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)「It’s Fossil Friday, so slither into the weekend with Boavus idelmani! Because of snakes’ delicate skeletons, good snake fossils are quite hard to come by. This specimen is from the Green River Formation of western North America, a rock unit renowned for the quality of its preserved fossils. Boavus is a small, early member of the Booidae—a large group of less advanced snakes that includes today’s boas and pythons. This ancient constrictor lived during the Middle Eocene some 50 million years ago. You can see it up close in the Museum's Hall of Vertebrate Origins. Photo: M. Pelczar / © AMNH #fossils #paleontology #history #naturalhistory #amnh #didyouknow」7月7日 23時17分