Palaeobiologist Dr Susana Gutarra taking measurements from a very complete specimen of Liopleurodon, a plesiosaur from the Middle-Late Jurassic of Germany (Museum of Palaeontology in Tübingen).

Sea-going reptiles from the Mesozoic era evolved a great diversity of body forms and sizes. Changes in their body and limb anatomy throughout evolution are associated with swimming adaptations. The variety of locomotory modes in Mesozoic marine reptiles is illustrated by (bottom-to-top) an early mosasauroid, a placodont, a plesiosaur and a fish-shaped ichthyosaur.