Back to Africa: Ancient Human Genome Reveals Widespread Eurasian Mix

Genes from a 4,500-year-old skeleton from Ethiopia show how migrations shaped modern populations

A view from Mota Cave in Ethiopia, where archaeologists found the remains of a 4,500-year-old human. (Kathryn and John Arthur)

By Brian Handwerk

smithsonian.com

An ancient skeleton found face down in an Ethiopian cave has enabled scientists to sequence one of the first ancient African human genomes.

The sequenced genes are helping to define a wave of Eurasian migration back into Africa that now appears twice as large as previously believed—even if the reasons for the migration remain a mystery.

“This back migration of Western Eurasians to Africa was a very large, one-off event, it seems,” says study coauthor Marcos Gallego Llorente of the University of Cambridge. “Its genetic signature got to every corner of Africa.”

All humans trace their genetic roots back to Africa, but some modern Africans have a surprisingly large percentage of Eurasian ancestry due to the Eurasian backflow, a previously known migration from the Near East and Anatolia into the Horn of Africa. Read more.