Ancestral Quandry; January 1998; Scientific American Magazine; by Wong; 2 Page(s)
After researchers published the first analysis of ancient human DNA in the journal Cell last July, the case was closed, or so it seemed. "NEANDERTHALS WERE NOT OUR ANCESTORS" read the cover, featuring a photograph of the archetypal specimen¿s skullcap with its heavy, arched browridge so unlike our own relatively smooth brows. The pattern of differences between Neanderthal and modern DNA indicated to the team that Neanderthals were an evolutionary dead end, replaced by modern humans without any interbreeding. Popular accounts hailed the research as proof of a recent African origin for all modern humans, but has the long-standing debate over human origins really been put to rest? Judging from subsequent reactions among geneticists and paleoanthropologists, apparently not.
The Cell paper supports the so-called out-of-Africa model of human evolution put forth by paleoanthropologist Christopher B. Stringer of London¿s Natural History Museum. It states that modern humans originated in Africa 130,000 to 200,000 years ago and spread from there less than 100,000 years ago, replacing archaic populations such as Neanderthals all over the world. The competing hypothesis is multiregional evolution, championed by University of Michigan paleoanthropologist Milford H. Wolpoff. It holds that humans arose in Africa some two million years ago and evolved as a single, widespread species, with multiple populations interconnected by genetic and cultural exchanges.