Two previously unknown species of sabre-toothed cat identified from fossils in South Africa suggest that the African continent may have been an evolutionary hotspot for these long-fanged felines.
Sabre-toothed cats roamed the globe from the Eocene Epoch to the late Pleistocene Epoch, about 56 million to 11,700 years ago. These now-extinct cats included more than two dozen known species identified from fossils on different continents, but researchers are still unravelling which sabre-tooth species lived where and when.
Alberto Valenciano at the Complutense University of Madrid in Spain and his colleagues examined a large collection of fossils found near Cape Town, South Africa. The remains had been unearthed more than four decades prior and included near-complete fragments of the cats’ skulls, jaws and serrated teeth. The researchers created a detailed matrix of different measurements and features of each fossil, which let them contrast sabre-tooths in Africa and around the world.
The comparison revealed two medium-sized sabre-toothed species that were distinct from the others. They named the smaller, jaguar-sized species Dinofelis werdelini. Compared to other members of its genus, D. werdelini had bigger canine teeth, just under 10 centimetres, but smaller teeth on the sides of its mouth. The species’ leopard-like skull shape suggests it was well-adapted to ambushing prey and probably hunted in a forest landscape.
The slender, elongated skull of the larger of the new species, Lokotunjailurus chinsamyae, suggests it was a runner. Valenciano says it probably wasn’t as quick on its feet as a cheetah, but it is likely it was faster than a lion. Because sabre-tooths from this genus had only been found in Kenya and Chad on the continent, experts didn’t expect to find a related cat in southern Africa. “This confirms that this sabre-toothed cat [genus] was on most of the continent,” says Valenciano.
Based on the fossils’ location in layers of earth that build up over time, they suspect both cats lived around 5 million years ago, during the early Pliocene Epoch. That means the sabre-tooths could have overlapped with early hominins, the group from which modern humans evolved.
The researchers also created the first published family tree of Africa’s 13 known sabre-toothed species, which highlights close physical similarities between L. chinsamyae and sabre-tooths from the same genus in southwestern China. That means it could be an example of convergent evolution – when the same traits evolve independently – or it might hint at a migration route between the two places.