As dinosaurs grew into the behemoths of the Cretaceous period they evolved many extraordinary but apparently useless features including spikes, sails horns, crests and the tiny arms of tyrannosaurs. The program reviews these unusual features and discusses theories of why they exist.
DOCUycc46fl，化石模型非常不错，电脑特效差强人意，科学论断挺有意思尤其是关于霸王龙小短手那部分的阐述！
