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?