The idea that humans may have pheromones is a long debated one, as far back as the 19th century in fact. What would it mean if they did? That humans become sexually aroused by someone else’s smell. It happens in animals, why not for us?
Until now, experiments haven’t provided much proof of a human pheromone. Pigs, insects, cats, apes – yes. Androstenone, a pheromone naturally produced by boars, stimulates sexual arousal in female pigs. However, structurally related chemicals to the boar pheromone have been found in humans. Men and women secrete steroids, Androstadien and EST respectively, in sweat, saliva and semen. Indeed, when sniffing the male pheromone in the experiment, heterosexual women reported an enhanced mood and even slight arousal, while heterosexual men did not. Moreover, women were only affected when the scientist conducting the experiment was male, suggesting there’s certainly some contextual significance.
Proof wasn’t just found in reports, however. When women smelt the male pheromone, activity in a specific brain region increased. On the other hand, upon smelling the female pheromone, nothing happened. When heterosexual men smelt the female pheromone, brain activity was increased in a different area of the brain to women’s.
Could this mean that we can bottle sex?
Perhaps the Lynx adverts will finally have some truth in them. Perhaps the Marquis de Sade was right after all. You can imagine the Daily Mail headline, ‘Scientists plunge humanity into a gigantic orgy’. Luckily this is very unlikely given the relatively small effects seen, and the myriad of other factors which govern human sexual attraction. Women didn’t simply lunge at the nearest man, but reported that they were more attracted to some pheromones presented than others. Interestingly this is not the first time scientists have found that people’s smell can alter attraction. It has also been found that people are more attracted to the odours of those with opposing, and therefore complementary, genes which dictate their immune systems. People are therefore attracted to those whom their children would have the best combination of both of their genes, in terms of fighting colds, for example. Furthermore it sets a biological motivation against incest, which is rather reassuring.
Where the experiment gets more interesting is when homosexual men and women are tested.
In these cases, the brain activity was stimulated by the opposite pheromone to heterosexual men and women; gay men are attracted to male pheromones, with corresponding brain activation. So, the smell-arousal dimorphism relates to sexual orientation, not gender. Unfortunately for Putin and Scientology, nothing’s going to be turning gay people straight any time soon.
The findings fit with a growing body of evidence that homosexuality has a strong genetic root. An interesting future experiment would be to test homosexual animals for differences in their hormonal behaviours, although where the funding to investigate gay animals will come from is unclear in the present climate.
Does this mean our sexual arousal could be purely dictated by our genes? If so, our sexual arousal mimics that of animals, sex is indeed just animalistic. Gone are the whimsical theories that sex is a way of communicating, or that our lust is specifically directed to one person. If men and women have biologically set arousal systems, then all this monogamy, marriage and morality we associate with sex is actually suppressing our natural instincts.
If sexual arousal is just physical, where do we draw the line?
Yet we’re not like other animals. Our absurdly big brain evolved to help us to navigate around our increasingly social environment. If our higher cognition is good for anything, it should be to control and direct our physical desires. In Sex in the Head Professor Seiriol Morgan, a Philosophy lecturer at Bristol University, points out that our ability to reason affects the majority of our instincts, particularly complex ones like desire. Someone who wishes to eat healthily will alter their diet, and come to desire healthy food. Smell isn’t the only thing that dictates desire; it’s the complex social relationships with which it interacts. The same can be said for chocolate: it’s not just the smell of it that is so appealing. There’s the taste, the way it makes you feel and your own personal relationship with that goddam seductive bar of Galaxy which dictates your desire.
Sex and chocolate alike. There’s more to it than just smell.
By Miles Apart and Claudia Knowles