All,
The impact that Mount Toba eruption may have had on human evolution, about 70,000 years ago, has already been brought up,
HERE and
HERE. The following (obtained from M. Brass' Palaeoanthropology list) is an interesting rebuttal of the conclusions presented in the earlier papers by Ambrose and others. Below, the conclusions of this short (News and Views) paper.
Jacques Cinq-Mars
Gathorne-Hardy, F.J. and W.E.H. Harcourt-Smith. 2003. The super-eruption of Toba, did it cause a human bottleneck? Journal of Human Evolution 00:1–4.
In summary, we have not been able to find any evidence to support the hypothesis that the Toba super-eruption of 73.5 Ka caused a bottleneck in the human population. The direct effects of the eruption were fairly localised, and at the time probably had a negligible effect on any human population in Asia, let alone Africa. Genetic evidence indicates that the Pleistocene human population bottleneck was not hour-glass shaped, but rather an up-side down bottle with a long neck. Modern humans at that time were adaptable, mobile, and technologically well-equipped, and it is likely that they could have dealt with the short-term environmental effects of the Toba event. Finally, we have found no evidence for associated animal decline or extinction, even in environmentally-sensitive species. We conclude that it is unlikely that the Toba super-eruption caused a human, animal or plant population bottleneck.
Copyright © 2003 Elsevier Ltd. All rights reserved.
