animal, smashing boxes and thumping himself. I was forced to wrestle him to the ground and hold onto him for dear life as the waves of pain surged through his body. He made a run for the car keys. He said he wanted to drive at 100 miles per hour until he crashed. I called our doctor and they could hear him screaming in the background and said I was to immediately take him to [the hospital], where he was instantly assessed and put on suicide watch …

This was not the end of Nathan’s ordeal at the hands of people who supposedly believe in “social justice” and helping the powerless, as people continued piling on (yelling at him in public) because of the “harm” he had caused.

I wish I could reach out to everyone like Nathan and tell them that they’re not bad, cults are bad.

The right has its own issues, but I come from a leftist background and so am responding to what I know personally, not abstractly. 

From time to time I get a question about the future of HBD (human bio-diversity). The online HBD community was quite vibrant about a decade ago, but many of the brightest lights have faded. Henry Harpending of Westhunter and co-author of The 10,000 Year Explosion has sadly passed away. HBD Chick and Jayman are both occupied with their own lives.

The future of HBD isn’t in blogs or the internet generally (though we can read about it here). It’s over in real genetics research. Yes, there are some subjects that academics don’t want to touch for fear of losing their jobs, but there are many researchers forging paths into fascinating new territory. The field of ancient DNA is unlocking the story of human migration and dispersal, from Neanderthals to Anglo Saxons. Thanks to aDNA, we’ve discovered a whole new Human species, the Denisovans, that interbred with the ancestors of modern Homo sapiens (as did the Neanderthals). We have also discovered “ghost” species in our DNA that we have no name for.

The field of modern DNA is also advancing; we’re learning new things all the time. CRISPRing humans is just one fascinating possibility.

Imagine the ability to remove simple genetic flaws that cause painful and fatal diseases, make ourselves beautiful or smarter. How much are 20 IQ points worth? One study found that people with IQs of 100 average $58,000 a year, while 120s made $128,000. $70,000 a year, averaged over a few decades of working life, (less intelligent people tend to enter the workforce and start earning younger, so it’s not a simple multiplication problem), adds up quickly.

Let’s imagine a scenario in which CRISPR actually works. Only the wealthy–and perhaps those with genetic diseases willing to shell out thousands or covered by insurance–will be able to afford it. The current bifurcation trend will become even more extreme as the poor continue reproducing normally, while the wealthy make themselves smarter, healthier, and prettier.

But if CRISPR confers advantages to society as a whole–for example, if smarter people make fabulous new inventions that everyone benefits from–then we could see foundations, charities, and even welfare programs aimed at making sure everyone has the CRISPR advantage.

After all, if an extra year in school boosts IQ by 3.4 points (I’m not saying it does, but let’s assume), then 6 extra years in school will give you 20.4 points. We pay about $10,600 per pupil per year for public schools, so those six years are worth $63,600. If you can CRISPR 20 IQ points for less, then it’s a better deal.

Of course, CRISPR might just be a pipe dream that gives people cancer.

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Isaac Newton

Whatever happens, the real future of HBD lies in real labs with real budgets, not online blogs. I’m just here to share, discuss, and think–and hopefully there will be enough interesting ideas to discuss for another thousand posts.

Thanks for being part of all these discussions. Blogs are nothing without readers, after all.

What does “Heritable” mean? 

“Heritable” (or “heritability”) has a specific and unfortunately non-obvious definition in genetics.

The word sounds like a synonym for “inheritable,” rather like your grandmother’s collection of musical clocks. Musical clocks are inheritable; fruit, since it rots, is not very inheritable.

This is not what “heritable” means.

“Heritability,” in genetics, is a measure of the percent of phenotypic variation within a population that can be attributed to genetics.

Let me clarify that in normal speak. “Phenotype” is something you can actually see about an organism, like how tall it is or the nest it builds. “Phenotypic variation” means things like “variation in height” or “variation in nest size.”

Let’s suppose we have two varieties of corn: a giant strain and a dwarf strain. If we plant them in a 100% even field with the same nutrients, water, sunlight, etc at every point in the field, then close to 100% of the variation in the resulting corn plants is genetic (some is just random chance, of course.)

In this population, then, height is nearly 100% heritable.

Let’s repeat the experiment, but this time, we sow our corn in an irregular field. Some patches have good soil; some have bad. Some spots are too dry or too wet. Some are sunny; others shaded. Etc.

Here it gets interesting, because aside from a bit of random chance in the distribution of seeds and environmental response, in most areas of the irregular field, our “tall” corn is still taller than the “short” corn. In the shady areas, both varieties don’t get enough sun, but the tall corn still grows taller. In the nutrient-poor areas, both varieties don’t get enough nutrients, but the tall still grows taller. But when we compare all of the corn all over the field, dwarf corn grown in the best areas grows taller than giant corn grown in the worst areas.

Our analysis of the irregular field leads us to conclude that water, sunlight, nutrients, and genes are all important in determining how tall corn gets.

Height in the irregular field is still heritable–genes are still important–but it is not 100% heritable, because other stuff is important, too.

What does it mean to be 10, 40, or 80% heritable?

If height is 10% heritable, then most of the variety in height you see is due to non-genetic factors, like nutrition. Genes still have an effect–people with tall genes will still, on average, be taller–but environmental effects really dominate–perhaps some people who should have been tall are severely malnourished.

In modern, first world countries, height is about 80% heritable–that is, since most people in first world countries get plenty of food and don’t catch infections that stunt their growth, most of the variation we see is genetic. In some third world countries, however, the heritability of height drops to 65%. These are places where many people do not get the nutrients they need to achieve their full genetic potential.

How do you achieve 0% heritability?

A trait is 0% heritable not if you can’t inherit it, but if genetics explains none of the variation in the sample. Suppose we seeded an irregular field entirely with identical, cloned corn. The height of the resulting corn would would vary from area to area depending on nutrients, sunlight, water, etc. Since the original seeds were 100% genetically identical, all of the variation is environmental. Genes are, of course, important to height–if the relevant genes disappeared from the corn, it would stop growing–but they explain none of the variation in this population.

The heritability of a trait decreases, therefore, as genetic uniformity increases or the environment becomes more unequal. Heritability increases as genetics become more varied or the environment becomes more equal. 

Note that the genes involved do not need to code directly for the trait being measured. The taller people in a population, for example, might have lactase persistence genes, which let them extract more calories from the milk they drink than their neighbors. Or they might be thieves who steal food from their neighbors.

I remember a case where investigators were trying to discover why most of the boys at an orphanage had developed pellagra, then a mystery disease, but some hadn’t. It turns out that the boys who hadn’t developed it were sneaking into the kitchen at night and stealing food.

Pellagra is a nutritional deficiency caused by lack of niacin, aka B3. Poor Southerners used to come down with it from eating diets composed solely of (un-nixtamalized) corn for months on end.

The ultimate cause of pellagra is environmental–lack of niacin–but who comes down with pellagra is at least partially determined by genes, because genes influence your likelihood of eating nothing but corn for 6 months straight. Sociopaths who steal the occasional ham, for example, won’t get pellagra, but sociopaths who get caught and sent to badly run prisons, however, increase their odds of getting it. In general, smart people who work hard and earn lots of money significantly decrease their chance of getting it, but smart black people enslaved against their will are more likely to get it. So pellagra is heritable–even though it is ultimately a nutritional deficiency.

What’s the point of heritability?

If you’re breeding corn (or cattle,) it helps to know whether, given good conditions, you can hope to change a trait. Traits with low heritability even under good conditions simply can’t be affected very much by breeding, while traits with high heritability can.

In humans, heritability helps us seek out the ultimate causes of diseases. On a social level, it can help measure how fair a society is, or whether the things we are doing to try to make society better are actually working.

For example, people would love to find a way to make children smarter. From Baby Einstein to HeadStart, people have tried all sorts of things to raise IQ. But beyond making sure that everyone has enough to eat, no nutrient deficiencies, and some kind of education, few of these interventions seem to make much difference.

Here people usually throw in a clarification about the difference between “shared” and “non-shared” environment. Shared environment is stuff you share with other members of your population, like the house your family lives in or the school you and your classmates attend. Non-shared is basically “random stuff,” like the time you caught meningitis but your twin didn’t.

Like anything controversial, people of course argue about the methodology and mathematics of these studies. They also argue about proximate and ultimate causes, and get caught up matters of cultural variation. For example, is wearing glasses heritable? Some would say that it can’t be, because how can you inherit a gene that somehow codes for possessing a newly invented (on the scale of human evolutionary history) object?

But this is basically a fallacy that stems from mixing up proximate and ultimate causes. Obviously there is no gene that makes a pair of glasses grow out of your head, nor one that makes you feel compelled to go and buy them. It is also obvious that not all human populations throughout history have had glasses. But within a population that does have glasses, the chances of you wearing glasses is strongly predicted by whether or not you are nearsighted, and nearsightedness is a remarkable 91% heritable. 

Of course, some nearsighted people opt to wear contact lenses, which lowers the heritability estimate for glasses, but the signal is still pretty darn strong, since almost no one who doesn’t have vision difficulties wears glasses.

If we expand our sample population to include people who lived before the invention of eyeglasses, or who live in countries where most people are too poor to afford glasses, then our heritability estimate will drop quite a bit. You can’t buy glasses if they don’t exist, after all, no matter how bad your eyesight it. But the fact that glasses themselves are a recent artifact of particular human cultures does not change the fact that, within those populations, wearing glasses is heritable.

“Heritability” does not depend on whether there is (or we know of ) any direct mechanism for a gene to code for the thing under study. It is only a statistical measure of genetic variation that correlates with the visible variation we’re looking at in a population.

I hope this helps.

