In the bottlenose world, homosexual activity occurs with about the same frequency as heterosexual play. Male bottlenose dolphins are generally bisexual - but they do go through periods of being exclusively homosexual. Homosexuality is common among lions as well. Two to four males often form what is known as a coalition, where they work together to court female lions. They depend on each other to fend off other coalitions. To ensure loyalty, male lions strengthen their bonds by having sex with each other.
Many researchers refer to this behavior as your classical "bromance" rather than homosexual pairing. Homosexual activity between male bisons is more common than heterosexual copulation. That's because female bisons only mate with bulls about once a year. During mating season, males that get the urge engage in same-sex activities several times a day. And so, more than 50 percent of mounting in young bison males happens among the same gender.
Both female and male macaques engage in same-sex activity. But while males usually only do so for a night, females form intense bonds with each other and are usually monogamous. In some macaque populations, homosexual behavior among females is not only common, but the norm. When not mating, these females stay close together to sleep and groom, and defend each other from outside enemies. But are these assumptions well-founded? We argue that they are not, and that they are perhaps rooted more in cultural norms than in scientific rigor.
First, the costs of SSB are often assumed to be high because engaging in SSB leads individuals to waste time, energy and resources without obvious gains in fitness.
The costliness of SSB is often emphasized in comparison to the benefits of having sex with an individual of a different sex different-sex sexual behavior or DSB. While DSB can certainly lead more obviously to higher fitness through the production of offspring, these comparisons assume that DSB is highly efficient. However, animals often mate many times to produce just a few offspring, and acts of DSB frequently do not result in reproduction for a whole host of reasons.
In other words, DSB can be costly too, and it is rarely clear whether mating with an individual of the same sex is comparatively costlier than any other reason why sexual behavior may not lead to reproduction. As far as we can tell, no such evolutionary scenario has been considered for SSB. Finally, both of these assumptions underlying previous research on SSB are reinforced by a heteronormative worldview under which SSB is seen as aberrant, perhaps explaining where these assumptions came from and why they were so rarely questioned.
In our paper, we argue for a subtle shift in perspective that offers new ways of understanding the diverse and endlessly fascinating world of animal sex, including SSB. We explicitly move away from viewing SSB as aberrant or as mutually exclusive from DSB, instead acknowledging that individuals and populations of animals can engage in a spectrum of sexual behaviors that include both DSB and SSB in a vast array of combinations.
This perspective leads us to propose the following alternative scenario: what if SSB has been around since animals began to engage in sexual behavior of any kind? In our hypothesis, the ancestral animal species mated indiscriminately with regard to sex, i. Homosexual and bisexual activity between animals has been well documented, with more than 1, species recorded in engaging in same-sex sexual behaviour.
And why, when animals have evolved over millennia, has same-sex sexual behaviour repeatedly evolved and persisted? By shifting the lens through which we study animal sexual behaviour, we can more fruitfully examine the evolutionary history of diverse sexual strategies. The first is that same-sex behaviour has high costs because individuals spend time and energy on activities offering no potential for reproductive success.
Home Current Issue Do Animals Exhibit Homosexuality? By Arash Fereydooni.
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