War and Terror – It’s Time to Stop the KillingSomewhere within the last 120,000 thousand years, our ancestors began migrations quite different from any that appear in the archeological record preceding that time and somewhere between forty and fifty thousand years ago those migrations accelerated to the point that Cro Magnon hominids, our forebears, settled every nook and cranny on the planet. The last major migration occurred when the land bridge opened up in Siberia, as the glacier receded ten thousand years ago, and Homo Sapiens, who our species had become by then, trudged all the way to Tierra del Fuego within a thousand years or so.
Jared Diamond (“The Third Chimpanzee” & “Guns, Germs, and Steel”) makes a case for some biological change, probably related to speech, as the variable making such migrations possible. He also makes the observation that these human migrations were coincident with the extinction of large mammals. The archeological evidence seems to bear this out. All over the planet there is fossil evidence of the extinction of one large mammal after another at approximately the same time the human migrations happened in that part of the world. Some scientists speculate that the cause of these extinctions ismore complicated than the fact that they are coincident with the expansion of the number of humans and they are probably right; but something of major proportions in the evolution of our species definitely changed to allow humans to sweep across all but the most uninhabitable places on earth in a relatively short period of time.
Dr. Diamond is careful to temper his speculation with the caution thatall the facts are not yet in, and probably never will be, I might add. As abiology-oriented scientist, he continues to look to some physical/anatomicalchange to account for the advances made by humans resulting in our capacityto take on the unknown dangers lying beyond the next range of mountains oracross the next river.
For a couple of million years humans had evolved fairly slowly towardthat point when a “great leap” occurred in the pace of our development.Anatomically we are about the same now as we have been for the last 125,000years, so the guess is that some language advancement made the difference.Linguists have traced the capacity to speak back through a few protolanguages to a point where the development of the ability to speak gets lost