We talk about molecular population and evolutionary GENETICS and GENOMICS. You know, the caliper measurement of a gene's evolvability in moles.For those of you interested in recent adaptive evolution in some insignificant bipedal primate, John Hawks and pals have published a paper in PNAS describing something you'll find interesting. Of course, if you're interested in such things, you already know that. Here are some links related to Hawks et al. paper:
- The Hawks et al. paper presents data to suggest a recent burst in adaptive evolution along the human lineage. The reason for this burst is an increase in populations size, allowing for more beneficial mutations in the species. Eventually, the paper itself will be available here. Until then, you can find it here.
- This post from p-ter at GNXP takes a critical look at the methodology employed by Hawks et al. P-ter argues that the methodology is biased toward detecting recent events. Hawks replies to p-ter here.
- John Hawks has a couple of other posts about the paper and the coverage surrounding it. He announces the paper here, describes the press coverage here, summarizes the results here, and links to a bunch of people here.
- Razib has posted come stuff on this, too (he's interested in these boring topics). He has described the theory and results and covered some of the stuff other people have written.
- Various other bio-bloggers have put in their 2cents. The new blog Popgen ramblings suggests that Hawks et al. did not perform the appropriate simulations to test for false positives. Some other non-specialists have also weighed in. These include T. Ryan Gregory's complaints about the way the authors are describing the research in the press, Larry Moran's skepticism, and Greg Laden's admiration.
If I read the paper, I may offer my own opinions. Maybe. And that's if I read the paper any time soon. But I figured I'd post something on it because it's getting so much hype. I thought Hawks didn't like hype.
Life Science
Comments
Thanks for the plug, though I am confused as to how Larry and I are considered "non-specialists" when our comments related to basic evolutionary points.
Posted by: TR Gregory | December 14, 2007 8:58 AM
I was worried that would be misinterpreted. Specialists = population geneticist. I only linked to life scientists, but the specialists have focused training in population genetics (especially human popgen).
Posted by: RPM | December 14, 2007 9:40 AM
Fair enough. However, the implications -- and the statements from the authors -- go well beyond the limited sphere of pop gen and cross into the expertise of others, including evolutionary biologists generally (me) and anthropologists (Greg Laden). Anyway, it's a minor point. Indeed, I am waiting for specialists (in the narrower human pop gen sense) to provide peer-reviewed responses to this one as I expect it will prove controversial.
Posted by: TR Gregory | December 14, 2007 9:58 AM
Indeed, I am waiting for specialists (in the narrower human pop gen sense) to provide peer-reviewed responses to this one as I expect it will prove controversial.
As am I.
Posted by: RPM | December 14, 2007 10:07 AM
Thanks for the comment and the links!
I'm worried that most people seem to think the most controversial thing we have done is to read R. A. Fisher! For some reason, theory is out of style in genetics today.
I've been reminded many times of the old joke, "What do you call a population geneticist?"
"Emeritus."
Posted by: John Hawks | December 14, 2007 10:28 AM
John, it doesn't seem like people are taking issue with the theory that predicts a recent burst in adaptive evolution. But rather they have problems with the data analysis you guys performed. The debate seems to be over power and false positives/negatives.
Posted by: RPM | December 14, 2007 10:45 AM
My problem isn't with the theory in the least -- it makes good sense. My problem isn't with the data, as the paper still isn't available (though I see a pre-print is floating around). My problem, so far, is entirely with the hype the press are reporting, most of it direct quotations.
Posted by: TR Gregory | December 14, 2007 11:04 AM
Hi, RPM -- I agree, the best comments we've gotten from specialist blogs relate to ascertainment and false positives/negatives. I expect that when you read the paper, you'll probably be thinking along those lines too.
There are only about three asking these methodological questions about the analysis, though. Most seem to be reacting viscerally to the idea that evolution could "accelerate" by as much as we claim. That's a deficiency of theory and/or knowledge about human history, which we're trying as hard as we can to make a dent in.
Posted by: John Hawks | December 14, 2007 11:20 AM
My admiration is very limited in this case. I was being polite. I think the paper may be OK, but flawed. But the post-paper extra-peer-review rantings, especially of Henry's, are absurd. They are making royal fools of themselves.
To tell you the truth, I'm too spitting mad to write about it, or I'd kick their asses. Eventually, I will.
Posted by: Greg Laden | December 14, 2007 1:31 PM
Greg, I'm not clear what you're talking about.
Posted by: RPM | December 14, 2007 2:32 PM
The Economist:
http://tinyurl.com/2aknqs
"The finding that may cause most controversy, however, is that in the Asian groups there has been strong selection for one variant of a gene that, in a different form, is responsible for Gaucher's disease. A few years ago two of the paper's other authors, Gregory Cochran and Henry Harpending, suggested that the Gaucher's form of the gene might be connected with the higher than average intelligence notable among Ashkenazi Jews. The unstated inference is that something similar might be true in Asians, too.
... The paper Dr Moyzis and his colleagues have just published is a ranging shot, but the amount of recent human evolution it has exposed is surprising. Others will no doubt follow, and the genetic meaning of the term "race", if it has one, will be exposed for all to see."
The Times
http://tinyurl.com/2vgjqf
"For much of the past 10,000 years, most human populations have been highly separated from one another. It is thus to be expected that they will have evolved in slightly different ways in response to their regional environments. While 99.9 per cent of human DNA is shared by all, the bits that vary sometimes tend to differ between races.
...(I)t can be misinterpreted to serve a racist agenda, and the authors' comments have not helped to ensure against this. Harpending's dubious Viking proposition implies that certain ethnic groups are genetically more violent than others, an unsubstantiated idea that could feed prejudice.
[Harpending's] contention that the trend towards greater difference is recent and continuing is also apt to mislead. ... Greater movement and cultural transfer between continents will probably make humans more similar to one another, not more different."
Posted by: Colugo | December 16, 2007 11:22 AM