A while ago I wrote about the Neanderthal theory of autism (NAT). For those of you who don’t remember (and are too lazy to click on that link), it’s the idea that autism spectrum disorder is a result of having additional Neanderthal genes. Everyone is about 4% Neanderthal and NAT proponents believe autistic individuals simply have a higher percentage; and that autism is not a condition but just a result of the fact that there were social differences between us and Neanderthals.
It’s an idea that should not be immediately dismissed for it has a bit of plausibility. However, plausibility only gets you so far and the evidence proponents give to make up the difference is wanting. All they do is try and find any similarity between Neanderthals and autistic individuals before claiming it as proof. For starters, this method is hopelessly unscientific. In science you make a prediction about how something should be if your hypothesis is correct and then check to see if it actually is that way. This (hopefully) avoids mistakes like cherry picking data and other nasty problems.
However, I think the biggest problem with the NAT evidence is that the similarities they claim as evidence are simply false. Descriptions of autistic traits come from informal internet surveys and descriptions of Neanderthal traits come from inside the author’s head. The result is that I wind up breaking into giggling fits whenever I try and read the NAT website.
My favourite piece of evidence is the claim that autistic individuals like walking on their tippy toes, which shows they are Neanderthal hybrids because Neanderthals were good hunters and had to sneak.
Despite this top quality evidence, many continue to advocate NAT. In fact, I’ve received a far few critical comments on my original article. That’s right, people have dared to criticise me! The nerve. These critics all made reference to genetics. The claim is that autism is less prevalent in Africa, where Neanderthal genes are less common. This correlation between Neanderthal genes and autism is one of the best pieces of evidence in favour of NAT.
Of course saying that it’s the best piece of evidence for NAT doesn’t say much when it’s crammed in with gems like “Neanderthals worked wood, therefore they could’ve made fences, therefore they were farmers, which explains why autistic individuals like animals.”
Except on closer examination, this top quality genetics data falls down. For starters the lower rates of autism documented in Africa come from very few studies. Whilst interesting, there simply isn’t enough data to make any claims about the prevalence of autism in Africa. Almost every psychologist with an interest in the field concedes that, as good as these few studies are, they simply aren’t comprehensive enough to identify the autism rate in Africa.
A work around to this problem would be to examine the autism rate amongst Africans living in Western countries where autism diagnosis techniques are more comprehensive and larger amounts of data is available. Unfortunatley for NAT proponents when these studies are performed they do not find a lower incidence of autism amongst Africans. In fact, many even document a higher rate than in the general population!
In short, the only decent piece of evidence in favour of NAT is non-existent. There is not the correlation between genetics and autism rates one would expect if the NAT is true, providing very strong evidence that it is actually untrue. Hopefully this means we can put the NAT behind us once and for all and start looking for the real cause of autism. Like aliens.
Also, I expect comprehensive apologies from all my critics for saving them from nonsense. If you can’t figure out just how to express your gratitude I also take monetary donations.