Friday, May 31, 2013

more clues that prove evolution

in the NYtimes: Mountain Populations Offer Clues to Human Evolution.
In 2010, Dr. Nielsen and his colleagues found variants of certain genes that were much more common in Tibetans than in the Han, the major ethnic group in China, who have lived for thousands of years at lower altitudes. By a wide margin, the winner was a gene called EPAS1. People with different variants turned out to have different levels of hemoglobin, suggesting that the gene was important to adapting to life at high altitudes. Recently, Dr. Nielsen and another group of colleagues published a study on people who live in the highlands of Ethiopia. They found no evidence that EPAS1 had evolved there as it did in Tibet. Instead, a different gene, BHLHE41, appeared to have experienced natural selection.