Durham, NC The toothiest prehistoric predators also had beefier arm bones, finds a new fossil study.
Sabertooth tigers may come to mind, but these extinct cats weren't the only animals with fearsome fangs. Take the false sabertooth cats also known as nimravids and their catlike cousins, a family of carnivores called the Barbourofelidae.
Both of these mammal groups lived millions of years before cats came to be, and had knife-like canines along with well-built arm bones, said author Julie Meachen, a paleontologist at the National Evolutionary Synthesis Center in Durham, NC.
This killer trait combination arose repeatedly in different sabertooth predators over time, Meachen reports in a new study presumably because it gave them an advantage when catching and killing prey.
The long, thin teeth of sabertooth cats look formidable, but they're actually fragile compared to felines living today, she explained. "Cats living today have canines that are shorter and round in cross-section, so they can withstand forces in all directions," Meachen said. "This comes in handy for hunting their teeth are better able to withstand the stress and strain of struggling prey without breaking."
In contrast, the elongated canines of saber-toothed cats were flattened side-to-side and more oval in cross-section, which made them more vulnerable to fracture.
In a previous study published in 2010, Meachen found that the sabertooth cat Smilodon fatalis had exceptionally thick arm bones when compared with its feline cousins. "Thick, robust bones are an indicator of forelimb strength," Meachen said. The results suggest these animals may have relied on their forelimbs to help catch and kill their prey without fracturing their fangs.
But in studying the fossil skeletons of other sabertooth predators, Meachen had a hunch that the combination of fragile knife-like canines and beefy arm bones might not have been unique to saberto
|Contact: Robin Ann Smith|
National Evolutionary Synthesis Center (NESCent)