« Xuanhuasaurus | Home | Yangchuanosaurus »
Yandusaurus
Yandusaurus (pronounced YAN-doo-SAWR-us), the name means “Yandu reptile,” was a member of the hypsilophodontid dinosaur genus and the earliest known example of such dinosaurs. This fact makes Yandusaurus an important evolutionary piece of this particular genus of dinosaurs. Yandusaurus flourished approximately 163 to 165 million years ago during the Bathonian age of the Middle Jurassic in what is now modern day China. All other examples of hypsilophodontid are from the Late Jurassic to Late Cretaceous periods.
Yandusaurus was a small animal that only stood about a third of a meter (one foot) high. It was at least three times as long as it was high and weighed about 7 kg (15 Ib). Yandusaurus had a head with a short snout and had a wide, high skull that featured sockets what would have allow it to have large eyes. These large eye sockets imply that Yandusaurus had excellent eyesight. It had a somewhat thin body and a long neck. Also, Yandusaurus had a long tail that scientists believe the dinosaur used to balance itself while it ran due to the animal’s similarity to other species that used their tail in this fashion, in fact all other ornithopods do so, but due to only have one fossil example of the animal with the base of its tail still intact this remains purely conjecture.
Yandusaurus propelled itself with a pair of long, athletic hind limbs, which were built for quick running with clawed feet. These legs would have allowed it to escape from predators like Szechuanosaurus and Yangchuanosaurus. Its front limps were also relatively large and featured clawed hands. No one is certain whether or not Yandasarus was able to grasp anything with its hands.
Paleontologists believe that Yandusaurus was primarily a plant-eater due to the structure of its teeth and jaw. Its teeth were triangular shaped with surface ridges that are similar to many other plant eating dinosaurs; however, it is possible that Yandusaurus may have eaten some types of insects as well.
Yandusaurus fossils were first uncovered in 1978 in the Sichuan Province in the People’s Republic of China.
1. 1978
2. 7 kg or 15 Ib
3. China
4. Herbivore
5. 0.3 meters or 1 foot
6. 1-1.5 meters or 3-5 feet