アメリカ自然史博物館さんのインスタグラム写真 - (アメリカ自然史博物館Instagram)「Smile like Smilodon, because it’s Fossil Friday! This saber-tooth cat roamed the Americas during the Pleistocene, until its extinction some 10,000 years ago. Scientists estimate that its signature teeth, which could reach lengths of 7 in (18 cm), grew at the rapid speed of .24 in (6 mm) per month—double the growth rate of an African lion’s teeth. To unsheathe these knife-like canines, Smilodon could open its jaws twice as wide as today’s big cats. You can spot this fearsome predator in the Museum’s Hall of Primitive Mammals. Photo: © AMNH #paleontology #smilodon #prehistoric #megafauna #biodiversity #amazinganimals #didyouknow」9月1日 22時59分