Camptosaurus

Camptosaurus was a widespread, medium-sized ornithopod that lived across western North America during the Late Jurassic epoch. Numerous well-preserved skeletons have been recovered from the famous Morrison Formation, making it one of the best-understood Jurassic ornithopods. Measuring between five and seven metres in length, Camptosaurus possessed heavily built hindlimbs and broad, weight-bearing feet. It likely browsed on low vegetation on all fours, but had the agility to run on two legs when fleeing predators like Allosaurus. Its hands ended in small, rounded hooves on the inner digits, foreshadowing the large thumb spikes of later Cretaceous iguanodontians. With packed, serrated teeth, it efficiently masticated ferns, cycads, and horsetails along lush river systems.

It represents an early evolutionary stage of iguanodontians before the development of large, conical thumb spikes.

Where and when

Camptosaurus lived in the Late Jurassic, from 155 to 148 million years ago (Kimmeridgian-Tithonian age). Its remains come from United States, in the Morrison Formation.

The numbers

Length 6 m (estimates run from 5 to 7 m). Mass about 980 kg. Hip height about 1.8 m. That is 3.5 human-lengths, or 0.54 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

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