14,000-year-old hominin thigh bone has archaic affinities.
In 2012, human remains differing from the modern condition were reported from two sites 300 km (185 miles) apart in southwest China: Longlin Cave in Guangxi Province, and Maludong (‘Red Deer Cave’) in Yunnan Province. The Longlin remains have been radiocarbon dated to 11,500 years old, and those from Maludong to 14,000 years old. The Longlin remains included a partial skull, a temporal bone fragment probably belonging to the skull, a partial lower jawbone and some fragmentary postcranial bones. The cheek bones of the skull are broad and flared sideways; the browridges conspicuous; the chin less prominent than in Homo sapiens; and the remains are very robust. The Maludong remains include a skullcap, two partial jawbones and a partial thighbone.
Popularly reported as the Red Deer Cave people, the hominins were at first thought to represent a single population, but newly-published work suggests that the Longlin skull has affinities to early modern humans. The bony labyrinth (the bony outer wall of the inner ear) of the temporal bone fragment is modern in appearance and it is possible that the skull’s unusual shape might be the result of interbreeding between archaic and modern humans. It has been suggested that Longlin was located in a ‘hybrid zone’ – a border between relict archaic and modern populations. Similar hybrid zones occur with some non-human primate populations.
The Maludong thighbone is now claimed to show affinities to archaic humans, in particular those from the Early Pleistocene. There is a scarcity of later archaic human remains in East Asia, and the authors of the new report are reluctant to assign the thighbone to a particular archaic human species. However, the likeliest possibility is that the thighbone represents a late survival of Homo erectus in China. Regardless of species, the implications of these new findings is that isolated populations of archaic humans were still in existence in China as late as 11,500 years ago and that some of these populations were interbreeding with modern humans.
1. Curnoe, D. et al., Human Remains from the Pleistocene-Holocene Transition of Southwest China Suggest a Complex Evolutionary History for East Asians. PLoS One 7 (3) (2012).
2. Curnoe, D., Ji, X., Taçon, P. & Yaozheng, G., Possible Signatures of Hominin Hybridization from the Early Holocene of Southwest China. Scientific Reports 5, 12408 (2015).
3. Curnoe, D. et al., A Hominin Femur with Archaic Affinities from the Late Pleistocene of Southwest China. PLoS One (2015).