ZURICH, SWITZERLAND—A genetic study conducted by paleogeneticist Verena Schūnemann of the University of Zurich and her colleagues suggests that modern humans contributed to the extinction of cave bears some 20,000 years ago, according to a report in The Washington Post. The scientists analyzed mitochondrial DNA, which is inherited through the female line, collected from 130 Ursus spelaeus individuals, and estimated the size of the female bear population over time. They determined that the bear population was stable between 200,000 and 50,000 years ago, before it began to crash about 40,000 years ago, when modern humans are thought to have arrived in Europe. Modern humans and Neanderthals probably hunted the bears for their skins and meat, but may have also been in competition with them for the shelter provided by caves. When combined with diminished food supplies brought on by climate change, Schūnemann said, the pressure of contact with humans may have driven the bears to extinction. To read about Neanderthal cave structures, go to "Early Man Cave," one of ARCHAEOLOGY's Top 10 Discoveries of 2016.