First, this is a museum trying to generate interest in their display. Reading over the article it makes some powerful claims, such as "homosexuality is common".
It seems to me the entire display is based on much speculation.
From the article:
"The most well-known homosexual animal is the dwarf chimpanzee, one of humanity's closes relatives. The entire species is bisexual."
See the conflict in the above? Bonobo's (dwarf chimps) are bi-sexual, not homosexual.
Quote from article:
"Indeed, there is a number of animals in which homosexual behaviour has
never been observed, such as many insects, passerine birds and small mammals."
Followed by:
"To turn the approach on its head:
No species has been found in which homosexual behaviour has not been shown to exist, with the exception of species that never have sex at all, such as sea urchins and aphis."
I am always hesitant to assign as true an article which has so many conflicts within its context. The entire article is riddled with unquantified terms such as "common" mostly coming from this man - Petter Boeckman (for this article).
No species has been found in which homosexual behaviour has not been shown to exist, with the exception of species that never have sex at all, such as sea urchins and aphis. Moreover, a part of the animal kingdom is hermaphroditic, truly bisexual. For them, homosexuality is not an issue.[18]
http://en.wikipedia.org/wiki/Homosexual_behavior_in_animals
The above is speculation, not fact. You forgot the leading sentence in the wiki linked article:
'While studies have demonstrated homosexual behavior in a number of species, Petter Bøckman, the scientific advisor of the exhibition Against Nature?
speculates that the true extent of the phenomenon may be much larger than currently recognized:"
So petter Bockman speculates "no specie has been found". Very different context.
I did a search on Petter Bockman. He has no scholarly articles, he has no published papers, he has little history other than this one museum display.
But, sex sells.
Granted bisexual may be a better term term, but bisexual does include homosexual sex...
In humans, few are homosexual, some are bi-sexual, most are heterosexual. I know several people who experimented with same sex partnering in their youth, who would not participate in those encounters now. Simply put, they have no desire. Body changes, ie hormones most likely. Developmental sexual variable.
The claims are 'homosexual'. From people trying to present themselves as scientists. And that bothers me. Another name that keeps coming up in all the searches is Bagemihl. So I did a search on him.
"Bagemihl's ideas have caused a stir in the higher, human community, especially among scientists who find it simplistic to equate any animal behavior with human behavior."
"Sexuality helps animals maneuver around each other before making real contact," says Martin Daly, an evolutionary psychologist at McMaster University in Ontario. "Putting all that into a homosexual category seems simplistic."
"Animal sexuality is more complex than we imagined," says Bagemihl.
Keeping in mind, Sex Sells:
http://www.time.com/time/magazine/article/0,9171,990813-1,00.html
If its more complex, why is he (bagemihl) so determined to fit all of it into homosexual? Where is asexual? Where is autoerotic? Where is homosocial in all his 'research'?
Heres an article I havent had time to pick apart and translate yet. Its on various bird species.
http://beheco.oxfordjournals.org/cgi/reprint/18/1/21.pdf
A snippet from above:
"A pattern has been observed in many representatives of Laridae (Gulls) in which supernormal clutches (associated with FF pairing, courtship, mounting, and coparenting) are more frequent when the population exhibits a female-biased sex ratio (Hatch 1993; Bagemihl 1999; Nisbet and Hatch 1999).
These studies experimentally manipulated the sex ratio to produce a female bias by removing males. The frequency of supernormal clutches of 4–6 eggs (a measure or index of FF pairings) was greater in colonies from which males had been removed than it was in control colonies (Conover and Hunt 1984). It may be advantageous for females to pair with other females and coparent while seeking extrapair reproductive opportunity with paired males (to obtain fertilized eggs). Mills (1991) found that although FF pairs in silver gulls, L. novaehollandiae, have a lower overall lifetime reproductive success thanMF pairs (0.85 FF vs. 1.91 MF, mean number of offspring fledged in lifetime), over 50% of females in populations do not breed at all."
