Warm-blooded vertebrate metabolisms are endothermic . They generate most, or all, of their body heat internally. Endotherms characteristically have high rates of heat production. Cold-blooded vertebrate metabolisms are ectothermic . They receive most, or all, of their body heat from an external source, usually directly from the sun.
Ectotherms typically have a slower metabolism.
Many of these lines of evidence are consistent with endothermy in at least some theropods and ornithopods , but most evidence does not support endothermy in the other dinosaurs. The evidence does not support extreme views of dinosaur metabolism, in other words, that all were ectothermic, or all were endothermic. The evidence suggests a probable variety of metabolisms in dinosaurs, including endotherms and ectotherms, some of which were also heterotherms and gigantotherms. Not all dinosaurs were completely upright. Speed, Activity Levels and Agility Speed, sustained activity, and agility in some dinosaurs is evident in their skeletal structures, brain size and brain complexity, and in the speeds estimated from dinosaur trackways.