Quote Originally Posted by Wolfx View Post
Why? please do tell.
Disease. Different diseases live in different areas. A species from one area will not have evolved an efficient immune response to a disease that normally lives in another. So if you expose them to that disease, it could easily kill them. So, a disease that will not hurt a chameleon, or a frog from madagascar, may well kill a frog from central america. This is why Chytrid Fungus is so nasty. Huge swaths of the Americas and Australasia have frogs with little to no natural resistance. Chytrid is to non-african frogs what smallpox was to native americans.