There are several reasons why many people think of the Smilodon genus when they think about saber-tooth cats, even if they're not familiar with the scientific name. One is the wealth of Smilodon fossils, which has given scientists and museums lots of material for study. Most of these fossils were found in the Rancho La Brea tar pits in California. Saber-tooth cats are one of the most common mammal fossils found in this naturally-occurring tar. However, in spite of the wealth of saber-tooth fossils found there, entrapment in the tar wasn't all that common. The fossils in La Brea accumulated over about 25,000 years.
Smilodon cats are also well known because they're the saber-tooth cats that lived on Earth most recently. They shared the planet with other familiar ice-age mammals like woolly mammoths, mastodons and ground sloths. All these animals were extinct by about 10,000 years ago due to a number of factors, including climate change, terrain change and human hunting. The Smilodon cats most likely became extinct because their primary source of food -- mammals that were larger than the cats themselves -- died out. The cats weren't fast or agile enough to catch smaller prey, leading to their eventual extinction.
Another genus of saber-tooth cat lived at the same time as the Smilodon variety. These were the Homotherium cats, which had shorter, flatter teeth. Some paleontologists describe them as scimitar cats. These cats had a slightly larger range than the Smilodon genus. Homotherium cats lived in Africa, Europe, Asia and North America. They became extinct about 11,500 years ago.
Researchers have found much older saber-tooth cats in several clay-lined caves near Madrid, Spain. Like the La Brea tar pits, these caves have provided scientists with lots of well-preserved fossil samples. The cats found there are from the genus Paramachairodus -- oldest genus of saber-tooth cats on the planet -- and the genus Machairodus. These were large cats, but their teeth were shorter than those of the Smilodon genus. These cats lived around 9 million years ago.
These are just a few of the many extinct carnivores that have evolved saber teeth. There are no saber-tooth cats alive today, but there are a few animals with dramatically long canine teeth. One example is the walrus, which uses its long tusks for everything from social displays to moving on ice. But although these are modified canines, they aren't quite the same as saber teeth because they're rounded rather than flattened from side to side. However, as living species go, they may be the closest thing you'll see to a pair of saber teeth.
Follow the links on the next page to find lots more resources on saber-tooth cats, fossils, dinosaurs and other extinct animals.