|No comment . . .|
About 40,000 years ago in what is now Italy and the Caucasus Mountains straddling Europe and Asia, several volcanoes erupted in quick succession. The researchers argue that these eruptions caused a "volcanic winter" as ash clouds filled the sky, blocking the sun's rays, and that this may have lasted for years. The climatic shift devastated the region's ecosystems.
Evidence for the affect this volcanic winter may have had on neanderthal populations comes from Mezmaiskaya cave in the Caucasus Mountains of southern Russia. The site is rich in Neanderthal bones and artifacts, and recent excavations there have revealed two distinct layers of volcanic ash that coincide those volcanic events.
Analyzing the ash layers led to the discovery that there was a correlation between the thickness of a layer and the amount of pollen it contained; the thicker the layer, the less pollen it had. That's would be a good indicator that there had indeed been a dramatic shift in climate at the site at the time of the eruption and that plant populations had dwindled. The loss of plant forage would have led to a decline in plant-eating animals, and the neanderthals, who depended on large mammals for food, would have been affected. With that in mind, it is noticeable that the Neanderthal's presence at Mezmaiskaya appears to have come to an end following the second eruption as no bones or other neanderthal have been found above the second ash layer.
The idea for environmental factors playing a role in the extinction of the neanderthal is not new, but the research does provide new evidence and a mechanism to explain the cause of an environmental pressure the neanderthal would have experienced. It is not yet perfect as a hypothesis, and the researchers stress the need for further data in other parts of Europe, but their finds at Mezamaiska have provided the important supporting evidences needed for further research.
Than, Ker. September 22, 2010. Volcanoes Killed Off Neanderthals, Study Suggests.
University of Chicago Press Journals. 8 October 2010. Volcanoes Wiped out Neanderthals, New Study Suggests.