Book Club: The 10,000 Year Explosion pt 7: Finale

 

Niels Bohr
Niels Bohr: 50% Jewish, 100% Quantum Physics

Chapter 7 of The 10,000 Year Explosion is about the evolution of high Ashkenazi IQ; chapter 8 is the Conclusion, which is just a quick summary of the whole book. (If you’re wondering if you would enjoy the book, try reading the conclusion and see if you want to know more.)

This has been an enjoyable book. As works on human evolution go, it’s light–not too long and no complicated math. Pinker’s The Blank Slate gets into much more philosophy and ethics. But it also covers a lot of interesting ground, especially if you’re new to the subject.

I have seen at least 2 people mention recently that they had plans to respond to/address Cochran and Harpending’s timeline of Jewish history/evolution in chapter 7. I don’t know enough to question the story, so I hope you’ll jump in with anything enlightening.

The basic thesis of Chapter 7 is that Ashkenazi massive over-representation in science, math, billionaires, and ideas generally is due to their massive brains, which is due in turn to selective pressure over the past thousand years or so in Germany and nearby countries to be good at jobs that require intellect. The authors quote the historian B. D. Weinryb:

More children survived to adulthood in affluent families than in less affluent ones. A number of genealogies of business leaders, prominent rabbis, community leaders, and the like–generally belonging to the more affluent classes–show that such people often had four, six, sometimes even eight or nice children who reached adulthood…

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Einstein and Bohr, 1925

Weinryb cites a census of the town of Brody, 1764: homeowner household had 1.2 children per adult; tenant households had only 0.6.

As evidence for this recent evolution, the authors point to the many genetic diseases that disproportionately affect Ashkenazim:

Tay-Sachs disease, Gaucher’s disease, familial dysautonomia, and two different forms of hereditary breast cancer (BRCA1 and BRCA2), and these diseases are up to 100 times more common in Ashkenazi Jews than in other European populations. …

In principle, absent some special cause, genetic diseases like these should be rare. New mutations, some of which have bad effects, appear in every generation, but those that cause death or reduced fertility should be disappearing with every generation. … one in every twenty-five Ashkenazi Jews carries a copy of the Tay-Sachs mutation, which kills homozygotes in early childhood. This is an alarming rate.

What’s so special about these diseases, and why do the Ashkenazim have so darn many of them?

Some of them look like IQ boosters, considering their effects on the development of the central nervous system. The sphingolipid mutations, in particular, have effects that could plausibly boost intelligence. In each, there is a buildup of some particular sphingolipid, a class of modified fat molecules that play a role in signal transmission and are especially common in neural tissues. Researchers have determined that elevated levels of those sphingolipids cause the growth of more connections among neurons..

There is a similar effect in Tay-Sachs disease: increased levels of a characteristic storage compound… which causes a marked increase in the growth of dendrites, the fine branches that connect neurons. …

We looked at the occupations of patients in Israel with Gaucher’s disease… These patients are much more likely to be engineers or scientists than the average Israeli Ashkenazi Jew–about eleven times more likely, in fact.

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Einstein and Oppenheimer, Father of the Atomic Bomb, c. 1950

Basically, the idea is that similar to sickle cell anemia, being heterozygous for one of these traits may make you smarter–and being homozygous might make your life considerably shorter. In an environment where being a heterozygous carrier is rewarded strongly enough, the diseases will propagate–even if they incur a significant cost.

It’s a persuasive argument.

I’d like to go on a quick tangent to Von Neumann’s Wikipedia page:

Von Neumann was a child prodigy. When he was 6 years old, he could divide two 8-digit numbers in his head [14][15] and could converse in Ancient Greek. When the 6-year-old von Neumann caught his mother staring aimlessly, he asked her, “What are you calculating?”[16]

Children did not begin formal schooling in Hungary until they were ten years of age; governesses taught von Neumann, his brothers and his cousins. Max believed that knowledge of languages in addition to Hungarian was essential, so the children were tutored in English, French, German and Italian.[17] By the age of 8, von Neumann was familiar with differential and integral calculus,[18] but he was particularly interested in history. He read his way through Wilhelm Oncken‘s 46-volume Allgemeine Geschichte in Einzeldarstellungen.[19] A copy was contained in a private library Max purchased. One of the rooms in the apartment was converted into a library and reading room, with bookshelves from ceiling to floor.[20]

JohnvonNeumann-LosAlamos
Von Neumann

Von Neumann entered the Lutheran Fasori Evangélikus Gimnázium in 1911. Wigner was a year ahead of von Neumann at the Lutheran School and soon became his friend.[21] This was one of the best schools in Budapest and was part of a brilliant education system designed for the elite. Under the Hungarian system, children received all their education at the one gymnasium. Despite being run by the Lutheran Church, the school was predominately Jewish in its student body [22] The school system produced a generation noted for intellectual achievement, which included Theodore von Kármán (b. 1881), George de Hevesy (b. 1885), Leó Szilárd (b. 1898), Dennis Gabor (b. 1900), Eugene Wigner (b. 1902), Edward Teller (b. 1908), and Paul Erdős (b. 1913).[23] Collectively, they were sometimes known as “The Martians“.[24] 

One final thing in The 10,000 Year Explosion jumped out at me:

There are also reports of individuals with higher-than-average intelligence who have nonclassic congenital adrenal hyperplasia (CAH)… CAH, which causes increased exposure of the developing fetus to androgens (male sex hormones), is relatively mild compared to diseases like Tay-Sachs. At least seven studies show high IQ in CAH patients, parents, and siblings, ranging from 107 to 113. The gene frequency of CAH among the Ashkenazim is almost 20 percent.

Holy HBD, Batman, that’ll give you a feminist movement.

If you haven’t been keeping obsessive track of who’s who in the feminist movement, many of the early pioneers were Jewish women, as discussed in a recent article by the Jewish Telegraph Agency, “A History of the Radical Jewish Feminists and the one Subject they Never Talked About“:

Heather Booth, Amy Kesselman, Vivian Rothstein and Naomi Weisstein. The names of these bold and influential radical feminists may have faded in recent years, but they remain icons to students of the women’s liberation movement …

The Gang of Four, as they dubbed themselves, were among the founders of Chicago’s Women’s Liberation Union. …

Over weeks, months and years, no subject went unturned, from the political to the sexual to the personal. They were “ready to turn the world upside down,” recalled Weisstein, an influential psychologist, neuroscientist and academic who died in 2015.

But one subject never came up: the Jewish backgrounds of the majority of the group.

“We never talked about it,” Weisstein said.

Betty Friedan was Jewish; Gloria Steinem is half Jewish. There are a lot of Jewish feminists.

Of course, Jews are over-represented in pretty much every intellectual circle. Ayn Rand, Karl Marx, and Noam Chomsky are all Jewish. Einstein and Freud were Jewish. I haven’t seen anything suggesting that Jews are more over-represented in feminism than in any other intellectual circle they’re over-represented in. Perhaps they just like ideas. Someone should come up with some numbers.

Here’s a page on Congenital Adrenal Hyperplasia. The “classic” variety is often deadly, but the non-classic (the sort we are discussing here) doesn’t kill you.

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Paul Erdős with Terrence Tao, 1984 (Tao isn’t Jewish, of course.)

I’ve long suspected that I know so many trans people because some intersex conditions result in smarter brains (in this case, women who are better than average at math.) It looks like I may be on the right track.

Well, that’s the end of the book. I hope you enjoyed it. What did you think? And what should we read next? (I’m thinking of doing Pinker’s Blank Slate.)

Book Club: The 10,000 Year Explosion pt. 6: Expansion

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Welcome back to the Book Club. Today we’re discussing chapter 6 of Cochran and Harpending’s The 10,000 Year Explosion: Expansions

The general assumption is that the winning advantage is cultural–that is to say, learned. Weapons, tactics, political organization, methods of agriculture: all is learned. The expansion of modern humans is the exception to the rule–most observers suspect that biological difference were the root cause of their advantage. … 

the assumption that more recent expansions are all driven by cultural factors is based on the notion that modern humans everywhere have essentially the same abilities. that’s a logical consequence of human evolutionary stasis” If humans have not undergone a significant amount of biological change since the expansion out of Africa, then people everywhere would have essentially the same potentials, and no group would have a biological advantage over its neighbors. But as we never tire of pointing out, there has been significant biological change during that period.

I remember a paper I wrote years ago (long before this blog) on South Korea’s meteoric economic rise. In those days you had to actually go to the library to do research, not just futz around on Wikipedia. My memory says the stacks were dimly lit, though that is probably just some romanticizing. 

I poured through volumes on 5 year economic plans, trying to figure out why South Korea’s were more successful than other nations’. Nothing stood out to me. Why this plan and not this plan? Did 5 or 10 years matter? 

I don’t remember what I eventually concluded, but it was probably something along the lines of “South Korea made good plans that worked.” 

People around these parts often criticize Jared Diamond for invoking environmental explanations while ignoring or directly counter-signaling their evolutionary implications, but Diamond was basically the first author I read who said anything that even remotely began to explain why some countries succeeded and others failed. 

Environment matters. Resources matter. Some peoples have long histories of civilization, others don’t. Korea has a decently long history. 

Diamond was one of many authors who broke me out of the habit of only looking at explicit things done by explicitly recognized governments, and at wider patterns of culture, history, and environment. It was while reading Peter Frost’s blog that I first encountered the phrase “gene-culture co-evolution,” which supplies the missing link. 

800px-National_IQ_per_country_-_estimates_by_Lynn_and_Vanhanen_2006
IQ by country

South Korea does well because 1. It’s not communist and 2. South Koreans are some of the smartest people in the world. 

I knew #1, but I could have saved myself a lot of time in the stacks if someone had just told me #2 instead of acting like SK’s economic success was a big mystery. 

The fact that every country was relatively poor before industrialization, and South Korea was particularly poor after a couple decades of warfare back and forth across the peninsula, obscures the nation’s historically high development. 

