LONDON, ENGLAND—According to a Science News report, Neanderthals and modern humans split from a common ancestor more than 800,000 years ago, or significantly earlier than previously thought. Paleoanthropologist Aida Gómez-Robles of University College London calculated the rate of changes in tooth shape for eight ancient hominid species, and then examined 430,000-year-old Neanderthal teeth recovered from Sima de los Huesos, a site in Spain. Based upon the steady rate of change of tooth crowns in the other hominid species, she determined that the distinctive shape of the Neanderthal teeth began forming between 800,000 and 1.2 million years ago. Analysis of Neanderthal DNA has suggested the last common ancestor of the two species lived between 550,000 and 765,000 years ago, but researchers do not agree on the speed of genetic mutations, or how consistent that change may have been over time. For more, go to “A Traditional Neanderthal Home.”