In the Cretaceous seas, the success of bony fish led to the development of predatory reptiles. One fine example of the strangeness of evolution is the Elasmosaurus, a kind of plesiosaur. This 12-metre giant had an exceptionally flexible neck twice as long as its body. The creature could move in every direction and surprise its prey by thrusting its tiny head like a harpoon. It had to be on the watch for attacks by pliosaurs (a reptile with a short neck and a massive head) and by mosasaurs (newcomers in the history of evolution). These large snake-like lizards were at the top of the food chain. Other species, such as dolphin-like ichthyosaurs and geosaurs, became extinct before the end of the Cretaceous period.
Canadian Heritage Information Network
Canadian Heritage Information Network, Canadian Museum of Nature, Musée du Séminaire de Sherbrooke, Royal Tyrrell Museum

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