Mosasaur Teeth

Mosasaur Teeth are large and impressive fossils. They come from a family of large marine reptiles with paddle like fins. They were strong swimmers who roamed the Cretaceous seas as the dominant predators. They ranged in size from the smallest Carinodens belgicus about 10 feet (3 meters) to the largest Tylosaurus and Hainosaurus that could be over 48 feet (15 meters). The mosasaur who owned the fossilized skeleton pictured below, lived during the Cretaceous Period and grew to be 20 to 30 feet long. During the Cretaceous Period large warm seas covered parts of North America and Europe, and mosasaur fossils have been found in North America, Europe, and North Africa. They were fierce predators whose primary prey was fish. There is evidence that they also ate ammonites.
fossilized mosasaur skeleton

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The mosasaur is a group of large, extinct sea reptiles. They were not dinosaurs, even though their name might make you think they were. Mosasaurs lived during the late Cretaceous Period, about 100 million years ago and lasting until 65 million years ago. There were many types of mosasaur. As a classification group, the Mosasauridae is a Family. The Family is divided into subfamilies and many genus and species based on differences in their bodies. There were many different species of of mosasaur. Some were only 1 to 2 meters long or 3 to 6 feet. Most mosasaurs were big animals. One of the largest fossil mosasurs is the Tylosaurus. They could be as long as 15 meters or more than 49 feet! Of course there were all sizes in between these two extremes.

During the Cretaceous Period, the climate was warm and the sea levels were high. There were no ice caps at the poles as there are today. Many parts of the continents were covered with water. Mosasaurs lived in these warm sea waters. In North America, the middle part of the continent was covered by an inland sea. Fossils of mosasaurs have been found in the modern-day Kansas, as well as Nebraska, Alabama, Mississippi, New Mexico, Colorado, California, Montana and North and South Dakota. Mosasaur fossils have even been found as far north as the provinces of Manitoba and Saskatchewan in Canada. They have also been found in Europe and Africa.

Mosasaur bodies were especially suited to living in the warm sea waters around the globe. They had four flippers that helped them be strong swimmers. They had a body shape like a Monitor Lizard, but it was long and sleek to help it move easily through the water. In fact, the mosasaur is a reptile that stayed in the water for its entire life. Most reptiles that live in the sea return to lay eggs on the shore, but the mosasaur gave birth to live babies in the water.