What do you think "homosexual advocates" are claiming? All I personally am claiming is that animals have been observed to engage in sexual activity with members of the same sex. Again, I don't make any claims about what that should mean for human society.
As to your focus on orifices and [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse], are you suggesting that if a male doesn't [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse], he hasn't been engaging in sexual activity? Is [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse] and an orifice what defines sexual behavior? What about for females? Females, obviously, don't [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse]. And do you think a female has not been engaging in same sex activity if no orifices are penetrated? In any case, you are incorrect in your assumption that [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse] has never been observed during same-sex sexual activity among animals. Domestic rams (i.e., male sheep) have been observed mounting each other, achieving anal penetration, and [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse]:
Same-sex sexual partner preference in hormonally and neurologically unmanipulated animals, by Paul L. Vasey. See also the Perkins & Fitzgerald, 1992, test upon which this quote was based:
Ram mating behavior after long-term selection for reproductive rate in Rambouillet ewes, J.NJ. N. Stellflug, and J.G. Berardinelli, [size=-1]
J. Anim. Sci. 2002. 80:2588-2593.
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