actually there is some evidence incest is beneficial in small, cut-off groups of species where increased genetic mutations can be of great benefit - also where incest is more likely to occur. Polygamy is something brought about by ugly people. Cannibalism may be justified in times of crisis. But I don't think you should be speaking on this stuff when you sound so confused. It makes the religious nuts think the whole argument sucks, because you can't articulate your ideas.