Generally, sub-Saharan Africans have low scores on IQ tests, educational assessment tests like PISA, etc.
Does that mean that all Africans are the same? No. Could some population in Africa do considerably better, say more like Europeans or East Asians?
Sure: there’s no law of physics that would make it impossible. If local selection pushed in that direction, it could happen.
Has it happened? Maybe on a sub-national,tribal scale. Not on a national scale: every country in sub-Saharan Africa does poorly.
Occasionally I hear people talk about Africa’s great genetic variety. It exists: the genetic difference between Bushmen and Bantu is bigger than the difference between Bantu and Finns. A couple of thousand years ago, before the Bantu had arrived in South Africa & mixed with the Bushmen, it was even bigger: looking at ancient DNA from those unmixed Bushmen, looks as if they split off from the rest of the human race at least a quarter of a million years ago. Well before anything that looks like behavioral modernity, by any definition. Half as divergent as Neanderthals.
But the most divergent populations are small. There are fewer than 100,000 Bushmen, on the order of a million Pygmies, around 1000 Hadza. Most people in Africa are Bantu or related populations: next after that are Nilotic peoples.
I like simulations: I’ve written lots of them. I’ve used them to understand questions better – questions like the electronic structure of semiconductors, the evolution of Ashkenazi intelligence, and methods of combining adaptive optics and imaging processing.
There are systems that are hard to simulate: stuff that’s highly nonlinear, or where the some of the key factors are poorly understood and/or poorly measured, when the required calculations grow exponentially, etc.
There are also systems that can be simulated essentially perfectly. The relevant physical laws are known exactly, as are the system parameters – while the required computations scale nicely.
This is the case for optics: there are codes that can accurately predict the performance of conventional optical systems. I used to work in an optical design shop [EDSG, part of Hughes Aircraft] where they did this every day.
Once they had designed and built a prototype of a periscope-type system (for an AFV, if memory serves). A general arrived for the big demo and looked at a target through the prototype.
“It’s upside down.”, he said. and so it was. That’s why they pay these guys the big bucks.
The prototype had only been tested on a crosshair reticle: looked the same upside down as right side up. Fixed with a prism.
To err is human, true in writing sims as well as everywhere else in life: but tests can expose those errors.
I’m thinking of reviewing some books that are not hilariously stupid: I can’t promise that my review will make you laugh. I’m looking for some money for book-buying – probably ebooks, because that’s faster and doesn’t threaten to collapse my house. Paypal or bitcoin works, but I’ve been hankering for a few Maria Theresa thalers.
It now looks as if the majority of the genetic variance in IQ is the product of mutational load, and the same may be true for many psychological traits. To the extent this is the case, a lot of human psychological variation must be non-adaptive. Maybe some personality variation fulfills an evolutionary function, but a lot does not. Being a dumb asshole may be a bug, rather than a feature. More generally, this kind of analysis could show us whether particular low-fitness syndromes, like autism, were ever strategies – I suspect not.
It’s bad new news for medicine and psychiatry, though. It would suggest that what we call a given type of mental illness, like schizophrenia, is really a grab-bag of many different syndromes. The ultimate causes are extremely varied: at best, there may be shared intermediate causal factors. Not good news for drug development: individualized medicine is a threat, not a promise.
On the other hand, this bodes well for our secret project aimed at ‘accidentally’ creating a super-Neanderthal.
Often you can come up with better explanation by taking a wider view. For example, I’ve heard people suggest that Europeans have lower IQs than Ashkenazi Jews because of priestly celibacy.
But a broader perspective suggests that is not key: lots of populations that never had anything like priestly celibacy score lower and accomplish less than Western Europeans. Western Europeans aren’t anomalously dumb – Ashkenazi Jews are anomalously smart. Look for an explanation based on their genetics and history, not someone else’s .
In the same way, when looking at the wave of extinctions in North America about 12,000 years ago, the story becomes clearer if you consider the extinctions in South America ( a bit later), in the Caribbean islands ( thousands of years later), in Australia ( about 46,000 years ago) , on Madagascar and New Zealand, on various oceanic islands ( flightless birds disappear in Oceania and the Azores): the common factor is the arrival of modern humans.
Similarly, when considering the origin of cognitive differences between racial groups in the US, a wider perspective is helpful. Probably low scores in Zimbabwe are not caused by structural racism or implicit bias. You might want to blame Mugabe – but scores are similarly low throughout sub-Saharan Africa.
Testosterone Rex is a really stupid book. Interesting that none of the Establishment reviewers noticed. Anyhow, I was talking with a friend, and he opined that this is always the case – all the books by self-professed feminists are stupid. Since the world doesn’t work the way they’d like it to, this might seem inevitable, but on other questions I have to say that at least some of the people pushing false theories do a technically better job, are more proficient obscurers of the truth. For example, when Lewontin said that most genetic variation in humans is within-group [true] and therefore Pygmies can’t really be short [but they are short], he was pushing something untrue, but he didn’t sound nearly as dumb as Cordelia Fine when she claims that a guy getting tons of nookie won’t end up with extra kids.
If there are counterexamples, tell me.
Scott Alexander talks about our paper, Natural History of Ashkenazi Intelligence. He thinks it a good explanation of a burst of contributions by Ashkenazi Jews in the exact sciences in the early 20th century. His guys then comment extensively, if not always particularly wisely.