Plesiosaur

Paleo Hall at HMNS plesiosaur

Stukely plesiosaur

Conybeare Plesiosaur 1824

Mary Anning Plesiosaurus

Great Sea-Dragons

Cope Elasmosaurus

Plesiosaurs were a group of large, marine reptiles that lived during the Mesozoic Era, particularly known for their presence in the Jurassic Period and Cretaceous Period. Characterized by their long necks, small heads, and flippers, plesiosaurs are often depicted in popular culture and are one of the most recognizable types of prehistoric marine life.

Description

Plesiosaurs had a unique body structure among marine reptiles. Their most distinctive feature was their long necks, which were made up of a large number of vertebrae. This adaptation allowed them to have a wide range of motion in the water, which was likely beneficial for catching prey. Their bodies were broad and flat, with a short tail, and they possessed four large, paddle-like flippers that enabled them to move through the water with a flying motion, similar to the movement of sea turtles.

Classification

Plesiosaurs are divided into two main families: the Plesiosauridae, which had long necks and small heads, and the Pliosauridae, which had shorter necks and large heads with powerful jaws. This classification is based on their physical characteristics and adaptations, which suggest different hunting strategies and dietary preferences.

Diet and Behavior

The diet of plesiosaurs likely consisted of fish, cephalopods such as ammonites and belemnites, and other small marine animals. The long-necked varieties might have used their necks to reach into schools of fish or to snatch prey from the sea floor, while the short-necked varieties were probably powerful swimmers that could catch larger prey, using their strong jaws to bite and tear.

Fossil Record

Fossils of plesiosaurs have been found in various parts of the world, indicating that they were widespread across the oceans during the Mesozoic Era. These fossils include not only bones but also impressions of soft tissues, such as the flippers, which provide valuable information about their anatomy and how they might have moved in the water.

Extinction

Plesiosaurs, along with many other marine reptiles, went extinct at the end of the Cretaceous Period, around 66 million years ago. This extinction event, which also saw the demise of the dinosaurs and many other life forms, is believed to have been caused by a combination of catastrophic events, including volcanic eruptions, climate change, and the impact of a large asteroid or comet on Earth.

In Popular Culture

Plesiosaurs have captured the public's imagination and have appeared in various forms of media, from books and films to television shows. They are often associated with the legend of the Loch Ness Monster, a mythical creature said to inhabit Loch Ness in Scotland. Despite numerous sightings and theories, there is no scientific evidence to support the existence of such a creature in modern times.