CAMBRIDGE, ENGLAND—Live Science reports that a previously unknown population of ancient humans was identified by sampling DNA extracted from 31,000-year-old children’s teeth unearthed in northeastern Siberia. The teeth were the only human remains discovered among the stone tools, ivory objects, and animal bones at the Yana Rhinoceros Horn Site, which is located on the Yana River. Martin Sikora of the University of Copenhagen said the children’s population group was distantly related to hunter-gatherers from western Eurasia, whose ancestors had separated from them some 40,000 years ago. No signs of inbreeding were detected in the children’s genomes. “This is despite the very remote location, suggesting they were organized in larger networks with other hunter-gatherer groups,” Sikora said. Later migrants to Siberia have been found to be related to peoples from eastern Asia. The differences between Siberian populations have also been noted in differences in material culture, he added. To read about a stunning medieval fortress in the middle of a Siberian lake, go to "Fortress of Solitude."