Laura Geggel // How 250 Siberians Became the First Native Americans

12.5.18

How 250 Siberians Became the First Native Americans: // livescience.com // These people, known as a founding group because they "founded" the first population, migrated from Siberia to the Americas by about 15,000 years ago, said study co-lead researcher Nelson Fagundes, a professor in the Department of Genetics at Federal University of Rio Grande do Sul, in Brazil.

Figuring out the size of founding groups is key, because it determines the amount of genetic diversity that gets passed on to the group's descendants, Fagundes said. [In Photos: Human Skeleton Sheds Light on First Americans]

That, in turn, could alter how effectively natural selection weeds out bad genes, Fagundes said.

"Large populations have very efficient selection, while in small populations, mildly deleterious alleles [versions of genes] can spread, which may increase genetic susceptibility to some diseases," Fagundes told Live Science in an email.