"In my view, homosexuality is a choise and can only be made from an intelligent being"
Studies on many animals have shown homosexual behavior in animals is not a choice and certainly in mammals (sheep, see refs.) seems to be related to structural changes in the brain caused by environmental factors such as exposure to hormones in the womb. This would explain why it is still common despite being a trait that is unlikely to be passed on.
a comprehensive survey of homosexuality in animals can be found in: Biological Exuberance : Animal Homosexuality and Natural Diversity.
Bruce Bagemihl. St. Martin's Press; ISBN: 031225377X
this is a good review of homosexuality in sheep: "Review: brain aromatization and other factors affecting male reproductive behavior with emphasis on the sexual orientation of rams. K.L. Pinckarda, J. Stellflugb, J.A. Reskoc, C.E. Rosellic, F. Stormshaka. Domestic Animal Endocrinology 18 (2000) 83—96"
"Hormone Behavior 1995 Mar;29(1):31-41 A comparison of LH secretion and brain estradiol receptors in heterosexual and homosexual rams and female sheep.Perkins A, Fitzgerald JA, Moss GE."
"Journal of Animal Science 1992 Jun;70(6):1787-94 Luteinizing hormone, testosterone, and behavioral response of male-oriented rams to estrous ewes and rams. Perkins A, Fitzgerald JA."
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