By Anthea Lacchia
New research suggests that volcanic eruptions drove Neanderthals to extinction, allowing modern humans to establish themselves in Northern Eurasia. This theory is reported in the October issue of Current Anthropology.
Researchers have linked the massive eruptions that took place around 40,000 years ago to ash layers found in the Caucasus Mountains of southern Russia, where Neanderthal bones and tools have been found.
The ash cloud that was funnelled into the atmosphere following the eruptions would have led to global winter conditions and severe damage to many ecosystems. Carbon dioxide levels would have also undergone a sharp increase. Millions of years before this, eruptions of a similar scale are thought to have contributed to the demise of the dinosaurs.
However, it is likely that the eruptions in the Caucasus region did not have a direct impact on early modern humans, who occupied more southern parts of western Eurasia and Africa.
The research team concluded that modern humans benefited from the newly opened niches of northern Eurasia, allowing them to colonise these new areas unimpeded by competition with Neanderthals.