Hypsilophodon (Cretaceous)

Hypsilophodon ("high-ridged tooth" in Latin) is a small Cretaceous period herbivorous dinosaur lived about 125 million years ago. First recovery was made in 1849 on the Isle of Wight in England by construction workers. First, the skeletal structure was incorrectly thought to belong to an arboreal creature. However, paleonthologist Peter Galton amended the misinterpretation after bone structure modeling and turning the claws into the right direction.
Being almost 2 metres high and weighing only 20 kilograms, Hypsilophodon was very nimble and fast, hiding from predators in the coarse grass. Low posture helped to provide a perfect balance. The reptile limbs were thin, light and lengthy with powerful hind limb muscles similar to a living ostrich.
The reptile also had remarkably sharp vision because of the scleral ring of small bone plates around the eye sockets. The beak was sharply pointed and the jaws effectively shredded foliage, mashing it easier to digest. When threatened , the dinosaur used a stiff elongated tail for defense. It struck the attacker or tried to gain some time for escape.