Journey of Man

I was watching an interesting show on PBS the other day with the above title. By tracking genetic markers on the Y-chromosome a researcher was able to build a plausible narrative for when the various human migrations populated the planet.

Long ago in Africa there was a revolution in the human population. While all humans were hunter/gatherers, a new type of hunter emerged. It's difficult to determine whether it was a new way of thinking or a new way of communicating was the key element since language and thought patterns are so closely entwined. Whichever the case, this new hunter had advanced deductive skills and used those to become a tracker as well. By exercising his deductive powers, this new hunter could read animal tracks and traces and successfully hunt down prey that he had not even seen. Those same deductive powers brought about an advance in hunting technology that allowed him to set aside the heavy, high-maintenance stone weapons in favor of more portable and longer-range bone-tipped weapons. These techniques and this technology has been preserved by the Bushmen of South Africa. As it turns out , the purist, unmutated form of the Y-chromosome markers is also found in the Bushmen. They are the direct descendants of that ancient African race that gave rise to every human population on Earth. They are unique in that theirs is the only language that incorporates clicking sounds.

The researcher theorizes that at some point humans divided. One group kept the clicking language and another group that was going to eventually spawn the global migration lost the clicking sounds. That is why the !Kung language is so absolutely unique. Every other language comes from a completely different branch of the tree.

Between 45,000 and 50,000 years ago the world went into a glaciation cycle that brought severe drought to previously lush areas of Africa. This event forced humans (who were indigenious only to Africa at the time) to migrate to new territories. A portion of the non-clicking group headed up the East African coast to the Arabian peninsula and beyond.

Interestingly enough the next place the early African marker shows up is in the Aborigines of Australia. All traces of the migration that brought the Africans to Australia 45,000 years ago are gone or buried under the Indian Ocean. At the time of the migration the sea level was much lower than it in now. The Africans appear to have preferred a coastal environment so whatever they left behind is now miles out to sea. It seems that later migrations overran the older coastal peoples of Arabia and India. Only the relative isolation of Australia after the glaciation recedes and the sea levels rise prevents those migrations from washing over the Abos also. However the ancient markers found in the Abos can also be found among the Tamils of Southern India and Sri Lanka indicating that the early African diaspora passed through there.

Again at around 40,000 years ago there is another push out of Africa. By this time the people carry some distinctively different genetic markers than their predecessors. And this time they are inland dwellers rather than coastal dwellers. This new migration ends up in Central Asia. From the point they spread out in all directions. To China, to India, to Indochina. When the glaciers recede in Europe, it is populated from the pool of people in central Asia. The racial label of Caucasian is actually quite accurate. And eventually the Central Asians make their way to the Americas.