Whilst my last post focused on sex primarily in a reproductive context, animals have sex for many reasons, just like humans do. However, “for decades, biologists, anthropologists and psychologists have suppressed inconvenient evidence of homosexual behaviour among the human and nonhuman animals they observed” (Julien Dugnoille).
I’m going to start by looking at same sex activity as it’s one clear thread of evidence that not all animal sex is for reproduction.
There are many more bisexual animals than we tend to think and note I’m saying bisexual because often the animals aren’t solely engaging in same sex activity (which I’m going to say because same sex sex is a mouthful!). Often, they are also having sex with the opposite sex when the opportunities arise. The BBC also discusses whether we can claim some animals are homosexual as opposed to bisexual.
Ultimately, these are human enforced labels and as Eric Anderson says:
“Animals don’t do sexual identity. They just do sex.”
You’ve quite possibly heard about the ‘gay’ penguins in a zoo. They coupled up and started building their nest and sitting on rocks. When the zoo realised what was going on, they placed an egg from a female penguin who was struggling to care for it in the nest. The male penguins successfully incubated and raised the chick.
Same sex dolphins can become partners for life engaging in sexual behaviour, for example males can have a temporary female relationship but will return to the initial male partner afterwards. Further, two male couples can join up to become a foursome. One theory is that it helps to have a companion when feeding and resting because they can look out for danger.
Some male greylag geese pair up and when it’s time to raise children, they find a female and raise them together as a trio. Some don’t but research shows the advantage of a trio; there is better defence against predators, the female has a higher social rank and better chance of survival and the female has more time to devote to her chicks because two males are helping. After the chicks are raised, the males stay together whilst the female leaves.
In a reverse make up, roughly 2% of oystercatcher breeding groups are made up of two females and one male. Additionally, up to a quarter of black swan families include parents of the same sex (Scientific American) and in some bird species, males steal eggs from females and raise them in same-sex unions.
Whilst these examples might feel like the exception to the rule, observers have witnessed as many as 1500 species of wild and captive animals engaging in same sex activity.
“Homosexual behaviours is surprisingly common in their animal kingdom. It may be adaptive- helping animals to get along, maintain fecundity and protect their young.”
– Emily Driscoll, ScientificAmerican.com
Moving on from same sex activity to other non reproductive sexual activity, we find types of fruit bats who engage in oral sex, both female on male and male on female. There is also masturbation and attempts to mate with the dead…
But what is all this sexual activity about? Obviously, some sex is about reproduction, but pleasure, bonding and keeping the peace are all reasons for engaging in sex.
Bonding can be important for group species and strong bonds can be very helpful when facing off rivals or seeking protection from other group members. This bond is also important in maintaining a strong group dynamic and sexual activities can diffuse social tensions. Another type of bond is that of a parenting couple who may engage in sexual activity to maintain their bond whilst raising their young.
It’s interesting to look at an example, the bonobo. Bonobos use sex to greet each other, to resolve conflict and for pleasure. They engage in mutual masturbation, oral sex and penis fencing and are in general a very peaceful species. Perhaps humans would be more chilled out if we had more sex?
But lets take a second to focus back on masturbation. As well as humans, many other primates engage in masturbation and this can range from simple stimulation with their hands through to using twigs and leaves and other inanimate objects. Females have been observed inserting objects into their vaginas and one male orangutan created his own sex toy:
“In one display of sexual ingenuity, a male orangutan created his own ‘sex toy’ using a large leaf, through which he poked a hole with his finger. He then proceeded to thrust his erect penis through the hole for additional stimulation.”
– Carin Bondar
Sexual activity may also help some animals to reiterate their social hierarchy and may allow individuals to climb the ranks.
In some cases, animals may engage in non reproductive sexual activities such as same sex sex in order to gain sexual experience. It’s interesting to note that it seems that same sex activity appears to be more common in captivity (although that could just be because its easier to observe), possibly because of a lack of alternative options and greater need for stress release. In a similar way, you tend to find higher than ‘natural’ rates of same sex activity in prisons.
Time for another example! Most penguins are not monogamous but it is by turning to Adelie penguins that we really get our eyes opened. A scientific paper from 1915 had been hidden away for years, labelled not for publication and when it was rediscovered in 2009, it became clear why scientists of the time were reluctant to publicise the observations.
“They were ‘gangs of hooligan cocks’ whose ‘passions seem to have passed beyond their control’ and whose ‘constant acts of depravity’ run the gamut of masturbation, recreational sex and homosexual behaviour to gang rape, necrophilia and paedophilia. Chicks were ‘sexually misused by these hooligans’, including one who ‘misused it before the very eyes of its parent’. Strayed chicks were crushed and ‘very often suffer indignity and death at the hands of these hooligan cocks’.”
– Lucy Cooke quoting Dr George Murray Levick
Whilst this all sounds incredibly shocking, there is an explanation. Adelies get together in October, flooded with hormones and only a few weeks to mate. Young males are inexperienced and don’t really know what to do or how to act and this can lead to some questionable activity… In their hormonal eyes, a frozen penguin in the right position can look a lot like an interested female… Apparently necrophilia isn’t just restricted to penguins… Lucy Cooke references pigeons mounting dead house martins, male house sparrows attempting to mate with dead females and the same going on with a couple of pheasants…
In addition to all of this wonderfully interesting and fun goings on, we have those animals which change sex.