However, more recent research suggests that dinosaurs were endothermic, having the ability to warm themselves with their metabolism, which made them less reliant on the sun.
So even though most animals today are either one or the other, dinosaurs were probably somewhere in between – some dinosaurs were more ectothermic, while others were more endothermic.
When we look through a thin section of dinosaur bone, the pattern of these osteons looks more like that found in endothermic animals rather than that found in ectothermic animals.
Of course, there is still a lot of variation in these patterns, but in general, the bone structure of dinosaurs implies that they were more likely to be endothermic, like birds and mammals.
It gets a bit complicated up in here, but basically the thing to keep in mind is that endothermic reactions, which consume heat, are favored if heat is added so higher temperatures tend to feed endothermic reactions.