Fossils: Ancient enamel sheds light on extinct giant ape

An analysis of dental enamel from an extinct giant ape species, Gigantopithecus blacki, is reported in Nature this week. The research may aid our understanding of great ape evolution and diversification.

G. blacki is an extinct giant ape, which was first identified in 1935 based on a single tooth sample and is thought to have lived in Southeast Asia during the Pleistocene period (around 2,000,000 to 300,000 years ago). Numerous G. blacki teeth and four partial mandibles have been identified but the absence of cranial remains has meant its relationship to other great ape species and its divergence from them has been hard to determine.

Frido Welker and colleagues analyse a 1.9-million-year-old fossil molar from G. blacki discovered in Chuifeng Cave, China. The authors recovered ancient enamel proteins from the sample and suggest that the molar may have belonged to a female G. blacki. Further analysis indicates that Giganthopithecus is a sister group to orangutans with a common ancestor around 12 - 10 million years ago. This finding places the divergence of Giganthopithecus in the Middle or Late Miocene epoch.

The authors suggest that these are the oldest known skeletal proteins sequenced to date. They propose that the survival of ancient enamel proteins from a subtropical specimen expands the scope of proteome analysis into geographical areas and time periods that have previously been thought to be incompatible with the technique.