For example, the South Korean Examination system, Gwageo, was instituted in 788 (though it apparently didn’t become important until 958). Korea has had agriculture and literacy for a long time, with accompanying political and social organization. This probably has more to do with South Korea having a relatively easy time adopting the modern industrial economy than anything in particular in the governments’ plans. 

Cochran has an interesting post on his blog on Jared Diamond and Domestication: 

In fact, in my mind the real question is not why various peoples didn’t domesticate animals that we know were domesticable, but rather how anyone ever managed to domesticate the aurochs. At least twice. Imagine a longhorn on roids: they were big and aggressive, favorites in the Roman arena. … 

The idea is that at least some individual aurochs were not as hostile and fearful of humans as they ought to have been, because they were being manipulated by some parasite. … This would have made domestication a hell of a lot easier. …

The beef tape worm may not have made it through Beringia.  More generally, there were probably no parasites in the Americas that had some large mammal as intermediate host and Amerindians as the traditional definite host. 

They never mentioned parasites in gov class. 

Back to the book–I thought this was pretty interesting:

One sign of this reduced disease pressure is the unusual distribution of HLA alleles among Amerindians. the HLA system … is a group of genes that encode proteins expressed on the outer surfaces of cells. the immune system uses them to distinguish the self from non-self… their most important role is in infections disease. … 

HLA genes are among the most variable of all genes. … Because these genes are so variable, any two humans (other than identical twins) are almost certain to have a different set of them. … Natural selection therefore favors diversification of the HLA genes, and some alleles, though rare, have been persevered for a long time. In fact, some are 30 million years old, considerably older than Homo sapiens. …

But Amerindians didn’t have that diversity. Many tribes have a single HLA allele with a frequency of over 50 percent. … A careful analysis of global HLA diversity confirms continuing diversifying selection on HLA in most human populations but finds no evidence of any selection at all favoring diversity in HLA among Amerindians.

The results, of course, went very badly for the Indians–and allowed minuscule groups of Spaniards to conquer entire empires. 

The threat of European (and Asian and African) diseases wiping out native peoples continues, especially for “uncontacted” tribes. As the authors note, the Surui of Brazil numbered 800 when contacted in 1980, but only 200 in 1986, after tuberculosis had killed most of them. 

…in 1827, smallpox spared only 125 out of 1,600 Mandan Indians in what later became North Dakota.

The past is horrific. 

I find the history ancient exploration rather fascinating. Here is the frieze in Persepolis with the okapi and three Pygmies, from about 500 BC.

The authors quote Joao de Barros, a 16th century Portuguese historian: 

But it seems that for our sins, or for some inscrutable judgment of God, in all the entrances of this great Ethiopia we navigate along… He has placed a striking angel with a flaming sword of deadly fevers, who prevents us from penetrating into the interior to the springs of this garden, whence proceed these rivers of gold that flow to the sea in so many parts of our conquest.

Barros had a way with words. 

It wasn’t until quinine became widely available that Europeans had any meaningful success at conquering Africa–and even still, despite massive technological advantages, Europeans haven’t held the continent, nor have they made any significant, long-term demographic impact. 

EX-lactoseintolerance
Source: National Geographic

The book then segues into a discussion of the Indo-European expansion, which the authors suggest might have been due to the evolution of a lactase persistence gene. 

(Even though we usually refer to people as “lactose intolerance” and don’t regularly refer to people as “lactose tolerant,” it’s really tolerance that’s the oddity–most of the world’s population can’t digest lactose after childhood.

Lactase is the enzyme that breaks down lactose.)

Since the book was published, the Indo-European expansion has been traced genetically to the Yamnaya (not to be confused with the Yanomamo) people, located originally in the steppes north of the Caucasus mountains. (The Yamnaya and Kurgan cultures were, I believe, the same.) 

An interesting linguistic note: 

Uralic languages (the language family containing Finnish and Hungarian) appear to have had extensive contact with early Indo-European, and they may share a common ancestry. 

I hope these linguistic mysteries continue to be decoded. 

The authors claim that the Indo-Europeans didn’t make a huge genetic impact on Europe, practicing primarily elite dominance–but on the other hand, A Handful of Bronze-Age Men Could Have Fathered 2/3s of Europeans:

In a new study, we have added a piece to the puzzle: the Y chromosomes of the majority of European men can be traced back to just three individuals living between 3,500 and 7,300 years ago. How their lineages came to dominate Europe makes for interesting speculation. One possibility could be that their DNA rode across Europe on a wave of new culture brought by nomadic people from the Steppe known as the Yamnaya.

That’s all for now; see you next week.

Book Club: The 10,000 Year Explosion, Part 3

940px-Centres_of_origin_and_spread_of_agriculture.svg
The spread of agriculture

Welcome back to the Book Club. Today we’re reading Chapter 3: Agriculture, from Cochran and Harpending’s The 10,000 Year Explosion: How Civilization Accelerated Human Evolution.

One of my fine readers asked for “best of” recommendations for Cochran and Harpending’s blog, West Hunter. This is a good question, and as I have not yet found a suitable list, I thought I would make my own.

However, the West Hunter is long, so I’m only doing the first year for now:

My friend the Witch Doctor:

Only a handful of Herero shared my skepticism about witchcraft. People in the neighborhood as well as several other employees were concerned about Kozondo’s problem. They told me that he had to be taken to a well known local witch doctor. “Witch doctor” I said, “you all have been watching too many low budget movies. We call them traditional healers these days, not witch doctors”. They all, including Kozondo, would have none of it. “They are bad and very dangerous people, not healers” he said. It quickly became apparent that I was making a fool of myself trying to explain why “traditional healer” was a better way to talk than “witch doctor”. One of our group had some kind of anti-anxiety medicine. We convinced Kozondo to try one but it had no effect at all. Everyone agreed that he must consult the witch doctor so we took him. …

That evening we had something like a seminar with our employees and neighbors about witchcraft. Everyone except the Americans agreed that witchcraft was a terrible problem, that there was danger all around, and that it was vitally important to maintain amicable relations with others and to reject feelings of anger or jealousy in oneself. The way it works is like this: perhaps Greg falls and hurts himself, he knows it must be witchcraft, he discovers that I am seething with jealousy of his facility with words, so it was my witchcraft that made him fall. What is surprising is that I was completely unaware of having witched him so he bears me no ill will. I feel bad about his misfortune and do my best to get rid of my bad feelings because with them I am a danger to friends and family. Among Herero there is no such thing as an accident, there is no such thing as a natural death, witchcraft in some form is behind all of it. Did you have a gastrointestinal upset this morning? Clearly someone slipped some pink potion in the milk. Except for a few atheists there was no disagreement about this. Emotions get projected over vast distances so beware.

Even more interesting to us was the universal understanding that white people were not vulnerable to witchcraft and could neither feel it nor understand it. White people literally lack a crucial sense, or part of the brain. An upside, I was told, was that we did not face the dangers that locals faced. On the other hand our bad feelings could be projected so as good citizens we had to monitor carefully our own “hearts”.

Amish Paradise:

French Canadian researchers have shown that natural selection has noticeably sped up reproduction among the inhabitants of Île aux Coudres, an island in the St. Lawrence River –  in less than 150 years. Between 1799 and 1940, the age at which women had their first child dropped from 26 to 22, and analysis shows this is due to genetic change.

… Today the French of Quebec must  differ significantly (in those genes that influence this trait)  from people in France, which has had relatively slow population growth.  …

The same must be the case for old American types whose ancestors – Puritans, for example – arrived early and went through a number of high-fertility generations in colonial days.  It’s likely the case for the Mormons, who are largely descended from New Englanders. I’ve heard of odd allele frequencies  in CEU  (involving FSH) that may relate to this.

Something similar must be true of the Boers as well.

I would guess that a similar process operated among the first Amerindians that managed to get past  the ice in North America.  America south of the glaciers would have been a piece of cake for anyone tough enough to make a living as a hunter in Beringia – lush beyond belief, animals with no experience of humans.

Six Black Russians:

(Black Russians are, I think, an alcoholic beverage.)

Every now and then, I notice someone, often an anthropologist,  saying that human cognitive capability just has to be the same in all populations.  According to Loring Brace, “Human cognitive capacity , founded on the ability to learn a language, is of equal survival value to all human groups, and consequently there is no valid reason to expect that there should be average differences in intellectual ability among living human populations. ”

There are a lot of ideas and assumptions in that quote, and as far as I can tell, all of them are wrong.  …

Populations vary tremendously in the fraction that contributes original work in science and technology – and that variation mostly agrees with the distribution of IQ.

And Your Little Dog, Too!

As I have mentioned before,  the mtDNA of European hunter-gathers seems to be very different from that of modern Europeans. The ancient European mtDNA pool was about 80% U5b – today that lineage is typically found at 10% frequency or lower, except in northern Scandinavia. Haplogroup H, currently the most common in Europe, has never been found in early Neolithic or  pre-Neolithic Europeans.  …

Interestingly, there is a very similar  pattern in canine mtDNA.  Today Europeans dogs fall into four haplotypes: A (70%), B(16%), C (6%), and D(8%).  But back in the day, it seems that the overwhelming majority of dogs (88%)  were type C,  12% were in group A, while B and D have not been detected at all.

Lewontin’s Argument 

(always bears re-addressing)

Richard Lewontin argued that since most (> 85%) genetic variation in humans is within-group, rather than between groups, human populations can’t be very different. Of course, if this argument is valid, it should apply to any genetically determined trait. Thus the  variation in skin color within a population should be larger than the skin color differences between populations – except that it’s not. The difference in skin color between Europeans and Pygmies is large, so large that there is no overlap at all.

The Indo-European Advantage

There is a large region of homogeneity on European haplotypes with the mutation [for lactose tolerance], telling us that it has arisen to high frequency within the last few thousand years. …

In a dairy culture where fresh milk was readily available, children who could drink it obtained about 40% more calories from milk than children who were not LT.

