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What sharp teeth!
The saber-toothed cat may be the most famous saber-toothed animal, but it's hardly the only one. More than a dozen kinds of animals — many of them now extinct — had saber teeth, including the saber-toothed salmon and the marsupial Thylacosmilus.
Today, saber-toothed animals include the walrus, musk deer and warthog, all of which grow incredibly long and sharp canines, the hallmark of a saber tooth. (Elephant tusks are long incisor teeth, and thus are not sabers.)
It's unclear how ancient animals used their saber teeth. Some experts think predators used these knifelike teeth to hunt and kill, slicing the neck vertebrae and spinal cords of prey, said Ross MacPhee, a curator of mammalogy at the American Museum of Natural History (AMNH) in New York City. [Big Bites: Saber Teeth Compared (Infographic)]
"[But] to me, this is totally improbable," MacPhee told Live Science. "The blades in Thylacosmilus are actually very thin, and neck vertebrae in ungulates are surrounded by tough muscles and ligaments. The teeth would have broken as the prey bucked around."
Instead, perhaps the sabers helped predators tear away at the prey's belly. "This is normal procedure for big placental cats," MacPhee said. "Cutting into the belly tends to bring the prey down on its knees so that it is easier to move in to crush their windpipes."
He added, "Sorry for the graphic details, but this is what happens, and it is supremely effective."
Here's a look at 12 living and extinct saber-toothed animals.
Musk deerSlide 2 of 25
The musk deer (Moschus moschiferus) is one of the few saber-toothed animals living today. But it doesn't use its long canines for meaty prey — the ungulate is an herbivore, said Jack Tseng, a paleontologist at the AMNH.
"The males have these long sabers to fight each other during the mating season," Tseng told Live Science. "The reason you have such an over-the-top appearance is mating purposes, either to fight males or to impress females."Slide 3 of 25
WalrusSlide 4 of 25
The walrus (Odobenus rosmarus) has one of the longest sabers on record, with some males sporting canines extending more than a foot (0.3 meters) in length. Male walruses use their sabers both as a display and a weapon, Tseng said.
The sabers serve a variety of purposes. These long canines help them with "tooth-walking," or pulling their large bodies out of the water; breaking breathing holes in ice while swimming in the water below; and protecting their territory and harems, according to National Geographic.
Walruses may also use their sabers to help them stir up underwater sediment to search for mollusks, such as clams, Tseng said. But it's hard to say for sure — underwater photography is murky at best.
"As soon as the walrus hits the [sea] floor and starts to dig around, everything is just a blur," Tseng said.Slide 5 of 25
Saber-toothed salmonSlide 6 of 25
The saber-toothed salmon's teeth weren't oriented in a vertical saber-tooth fashion, but stuck out the sides of the fish's mouth like a scythe, said Edward Davis, the curator of fossil collections for the University of Oregon Museum of Natural and Cultural History, and an assistant professor of geology at the University of Oregon.
In fact, few experts call the fish (Oncorhynchus rastrosus) a saber-toothed animal anymore. Instead, researchers favor the names "spike tooth" and "giant salmon," because it was more than 6.5 feet (2 m) long and weighed about 660 lbs. (300 kilograms), he said.
O. rastrosus lived in the Pacific during the late Miocene and possibly the early Pliocene, from about 13 million to 4 million years ago. The filter feeder likely used its long teeth to fight for access to mates, slashing sideways at rival males, Davis said.
"[But] it is possible both sexes had these teeth, with females fighting for the best sites to make their nests, called redds," Davis said.Slide 7 of 25
Extinct WalrusSlide 8 of 25