New Horizons in Science

We usually think of evolution occurring over millions of years. But modern humans changed their environment 10,000 years ago with the development of agriculture and the decline of nomadic life. And they’ve been evolving very rapidly ever since. Genes for lighter skin, for example, are new and increasing in Europeans and Asians. Genes related to hearing are evolving very rapidly as well, possibly demonstrating that humans are adapting to language—or to the different sounds needed in particular languages. Genes that increase a population’s fitness could lead to greater population growth, spread, and clashes with neighbors—as when populations north of Italy swept into territory once part of the Roman Empire. John Hawks is also comparing modern human DNA to the Neandertal genome, just now becoming available for study, to find out which mutations distinguish us from these very close relatives.

References

Hawks J, Wang ET, Cochran G, Harpending HC, Moyzis RK. 2007. Recent acceleration of human adaptive evolution. Proc Nat Acad Sci USA 104:20753-8. doi: 10.1073/pnas.0707650104 (see link below)

Hawks J, Cochran G, Harpending HC, Lahn BL. 2008. A genetic legacy from archaic Homo. Trends Genet 24:19-23. doi:10.1016/j.tig.2007.10.003