Reptiles require a good body temperature, because their blood is highly influenced by the environment's own temperature. That's why people talk about cold blood on reptiles. They rely on a certain temperature to warm their own body, and it certainly becomes indispensible to them, because slight changes affect their whole body. This is not a very complete explanation, but, in the end, keep that in mind. I just hope I could help :)
indigenous species are native species of a country and bred in the same country by similar species. Exotic species are species that are brought from other countries bred within same varieties or crossed with indigenous or other exotic species.
