OK, so we've determined that having gay relations is unnatural. Now the question becomes, how unnatural is Marriage. How often does it happen in nature that two animals make a long term commitment to each other.
See, my reason for being undecided on the whole gay marriage debate is that even if having your shit pushed in is unnatural, having a piece of paper saying you belong me is just as unnatural.
P.S. just on the topic of threesomes. I bet @
Grunta; and @
Nikko; never resorted to having a threesome.