Scientists finally know why early human migrations out of Africa failed

New research reveals why early human attempts to leave Africa repeatedly failed—until one group succeeded spectacularly around 50,000 years ago. Scientists discovered that before this successful migration, humans began using a much broader range of environments across Africa, from dense forests to harsh deserts. This ecological flexibility, developed over thousands of years, gave them the adaptive edge needed to survive the more difficult exit routes into Eurasia.

source https://www.sciencedaily.com/releases/2025/06/250625111542.htm