Sticking to science, the generally quoted figure for that megavolcano Toba is about 74,000 years ago, not 85 thousand. What gets me is the lack of significant communication between different science disciplines. This post vaguely suggests a genetic bottleneck perhaps cause by climate change and a volcano. This is already pretty well established science. Toba is a caldera 18 by 65 miles in size. Pinatubo left a caldera 1 1/2 to 3 miles in diameter. Most of us remember the 500 year floods of the Mississippi, and other severa weather for several years after.
I have several questions. How big was the population immediately before Toba? Could the Toba bottleneck have affected the genetics of this study so that their figure for the humanoid population a million years ago might be seriously underestimated? There is no doubt that there was a significant downward movement of temperature in the millenia after Toba, and from everything I read in archaeology/anthropology, it was not until about 50 thousand years ago that enough population had regenerated to start leaving significant traces/finds.
Also from about 30 to 20 thousand years ago, there were several additional sharp drops in temperature, until the climate began to warm about 18,000 years ago. I have identified one drop at 22,000 ya when Sakura-Jima volcano blew leaving a 15 mile diameter caldera. Anyone have candidates for at least two other significant drops between 20 and 30 thousand years ago?
I’m not sure if anyone has ever been able to do a proper estimate, but it is easy for me to think that the world-wide population could have been much larger than most people might imagine.
Moreover, the “bottleneck” population estimates are made on the basis of a genomic analysis and hence only estimates the size of the population that contributed to the majority modern human genome.
There is, I think good reason to believe that some fairly significant populations of pre-Toba humans could have survived to the east of the Toba caldera, in Java, the lesser Sunda Islands, and what is now New Guinea, as well as in some parts of penninsular Malaysia.
These stocks may be the ancestors of the negroid peoples of New Guinea and the Andaman Islands. These groups have not made any significant contribution to the wider gene pool, and would have been immaterial to the bottleneck. They may have survived in much larger numbers than the majority ancestors, only to dwindle later under pressure from modern humans in the last 15-20 thousand years.
Perhaps some hominid variants such as the “hobbit” people of Sumba who apparently co-existed with pygmie elephants right up to the arrival of modern humans a few thousand years ago were survivors of the Toba event.