Homeostasis is the regulation of conditions in the body, such as temperature. Different animals function best at different body temperatures. Warm-blooded animals, such as mammals and birds tend to have higher optimum body temperatures than cold-blooded animals, like reptiles. However, scientists cannot fully agree on whether dinosaurs, which are classed as reptiles, were warm-blooded, cold-blooded or even somewhere in- between!

Reptiles depend on the environment to control their body temperature, whereas warm-blooded animals can regulate their own body temperature. In order to do this they need to eat as much as ten times more food than a cold-blooded animal. Hence it is more likely that giant herbivores could not have eaten enough to be warm-blooded. Scientists also found that in general warm-blooded mammals grow about 10 times faster. Research indicates that dinosaur growth does not resemble reptiles or warm-bloods, but falls somewhere in-between.

All this indicates that  dinosaurs could move, grow and reproduce much more quickly than reptiles. It also would have made them dangerous predators. At the same time, their lower metabolic rate allowed them to survive on less food. That explains why they were so big!!  Imagine how much food a tiger would need to eat if it was the size of a T.Rex!

To help you understand how we manage not to overheat in the hot weather, or freeze in the winter, have a look at Part 1 of our  “How to” revision guide on Homeostasis. This guide explains the basics of homeostasis, and what we need to keep the same in the human body. This guide concentrates on thermoregulation: