cpurser, I would wonder how these pscyhologists woudl explain animal homosexuality. Especially among chimpanzees (bonobos specifically) there are a high amount of homosexual and bisexual relationships.
Anyway I think the deal should be eiether to get equalize all the benifits that married people have among everyone else, (like Sweden has done) or to start allowing people to do anythign they wnat that is among "consentiual adults" This woudl include polgymy and polygany. The nations seems to be heading down this path anyway. Just look at the recent rulings strking down the sodomy laws. Pretty soon there will be a court case to the supreme court regarding a gay couple that wasn't able to get the same benifits as a married couple. It'll be interesting to see what happens then. It seems that quite a few courts are already siding with gay couples.
