Biology of Homosexuality – The Animal Farm : A Queer Perspective


Gay animals

-Agnivo Niyogi

“The universe is not only queerer than we suppose, but queerer than we can suppose.”
-J.B.S. Haldane, evolutionary biologist

I think nothing needs to be added after this quote by the great Biologist. Although he might not have hinted at “queerness” as in homosexuality but nevertheless his words reflect the order in nature.

Nature has never differentiated between her creations. Homosexual behaviour coexisted with heterosexuality since the days of primordial soup. Instances of same-sex relationships in animal kingdom could blow any “doubting dimwit” off his wits. A 1999 review by researcher Bruce Bagemihl shows that homosexual behaviour has been observed in close to 1500 species, ranging from primates to gut worms, and is well documented for 500 of them. “The animal kingdom [does] it with much greater sexual diversity — including homosexual, bisexual and non reproductive sex — than the scientific community and society at large have previously been willing to accept,”  writes Bagemihl, in his review. In a special issue of Live Science, Sara Goudarzi spoke about a museum opened in Norway in 2006 to show case prevalence of homosexuality in at least 51 animal species.

The terms gay or lesbian do not apply to animals. Those are more of human make. Homosexual is best suited to animals. Scientists working on animal behaviour, despite many challenges, have shown that same-sex relationship has been observed sporadically in almost all animal species and there are few cases where animal groups participate in it exclusively. It is imperative here that I mention a tribe of apes who engage exclusively in same sex mating and are the largest known population of animals who indulge in homosexuality. The Bonobo-a society of apes- engage in heterosexual as well as homosexual behaviour. Female homosexual behaviour is more noted in them. 60% of sexual behaviour in this tribe is between men-men or female-female.

In its issue, even the New York Times reported the presence of homosexuality among animals and raised the question of its prevalence in other groups of animals. Biologists interested in animal sexology engaged in studying the pattern of sexual behaviour of many animals and over the years came up with many startling statistics. It is significant even from the evolutionary point of view how the occurrence of “non reproductive” mating still prevails in spite of Natural Selection. Many questions need to be answered. And thankfully despite strong opposition from various quarters, scientists have devoted their time to this topic of research.

An argument put forward by the detractors of the notion that homosexuality is natural has been that animals on whom experiments have been performed are already stressed enough to elicit behavioural changes. Their argument, albeit a strong one, fails when the findings of several people working in the wild are jotted down. For example,  In early February 2004 the New York Times reported that a male pair of chinstrap penguins in the Central Park Zoo in New York City had successfully hatched and fostered a female chick from a fertile egg they had been given to incubate. Other penguins in New York zoos have also been reported to have formed same-sex pairs. But this does not imply in any way that penguins in zoos were somehow behaviourally compelled to mate with other members of their own sex. In a study it was reported that when male penguins were put in cages with their female counterparts, they showed aversion towards the sexual signals generated by the fairer sex.

As for the puritans who spend harrowing times worrying over “species continuation”, black swans show the way. The males engage in coitus with females, and when the latter lay eggs, snatches them away and hatches the eggs with his male partner.

Homosexuality has been reported in many animals we encounter in our daily lives, be it the humble house sparrow or the mighty lion, swans or even the bison. Even the majestic elephant derives pleasure in mounting on and playing with the trunk of his male partner. In fact, the African and Asiatic elephants who have to spend a long time away from their tribes develop homosexual relation with their male comrades.

Interestingly the genetic experiments to determine the locus of a homosexual gene have been carried out in the fruit fly Drosophila melanogaster. Multiple genes have been identified that can cause homosexual courtship and mating. These genes are thought to control behaviour through pheromones as well as altering the structure of the animal’s brains. These studies have also investigated the influence of environment on the likelihood of flies displaying homosexual behaviour. I have briefly talked about them in the last issue.

A study by Dr. Charles E. Roselli et al. at Oregon Health and Science University (in 2003) stated that homosexuality in male sheep is associated with a region in the brain of the rams called the “ ovine Sexually Dimorphic Nucleus” (oSDN), which is half the size of the corresponding region in heterosexual male sheep. The female oriented rams seem to secrete higher levels of the enzyme Aromatase which converts testosterone to estradiol, which typically governs the male sexual behaviours. I will discuss this paper in a later issue.

In conclusion I would reiterate my view that procreation may not be the sole reason for mating. More research should be dedicated to studying the precise causes of such widespread evidences of homosexual behaviour of animals. This would give us an insight into evolutionary mechanisms too.

I would like to sum up by saying that the very presence of homosexuality in the animal kingdom should make one realise that it is unnatural to classify homosexuality as unnatural.

In the next issue I would talk about some more instances of animal homosexuality and experiments that have been going on to locate the cause of homosexuality. Until then keep well.