u actually cannot prove this - furthermore logically this is not a practice that could have survvied or else u and i would not be here...
i can prove, or rather you can google, that the greeks not only practiced homosexuality but encouraged it in certain situations - especially the army where fighting alongside your partner was seen as an advantage...
have a look at some of the paintings in pompeii too...
to someone killing animals is bad to someone it is sport..
absolutely... and as you metion, for some, having sex with small children is the norm... for others its the most henious crime... so do we lock these people in prison and chop of their ganglies as society expects now... or do we say that actually we might all be better off if we accepted them as different and treat them as such...?
then u actually start believing them as normal..
quite right... but lets not get caught up in a world of persecution and hatred for anything that doesnt fit into our idea of normal - being different doesnt make you evil...
it is pleasureable now only becasue u r reducing the chances of procreation by unnatural methods
not quite sure what your point is here - sex has always been pleasurable but hasnt always been for procreation... for both people and animals...