Plesiosaurs were marine reptiles that lived during the Mesozoic Era. They were characterized by their long necks and four flippers. Plesiosaurs were predators that fed on fish, squid, and other marine creatures.
Reproduction
Plesiosaurs reproduced by laying eggs. The eggs were likely laid on land, and they were covered in a hard shell. The eggs hatched after several months, and the young plesiosaurs were left to fend for themselves.
Growth and Development
Plesiosaurs grew quickly, and they could reach lengths of up to 50 feet. They had a relatively short lifespan, and most plesiosaurs only lived for about 20 years.
Diet
Plesiosaurs were carnivores that fed on a variety of marine creatures. Their diet included fish, squid, and other marine reptiles. Plesiosaurs were also known to scavenge on dead animals.
Predators
Plesiosaurs were preyed upon by other marine reptiles, such as mosasaurs and giant sharks. They were also hunted by land predators, such as dinosaurs.
Extinction
Plesiosaurs became extinct at the end of the Cretaceous Period, about 66 million years ago. The extinction event that caused their demise also caused the extinction of the dinosaurs and many other marine creatures.
Plesiosaur Fossils
Plesiosaur fossils have been found all over the world. Some of the most well-known plesiosaur fossils include the _Tylosaurus_ from North America, the _Elasmosaurus_ from South America, and the _Plesiosaurus_ from Europe.