A study of a handful of 300,000-year-old teeth revealed an ancient human group had a mix of archaic and modern tooth features.

A small collection of 21 teeth may have big implications for the evolution of humans in Asia. The dentition, which comes from a mystery human ancestor that lived at least 300,000 years ago in China, shows an unusual combination of features that may suggest early humans interbred with Homo erectus, a new study reveals.

The Hualongdong discovery reminds us that human evolution was neither linear nor uniform, and that Asia hosted multiple evolutionary experiments with unique anatomical outcomes.