Fossils of the ancient human ancestor Homo erectus have been found in two locations in East Asia — near Beijing and in central Java, Indonesia — but whether this indicates one or more hominin migrations from Africa remains unclear. Now Yahdi Zaim at the Institute of Technology Bandung in Java and his colleagues report a 1.5-million-year-old H. erectus jaw fragment (pictured) that supports the occurrence of two waves of eastward migration at different times and with different endpoints.

Credit: R. L. CIOCHON/UNIV. IOWA

The fossil more closely resembles the jaws of H. erectus in Africa and Western Eurasia than those from China. The researchers suggest that an earlier population of H. erectus took a southern route to equatorial Asia, and a second group took a more northerly passage to northeast China.

J. Hum. Evol. 61, 363–376 (2011)