How Plesiosaurs Ruled the Ocean using their Flippers —

Plesiosaurs ruled the oceans during the time of the dinosaurs with specially adapted flippers that enabled them to swim faster and with greater efficiency than any other animal. Luke Muscutt studied the 4-flipper arrangement by conducting experiments at the University of Southampton to investigate exactly how it all worked...

https://www.youtube.com/watch?v=chfG229nLZI