Consider that 1 Liter of cow’s milk has

* 250 Cal from lactose
* 300 Cal from fat
* 170 Cal from protein

or 720 Calories per liter. But what if one is lactose intolerant? Then no matter whether or not flatulence occurs that person does not get the 250 Calories of lactose from the liter of milk, but only gets 470.

The Hyperborean Age

I was contemplating Conan the Barbarian, and remembered the essay that Robert E. Howard wrote about the  background of those stories – The Hyborian Age.  I think that the flavor of Howard’s pseudo-history is a lot more realistic than the picture of the human past academics preferred over the past few decades. …

Given the chance (sufficient lack of information), American anthropologists assumed that the Mayans were peaceful astronomers. Howard would have assumed that they were just another blood-drenched snake cult: who came closer? …

Most important, Conan, unlike the typical professor, knew what was best in life.

Class, Caste, and Genes: 

If there is any substantial heritability of merit, where merit is whatever leads to class mobility, then mobility ought to turn classes into hereditary castes surprisingly rapidly.

A start at looking into genetic consequences of meritocracy is to create the simplest possible model and follow its implications. Consider free meritocracy in a two class system, meaning that each generation anyone in the lower class who has greater merit than someone in the upper class immediately swaps class with them. …

Back to the book. Chapter 3: Agriculture: The Big Change

This chapter’s thesis is the crux of the book: agriculture simultaneously exposed humans to new selective pressured and allowed the human population to grow, creating a greater quantity of novel mutations for natural selection to work on.

Sixty thousand years ago, before the expansion out of Africa, there were something like a quarter of a million modern humans. By the Bronze Age, 3,000 years ago that number was roughly 60 million. 

Most random mutations fall somewhere between “useless” and “kill you instantly,” but a few, like lactase persistence, are good. I’m just making up numbers, but suppose 1 in 100 people has good, novel mutation. If your group has 100 people in it (per generation), then you get one good mutation. If your group has 1,000 people, then you get 10 good mutations.

Evolution isn’t like getting bitten by a radioactive spider–it can only work on the genetic variation people actually have. More genetic variation=more chances at getting a good gene that helps people survive.

Or to put it another way, we can look at a population and use “time” as one of our dimensions. Imagine a rectangle of people–all of the people in a community, over time–100 people in the first generation, 100 in the second, etc. After enough time, (10 generations or about 200 years,) you will have 1,000 people and of course hit 10 favorable mutations.

Increasing the population per generation simply increases the speed with which you get those 10 good mutations.

Interestingly:

One might think that it would take much longer for a favorable mutation to spread through such a large population than it would for one to spread through a population as small as the one that existed in the Old Stone Ag. But sine the frequency of an advantageous allele increases exponentially with time in a well-mixed population, rather like the flu, it takes only twice as long to spread through a population of 100 million as it does to spread through a population of 10,000.

The authors note that larger populations can generate more good, creative ideas, not just genes.

Agriculture–and its attendant high population densities–brought about massive cultural changes to human life, from the simple fact of sedentism (for non-pastoralists) to the ability to store crops for the winter, build long-term housing, and fund governments, which in turn created and enforced laws which further changed how humans lived and interacted. 

(Note: “government” pre-dates agriculture, but was rather different when people had no surplus grain to take as taxes.)

Agriculture also triggered the spread of plagues, as people now lived in groups large (and often squalid) enough to breed and transmit them. Related: Evidence for the Plague in Neolithic Farmers’ Teeth.

Plagues have been kind of a big deal in the history of civilization.

On government:

Combined with sedentism, these developments eventually led to the birth of governments, which limited local violence. Presumably, governments did this because it let them extract more resources from their subjects…

Peasants fighting among themselves interferes with the economy. Governments don’t like it and will tend to hang the people involved.

Some people call it self-domestication.

Recent studies have found hundreds of ongoing [genetic] sweeps–sweeps begun thousands of years ago that are still in progress today. Some alleles have gone to fixation, more have intermediate frequencies, and most are regional. Many are very recent: the rate of origination peaks at around 5,000 years ago in the European and Chinese samples, and about 8,500 years ago in the African sample.

I assume that these genes originating about 5,000 years ago are mostly capturing the Indo-European (pastoralist) and Anatolian (farming) expansions. I don’t know what happened in China around 5,000 years ago, but I wouldn’t be surprised if whatever triggered the Indo-Europeans to start moving in central Asia were connected with events further to the east.

IIRC, 8,500 years ago is too early for the Bantu expansion in Africa, so must be related to something else.

There is every reason to think that early farmers developed serious health problems from this low-protein, vitamin -short, high-carbohydrate diet. Infant mortality increased, and the poor diet was likely one of the causes. you can see the mismatch between the genes and the environment in the skeletal evidence Humans who adopted agriculture shrank: average height dropped  by almost five inches.

I have seen this claim many times, and still find it incredible. I am still open to the possibility of it having been caused by a third, underlying factor, like “more people surviving diseases that had formerly killed them.”

There are numerous signs of pathology in the bones of early agriculturalists. In the Americas, the introduction of maize led to widespread tooth decay and anemia due to iron deficiency…

Of course, over time, people adapted to their new diets. You are not a hunter-gatherer. (Probably. If you are, hello!)

…Similarly, vitamin D shortages in the new die may have driven the evolution of light skin in Europe and northern Asia. Vitamin D is produced by ultraviolet radiation from the sun acting on our skin… Since there is plenty of vitamin D in fresh meat, hunter-gatherers in Europe may not have suffered from vitamin D shortages and thus may have been able to get by with fairly dark skin. In fact, this must have been the case, since several of the major mutations causing light skin color appear to have originated after the birth of agriculture. vitamin D was not abundant in the new cereal-based diet, and any resulting shortages would have been serious, since they could lead to bone malformations (rickets,) decreased resistance to infectious diseases, and even cancer. …

I have read that of the dark-skinned peoples who have recently moved to Britain, the vegetarians among them have been the hardest-hit by vitamin D deficiency. Meat is protective. 

Peoples who have farmed since shortly after the end of the Ice Age (such as the inhabitants of the Middle East) must have adapted most thoroughly to agriculture. In areas where agriculture is younger, such as Europe or China, we’d expect to see fewer adaptive changes… In groups that had remained foragers, there would presumably be no such adaptive changes…

Populations that have never farmed or that haven’t farmed for long, such as the Australian Aborigines and many Amerindians, have characteristic health problems today when exposed to Western diets.

EG, Type 2 diabetes.

Dr. (of dentistry) Weston Price has an interesting book, Nutrition and Physical Degeneration, that describes people Price met around the world, their dental health, and their relationship to Western or traditional diets. (Written/published back in the 1930s.) I’m a fan of the book; I am not a fan of the kind of weird organization that publishes it. That organization promotes fringe stuff like drinking raw milk, but as far as I can recall, I didn’t see anything about drinking raw milk in the entirety of Dr. Price’s tome; Dr. Price wasn’t pushing anything fringe, but found uncontroversial things like “poverty-stricken children during the Great Depression did better in school when given nutritious lunches.” Price was big on improper nutrition as the cause of tooth decay and was concerned about the effects of industrialization and Western diets on people’s bones and teeth.

So we’ve reached the end of Chapter 3. What did you think? Do you agree with Greg and Henry’s model of how Type 2 Diabetes arises, or with the “thrifty genotype” promulgated by James Neel? And why do metabolic syndromes seem to affect poor whites more than affluent ones?

What about the higher rates of FAS among African Americans than the French (despite the French love of alcohol) or the straight up ban on alcohol in many Islamic (ancient farming) cultures? What’s going on there?

And any other thoughts you want to add.

See you next Wednesday for chapter 4.

Finnis, Saami, and Fennoscandian DNA

 

800px-Lenguas_finougrias
Distribution of the Finno-Ugric languages

I’ve long wondered which group arrived first in Europe: the Indo-Europeans or the Finno-Ugrics. Most Europeans speak one of the hundreds of languages in the Indo-European family tree, but a few groups speak languages from the mostly Siberian Finno-Ugric branch of the Uralic family.

(Sorry, guys, I’m out of practice writing and these sentences don’t sound good to me, but the only way to improve is to forge ahead, so let’s go.)

Major countries/ethnic groups that speak Finno-Ugric languages include the Finns (obviously,) Saami/Lapps, Hungarians, and Estonians. The most southerly of this family, Hungarian, arrived in the Carpathian Basin within the span of recorded History (in 894 or 895, followed by a few years of warfare to secure their territory,) but the origins of the other European Finno-Ugric languages remains mysterious.

Who arrived first, the Indo Europeans or the Finns? Did the Saami always live in their current homelands, or did they once range much further south or east? Did they migrate here recently or long ago (since the entire area was under ice sheets during the ice age, no one lived there tens of thousands of years ago.)

With the exception of Hungarian, these languages all hail from the far north (especially if you include the Samoyidic languages, which hail from north of Komi on the map,) a cold and forbidding land where herding, hunting, gathering, and fishing have remained the primary way of life until quite recently–the long winters making agriculture very difficult.

Lamnidis et al have a new paper out on Ancient Fennoscandian DNA that sheds a fascinating light on the subject:

Here we analyse ancient genomic data from 11 individuals from Finland and north-western Russia. We show that the genetic makeup of northern Europe was shaped by migrations from Siberia that began at least 3500 years ago. This Siberian ancestry was subsequently admixed into many modern populations in the region, particularly into populations speaking Uralic languages today. Additionally, we show that ancestors of modern Saami inhabited a larger territory during the Iron Age, which adds to the historical and linguistic information about the population history of Finland.

41467_2018_7483_fig1_htmlLet’s cut to the pictures, because they are worth a thousand words:

Just in case you are unclear on the geography, the Modern Saami come from northern part of the Finnoscandian peninsula. Six of the ancient remains came from Bolshoy Oleni Ostrov in the Murmansk Region on the Kola Peninsula–that’s the topmost dot on the map, now in Russia. These remains are very old–dated to about 1610-1436 BC.

