Out of Africa Again... and Again?; April 1997; Scientific American Magazine; by Tattersall; 8 Page(s)

It all used to seem so simple. The human lineage evolved in Africa. Only at a relatively late date did early humans finally migrate from the continent of their birth, in the guise of the long-known species Homo erectus, whose first representatives had arrived in eastern Asia by around one million years ago. All later kinds of humans were the descendants of this species, and almost everyone agreed that all should be classified in our own species, H. sapiens. To acknowledge that some of these descendants were strikingly different from ourselves, they were referred to as "archaic H. sapiens," but members of our own species they were nonetheless considered to be.

Such beguiling simplicity was, alas, too good to last, and over the past few years it has become evident that the later stages of human evolution have been a great deal more eventful than conventional wisdom for so long had it. This is true for the earlier stages, too, although there is still no reason to believe that humankind¿s birthplace was elsewhere than in Africa. Indeed, for well over the first half of the documented existence of the hominid family (which includes all upright-walking primates), there is no record at all outside that continent. But recent evidence does seem to indicate that it was not necessarily H. erectus who migrated from Africa--and that these peregrinations began earlier than we had thought.