Woolly rhino found preserved in permafrost after 32,000 years

(CNN) — Scientists have uncovered a woolly rhino so well preserved in the Russian permafrost for more than 32,000 years that its skin and fur are still intact.

This woolly rhino died when it was about four years old and that age, combined with its good state of preservation, has allowed scientists to learn more about the now-extinct species.

“The vast, vast majority of remains from Ice Age animals are bones and teeth without any flesh or skin or anything like that,” Love Dalén, a professor of evolutionary genomics at Stockholm University who wasn’t involved in this study but has studied the remains of other animals found preserved in Siberian permafrost, told CNN.

“There’s probably one in 10,000 or something like that where you run into something like this (rhino). With that said, there are lots of samples coming out of the permafrost every year so it seems to happen almost on a yearly basis.”

The findings from this study, which are detailed in a paper published in the journal Doklady Earth Sciences, revealed that the woolly rhino had a large fatty hump on its back and that its fur changed color as it grew older.

When this woolly rhino roamed eastern Siberia more than 30,000 years ago, it would have “been one of the largest herbivores in the Ice Age ecosystem, second only to the woolly mammoth,” and grazed on the grasslands there, Dalén said.

Like its modern counterparts, the woolly rhino had two horns but one of these was “a very large, blade-shaped horn which is quite unique,” he added, compared with the rounder horns of a modern rhino.

Once this woolly rhino died, it lay frozen in permafrost until a team of Russian scientists from research institutions in Yakutsk and Moscow discovered it in August 2020 on the banks of the Tirekhtyakh River.

The study did not detail exactly how the remains were found but in that area of Siberia, Dalén explained, local Russians tunnel into the permafrost looking for mammoth tusks to sell. As part of an agreement with local authorities in the region where the woolly rhino was found, tusk hunters have to contact paleontologists whenever they discover something of interest like this mummified woolly rhino, meaning that there is a steady stream of well-preserved specimens specifically from this area.

After the animal’s discovery, scientists temporarily defrosted it before taking samples of the fur, skin and the hump for testing. While the rhino’s right side remained well preserved in the permafrost, its left side was so badly damaged that scientists concluded it had been eaten by predators. Its internal organs were exposed and most of its intestines were missing, the study noted.

On its back, scientists observed a hump of up to 13 centimeters (five inches) that was filled with a fatty mass. This is a relatively common feature among Arctic animals, Dalén said, and offers a way to store energy for the winter and to convert energy from food into heat without shivering like humans.

By comparing this specimen, which had light brown fur and a much lighter and softer layer underneath, with others of different ages, the researchers concluded that young woolly rhinos had light, even blond, hair that then became darker and coarser as they reached maturity.

Specimens like this are important for future research, Dalén said, since there are types of genetic tests that can only be conducted on tissue rather than bones.