Whilst dinosaurs were walking the land, ichthyosaurs (meaning fish-lizard) were swimming in the sea. They are marine reptiles that evolved streamlined, fish-like bodies for fast swimming.  Ichthyosaurs lived in waters that covered much of continental Europe during the early Jurassic Period, around 150 million years ago. They lived in both shallow and deep waters and possessed long thin jaws with numerous teeth for preying on a range animals, for example octopus, squid and cuttlefish.