The Hydrodynamics of Plesiosaurs

Millions of years ago when the dinosaurs were walking around on the earth, there was a type of marine reptile called a plesiosaur that was swimming in the seas. Plesiosaurs were reptiles that had evolved to live in the ocean, and had four big flippers that they used to swim with. These flippers were similar to the flippers of a turtle or sea lion, but whereas these creatures only really use their front two for propulsion, plesiosaurs used all four.

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