Originally Posted by Sly

How exactly do you think we, as humans, have gained the knowledge that we now have about the human body and also the animal kingdom? Do you think scientists just randomly came up with theories and tested them only when absolutely necessary (i.e. when someone is about to die?)

Insulin is a pretty good example. For many years it came from pig livers. The pig would need to die in order to extract the insulin. Today most of it seems to come from plants. How many diabetics do you know?