Dogs and cats have never been the best of friends, but 9 million years ago, their ancient counterparts at least lived in harmony together. In ancient Spain, two alpha predators—the saber-toothed cat and the bear dog—shared food and living space, according to new research that takes a hint from the animals’ fossilized teeth.
To arrive at this conclusion, researchers excavated the remains of both leopard-sized saber-toothed cats and lion-sized bear dogs from pits in central Spain. The agile predators likely jumped into the pits in search of food, which acted as natural traps.
National Geographic explains how the teeth came into play:
The researchers took a special interest in the fossilized teeth they found and analyzed them to determine the creatures’ eating habits. They sampled teeth from 69 specimens, including 27 from the saber-toothed cats and bear dogs and the rest from plant eaters.
Using stable carbon isotope analysis, the team was able to determine what the creatures were eating. The data from the herbivores was used first to determine what kinds of plants were available and then to reconstruct the creatures’ environment (woodlands with some open, grassy areas). When the predators’ teeth were analyzed, the data suggested that they were all likely living in the same habitat while feeding on different sized prey.
The researchers think the cats mainly stuck with a diet of horses and wild boar, while the dogs probably preferred antelope. Though the hunting territories overlapped, prey were abundant enough and the forest large enough to prevent much conflict between the predators. Try telling that to the cats and dogs of today, however, who for the most part apparently lost that propensity somewhere along the evolutionary road.
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