Seven remains came from Levänluhta in Isokyrö, Finland, from a more recent burial dated to around 300-800 AD. (Actually, I think Levanluhta is a lake, so  This is the most southwestern burial on the map, in an area where the modern Finns live.

And the remains of two people came from a much more recent Saami cemetery in the Kola peninsula, Chalmny Varre, dating from the 17 or 1800s.

All of this DNA was compared against a variety of reference populations:

41467_2018_7483_fig2_html

(I would just like to pause for a moment to appreciate both the beauty and hard work that went into these graphs.)

PC2 graphs are a little complicated, but what we’re basically looking at (in color) are two different human population axes. They very roughly correlate to north-south (up and down) and east-west, (left to right), because people tend to be more closely related to their neighbors than people thousands of miles away, but there’s another, more fascinating story going on here.

On the right-hand side, we have a cline that maps very nicely to north and south, from the Yukagir–a people from a part of Russia that’s so far to the northeast it’s almost in Alaska–at the top and the Semende of Indonesia and the Atayal, an indigenous Taiwanese group, at the bottom. (Most Taiwanese you meet are either newly arrived Han Chinese or older Han Chinese; the aboriginal Taiwanese are different, but likely the ancestors of Polynesians.)

AsianDNA1
DNA from various Asian peoples

Most east Asian DNA shows up as a blend of these two groups (which we may call roughly polar and tropical). In the chart to the right, taken from Haak et al, the polar DNA is red and the tropical is yellow. So the up-down cline on the right side of the map represents which particular mix of Polar/Tropical DNA these folks have.

On the left side of the graph, we have a farming/hunter-gatherer cline. The first farmers hailed from Anatolia (now Turkey, but that was before the Turks moved to Turkey,) and subsequently spread/conquered most of Europe and probably a few other places, because agriculture was quite successful. So the orange is Middle Easterners; above them are southern Europeans like Albanians and Basques; then the English, French, Hungarians, Finns, etc; and finally some older burials of people with descriptive names like “Eastern Hunter-Gatherer” [EHG] or “Scandinavian Hunter-gatherers” [SHG].

(I have to constantly remind myself what these little abbreviations mean, but The Genetic Prehistory of the Baltic Region probably clears things up a bit:

Similarly, in the Eastern Baltic, where foraging continued to be the main form of subsistence until at least 4000 calBCE15, ceramics technology was adopted before agriculture, as seen in the Narva Culture and Combed Ceramic Culture (CCC). Recent genome-wide data of Baltic pottery-producing hunter-gatherers revealed genetic continuity with the preceding Mesolithic inhabitants of the same region as well as influence from the more northern EHG21,22, but did not reveal conclusively whether there was a temporal, geographical or cultural correlation with the affinity to either WHG or EHG.

The transition from the Late (Final) Neolithic to the Early Bronze Age (LNBA) is seen as a major transformative period in European prehistory, accompanied by changes in burial customs, technology and mode of subsistence as well as the creation of new cross-continental networks of contact seen in the emergence of the pan-European Corded Ware Complex (CWC, ca. 2900–2300 calBCE) in Central2 and north-eastern Europe21.

If you remember your Guns, Germs, and Steel, Turkish farmers had a really hard time getting their wheat to grow up in really cold places like Northern Russia,  Scandinavia and Narva (near the border between Estonia and Russia on the Baltic Sea,) which is why modern Finland is super poor and Turkey and Mexico, where corn was domesticated, are rich–what it doesn’t quite work like that?

Okay.

Anyway.

So most Europeans today are a mix of Anatolian farmers and various European hunter gatherer groups, with exactly how much you got depending a lot on whether the local environment was hospitable to farming. The pure hunter-gatherer genomes therefore show up as “further north” than the mixed, modern genomes of modern French and British folks.

There were additional events besides the Anatolian conquest that shaped modern European genetics–mostly the aforementioned Indo-European conquest–but the Indo-Europeans were at least part hunter-gatherer by DNA (nomadic pastoralists by profession,) so on this scale, their contributions look a lot like the older hunter-gatherer DNA.

So the interesting part of the graph is the middle, where all of the central Eurasian peoples are plotted. The purple band is various Finno-Ugric/Uralic speakers.

Hungarians are solidly in Europe because the ancient conquering Magyars left behind their language, but not much of their DNA (as we’ve discussed previously.) The Nganasan are one of the most thoroughly Siberian peoples you can imagine; they historically survived by hunting reindeer.

The green swaths (light and dark teal) are mostly Turkic-language speaking peoples; the Turkic peoples originated near Mongolia/Korea and spread out from there, mostly absorbing the DNA of whomever they encountered and passing on their language. The authors have also included Mongolian (which is not in the Turkic language family) in the light green group and some Caucuses groups in the dark teal.

Interestingly, the Yukaghir language (far upper right) is (according to Wikipedia,) potentially in the greater Finno-Ugric/Uralic family:

The relationship of the Yukaghir languages with other language families is uncertain, though it has been suggested that they are distantly related to the Uralic languages, thus forming the putative Uralic–Yukaghir language family.[5]

Based on the genetics, I’d say it looks very likely that the ancestors of Uralic-speaking Nganasan and the Yukagirs were conversing in some sort of mutually intelligible language. Unfortunately, Yukaghir has very few speakers and is likely to die, so there’s not much time to research it.

Finally in the Light Teal we have some groups from Pakistan/Afghanistan, like the Balochi.

(Note that all of the colors used in these studies are arbitrary; DNA doesn’t really have a color.)

So where do our ancient DNA remains fall on this graph?

Today, the Levanluhta site is in Finland, surrounded solidly by Finns (and maybe some random Scandinavians; who knows;) in 300-800 AD, the population was almost identical to modern Saami. So even though Saami and Finns both speak Finno-Ugric languages, the Finns replaces the Saami in this area sometime in the past 1,500 years or so.

One Levanlughta skeleton is an exception–the one marked Levanlughta_B; it is clearly closer to the Finns and English on this graph, but deeper mathematical analysis disputes this conclusion:

One of the individuals from Levänluhta (JK2065/Levänluhta_B) rejects a cladal position with modern Saami to the exclusion of most modern Eurasian populations. This individual also rejects a cladal position with Finns. We analysed low coverage genomes from four additional individuals of the Levänluhta site using PCA (Supplementary Figure 3), confirming the exclusive position of Levänluhta_B compared to all other six individuals (including the four low-coverage individuals) from that site, as is consistent with the ADMIXTURE and qpAdm results. The outlier position of this individual cannot be explained by modern contamination, since it passed several tests for authentication (see Methods) along with all other ancient individuals. However, no direct dating was available for the Levänluhta material, and we cannot exclude the possibility of a temporal gap between this individual and the other individuals from that site.

In other words, it is a mystery.

The remains from Chalmny Varre, which we know was a Saami cemetery, unsurprisingly cluster with the other Saami.

The Bolshoy remains, though, are quite interesting. They are shifted slightly in the direction of the ancient hunter-gatherers (perhaps their descendants, if still around, have mixed a bit with the agriculturalists.) Their physical location is about as far east as the Red Squares (ethnic Russians,) yet the more closely resemble the Mansi or the Selkups. (The modern Mansi live here; the modern Selkups live nearby.)

Getting down to the bar graphs, we see this data presented in a different way.

There are three groups that we can see contributing to most modern Europeans–Farmers, represented by the Orange LBK DNA; exclusively Indo-European, Green, notably not found in the Basque; and hunter-gatherers in Dark Blue. (Note that the ancestors of the Indo-Europeans hailed from the Central Eurasian steppes and so their DNA could have gotten around there, too.)

The modern Saami also have a Purple component to their DNA, which finds its highest expression in the Nganasan of far eastern polar Russia.

So the oldest burials–the Bolshoy–show no agricultural DNA. They are hunter-gatherers+Siberians, with a touch of Indo-European (probably from a steppe population that might have contributed to the Indos as well) and a bit they share with… the Karitiana of Brazil? Well, the Native Americans did descend from Paleo Siberians, so some genetic relatedness is expected.

The more recent burials, which cluster with the modern Saami, all show agricultural DNA–probably due to marrying a few of the local Finns/Russians who carry some agricultural DNA (who are almost genetically identical on this scale) rather than a pure LBK agriculturalist.

Here we see why the one outlier, Levanlughta_B, doens’t group with the Finns, either–modern Finns and Russians have some of that Nganasan-style Siberian DNA (probably from the same process that gifted Finnish/Russian DNA to the Saami), but Levanlughta_B doesn’t. Levanlughta_B looks more like the Baltic BA sample (Baltic Bronze Age.) Perhaps this individual was just a merchant, traveler, or lost–or represents a stage before the modern Finnish population had been produced.

The Finnish population itself is interesting, because it is genetically very similar to the Russian, but obviously speaks a language far more closely related to Saami (Lapp) than anything in the Indo-European tree. While it is therefore likely that the Finns replaced the Saami in the area around Lake Levanlughta, it seems also probable that in the process, they absorbed a large number of Uralic-speaking people. Who conquered (or married) whom? Did an ancient Balto-Slavic population move into what is now Finland, marry the local Saami girls, and adopt their language? Did an ancient Siberian population speaking a Uralic language conquer some ancient group of Russians, take their women, pass on their Uralic language, and later move into Finland and drive out the locals? Or perhaps something even more complicated occurred.

As for the Bolshoy, are they related (closely) to the modern Saami, or are they a group that simply died out?

