By now some of you have heard of the family that walks on all fours. I got a tip on this story weeks ago from World Science, which has been tracking this for a while and has a new update from a researcher that says this is a "credible" empirical finding. I didn't really intend to post about this for the following reasons:
1) A high probability that it is a hoax. The British media was the first mainstream organ to really take off with this, and they aren't known for their scientific credibility (Nature, The Daily Telegraph is not). Additionally, the findings are coming out of the heart of Central Anatolia, and so are relatively hard to check for most Western scientists. Nevertheless, Carl Zimmer has many more details, including a comment from one of the scientists in question who have seen this family first hand, which suggests this is probably not a hoax to the first order.
2) The packaging of this as an "atavism" or "reverse evolution" is ridiculous. Evolution does not move along one highway, ascending the Great chain of Being (nor do I believe the canals are infinite, rather, there are a wide range of stable states I suspect). Bipedalism is probably not a trait that emerged fully formed from the head of Zeus. This family, if they are not the Tasaday of our day, are likely a pathology of some sort. One can get to the same phenotype (non-bipedalism) in a variety of ways. It seems that there are a host of deleterious correlated traits associated with this family (Carl mentions retardation), if this non-bipedalism was highly adaptive one assumes that over time modifier genes would crop up that would mask the deleterious side effects of the allele of large effect.
3) The appeal of this story, and its legs, suggest what people really find important. And, I think it shows why saltationism will always have staying power as a hypothesis, there is public demand for it!
- Log in to post comments
Connecting this to your blindness post: maybe blind people represent an ancestral state of homo sapiens, where people had intricately designed eyes & visual parts of their brain, but for whom these complex organs didn't function! Just as logically sound as the all-fours account, but the average chimpanzee or gorilla isn't blind, so the Great Chain of Being trap isn't as seductive as for all-fours.
The Weekly World News also has a lot of interesting science stuff. People laugh about the idea of a crocodile-human chimera, but a lot of women find crocs terribly attractive.
Some counter-evidence on the Tasaday. Since I have a (one-degree of separation) personal relationship with the author, through a person whom I respect intellectually, I tend to believe him. (I'm only human, you know, and I don't have the time or expertise to personally evaluate the evidence.)
I'm not on top of the Tasaday story, but I don't remember it quite being dismissed as a hoax. What I remember is the accusation that the discoverers had oversold their discovery, dressed up in a lot of cheesy speculation and media-savvy pop anthro.
Assuming this isn't a hoax (which is certainly possible), it looks like another case of Middle Eastern cousin marriage in action. From the Times of London:
"Their mother and father, who are themselves closely related, are believed to have passed down a unique combination of genes resulting in the behaviour."
A quick check of the invaluable www.Consang.net finds that the three studies of Kurdish populations all show that about 3/8ths of their marriages are between first or second cousins.
I was wondering whether you knew who are behind World Science. I mean, hell... who are they?
i think it is one dude. i've been on his mailing list for a while, he hit me up for a link about 6 months ago. i told him to change the "look & feel," it was too 1997....
I actually have a link on the site out there as well. See the BBC banner, that's me.
But don't really know what his background is actually.