The Last Glacial Period—which lasted from around 110,000 to 12,000 years ago—covered much of North Eurasia in ice and made it difficult for Neanderthals to survive. Estimates for their population size vary from 5,000 to 70,000—tiny when one considers that they were spread across a region that stretched from the Atlantic Ocean to Siberia.[71] It shouldn’t come as a surprise that there is evidence of long-term inbreeding.
