early human migration

Native Americans may have arrived in the Americas via several routes

Early excavation site in Beringia with mountains in the background
Excavation of early site in the Beringia area of Alaska. Photo: Ben Potter/University of Alaska Fairbanks

In the long debate over how and when the first Native Americans arrived in the Americas, a group of scientists is arguing that multiple viable possibilities exist, according to a new study in Science Advances Wednesday.

Why it matters: Although there are many circulating theories, research over the past 20 years leans toward the idea that Native Americans arrived via a coastal route around 20,000 years ago. But, this team says they've reviewed enough evidence to indicate another theory is equally or even more strongly true — that they arrived via an inland route. Plus, they say, the earliest they arrived was closer to 16,000 years ago.

Humans left Africa far earlier than we thought

Data: Sites compiled from various science journals; Map: Andrew Witherspoon/Axios

The stories of our distant ancestors — when and how they evolved into the Homo sapiens we are now, and how they migrated and eventually populated the world, often center on an exodus of modern early humans from Africa about 60,000 years ago.

What's new: A growing number of researchers believe while there may have been a main migratory event then, recent findings and new technology reveal that groups likely traveled out of Africa and its bordering Levant region earlier than previously thought. The map above by Axios' Andrew Witherspoon shows some of these recent findings.