Matter: In the Bones of a Buried Child, Signs of a Massive Human Migration to the Americas

Genetic analysis of an 11,500-year-old skeleton discovered in Alaska suggests that North America was settled by a previously unknown people who originated in Siberia.

Native American Secrets Lie Buried in Huge Shell Mounds

Archaeologists in Maine are working to unearth artifacts buried for centuries in shell middens. But sea levels are rising, eroding the ancient sites.