Perfectly Preserved Cave Lion Cubs Found In Permafrost Reveal Life Of Extinct Species


Tom Hale


Tom Hale

Senior Journalist

Tom is a writer in London with a Master's degree in Journalism whose editorial work covers anything from health and the environment to technology and archaeology.

Senior Journalist

Cave Lion.

The young cave lion named Sparta is one of the best-preserved Ice Age animals ever discovered. Image Courtsey of Love Dalén

After laying untouched in Siberian permafrost for tens of thousands of years, the incredibly well-preserved bodies of two cubs are now showing scientists how extinct cave lions braced the chill of northern snow-covered landscapes.

A team from the Russian Academy of Sciences and the Centre for Paleogenetics in Sweden, led by Russian researchers Gennady Boeskorov and Alexey Tikhonov, recently took another look at the mummified bodies of two cave lion cubs – nicknamed “Sparta” and “Boris” – discovered a few years ago on the banks of the Semyuelyakh River in Siberia. Their results are published in the journal Quaternary


Researchers published a study on this pair a year ago, revealing that extinct cave lions (Panthera spelaea) were a separate species to the modern-day lions (Panthera leo) found today in sub-Saharan Africa. Genetic analysis suggests the two relatives diverged from each other about 1.9 million years ago.

Now, the team is back with a new analysis of the cubs’ anatomy. Scientists have previously used depictions of animals in cave art, plus comparison with African lions, to understand the appearance of cave lions – but these two cubs allow an unprecedented look at this extinct species. 

Cave lion.
Another image of Sparta, one of the best-preserved Ice Age animals ever discovered. Image Courtsey of Love Dalén

Sparta, formerly Spartak, is said to be the best-preserved Ice Age animal ever discovered. Her golden fur is almost completely undamaged – albeit a little bit matted – and her teeth, skin, soft tissue, and organs remain beautifully preserved. The study notes that the coat hair of a cave lion cub is similar to that of an African lion cub, with cave lions distinguished by long thick fur undercoats that helped them brave the cold climate.

The pair were once thought to be siblings since they were discovered so closely together, but radiocarbon dating has revealed Sparta is 27,962 years old, while Boris is 43,448 years old.


Both cubs died at 1-2 months old, the new study found. There was no evidence of predators or scavengers damaging their remains, but they found the skulls were cracked, ribs broken, and bodies distorted into unusual shapes. From this unusual post-mortem, they suspect the pair died in two separate mudslides, millennia apart. 

The cave lion was widely spread throughout eastern Siberia in the Late Pleistocene period, but evidence of the species has also been found across much of Eurasia and even North America in what is currently known as Alaska.

Like many large animals of the Pleistocene epoch, cave lions slipped into extinction about 14,000 years ago during the last major extinction event at the end of the last Ice Age. Fortunately, however, the sub-zero temperatures of the Siberian permafrost allowed these specimens to remain in remarkably good condition, allowing insights into how they once lived.



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  • tag
  • Ice Age,

  • Siberia,

  • extinct species,

  • felines,

  • cave lions