Proteins In Hominin Fossil In Taiwan Are Denisovan

While the jaw bone still isn't enough to develop much of an image of what Denisovans looked like, this is definitely a major, although not unexpected, development. Denisovan admixture in modern humans had already strongly suggested a broad range for them in Asia, even though this is the first definitively identified Denisovan bone sample from comparatively warm regions in southern Asia.

A fossilized jawbone found off the coast of Taiwan more than 20 years ago belonged to a group of ancient humans, called the Denisovans, first identified in a Siberian cave.

The finding, published today in Science1, is the result of time-consuming work to extract ancient proteins from the fossil. It also expands the known geographical range of the group, from colder, high-altitude regions to warmer climates.

“I’m very excited to see this,” says Janet Kelso, a computational biologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

The lower jawbone, with four teeth intact, is called Penghu 1 and was dredged up by fishing crews from the Penghu channel, 25 kilometres off the west coast of Taiwan. Penghu 1 was donated to Taiwan’s National Museum of Natural Science in Taichung after researchers recognized its significance as coming from an ancient human relative2. But the identity of that unknown relative remained a mystery, until now.

Ancient proteins

Researchers spent more than two years carefully refining techniques for extracting ancient proteins from animal bones taken from the channel. They then used acid to isolate protein fragments from the surface of a Penghu 1 molar tooth and enzymes to extract them from the jawbone.

The team identified several degraded fragments, two of which bore specific amino-acid sequence variations matching those seen in the genetic sequences of a Denisovan finger bone3 found in the Denisova Cave in southern Siberia in 2008. The researchers could also tell that the jawbone came from a male Denisovan.

It’s the second location that molecular evidence from ancient proteins has definitively linked fossil remains to the Denisovans. The first was in a cave in Xiahe, Tibet where proteins from a jawbone4 and then a rib bone were determined to be from Denisovans.

Pinning down an exact age for the Penghu fossil is challenging because scientists do not have samples of the sediment it was buried in.

“One can only say it’s older than 50,000” years, says Rainer Grün, a geochronologist at the Australian National University in Canberra, who dated the fossil in 2015 and subsequently reanalysed the data5.

The Xiahe 1 mandible is at least 160,000 years old, and material from the Denisova cave indicates that Denisovans lived in Siberia between 200,000 and 50,000 years ago. At that time, sea levels were lower and the Chinese mainland was connected to Taiwan.

From here. 

The paper and its abstract are as follows:

Editor’s summary

Denisovans are a Pleistocene hominin lineage first identified genomically and known from only a few fossils. Although genomic studies suggest that they were widespread throughout Asia, fossils of this group have thus far only been identified from regions with cold climates, Siberia and Tibet. 

Tsutaya et al. used ancient proteomic analysis on a previously unidentified hominin mandible from Taiwan and identified it as having belonged to a male Denisovan. This identification confirms previous genomic predictions of the group’s widespread occurrence, including in warmer climates. The robust nature of this mandible is similar to that seen in a Denisovan one from Tibet, suggesting that this is a consistent trait for the lineage. —Sacha Vignieri

Abstract

Denisovans are an extinct hominin group defined by ancient genomes of Middle to Late Pleistocene fossils from southern Siberia. Although genomic evidence suggests their widespread distribution throughout eastern Asia and possibly Oceania, so far only a few fossils from the Altai and Tibet are confidently identified molecularly as Denisovan. 

We identified a hominin mandible (Penghu 1) from Taiwan (10,000 to 70,000 years ago or 130,000 to 190,000 years ago) as belonging to a male Denisovan by applying ancient protein analysis. We retrieved 4241 amino acid residues and identified two Denisovan-specific variants. The increased fossil sample of Denisovans demonstrates their wider distribution, including warm and humid regions, as well as their shared distinct robust dentognathic traits that markedly contrast with their sister group, Neanderthals.

Takumi Tsutaya, et al., "A male Denisovan mandible from Pleistocene Taiwan" 388 (6743) Science 176-180 (April 11, 2025). Hat tip to Neo in the comments.