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LET'S EXPLORE Prehistoric life

When did reptiles rule the seas?

Marine reptiles of the Jurassic PeriodMarine reptiles of the Jurassic PeriodDuring the Age of Dinosaurs, reptiles were also masters of the oceans. Most were hunters. They chased prey such as fish, squid and shellfish. Ichthyosaurs looked like dolphins, while plesiosaurs, with their small heads and long necks, resembled dinosaurs. Both types of marine reptile had to stay near the surface and poke their heads out now and again to breathe air.

Temnodontosaurus, a giant ichthyosaurTemnodontosaurus, a giant ichthyosaur


Like modern dolphins, ichthyosaurs (ICK-thee-oh-SAWZ) had long flippers for steering, and strong tails to propel them through the water. They had big eyes to spot their prey. Some ichthyosaurs were enormous, growing up to 15 metres (49 feet) long. They spent their whole lives at sea, and gave birth to live young.


The ichthyosaur Temnodontosaurus had the biggest eyes of any vertebrate animal that has ever lived. Each eye measured about 26 cm (10 inches) across.

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