MOSASAURUS
Mosasaurus was a type of large, carniverous, aquatic lizard. It was technically not a dinosaur, but a reptile closely related to snakes and monitor lizards. Mosasaurus grew up to 50ft (15m) long and existed for about 4 million years until the mass extinction event that ended the Mesozoic period.
It lived from about 82 to 66 million years ago during the Campanian and Maastrichtian stages of the Late Cretaceous. The earliest fossils of Mosasaurus known to science were found as skulls in a chalk quarry near the Dutch city of Maastricht in the late 18th century, which were initially thought to have been the bones of crocodiles or whales.Fossil evidence suggests Mosasaurus inhabited much of the Atlantic Ocean and the seaways adjacent to it. Continents where Mosasaurus fossils have been found include North America, South America, Europe, Africa, Western Asia, and Antarctica. This distribution encompassed a wide range of oceanic climates including tropical, subtropical, temperate, and subpolar climates. Mosasaurus was a common large predator in these oceans and was positioned at the top of the food chain. Paleontologists believe its diet would have included virtually any animal; it likely preyed on bony fish, sharks, cephalopods, birds, and other marine reptiles including sea turtles and other mosasaurs. It likely preferred to hunt in open water near the surface. From an ecological standpoint, Mosasaurus probably had a profound impact on the structuring of marine ecosystems; its arrival in some locations such as the Western Interior Seaway in North America coincides with a complete turnover of faunal assemblages and diversity.
