‘Dragon Man’ skull may help oust Neandertals as our closest ancient relative

By | June 25, 2021

A fossil skull nicknamed “Dragon Man” has surfaced in China under mysterious circumstances, with big news for Neandertals. Dragon Man belonged to a previously unrecognized Stone Age species that replaces Neandertals as the closest known relatives of people today, researchers say.

A nearly complete male skull now housed in the Geoscience Museum of Hebei GEO University in Shijiazhuang, China, represents a species dubbed Homo longi by Hebei GEO paleoanthropologist Xijun Ni and his colleagues. The scientists describe the skull, which dates to at least 146,000 years ago, and analyze its position in Homo evolution in three papers published June 25 in The Innovation.

Qiang Ji, a paleontologist also at Hebei GEO, received the skull in 2018 from a farmer who said the fossil had been dug up by a coworker of his grandfather’s in 1933. During bridge construction over a river in Harbin, China, the worker allegedly scooped the skull out of river sediment. Whether or not that story is true, this fossil could help answer questions about a poorly understood period of human evolution.

“The Harbin cranium presents a combination of features setting it apart from other Homo species,” Ji says. The name H. longi derives from a Chinese term for the province where it was found, which translates as “dragon river.” That term inspired the nickname Dragon Man.

As in H. sapiens, the Harbin skull held a large brain situated atop a relatively short face and small cheek bones. But traits such as a long, low braincase, thick brow ridges, large molars and almost square eye sockets recall several extinct Homo populations or species, including Neandertals and H. heidelbergensis (SN: 4/1/20). Those species date to a key period of Homo evolution called the Middle Pleistocene, which ran from about 789,000 to 130,000 years ago.

Measures of the decay of radioactive uranium in the Harbin skull provided its minimum age estimate of 146,000 years. Chemical analyses of the fossil and sediment still attached to it indicate an origin in the Harbin area, even if the researchers can’t confirm the farmer’s story to Ji.

An artist’s reconstruction shows an adult male, based on a nearly complete fossil skull, who belonged to a newly proposed Homo species that lived at least 146,000 years ago in what’s now northern China.Chuang Zhao

The researchers estimated Dragon Man’s evolutionary status using statistical comparisons to other Middle Pleistocene Homo fossils from Africa, Asia and Europe. These comparisons indicated that H. longi shared a common ancestor with H. sapiens around 949,000 years ago, while the common ancestor of Neandertals and H. sapiens dated to just over 1 million years ago. If so, then H. longi had a slightly closer evolutionary relationship to H. sapiens than Neandertals did.

Ni’s team concludes that H. longi was a contemporary of evolving Asian lines of H. sapiens, Neandertals and Denisovans, a population known mainly from ancient DNA (SN: 12/16/19). The Harbin skull most closely resembles several other Middle Pleistocene Homo fossils from Chinese sites, the researchers say. Some of those finds are now regarded as Denisovans (SN: 10/29/20).

Attempts will be made to extract DNA from and identify the protein structure of the Harbin skull for comparison to Denisovans, says Chris Stringer, a paleoanthropologist at the Natural History Museum in London and a member of Ni’s team (SN: 5/1/19).

Analyses of the geographic distribution of various skeletal traits in Middle Pleistocene Homo fossils indicate that relatively small groups from various species and populations traveled within Africa, Asia and Europe, sometimes interbreeding. Ni’s team suspects that groups based in southern areas, where they could survive during periods of extreme cold, ventured farther when temperatures warmed. Treks were made back and forth across continents, most often from Africa to Asia, the investigators say. Some groups died out along the way, while others eventually passed on genes and skeletal traits over great distances, they suspect.

That scenario seems likely, especially given the surprising mix of features on the Harbin skull, says paleoanthropologist Katerina Harvati of Eberhard Karls University of Tübingen in Germany, who did not participate in the new studies.

Homo groups frequently traversed what’s now northern China as temperatures warmed and rainy periods fluctuated after around 300,000 years ago, says paleoanthropologist Sheela Athreya of Texas A&M University in College Station, who also was not involved in the new studies.  But she argues that the Harbin skull looks much like several other Middle Pleistocene Homo fossils from northern China and shouldn’t be classified as a new species.

Ancient Homo groups on the move evolved unique features during periods of isolation and shared features during periods of contact and mating, she proposes. Intermittent connections across vast areas created closely related populations that inherited varying sets of traits. The Harbin skull and newly described Israeli fossils, classified only as Nesher Ramla Homo, display anatomical variations on a Middle Pleistocene Homo theme, Athreya says (SN: 6/24/21).