Which way does your monkey swing?

For animals, being gay is as natural as the birds and the bees, says biologist Bruce Bagemihl. He tells Tim Cornwell how scientists have both suppressed and oppressed homosexual animals

If only they could talk. But it might have come as a shock to Hugh Lofting's fictional Dr Dolittle, the mild-mannered animal doctor who learns to converse with his pets and patients, to discover their sexual proclivities. Imagine Jip the dog explaining to his stunned owner, in nose twitches and tail wags, that he's in love with another dog. Or the pushmi-pullyu, that two-headed denizen of the African jungles, shyly confessing that he is "bi". ("Lord save us," cried Dab-Dab the duck, "How does it make up its mind?") There is no reference to Dr Dolittle in Biological Exuberance, American biologist Bruce Bagemihl's exhaustive survey of homosexuality in animals - though Oscar Wilde, the orca and the orang-utan do all get a mention. But Bagemihl's work is tinged with comedy as he describes how biologists and zoologists have for years stifled or skirted the fact the animals under their observation are up to all sorts of naughtiness - oral, anal, masturbatory, hetero, homo and bisexual. Biologist Valerius Geist, for example, after watching the repeated male-to-male mountings of bighorn rams, struggled "to conceive of these magnificent beasts as 'queers'. Eventually I called the spade a spade and admitted that rams lived in essentially a homosexual society."

As Bagemihl sets out to redress the balance, he strays into humour, intentionally or not. After noting homosexual mounting and same-sex pair bonding among pedigree dogs such as beagles, basenjis and Weimaraners, he says: "Homosexuality has also been verified in other animals kept as pets, including same-sex courtship and mounting in guinea pigs; homosexual mounting in female domesticated rabbits and hamsters; and same-sex pair-bonding, courtship and mounting among caged birds such as zebra finches, Bengalese finches and budgerigars. Many common aquarium fish also exhibit homosexuality or transsexuality."

Is your goldfish gay? A serious question, actually. Bagemihl does not tackle Darwinism head-on, but he argues that the single-minded focus among academic biologists on reproduction and natural selection has closed scientists' eyes to any explanation of animal sexual behaviour other than that of mating with the opposite sex. He calls for "a larger vision or a way of looking at the natural world that includes reproductive and non-reproductive activity". We accept the homosexual identity in humans, this logic goes, and it's time to redress the balance in the animal world.

Biological Exuberance is Bagemihl's ten-year quest to subvert "homophobic" science by re-reading field studies of animal behaviour. Homosexual walruses and lesbian flamingos (with suitable cautions about the employment of such human labels) abound in a work that amply illustrates its premise that the natural world is "teeming with homosexual, bisexual and transgendered creatures of every stripe and feather". He documents same-sex pairings in more than 450 species.

For two centuries, Bagemihl argues, field observations of "the love that dare not bark its name" have been dismissed as irrelevant, perverse or just plain "bestial". But while Bagemihl himself is openly gay, his book is more than a polemic of sexual politics or a queering of zoology. It includes a 400-page index to homosexuality in animals from antbird to zebra, from the savanna baboon to the great cormorant, all drawn from published studies. It is littered with distracting photographs of happy couplings between male giraffes or female pygmy chimps, not to mention line drawings of hedgehog cunnilingus.

Bagemihl's personal favourite is the cheetah. As children we learned it was the fastest thing on four legs. No one taught us, however, that roughly a third of male cheetahs live in same sex pair-bonds. Heterosexual pair-bonding does not take place, Bagemihl says, although obviously mating occurs. Instead, "two or three males will pair off with each other and become constant companions, spending all their time together, defending each other, hunting together, and in some cases this is accompanied by sexual behaviour such as mounting".

Other examples include the red-billed black swan of Australia, Tasmania and New Zealand. Homosexual pairs engage in "greeting ceremonies", raising their wings and honking; they engage in parenting as a same-sex couple, either chasing away the previously mated female or forcibly adopting someone else's eggs. Because two males command the largest territories and the best nesting sites, "homosexual pairs are often more successful than heterosexual ones at raising chicks I 80 per cent of homosexual parenting efforts are successful, compared to only about 30 per cent of heterosexual ones".

Bagemihl, formerly on the faculty of the University of British Columbia, now lives in Seattle, Washington, in the United States. As an undergraduate biology student, researching animal homosexuality, he discovered there was no textbook offering an overview of the topic and decided to write one. "No introductory biology text, virtually no zoology texts discuss homosexual behaviour in animals at any length," he explains. "Even within university-level courses, there's a huge silence around this topic." Even when a cursory discussion takes place, it "happens in ways that tend to trivialise it or minimise it. Usually it isn't talked about at all."