The paper goes on:

 While the Siberian genetic component presented here [Purple] has been previously described in modern-day populations from the region1,3,9,10, we gain further insights into its temporal depth. Our data suggest that this fourth genetic component found in modern-day north-eastern Europeans arrived in the area before 3500 yBP. It was introduced in the population ancestral to Bolshoy Oleni Ostrov individuals 4000 years ago at latest, as illustrated by ALDER dating using the ancient genome-wide data from the Bolshoy samples. The upper bound for the introduction of this component is harder to estimate. The component is absent in the Karelian hunter-gatherers (EHG)3 dated to 8300–7200 yBP as well as Mesolithic and Neolithic populations from the Baltics from 8300 yBP and 7100–5000 yBP respectively8

Karelia is a region that crosses the border between Finland and Russia, so it is significant that this Siberian component isn’t found in ancient Karelian hunter-gatherers. Of course, the Siberians could have just been further north, however, the authors note that we have archaeological evidence of the spread of the Bolshoy people:

The large Nganasan-related component in the Bolshoy individuals from the Kola Peninsula provides the earliest direct genetic evidence for an eastern migration into this region. Such contact is well documented in archaeology, with the introduction of asbestos-mixed Lovozero ceramics during the second millennium BC50, and the spread of even-based arrowheads in Lapland from 1900 BCE51,52. Additionally, the nearest counterparts of Vardøy ceramics, appearing in the area around 1,600-1,300 BCE, can be found on the Taymyr peninsula, much further to the East51,52. Finally, the Imiyakhtakhskaya culture from Yakutia spread to the Kola Peninsula during the same period24,53. Contacts between Siberia and Europe are also recognised in linguistics. The fact that the Nganasan-related genetic component is consistently shared among Uralic-speaking populations, with the exceptions of absence in Hungarians and presence in the non-Uralic speaking Russians, makes it tempting to equate this genetic component with the spread of Uralic languages in the area.

The authors qualify this with a bit of “it’s complicated; people move around a lot,” but basically it’s People: not pots.

That was an enjoyable read; I look forward to the next paper from these folks.

Book Club: The 10,000 Year Explosion pt. 2: Behavioral Modernity 

 

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Neanderthal skull

Welcome back to EvX’s book club. Today we’re discussing Cochran and Harpending’s The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, chapter 2: The Neanderthal Within.

How did you like the chapter?

Unless I have missed a paper somewhere, this is a remarkable chapter, for The 10,000 Year Explosion was published in 2009, and the first Neanderthal genome showing more overlap with Europeans (and Asians) than Sub-Saharans was published in 2010. Greg and Henry did know of genetic evidence that humans have about 5% admixture from some archaic sister-species, but no one yet had evidence of which species, nor was there popular agreement on the subject. Many scientists still rejected the notion of Sapiens-Neanderthal interbreeding when Cochran and Harpending laid out their bold claim that not only had it happened, but it was a critical moment in human history, jump-starting the cultural cultural effervescence known as behavioral modernity.

Homo sapiens have been around for 300,000 years–give or take a hundred thousand–but for most of that time, we left behind rather few interesting artifacts. As the authors point out, we failed to develop agriculture during the Eemian interglacial (though we managed to develop agriculture at least 7 times, independently, during the current interglacial). Homo sapiens attempted to leave Africa several times before 70,000 years ago, but failed each time, either because they weren’t clever enough to survive in their new environment or couldn’t compete with existing hominins (ie, Neanderthals) in the area.

DBoAOVxWsAAYu6jSapiens’ technology didn’t do much interesting for the first couple hundred thousand years, either. Yet 70,000 years ago, sapiens did manage to leave Africa, displace the Neanderthals, spread into radically new climates, developed long distance trade and art, and eventually agriculture and everything we now enjoy here in the modern world.

According to Wikipedia, behavioral modernity includes:

Burial, fishing, art, self-decoration via jewelry or pigment, bone tools, sharp blades, hearths, multi-part tools, long-distance transportation of important items, and regionally distinct artifacts.

This leaves two important questions re: Cochran and Harpending’s theory. First, when exactly did behavioral modernity emerge, and second, was it a gradual transition or a sudden explosion?

Prehistoric art is tricky to date–and obviously did not always get preserved–but Blombos Cave, South Africa, currently contains our earliest piece, from about 70,000-100,000 years ago. The Blombos art is not figurative–it’s patterns of crosshatched lines–but there’s a fair amount of it. Blombos appears to have been an ochre-processing spot (the art is made with or on pieces of ochre) littered with thousands of leftover scraps. According to Wikipedia:

In 2008 an ochre processing workshop consisting of two toolkits was uncovered in the 100,000-year-old levels at Blombos Cave, South Africa.[3] Analysis shows that a liquefied pigment-rich mixture was produced and stored in the shells of two Haliotis midae (abalone), and that ochre, bone, charcoal, grindstones and hammer-stones also formed a composite part of the toolkits. As both toolkits were left in situ, and as there are few other archaeological remains in the same layer, it seems the site was used primarily as a workshop and was abandoned shortly after the pigment-rich compounds were made. Dune sand then blew into the cave from the outside, encapsulated the toolkits and by happenstance ensured their preservation before the next occupants arrived, possibly several decades or centuries later.

The application or use of the compound is not self-evident. No resins or wax were detected that might indicate it was an adhesive for hafting.

70 beads made from shells with holes drilled in them have also been found at Blombos.

Blombos is interesting, but the “art” is not actually very good–and we can’t say for sure that it was meant as art at all. Maybe the locals were just scraping the rocks to get the ochre off, for whatever purposes.

Indisputable art emerges a little later, around 40,000 years ago–simultaneously, it appears, in Europe, Asia, Australia, and Indonesia. The archaeology of Africa is less well-documented (in part because things just disintegrate quickly in some areas), but the earliest known sub-Saharan figurative art is about 26,000 years old. This art is both more advanced (it actually looks like art) and more abundant than its predecessors–the Sungir burial, dated to around 30,000-34,000 BC, for example, contains over 13,000 beads–a stark contrast to Blombos’s 70.

722px-homo_sapiens_lineage-svgIf a specific event triggered the simultaneous development of figurative art–and other aspects of behavioral modernity–in four different parts of the world, that event would logically have occurred before those groups split up. The timing of our interbreeding with Neanderthals–“In Eurasia, interbreeding between Neanderthals and Denisovans  with modern humans took place several times between about 100,000 and 40,000 years ago, both before and after the recent out-of-Africa migration 70,000 years ago”–is therefore temporaly perfect.

Subsequent back-migration could have then carried the relevant Neanderthal genomes into Africa–for regardless of where or how behavioral modernity started, all humans now have it.

So what do you think? Did we talk the Neanderthals to death? Did we get the gene for talking from the Neanderthals? Did we out-think them? Or did we just carry some disease or parasite that wiped them out? Or did they wipe themselves out via maternal death in labor, due to their enormous skulls?

(As for FOXP2, it appears that the version found in humans and Neanderthals is slightly different, so I find it a little doubtful that we got it from them.)

A couple of interesting quotes:

In several places, most clearly in central and southwestern France and part of northern Spain, we find a tool tradition that lasted from about 35,000 to 28,000 years ago (the Chatelperronian) that appears to combine some of the techniques of the Neanderthals … with those of modern humans. … Most important, there are several skeletons clearly associated with the Chatelperronian industry, and all are Neanderthal. This strongly suggests that there were interactions between the populations, enough that the Neanderthals learned some useful techniques from modern humans.

The smoking gene?

P. D. Evans and his colleagues at the University of Chicago looked at microcephalin (MCPH1), a very unusual gene that regulates brain size. They found that most people today carry a version that is quite uniform, suggesting that it originated recently. At the same time, it is very different from other, more varied versions found  at the same locus in humans today, all of which have many single-nucleotide differences among them. More than that, when there are several different versions of a gene at some locus, we normally find some intermediate versions created by recombination, that is, by chromosomes occasionally breaking and recombining. In the case of the unusual gene (called D for “derived”) at the microcephalin locus, such recombinants are very rare: It is as if the common, highly uniform version of microcephalin simply hasn’t been in the human race all that long in spite of the high frequency of the new version in many human populations. The researchers estimated that it appeared about 37,000 years ago (plus or minus a few tens of thousands of years.) And if it did show up then, Neanderthals are a reasonable, indeed likely, source.

So far as I know (and I looked it up a few weeks ago) no one has yet found microcephalin D in Neanderthals–and the date of 37,000 years ago sounds a bit too recent. However, we haven’t actually genotyped that many Neanderthals (it’s hard to find good 40,000 year old DNA), so we might just not have found it yet–and the date might simply be wrong.

It’s a remarkable genetic finding, even if it didn’t involve Neanderthals–and it might be simpler to dispense with other standards and define Homo sapiens as starting at this point.

On a related note, here’s a bit from Wikipedia about the ASPM gene:

A new allele (version) of ASPM appeared sometime between 14,100 and 500 years ago with a mean estimate of 5,800 years ago. The new allele has a frequency of about 50% in populations of the Middle East and Europe, it is less frequent in East Asia, and has low frequencies among Sub-Saharan African populations.[12] It is also found with an unusually high percentage among the people of Papua New Guinea, with a 59.4% occurrence.[13]

The mean estimated age of the ASPM allele of 5,800 years ago, roughly correlates with the development of written language, spread of agriculture and development of cities.[14] Currently, two alleles of this gene exist: the older (pre-5,800 years ago) and the newer (post-5,800 years ago). About 10% of humans have two copies of the new ASPM allele, while about 50% have two copies of the old allele. The other 40% of humans have one copy of each. Of those with an instance of the new allele, 50% of them are an identical copy.[15] The allele affects genotype over a large (62 kbp) region, a so called selective sweep which signals a rapid spread of a mutation (such as the new ASPM) through the population; this indicates that the mutation is somehow advantageous to the individual.[13][16]

Testing the IQ of those with and without new ASPM allele has shown no difference in average IQ, providing no evidence to support the notion that the gene increases intelligence.[16][17][18] However statistical analysis has shown that the older forms of the gene are found more heavily in populations that speak tonal languages like Chinese or many Sub-Saharan African languages.[19]

We still have so much to discover.

