Bactrosaurus

Bactrosaurus was a hadrosaur from the Upper Cretaceous about 70 milion years ago. This plant-eating dinosaur. was found in  the Gobi Desert of China. It was about 6 metres (20 feet) long and 2 metres (6.6 feet) high when standing on all fours. It weighed 1.1 to 1.5 tonnes (2,400 to 3,300 pounds).

Research showed that this genus and its near relatives were unusually prone to cancer. Among more than 10,000 specimens x-rayed, tumors were only found in these Cretaceous hadrosaurs (duck-billed dinosaurs).Rothschild B.M. et al 2003. Epidemiologic study of tumors in dinosaurs". Naturwissenschaften 90 (11): 495–500.  The reason for this is not known.

 References 

Category:Dinosaurs of Asia
Category:Cretaceous dinosaurs
Category:Hadrosauridae