Next, continuing with my theme of obsession with mammal skulls, are some prehistoric whale skulls.
First is Pakicetus, a carnivorous land mammal that lived about 49 million years ago.
Next is another early whale ancestor, Ambulocetus, from about the same time. Ambulocetus had already begun the transition from land to water and almost certainly spent time in both.
This is Basilosaurus, a large, fully aquatic whale from about 35 million years ago.
And, finally, a quick life sketch of Basilosaurus, which, despite the name, was a whale and not a dinosaur. The people that discovered it were dumb.