New research indicates modern man can be traced to one small group in Africa, according to professor Lynn Jorde of the Eccles Institute of Human Genetics at the University of Utah. Jorde told a genetics conference there is much more genetic diversity among Africans than Europeans or Asians, a finding that could overturn theories that man developed independently in several areas of the world.
“Once you’ve seen one European, you’ve pretty much seen them all,” Jorde told the International Society for Animal Genetics meeting Monday. The five day meeting runs through Wednesday. Jorde said the findings indicate Europe and Asia were colonized by Africans about 100,000 years ago. He said at one time the species was nearly extinct, numbering fewer than 10,000. Researchers from the Harvard School of Public Health and Louisiana State University studied 23 pairs of human chromosomes as well as cellular DNA passed on by mothers to their children, focusing on areas that contain strings of chemicals that do not express themselves as genes and are therefore overlooked by natural selection.
Jorde noted that aside from skin color, there’s very little variation among humans. By contrast, there is much more genetic variation among chimpanzees. “We are really a young species and there has not been much time for divergence to occur,” Jorde said in interviews after his lecture. Jorde predicted that now that the human genome has been mapped, the pace of genetic research will quicken.