Knowledge in the medical area is something that is always going to be needed and as times goes by the amount of knowledge is always going to have to keep increasing and increasing. New treatments and medicines can be created but the question will always be whether or not they are actually effective. Now, even if it is ethical or not testing could always be done animals. But as much testing done on animals their reactions to the experiments are definitely not always going to be the same as they are for humans. In the end, the need for knowledge I believe is the greatest root cause because it is what drives the exploitation to be done regardless of everything else, it’s only the results that seem to be what matter.