Book Club: The 10,000 Year Explosion pt 1

 

5172bf1dp2bnl-_sx323_bo1204203200_For most of he last century, the received wisdom in the social sciences has been that human evolution stopped a long time ago–in the most up-to-date version, before modern humans expanded out of Africa some 50,000 years ago. This implies that human minds must be the same everywhere–the “psychic unity of mankind.” It would certainly make life simpler if it were true.

Thus Cochran and Harpending fire the opening salvo of  The 10,000 Year Explosion: how Civilization Accelerated Human Evolution. (If you haven’t finished the book yet, don’t worry–we’ll discuss one chapter a week, so you have plenty of time.)

The book’s main thesis–as you can guess by reading the title–is that human evolution did not halt back in the stone age, but has accelerated since then.

I’ve been reading Greg and Henry’s blog for years (now Greg’s blog, since Henry sadly passed away.) If you’re a fan of the blog, you’ll like the book, but if you follow all of the latest human genetics religiously, you might find the book a bit redundant. Still, it is nice to have many threads tied together in one place–and in Greg & Henry’s entertaining style. (I am about halfway through the book as of this post, and so far, it has held up extremely well over the years since it was published.)

Chapter One: Conventional Wisdom explains some of the background science and history necessary to understand the book. Don’t worry, it’s not complicated (though it probably helps if you’ve seen this before.)

A lot of of our work could be called “genetic history.” … This means that when a state hires foreign mercenaries, we are interested in their numbers, their geographic origin, and the extent to which they settled down and mixed with the local population. We don’t much care whether they won their battles, as long as they survived and bred. …

For an anthropologist it might be important to look at how farmers in a certain region and time period lived; for us, as genetic historians, the interesting thing is how natural selection allowed agriculture to come about to begin with, and how the pressures of an agricultural lifestyle allowed changes in the population’s genetic makeup to take root and spread.

One of the things I find fascinating about humans is that the agricultural revolution happened more or less independently in 11 different places, all around 10,000 years ago. There’s a little variation due to local conditions and we can’t be positive that the Indus Valley didn’t have some influence on Mesopotamia and vice versa, but this is a remarkable convergence. Homo sapiens are estimated to have been around for about 200-300,000 years, (and we were predated by a couple million years of other human ancestor-species like Homo erectus)  but for the first 280,000 years or so of our existence no one bothered to invent agriculture. Then in the span of a few thousand years, suddenly it popped up all over the darn place, even in peoples like the Native Americans who were completely isolated from developments over in Asia and Africa.

This suggests to me that some process was going on simultaneously in all of these human populations–a process that probably began back when these groups were united and then progressed at about the same speed, culminating in the adoption of agriculture.

One possibility is simply that humans were hunting the local large game, and about 10,000 years ago, they started running out. An unfortunate climactic event could have pushed people over the edge, reducing them from eating large, meaty animals to scrounging for grass and tubers.

Another possibility is that human migrations–particularly the Out of Africa Event, but even internal African migrations could be sufficient–caused people to become smarter as they encountered new environments, which allowed them to make the cognitive leap from merely gathering food to tending food.

A third possibility, which we will discuss in depth next week, is that interbreeding with Neanderthals and other archaic species introduced new cognitive features to humanity.

And a fourth, related possibility is that humans, for some reason, suddenly developed language and thus the ability to form larger, more complex societies with a division of labor, trade, communication, and eventually agriculture and civilization.

We don’t really know when language evolved, since the process left behind neither bones nor artifacts, but if it happened suddenly (rather than gradually) and within the past 300,000 years or so, I would mark this as the moment Homo sapiens evolved.

While many animals can understand a fair amount of language (dogs, for instance) and some can even speak (parrots,) the full linguistic range of even the most intelligent apes and parrots is still only comparable to a human toddler. The difference between human language abilities and all other animals is stark.

There is great physical variation in modern humans, from Pygmies to Danes, yet we can all talk–even deaf people who have never been taught sign language seek to communicate and invent their own sign language more complex and extensive than that of the most highly trained chimps. Yet if I encountered a group of “humans” that looked just like some of us but fundamentally could not talk, could not communicate or understand language any more than Kanzi the Bonobo, I could not count them members of my species. Language is fundamental.

But just because we can all speak, that does not mean we are all identical in other mental ways–as you well know if you have ever encountered someone who is inexplicably wrong about EVERYTHING here on the internet.

But back to the book:

We intend to make the case that human evolution has accelerated int he past 10,000 years, rather than slowing or stopping, and is now happening about 100 times faster than its long term average over the 6 million years of our existence.

A tall order!

220px-San_tribesman
Some anthropologists refer to Bushmen as “gracile,” which means they are a little shorter than average Europeans and not stockily built

To summarize Cochran and Harpending’s argument: Evolution is static when a species has already achieved a locally-optimal fit with its environment, and the environment is fairly static.

Human environments, however, have not been static for the past 70,000 years or so–they have changed radically. Humans moved from the equator to the polar circle, scattered across deserts and Polynesian islands, adapting to changes in light, temperature, disease, and food along the way.

The authors make a fascinating observation about hunting strategies and body types:

…when humans hunted big game 100,000 years ago, they relied on close-in attacks with thrusting spears. Such attacks were highly dangerous and physically taxing, so in those days, hunters had to be heavily muscled and have thick bones. That kind of body had its disadvantages–if nothing else, it required more food–but on the whole, it was the best solution in that situation. … but new weapons like the atlatl (a spearthrower) and the bow effectively stored muscle-generated energy, which meant that hunters could kill big game without big biceps and robust skeletons. Once that happened, lightly built people, who were better runners and did not need as much food, became competitively superior. The Bushmen of southern Africa…are a small, tough, lean people, less than five feet tall. It seems likely that the tools made the man–the bow begat the Bushmen.

Cro-magnons (now called “European Early Modern Humans” by people who can’t stand a good name,) were of course quite robust, much more so than the gracile Bushmen (Aka San.) Cro-magnons were not unique in their robustness–in fact all of our early human ancestors seem to have been fairly robust, including the species we descended from, such as Homo heidelbergensis and Homo ergaster. (The debate surrounding where the exact lines between human species should be drawn is long and there are no definite answers because we don’t have enough bones.)

We moderns–all of us, not just the Bushmen–significantly less robust than our ancestors. Quoting from a review of Manthropology: The Science of the Inadequate Modern Male:

Twenty thousand years ago six male Australian Aborigines chasing prey left footprints in a muddy lake shore that became fossilized. Analysis of the footprints shows one of them was running at 37 kph (23 mph), only 5 kph slower than Usain Bolt was traveling at when he ran the 100 meters in world record time of 9.69 seconds in Beijing last year. But Bolt had been the recipient of modern training, and had the benefits of spiked running shoes and a rubberized track, whereas the Aboriginal man was running barefoot in soft mud. …

McAllister also presents as evidence of his thesis photographs taken by a German anthropologist early in the twentieth century. The photographs showed Tutsi initiation ceremonies in which young men had to jump their own height in order to be accepted as men. Some of them jumped as high as 2.52 meters, which is higher than the current world record of 2.45 meters. …

Other examples in the book are rowers of the massive trireme warships in ancient Athens who far exceeded the capabilities of modern rowers, Roman soldiers who completed the equivalent of one and a half marathons a day, carrying equipment weighing half their body weight …

McAllister attributes the decline to the more sedentary lifestyle humans have lived since the industrial revolution, which has made modern people less robust than before since machines do so much of the work. …

According to McAllister humans have lost 40 percent of the shafts of the long bones because they are no longer subjected to the kind of muscular loads that were normal before the industrial revolution. Even our elite athletes are not exposed to anywhere near the challenges and loads that were part of everyday life for pre-industrial people.

Long story short: humans are still evolving. We are not static; our bodies do not look like they did 100,000 years ago, 50,000 years ago, nor even 1,000 years ago. The idea that humans could not have undergone significant evolution in 50–100,000 years is simply wrong–dogs evolved from wolves in a shorter time.

Dogs are an interesting case, for despite their wide variety of physical forms, from Chihuahuas to Great Danes, from pugs to huskies, we class them all as dogs because they all behave as dogs. Dogs can interbreed with with wolves and coyotes (and wolves and coyotes with each other,) and huskies look much more like wolves than like beagles, but they still behave like dogs.

The typical border collie can learn a new command after 5 repetitions and responds correctly 95% of the time, whereas a basset hound takes 80-100 repetitions to achieve a 25 percent accuracy rate.

I understand why border collies are smart, but why are bassets so stupid?

Henry and Greg’s main argument depends on two basic facts: First, the speed of evolution–does evolution work fast enough to have caused any significant changes in human populations since we left Africa?

How fast evolution works depends on the pressure, of course. If everyone over 5 feet tall died tomorrow, the next generation of humans would be much shorter than the current one–and so would their children.

The end of the Ice Age also brought about a global rise in sea level. … As the waters rose, some mountains became islands.. These islands were too small to sustain populations of large predators, and in their absence the payoff for being huge disappeared. … Over a mere 5,000 years, elephants shrank dramatically, from an original height of 12 feet to as little as 3 feet.  It is worth noting that elephant generations are roughly twenty years long, similar to those of humans.

We have, in fact, many cases of evolution happening over a relatively short period, from dogs to corn to human skin tone.

No one is arguing about the evolution of something major, like a new limb or an extra spleen–just the sorts of small changes to the genome that can have big effects, like the minor genetic differences that spell the difference between a wolf and a poodle.

Second, human populations need to be sufficiently distinct–that is, isolated–for traits to be meaningfully different in different places. Of course, we can see that people look different in different places. This alone is enough to prove the point–people in Japan have been sufficiently isolated from people in Iceland that genetic changes affecting appearance haven’t spread from one population to the other.