Homosexual behaviour in animals is regarded as a type of pathology, social or physiological, attributed to an absence of the opposite sex or to the unavailability of heterosexual partners, Bagemihl complains. While often observed, it is explained away as a form of dominance behaviour, aggression or simply a mistake, that animals that engage in homosexual behaviour cannot distinguish their partner's sex. Other interpretations are that it is an imitation of sexuality, of animals imitating the opposite sex.

The weakness of the book in American reviewers' eyes has been that while Bagemihl calls for a "larger approach" to animal behaviour than a single-minded focus on reproduction, he struggles to offer the woolly "biological exuberance" of the title as an alternative. "I'm not questioning that a large amount of animal behaviour is geared towards reproduction, that is undeniable. I'm not questioning all the implications of that, natural selection and evolution and so on," he says. "That's a very useful approach to looking at animals and their behaviours and social contexts. But I think there is a large amount of animal behaviour and types of behaviour that falls outside the domain of reproduction, and these types of behaviour have been a longstanding puzzle for biologists."

What Bagemihl says he is not doing is arguing that the presence of homosexuality in animals makes it "natural" in humans. At times the charge of "unnaturalness" - the claim that homosexuality did not occur in "nature", ie between animals - was used to justify the social suppression of homosexuality. But in ancient Greece, same-sex love was elevated as purer than base "animal-like" passions. The Nazis, though, labelled gay men used in experiments as "test animals". Homosexuality, he posits, is as "natural" as heterosexuality.

"I am gay, but I didn't undertake the study because of that, in order to try to prove anything about the naturalness of sexuality," he says. "A lot of the book is being interpreted as an apology for homosexuality in people, and that is not what I'm doing at all. We can't jump to any conclusions about people from what animals do."

Instead Bagemihl is more or less taking the recent revolution in attitudes to human sexuality into the "natural" world. Words such as "deviant" or "perverse" should be zoologically, as well as politically, incorrect, he suggests. Animals ought to be allowed to be themselves. "Traditionally anything that fell outside reproduction was seen as anomalous," he says. "There's a complexity there that we may not yet understand."

Biological Exuberance is published this month by Profile Books, Pounds 25.00.

EXCERPTS FROM BIOLOGICAL EXUBERANCE

In several studies of captive animals, same-sex partners in rhesus macaques, bottlenose dolphins, cheetahs, long-eared hedgehogs and black-headed gulls were forcibly separated - because their activities were considered "unhealthy" or to study their reaction and behaviour on being reunited or to try to coerce the animals to mate heterosexually.

A female pair of orange-fronted parakeets was forcibly removed from its nest to "allow" an opposite-sex pair to breed in its stead (based in part on the mistaken assumption that female pairs are unable to be parents).

Female stumptail macaques had electrodes implanted in their uteri to monitor their orgasmic responses during homosexual encounters, while female squirrel monkeys were deafened to monitor the effect on vocalisations made during homosexual activities.

Although intended ostensibly to reveal important behavioural and developmental effects, these "treatments" applied to animals have in some cases been disturbingly similar to those administered to people to try to "cure" them of homosexual behaviour (separation or removal of partners, hormone therapy, castration, lobotomy and electroshock).

n The history of ideas about and attitudes towards homosexuality is encapsulated in the titles of zoological articles (or book chapters) on the subject through the ages: "Sexual perversion in male beetles" (1896); "Disturbances of the sexual sense (in baboons)" (1922); "Pseudomale behaviour in a female bengalee (a domesticated finch)" (1957); "Aberrant sexual behaviour in the South African ostrich" (1972); "Abnormal sexual behaviour of confined female hemichienus auritus syriacus (long-eared hedgehogs)" (1981); "Pseudocopulation in nature in a unisexual whiptail lizard" (1991). The prize, though, surely has to go to W. J. Tennent, who in 1987 published an article titled "A note on the apparent lowering of moral standards in the lepidoptera".

* Even in captivity, the sex of animals is often mistaken, and the consequent "amending" of mating or courtship activity from heterosexual to homosexual sometimes results in elaborate retractions, revisions and reinterpretations.

Perhaps the most convoluted mix-up of this sort involves a set of king penguins that was studied at the Edinburgh Zoo from 1915-30. The various permutations and shufflings of mistaken gender identities (on the part of human observers, not the birds) reached Shakespearean complexity. Originally the the penguins's sex was determined on the basis of what was thought to be heterosexual behaviour, and the birds were given (human) names accordinglyI Subsequent re-pairings and breeding activity eventually revealed that the sex of all but one of the birds had been misidentified I "Andrew" was renamed Ann, "Bertha" turned into Bertrand, "Caroline" became Charles and "Eric" metamorphosed into Erica I Two penguins that had initially been seen engaging in "heterosexual" activity later turned out to be same-sexed, while premature observations of lesbian mating between Bertha and Caroline were confirmed as homosexual - but actually involved the males Bertrand and Charles.