Hypsylofon was a small dinosaur, reaching 2 meters in length. It was a peaceful herbivore with a head no larger than a child’s head. Hypsilophodon’s jaws contained a row of curved teeth with jagged edges that cut through foliage and other parts of plants beautifully. At the end of the snout of Hypsilophodon, there was a keratinized beak, like that of turtles, with which he pinched off the leaves of plants.
Dinosaur cheeks are rare, but Hypsilophodon had them and could stretch, which helped keep food in the mouth when chewing. Large openings at the back of the skull served as attachment sites for powerful jaw muscles.
Hypsilophodon limb bones were long, thin and light. Its hind legs had powerful muscles that allowed it to run fast and dodge predators. Probably, the hind legs of Hypsilophodon were similar to the legs of modern flightless birds, such as the African ostrich and the Austrian emu. The dinosaur’s body was tilted to the ground and balanced very well, which allowed him to abruptly change direction, running away from enemies. Maneuvering was aided by a long hard tail that acted like a rudder.
All these traits indicate that Hypsilophodon was an excellent runner. Apparently, his way of life resembled that of modern African antelopes, which feed on tender leaves and branches and flee from enemies by running fast.
When scientists first studied the limb bones of Hypsilophodon, they were surprised by their resemblance to the bones of monkeys and some other animals that climb trees. Therefore, in the first reconstructions, hypsilophodon was often depicted on tree branches. Today it is clear that this assumption is false. Dinosaur’s fingers did not allow him to wrap around branches, so he could not climb a tree.