The fossilized fangs of saber-toothed cats hold clues to how the extinct mammals shared space and food with other large predators 9 million years ago.
Led by the University of Michigan and the Museo Nacional de Ciencias Naturales in Madrid, a team of paleontologists has analyzed the tooth enamel of two species of saber-toothed cats and a bear dog unearthed in geological pits near Madrid. Bear dogs, also extinct, had dog-like teeth and a bear-like body and gait.
The researchers found that the cat species—a leopard-sized Promegantereon ogygia and a much larger, lion-sized Machairodus aphanistus—lived together in a woodland area. They likely hunted the same prey—horses and wild boar. In this habitat, the small saber-toothed cats could have used tree cover to avoid encountering the larger ones. The bear dog hunted antelope in a more open area that overlapped the cats' territory, but was slightly separated.
"These three animals were sympatric—they inhabited the same geographic area at the same time. What they did to coexist was to avoid each other and partition the resources," said Soledad Domingo, a postdoctoral fellow at the U-M Museum of Paleontology and the first author of a paper on the findings published in the Nov. 7 edition of Proceedings of the Royal Society B.
Millions of years before the first humans, the predators lived during the late Miocene Period in a forested area that had patches of grassland. Large carnivores such as these are rare in the fossil record, primarily because plant-eating animals lower on the food chain have outnumbered meat-eaters throughout history.
Cerro de los Batallones, where Domingo has been excavating for the past eight years, is special. Of its nine sites, two are ancient pits with an abundance of meat-eating mammal bones. Agile predators, the researchers say, likely leapt into the natural traps in search of trapped prey.