An international team of researchers led by the Swedish Centre for Palaeogenetics has analyzed 31 mitochondrial genome sequences from the cave lion (Panthera spelaea) and found that this extinct mega-carnivore existed as at least two subspecies during the Pleistocene. The scientists have also confirmed that the cave lion and the extant lion (Panthera leo) are distinct species.
The cave lion was an apex predator widespread across the Holarctic until their extinction at the end of the Pleistocene period.
It was larger than its modern counterpart, and Pleistocene cave art suggests that it did not have a mane.
However, it may have shared several behavioral traits with the lion, such as group living and courtship rituals.
The timing of the divergence between the extinct cave lion and the extant lion is controversial.
“The cave lion was one of the most common large predators during the last Ice Age, with a distribution throughout northern Eurasia and North America. It became extinct about 14,000 years ago,” said Professor Love Dalén, an evolutionary geneticist at the Centre for Palaeogenetics.
In the study, Professor Dalén and colleagues investigated mitochondrial genome diversity in 31 cave lions, including a well-preserved cave lion cub named Spartak, from across their entire prehistoric range.
“Spartak had been frozen for 28,000 years before it was discovered and is probably the best-preserved Ice Age animal ever found,” they said.
They identified two deeply diverged subspecies and an additional third distinct lineage represented by a single individual.
One of these subspecies lived in Beringia (Yakutia, Alaska and Yukon Territory) while the other was prevalent across western Eurasia.
This geographical distribution is consistent with previous findings that cave lion skulls and jaws from Beringia are significantly smaller than those from Europe.
In addition, it is likely that Beringian and European cave lions had different prey preferences, with the former focusing on bison and horses, and the latter on reindeer.
The results also show that cave lions diverged from present-day lions about 1.85 million years ago and subsequently split into two different subspecies roughly 500,000 years ago.
“Our study suggests that the cave lion was indeed a distinct species, separated from the modern lion,” said Dr. David Stanton, a researcher in the Centre for Palaeogenetics and the Department of Bioinformatics and Genetics at the Swedish Museum of Natural History.
“The analyses also support the theory that the cave lion was divided into an eastern and a western subspecies.”
The findings were published in the journal Scientific Reports.
D.W.G. Stanton et al. 2020. Early Pleistocene origin and extensive intra-species diversity of the extinct cave lion. Sci Rep 10, 12621; doi: 10.1038/s41598-020-69474-1