OXFORD, ENGLAND—According to a Live Science report, Claudio Quilodrán of the University of Oxford and his colleagues analyzed more than 4,400 modern human genomes dating from 40,000 years ago to the present in an effort to determine why Europeans now carry less Neanderthal DNA than East Asians. When the researchers tracked the amount of Neanderthal DNA in the modern human genomes in relation to latitude, longitude, time, and region, they determined that the proportion of Neanderthal DNA in modern human genomes was indeed higher in Europe than in Asia until about 10,000 years ago. Up until that time, modern human hunter-gatherers who had migrated out of Africa mixed with Neanderthals in Europe. But then, some 10,000 years ago, Neolithic farmers migrated into Europe from the Middle East, where they had had little contact with Neanderthals. As the farmers and hunter-gatherers mixed, the amount of Neanderthal DNA in the European genomes was diluted, Quilodrán explained. Modern humans who migrated to East Asia some 60,000 to 70,000 years ago, however, did not mix with these Neolithic farmers from the Middle East. “What we propose is a simple explanation,” Quilodrán said. “It’s just migration.” Read the original scholarly article about this research in Science Advances. To read about the first successful sequencing of a complete Neanderthal genome in 2010, go to "Neanderthal Genome," one of ARCHAEOLOGY's Top 10 Discoveries of the Decade.