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. The reason for this is not known.