even more simply stated; if a creature does not reproduce, he is a biological failure. so in that sense, yes, homosexuality is a genetic deffect. it is observed in nature that the main goal in each organism is to survive and reproduce. even if an animal expresses homosexuality, they are still attempting to preform the very acts that are supposed to lead to reproduction. "love" is not a factor in the animal world (and if someone wants to argue that, that's for another time in another topic) so a reasonable deduction would be that the animal is confused. and yes, the confusion can come from abnormal amounts of hormones of the opposite gender. these are chemical deffects and are the same deffects found in humans.