Mosasaurs take the oceans
Lizards return to the water and, within thirty million years, become the sea's top predators.
- When
- —
- Duration
- 26 million years
- Known to
- ± 2 million years
- Era
- Cretaceous, Mesozoic
Mosasaurs descend from monitor-lizard relatives that enter the sea in the mid-Cretaceous, and they adapt fast: paddle-like limbs, a downturned tail fluke, and live birth at sea. They fill the niche vacated by the declining ichthyosaurs and pliosaurs, and the largest reach fifteen metres. The first mosasaur skull, found in a Dutch chalk quarry in the 1760s and seized by the French army in 1795, was central to Cuvier's argument that species could go extinct — the animal that helped prove extinction is real.