Ambulocetus

Genus of extinct mammals

Ambulocetus (from Latin ambulō, meaning "to walk", and cetus, meaning "whale", and thus, "walking whale") is a genus of early semiaquatic cetacean from the Kuldana Formation in Pakistan, roughly 48 or 47 million years ago during the Early Eocene (Lutetian). It contains one species, Ambulocetus natans (Latin natans "swimming"), known solely from one near-complete skeleton. Ambulocetus is among the best-studied of Eocene cetaceans, and serves as an instrumental find in the study of cetacean evolution and their transition from land to sea, as it was the first cetacean discovered to preserve a suite of adaptations consistent with an amphibious lifestyle.

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