The most promising fossil found so far, which could be evidence of Denisovans, came from a cave in Tibet: a massive jaw with two powerful molars that is at least 160,000 years old. In 2019, scientists isolated proteins from the jaw, and their molecular makeup suggests they belonged to a Denisovan rather than a modern human or Neanderthal.
This molecular evidence – combined with fossil evidence – suggests that the common ancestors of Homo sapiens, Neanderthals, and Denisovans lived 600,000 years ago.
Our lineage split off on its own, and then 400,000 years ago Neanderthals and Denisovans split up. In other words, Neanderthals and Denisovans were our closest extinct relatives. They even crossed with the ancestors of modern humans, and we now carry bits of their DNA.
But many puzzles still remain from this phase of human history – especially in East Asia. Over the past few decades, paleoanthropologists have found a number of fossils, many of which are incomplete or damaged, and which have some features that make them look like our own species and other features that suggest they are somewhere else in the hominin Family tree.
Katerina Harvati, a paleoanthropologist at the University of Tübingen in Germany who was not involved in the new study, said the dragon man’s skull “could clear some of the confusion”.
To find out how Homo longi fits into the human family tree, the scientists compared its anatomy to 54 hominin fossils. The researchers found that it belongs to a lineage that includes the jaw in Tibet identified as Denisovan.
The skull looked even more like part of a skull discovered in 1978 in Dali County, China, which is 200,000 years old. Some researchers thought the Dali fossil belonged to our own species, while others thought it belonged to an older lineage. Others even named the fossil a new species, Homo daaliensis.