Basilosaurus rules the Eocene seas
An eighteen-metre serpentine whale with useless little back legs becomes the ocean's top predator.
- When
- —
- Duration
- 7 million years
- Known to
- ± 1 million years
- Era
- Eocene, Cenozoic
Basilosaurus is fully aquatic, enormously elongated, and so unlike a mammal in first impression that its describer in 1834 took it for a reptile and gave it a name meaning king lizard — which, under the rules of nomenclature, it is stuck with. Bite marks and stomach contents show it preyed on the smaller whale Dorudon, including juveniles. Its vestigial hind limbs, a few tens of centimetres long on an eighteen-metre animal, are among the most quoted pieces of evidence for evolution in the fossil record.