Thursday, April 20, 2006

Bayesian Estimation of the Timing and Severity of a Population Bottleneck from Ancient DNA   posted by Razib @ 4/20/2006 07:23:00 PM

Check out this cool paper in PLOS Genetics:

In this first application of the approximate Bayesian computation approach using the serial coalescent, we demonstrated the estimation of historical demographic parameters from ancient DNA. We estimated the timing and severity of a population bottleneck in an endemic subterranean rodent, Ctenomys sociabilis, over the last 10,000 y from two cave sites in northern Patagonia, Argentina....We found a decrease from a female effective population size of 95,231 to less than 300 females at 2,890 y before present: a 99.7% decline. Our study demonstrates the persistence of a species depauperate in genetic diversity for at least 2,000 y and has implications for modes of speciation in the incredibly diverse rodent genus Ctenomys. Our approach shows promise for determining demographic parameters for other species with ancient and historic samples and demonstrates the power of such an approach using ancient DNA.

I hope John Hawks and the gang can get their buddies to lend them some ancient DNA! The character of human evolutionary bottlenecks is a major issue in how we view the origin of our own species. There is other cool stuff about founder effect speciation (founder flush?) and the evolution of sociality via kin selection. Oh, and I don't know where the molecular clock variation across taxa debate is now, but I'm still a little surprised that after 2,000 years a rodent species couldn't "bounce back" a little more mutationally.