What about the claim that “There’s more variation within races than between them”?

This is an interesting, non-intuitive claim. It is true–but it is also true for humans and chimps, dogs and wolves. That is, there is more variation within humans than between humans and chimps–a clue that this factoid may not be very meaningful.

Let’s let the authors explain:

Approximately 85 percent of human genetic variation is within-group rather than between groups, while 15 percent is between groups. … genetic variation is distributed in a similar way in dogs: 70 percent of genetic variation is within-breed, while 30 percent is between-breed. …

Information about the distribution of genetic variation tells you essentially nothing about the size or significance of trait differences. The actual differences we observe in height, weight, strength, speed, skin color, and so on are real: it is not possible to argue them away. …

It turns out that the correlations between these genetic differences matter. … consider malaria resistance in northern Europeans and central Africans. Someone from Nigeria may ave the sickle-cell mutation (a known defense against falciparum malaria,) while hardly anyone from northern Europe does, but even the majority of Nigerians who don’t carry the sickle cell are far more resistant to malaria than any Swede. They have malaria-defense versions of many genes. That is the typical pattern you get from natural selection–correlated changes in a population, change in the same general direction, all a response to the same selection pressure.

In other words: suppose a population splits and goes in two different directions. Population A encounters no malaria, and so develops no malria-resistant genes. Population B encounters malaria and quickly develops a hundred different mutations that all resist malaria. If some members of Population B have the at least some of the null variations found in Population A, then there’s very little variation between Pop A and B–all of Pop A’s variants are in fact found in Pop B. Meanwhile, there’s a great deal of variation within Pop B, which has developed 100 different ways to resist malaria. Yet the genetic differences between those populations is very important, especially if you’re in an area with malaria.

What if the differences between groups is just genetic drift?

Most or all of the alleles that are responsible for obvious differences in appearance between populations–such as the gene variants causing light skin color or blue eyes–have undergone strong selection. In these cases, a “big effect” on fitness means anything from a 2 or 3 percent increase on up. Judging from the rate at which new alleles have increased in frequency, this must be the case for genes that determine skin color (SLC24A5), eye color (HERC2), lactose tolerance (LCT), and dry earwax (ABCC11), of all things.

maps-europelighteyesIn fact, modern phenotypes are surprisingly young–blond hair, white skin, and blue eyes all evolved around a mere 10,000 years ago–maybe less. For these traits to have spread as far as they have, so quickly, they either confer some important evolutionary benefit or happen to occur in people who have some other evolutionarily useful trait, like lactose tolerance:

Lactose-tolerant Europeans carry a particular mutation that is only a few thousand years old, and so those Europeans also carry much of the original haplotype. In fact, the shared haplotype around that mutation is over 1 million bases long.

Recent studies have found hundreds of cases of long haplotypeles indicating recent selection: some have reached 100 percent frequency, more have intermediate frequencies, and most are regional. Many are very recent: The rate of origination peaks at around 5,500 years ago in the European and Chinese samples, and at about 8,500 years ago in the African sample.

(Note that the map of blue eyes and the map of lactose tolerance do not exactly correlate–the Baltic is a blue eyes hotspot, but not particularly a lactose hotspot–perhaps because hunter-gatherers hung on longer here by exploiting rich fishing spots.)

Could these explosions at a particular date be the genetic signatures of large conquering events? 5,5000 years ago is about right for the Indo-European expansion (perhaps some similar expansion happened in the East at the same time.) 8,000 years ago seems too early to have contributed to the Bantu Expansion–did someone else conquer west Africa around 8,500 years ago?

Let’s finish up:

Since we have sequenced the chimpanzee genome, we know the size of the genetic difference between chimps and humans. Since we also have decent estimates of the length of time since the two species split, we know the long-term rate of genetic change. The rate of change over the past few thousand years is far greater than this long-term rate over the past few million years, on the order of 100 times greater. …

The ultimate cause of this accelerated evolution was the set of genetic changes that led to an increased ability to innovate. …

Every major innovation led to new selective pressures, which led to more evolutionary change, and the most spectacular of those innovations was the development of agriculture.

Innovation itself has increased dramatically. The Stone Age lasted roughly 3.4 million years (you’ll probably note that this is longer than Homo sapiens has been around.) The most primitive stone tradition, the Oldowan, lasted for nearly 3 million of those 3.4; the next period, the Acheulean, lasted for about 1.5 million years. (There is some overlap in tool traditions.) By contrast, the age of metals–bronze, copper, iron, etc–has been going on for a measly 5,500 years, modern industrial society is only a couple of centuries old–at most.

What triggered this shift from 3 million years of shitty stone tools with nary an innovation in sight to a society that split the atom and put a man on the moon? And once culture was in place, what traits did it select–and what traits are we selecting for right now?

Is the singularity yet to come, or did we hit it 10,000 years ago–or before?

 

By the way, if you haven’t started the book yet, I encourage you to go ahead–you’ve plenty of time before next week to catch up.

Links Post

I have too many open tabs so let’s have a quick “what I’m reading” post

Millenials rediscover concepts like “dorms,” “boarding houses” and “apartments.” I’m not sure how this is novel.

Despite San Jose’s reputation for inclusivity (about 40 percent of residents are foreign born) and economic mobility (ranked best among U.S. cities), Mayor Sam Liccardo says the region’s affordable housing shortage has forced thousands to crash on couches, live in their cars, or stay on the streets.

Here, I think I see your problem:

Despite Because of San Jose’s reputation for inclusivity (about 40 percent of residents are foreign born) and economic mobility (ranked best among U.S. cities), Mayor Sam Liccardo says the region’s affordable housing shortage has forced thousands to crash on couches, live in their cars, or stay on the streets.

There. Fixed it for you.

On the other hand, these startups might be nice places to live.

Greater male variability, this time in response to solar cycles:

The authors use the vital statistics of 320,247 Maine citizens over a 29-year period to show that those born in 3-year peaks of 11-year solar cycles live an average of 1.5 years (CL 1.3–1.7) less than those born in non-peak years. Males are more sensitive than females to this phenomenon, which is statistically demonstrable well into adult life, showing the effect of probable UVR on the early human embryo despite superimposed adult lifetime hazards.

Genetic analysis of social-class mobility in five longitudinal studies:

… we studied social mobility in five cohorts from three countries. We found that people with more education-linked genetics were more successful compared with parents and siblings. We also found mothers’ education-linked genetics predicted their children’s attainment over and above the children’s own genetics, indicating an environmentally mediated genetic effect. Findings reject pure social-transmission explanations of education GWAS discoveries. Instead, genetics influences attainment directly through social mobility and indirectly through family environments.

Interesting Twitter thread on some recent antifa thing: 

White Woman: Your parents would be embarrassed by you–and your grandparents–who have been oppressed by white men throughout history. You should be ashamed of yourself.

Asian Man: Why?

White Woman: Because you’re an Asian giving in to white supremacy, motherfucker

I don’t know anything about Andy Ngo, the photographer who captured this segment and wrote the thread, but I do think there’s some seriously non-self-aware irony in a white person insulting and verbally abusing an Asian person for a perceived failure to feel oppressed by other white people. If she’s so concerned about whites oppressing Asians, maybe she should… stop doing it herself?

Portland is apparently turning into some kind of shithole:

As the crowd made their way to a nearby courthouse, they marched in the middle of the street, bringing traffic to a stop though they didn’t have a permit. Kent Houser, 74, made the mistake of attempting to pass them in his sedan. His car slowly pushed against a masked marcher. The crowd surrounded the car and started kicking it. After speeding down the block, Mr. Houser stepped out and was assaulted by the mob. They pushed him and smashed his car with clubs after he managed to get back inside the vehicle. No police were in sight even though the central precinct was blocks away. …

The mob later occupied a busy intersection. When a middle-aged man driving a car with North Carolina plates stopped in confusion, the agitators descended on him. “You white little f—er!” shouted one white man. “You are a little white supremacist. Go back to North Carolina where you came from.” The driver phoned police for assistance. Nobody came. …

A block away, police officers looked on passively. Why didn’t they respond? The department told me in a statement that it feared intervention would “change the demeanor of the crowd for the worse.”

Such lawlessness is increasingly typical here. Portland’s Resistance organized a protest after Election Day 2016 that turned into a riot. Masked vandals smashed stores and set fires, causing over $1 million in damage.

I remember those riots. They put a friend of mine who ticks every SJ-interest box you can name in danger, because antifa do not actually care about the people they claim to care about.

I’m sure the Portland Police would like to do their jobs, but it’s not worth it–either they’ve been told not to by their superiors or they’re guaranteed to get sued if they do.

 

 

Book Club Pick: The 10,000 Year Explosion

5172bf1dp2bnl-_sx323_bo1204203200_Our next Book Club pick is Cochran and Harpending’s The 10,000 Year Explosion: How Civilization Accelerated Human Evolution. From the book’s description on Amazon:

Scientists have long believed that the “great leap forward” that occurred some 40,000 to 50,000 years ago in Europe marked end of significant biological evolution in humans. In this stunningly original account of our evolutionary history, top scholars Gregory Cochran and Henry Harpending reject this conventional wisdom and reveal that the human species has undergone a storm of genetic change much more recently. Human evolution in fact accelerated after civilization arose, they contend, and these ongoing changes have played a pivotal role in human history. They argue that biology explains the expansion of the Indo-Europeans, the European conquest of the Americas, and European Jews’ rise to intellectual prominence. …

I just received the book, so I haven’t read it yet, but I’ve been a big fan of Greg and Henry’s blog (now Greg’s blog, since Henry passed away,) for a long time. I expect to finish reading and get the relevant discussion posts up, therefore, in about two months–I’ll update the time frame as we get closer.

Please let me know if you prefer short form discussion (like our discussion of Kurzweil’s How to Build a Mind,) or long form discussion (like Auerswald’s The Code Economy,) or something in between.