Biological cause eh? That makes perfect evolutionary sense. Please. If that were even remotely true then all homosexuals would be gone in 1 generation (because they wouldn't procreate <----Notice proevolve).
This is an example of the logical fallacy of "appeal to ignorance" (If I can't explain it, it could not happen).
(1) How do you explain homosexuality in animals if there is no biological cause?
http://www.bidstrup.com/sodomy.htm
(2) Some gays do in fact reproduce even though most of their sexual partners may be the same gender. All it takes is one opposite gender partner to reproduce.
(3) Recessive traits can be quite deliterious (killing homozygous individuals before they can reproduce - hemophilia, cystic fibrosis, sickle cell anemia) but still be carried in the population because the heterozygous individual has some advantage (sickle cell confers malaria resistance).
(4) There are natural selection arguments for why a gay gene might be advantageous in a population. If one of my offspring is gay it might make it more likely that my grandchildren will survive and reproduce. Say I have two children, one gay and the other straight. The straight one reproduces. The gay one, although not able to reproduce, still has maternal/paternal feelings for his nephews/nieces. This gives the nephews and nieces (my grandchildren) an advantage, since they effectively have three parents (or even four if there is a gay partner). If the gay gene were recessive (likely), it is quite possible that it could be carried along in the population and only individuals homozygous for the trait would be gay.
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