Neanderthals from Western Europe almost became extinct before modern humans set in

A new study of mitochondrial DNA sequences suggests that Western Europe may have undergone a population crisis during a cold stretch of the Neanderthal era.

Study co-author Love Dalen, associate professor at the Swedish Museum of Natural History in Stockholm, told Phys.org that the fact that Neanderthals in Western Europe were nearly extinct, but then recovered long before they came into contact with modern humans came as a complete surprise.

"This indicates that the Neanderthals may have been more sensitive to the dramatic climate changes that took place in the last Ice Age than was previously thought," Dalen said.

By analyzing the amount of genetic variation in the DNA from 13 Neanderthals, the scientists pieced together the puzzle of a demographic history. The DNA of Neanderthals from more than 50,000 years ago showed a high degree of genetic variation, in contrast to the DNA of those from less than 50,000 years ago. That group showed much less genetic variation.

Until now, the Neanderthal population was assumed to be stable until modern humans began showing up. Extinction was avoided when Neanderthals from surrounding areas repopulated the region.

But the new research suggests that Neanderthals may have been more susceptible to cold than previously thought.