First Denisovan forearm bone found in Chinese cave

Two international research teams announced Wednesday the discovery of seven Denisovan fossils and more than 1,300 stone tools at a cave site in southwestern China, offering the most detailed window yet into how these extinct ancient humans lived and survived.

The fossils — four teeth, two skull fragments, and the first-known Denisovan forearm bone — were recovered from Bianfu Cave in Yunnan Province, near China's borders with Myanmar and Laos. The remains date to between 167,000 and 134,000 years ago, while the stone tools span an even wider range, from 190,000 to 70,000 years ago, according to two papers published Wednesday in Nature.nature

A Cave Rescued From Destruction

The discovery was an unlikely one. In 2019, an ecological restoration project at an abandoned limestone quarry uncovered the buried cave and its trove of fossils. "Most of the cave had already been destroyed," said Qingfeng Shao, a geochronologist from Nanjing Normal University who contributed to both studies.nationalgeographic

Denisovans were first identified in 2010 from DNA extracted from a finger bone found in a Siberian cave. Since then, only a handful of fossils have surfaced at a total of five sites. The Bianfu Cave find now represents the richest Denisovan fossil record outside Siberia's Denisova Cave.eurekalert

Because no DNA could be extracted from the remains, researchers used a novel strategy combining morphological screening of more than 60,000 bone fragments with proteomic analysis. All five specimens carried a Denisovan-specific collagen variant, confirming their identity. "I am quite convinced that these are Denisovan remains," said Svante Pääbo, the evolutionary geneticist whose lab first sequenced Denisovan DNA but was not involved in the new study.nationalgeographic+1

Tools and Hunting

The cave also contained over 1,600 identifiable animal remains, mainly deer and other ruminants, many bearing cut marks consistent with butchering. The tools — scrapers, choppers, hammerstones, and bone implements — suggest a practical, impromptu approach to toolmaking. Denisovans appear to have knocked sharp flakes from stones, used them, and discarded them, rather than crafting the more refined tools associated with later Homo sapiens.sciencenews+1

The recovered forearm bone, a partial radius, revealed that Denisovans' biceps attachment point was positioned differently than in modern humans, allowing them to generate more twisting force for the same muscle size. The skull fragments were notably thick — 0.3 to 0.4 inches — more closely resembling Homo erectus and Neanderthals than modern humans.nationalgeographic

Filling a Geographic Gap

The site fills a long-standing gap in the known distribution of Denisovans across southern Asia. "Denisovans are becoming a bit less mysterious," said Shara Bailey, a paleoanthropologist at New York University. The cave tells researchers that Denisovans adapted to varied environments, hunting different prey in different regions — marmots in colder northern sites, deer and buffalo in Yunnan's milder climate.sciencenews

Denisovan DNA persists in many living populations, particularly among Indigenous peoples in the Philippines, Papua New Guinea, Australia, and Tibet, where an inherited gene aids survival at high altitudes.cnn+1