Finds from Taiwan and Israel shed light – and confusion – on the story of ancient human species.
Find 1: A mysterious jawbone from Penghu, Taiwan
Discovered by chance by fishermen off the coast of Taiwan, an unusually thick and primitive human jawbone shows a challenging mix of features. While no DNA has yet been recovered from the specimen, its characteristics make it difficult to classify into existing groups.
The jawbone is short and wide, with a thick body and large teeth. It dates within the last 450,000 years, and most likely within the last 200,000.
The jawbone, left, and a reconstruction of the jaw, right © Yousuke Kaifu.
A partial Homo erectus skull from the Chinese mainland has some large associated teeth and could be 400,000 years old, so the new jawbone may belong to the same group. But it could also be one of the elusive ‘Denisovans’, a group known only by DNA from a fragmentary fossil finger bone and two very large molar teeth in a Siberian cave.
Museum human origins expert Prof Chris Stringer said this could be an interesting development:
I have considered the Denisovans as an Asian sister group of the Neanderthals, and like them, derived from Homo heidelbergensis, but if Penghu is indeed a long-awaited Denisovan jawbone, it looks more primitive than I would have expected.
He said of the find:
As the authors note, this enigmatic fossil is difficult to classify, but it highlights the growing and not unexpected evidence of human diversity in the Far East, with the apparent co-existence of different lineages in the region prior to, and perhaps even contemporary with, the arrival of modern humans some 55,000 years ago.
Find 2: The skull of a possible early migrant, from northern Israel
A later and much better-dated specimen, the partial skull of an early modern human from Manot Cave dates to a time of migration out of Africa and interbreeding with Neanderthals. At about 55,000 years old, it sits comfortably in the timeframe estimated for early modern human and Neanderthal interbreeding, 50-60,000 years ago.
The skull itself has characteristics indicative of early modern humans, and without DNA it is impossible to say yet whether interbreeding with Neanderthals had an impact on the individual. Nonetheless, Prof Stringer said it is a critical find for examining possible migrant populations:
Manot might represent some of the elusive first migrants in the hypothesised out-of-Africa event about 60,000 years ago, a population whose descendants ultimately spread right across Asia, and also into Europe. Its discovery raises hopes of more complete specimens from this critical region and time period.
Related human origins posts: