Crocodiles

Crocodiles

Crocodiles are fancy. Perhaps too fancy. That is, they have certain features, like a four-chambered heart, that seem unnecessary. This post hypothesizes that crocodiles could have decended from warm-blooded creatures for whom these features were necessary.

An interesting side issue: "[Crocodile] bones have the characteristic richly vascularized structure of fibrolamellar bone, one of the hallmarks of endothermy and one of the pieces of evidence that dinosaurs were warm blooded. Interestingly, one bit of counter evidence used against the hot-blooded dino hypothesis was the fact that crocodilians have the same structure…maybe there's another reason for the similarity, that crocs are also descended from hot-blooded ancestors."