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)「Do you know what an artiodactyl is? A hoofed mammal with an even number of toes! Meet Blastoceros pampaeus, an artiodactyl (and a deer) that lived in modern-day Argentina around 30,000 years ago during the Pleistocene. All artiodactyls have an ankle bone that allows rotating movement at both its top and bottom. This “double-pulley” ankle enhances motions used in leaping and bounding. You can see this specimen on the Museum’s fourth floor! Photo: © AMNH」5月30日 11時55分