Ocean Fossil Reveals Clues to Human Ancestry!

A jawbone retrieved from the Taiwan Strait has been confirmed as belonging to a Denisovan, an ancient relative of humans, challenging previous understanding of their geographic range. The fossil, discovered at depths of 60 to 120 meters, suggests Denisovans inhabited warmer climates in Asia, beyond the colder, mountainous regions previously believed.

Denisovan Range Extended to Taiwan Strait

Denisovans were previously known to have lived in Siberia’s Denisova Cave and parts of the Tibetan Plateau. This new discovery indicates they may have roamed a much wider area than previously thought.

Researchers state the fossil’s location, 25 kilometers off the coast of Taiwan, was once part of the Asian mainland during the Pleistocene era, before rising sea levels submerged the area. The climate at that time was warmer and more humid than the cold, dry environments previously associated with Denisovans.

For years, scientists have relied on genetic traces in modern populations to speculate about the range of Denisovans. This fossil provides physical evidence confirming their ability to thrive in diverse environments.

Paleoproteomics Identifies Ancient Species

The fossil was identified using paleoproteomics, a technique that analyzes proteins in ancient bones and teeth. This method was used instead of traditional DNA analysis, which is often difficult with old specimens. Researchers extracted over 4,000 amino acid residues from the fossil’s tooth enamel, identifying two as Denisovan-specific.

“What I think is exciting in this particular study is that we have studied the dental enamel of the teeth as well, and from that, we can deduce that this individual is a male individual,” said Dr. Frido Welker, one of the study’s authors.

Denisovans Were Highly Adaptable

The jawbone demonstrates the adaptability of Denisovans, showing they could survive in varied environments. Dr. Welker noted the regions where Denisovan fossils have been found—the Altai Mountains, the Tibetan plateau, and the warmer Taiwan Strait—highlight their ability to adjust to changing conditions.

“This signals a huge ability to adapt to very different environmental conditions, and survive in all those places,” he said.

The study also revealed that Denisovans had robust mandibles and large teeth, traits potentially aiding survival in harsh environments. However, it remains unclear if these traits were typical of the species or specific to male Denisovans.

“That’s something we’ll need more fossil evidence to confirm,” Dr. Welker said.

While direct dating of the fossil using uranium techniques was unsuccessful, researchers estimate its age to be between 10,000 and 190,000 years old. The combination of paleoproteomics and genetic analysis may eventually help pinpoint when and where Denisovans roamed, according to Dr. Welker.

“With paleoproteomics and genetic methods, I hope that in the future we can better pinpoint where and when that happened.”

This discovery could lead to further revelations about Denisovans, their interactions with Neanderthals and Homo sapiens, and their eventual disappearance.