Jurassic “Beaver” Found; Rewrites History of Mammal
A beaverlike tail, seal-esque teeth, and positively platypus-ian ankle spurs make Castorocauda lutrasimilis one original animal, as shown in this artist’s conception.
The semiaquatic mammal ancestor lived about 164 million years ago. Until its recent discovery, Jurassic-period mammals were thought to be only small, shrew-like land dwellers.
Despite similarities with some modern animals, the Jurassic mammal has no modern descendants and is not related to any existing species. The discoverers have given it the name Castorocauda lutrasimilis, Latin for beaver tail and similarity to the otter.