Need for Speed?; June 2008; Scientific American Magazine; by David Biello; 2 Page(s)

Addis Ababa is the center of the genetic world. Not because of any special skill in genome analysis but because variation in the human genetic code diminishes as distance from the Ethiopian capital increases. After all, modern humans originated in East Africa.

Yet this genetic fact has led to some divergent conclusions. Some researchers have looked at the differing makeup of populations and argued that human evolution must be speeding up to explain all the variation. Others see that variation as yet more proof that a relatively small number of individuals migrated out of Africa and founded the current populations in other parts of the world.