Plesiosaurs swam like penguins

New simulations might resolve a long-standing debate

plesiosaur

FLIP FLAP  New simulations could end years of debate on plesiosaur motoring. The ancient marine reptiles, one illustrated here, most likely swam using their front flippers for power and their back flippers for steering.

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Fossil hunter Mary Anning’s 1823 discovery of the first complete plesiosaur skeleton led to more than 190 years of arguing.