Boris, the little male, was found in 2017 when Boris Berezhnev, a local resident and licensed collector of mammoth tusks, was looking for mammoth tusks along the Semyuelyakh River in Siberia. The little one is about 43,448 years old.
A year later, in 2018, a female was found about 15 meters away. Researchers named her Sparta and she is around 27,962 years old. The two cubs were discovered about 10 to 12 meters deep and are about the size of an adult domestic cat. The cubs were only one or two months old when they were mummified.
Researchers identified the two cubs as cave lions in a research paper published on August 4. Cave lions lived in Europe and Asia until their extinction around 10,000 years ago. These two specimens are particularly important because of their state of good preservation.
“It’s important to find intact frozen specimens like this,” Professor Love Dalen, a research team member at the Center for Paleogenetics at Stockholm University, told CBS News. “It allows us to discover new things about extinct species, like the color of their fur… these frozen animals often have excellent DNA preservation, allowing us to investigate the genomes of extinct animals.
“The little one named Sparta is particularly unique because it is possibly the best-preserved ice age specimen ever found,” said Dalen.
Because they were frozen in ice, the color of their fur seen in photos taken after their discovery is likely the same as when they were alive.
Cave lions are similar to modern African lions, but they “likely diverged from modern lions around 1.85 million years ago,” says Dalen.
“They were up to 20% larger than modern lions, and the males may not have had manes. The cave lion was probably adapted to cold environments and was a prominent predator in the mammoth steppe ecosystem. “
Cave lions are especially interesting because of the number of prehistoric paintings depicting them – paintings that actually helped researchers learn more about the anatomy of the extinct animal.
“The cave paintings only show lions without manes,” says Dalen. “So a hypothesis based on rock art is that the males lacked mane, something that we can possibly test using genetic methods in the future. ”
While the researchers say it is “very difficult” to determine what killed the two cubs, it is clear that they were not killed by predators. There is also no evidence that the scavengers had access to the cubs after they died, as there are no teeth marks on the remains.
This indicates that they may have been buried under ice shortly after their deaths. One possibility suggested by the researchers is that a landslide has buried their dens. Both cubs suffered skull damage and dislocated ribs, which supports this theory.
Two more lion cubs had previously been discovered in the same river basin, leading researchers to believe the area was a preferred breeding site for cave lions.