African Ancestors, Races, And The Toba Supervolcano

TOBA SUPERVOLCANO, A TIME WE CHANGED By Tom Slattery Yes, we're all Africans. That has been firmly established. We humans come from a mutation that occurred in Africa over 200,000 years ago. Most of us who are not of African ancestry have been shown to have had ancestors who came out of Africa in two waves, one roughly 100,000 years ago, the other roughly 50,000 years ago. My hypothesis, call it my guess, is that we have our present slight physical appearance variations that we erroneously call "race" as a result of the massive explosion of the super-volcano Toba on Sumatra roughly 75,000 years ago, midway between these two waves. The Toba super-eruption created a sulfur and dust cloud that blocked sunlight, possibly years. Vegetation could hardly grow if it could grow at all. The result of that was a massive loss of animal life, including human life. Human population dwindled to only a few thousand surviving individuals. The first wave out of Africa began around 100,000 years ago and took place before Toba exploded. Among others, these first-wave ancestors have been shown to have been the ancestors the present Australian aborigines. And let me offer a bit of interesting if wild conjecture. By the fact that these ancestors of Australian aborigines were able to cross considerable water from the Asian landmass and eventually arrive and settle in Australia, one might infer that they had developed adequate nautical competence. They also seem to have crossed the Red Sea from Africa into the southern Arabian peninsula to begin their consequential journey. Use of primitive boats offers a reasonable explanation. Large dugout canoes made from rain-forest logs using stone tools and burn-out techniques would not seem impossible for them to have manufactured. Primitive outrigger setups may even have been devised. Rudimentary navigation using sun and stars and an easing of the workload by using primitive sails would not seem impossible for them to have used.

Some may have tired to go north into Europe and central Asia, but there would have been a big problem. The physically larger and stronger Neanderthals were still prominent and powerful across the western and southern Eurasian continent. These first wave ancestors would have been poor match for them in terms of combat or numbers. So whether traveling by sea or by land, this first wave of migration out of Africa appears to have hugged the coast of south Asia, eventually reaching Australia. It is not impossible to visualize small fragile settlements growing up over hundreds of thousands of years along the migration route. Most or even all of these would probably have been obliterated by a giant tsunami resulting from the Toba explosion's mega-earthquake. After reaching central or eastern Asia these humans of the first wave probably migrated north around the Neanderthals and into east Asia. The competition there may have been Homo erectus. Like the Neanderthals, Homo erectus would probably not have been unsimilar-looking nor unsimilar self-aware beings and resentful of the new intruders. But there is a lot of land in Asia. Whether welcome or not, some of the firstwave people seem to have established themselves there. The first wave may have gone on, growing in population and proficiency, for perhaps 20,000 to 25,000 years. Just consider what we present civilized humans were only 5000 years ago at the beginning of civilization in the Middle East. 20,000 years is a lot of time to create fixed or hunter-gatherer communities and increase population. Then the Toba super-volcano exploded. And apparently very few of these first-wave humans or their stay-behind relatives in Africa survived. Both mitochrondrial and Y-chromosome (female and male) DNA tracing may indicate that a far smaller number survived. In an article in the July 2007 Vanity Fair, former Stanford postdoctoral fellow and Oxford research fellow Spencer Wells, now head of the Genographic Project, says DNA studies suggest that human population may have dwindled to as few 2,000 individuals. Inbreeding in extremely small and very isolated surviving clans might explain our present so-called "race" appearances.

And they survived isolated for millennia -- some in Australia, some in China, and some in Africa, where the second wave had already begun to migrate. But over tens of millennia population grew. When population had rebounded, a second wave migrated north, into where the physically powerful Neanderthals once had lived in great numbers. They must have been decimated by the Toba explosion, too, although one might speculate less so due to their ability to survive in colder climates. The second wave began heading up into Europe roughly 50,000 years ago, maybe 25,000 years after the Toba super-explosion and a long enough time to allow human population to grow to previous levels or more. Whether they genetically mixed with the Neanderthals or learned from them is an open debate. But the second-wave lived among or in proximity with them for as much as tens of thousands of years. It would seem, then, that from three remnant isolated clans of survivors of the Toba catastrophe, maybe numbering as few as 2000 individuals in total for all three, we grew into our present overpopulation of six-and-a-half billion individuals with three distinct so-called "racial" appearances. There may have been an isolated clan of a few individuals in east Asia, the present so-called "Mongoloid race". There may have been an isolated clan in Australia, the present Australian aborigines who are close to African blacks. And there may have been a small clan of individuals isolated in central or western Asia or Europe. And some of these may have mixed with the second wave out Africa that had grown from a few surviving individuals there. And the second wave into Europe may or may not have also mixed with the Neanderthals. There is a debate about red hair color being derived from mixing with Neanderthals, for instance. So that is my wild hypothesis, my guesses about how the present so-called "racial" divisions could have happened. END