Sniffing out sex

The human nose serves a variety of functions. It is a filter of air, an inhaler of air, an expeller of unwanted material, an object of admiration, an object of scorn, and sometimes a vehicle for assorted jewellery. Of course a prime function of the human nose is to smell the world around us. Through smell we can detect, danger, fear, poison, emotion, and yes, sex. According to new research you can determine someone’s gender just by sniffing them but that capacity is affected by your own sexuality.

It has been known for a long while that the human body produces odour molecules that differ according to gender and these researchers say that these molecules can be detected and indicate the gender of a person without the smeller ever being aware of it. The molecules that do this are steroid hormones; androstadienone in men and oestratetraenol in women.

In the new study subjects were asked to watch “point-light walkers” (PLWs) move on a screen. PLWs are 15 dots located at the major points of a human body representing the 12 major joints plus the pelvis, thorax, and head. Watching the PLWs meant that the subjects were watching “people” move without actually seeing a person’s features. The gaits of the PLWs were digitally altered to make them appear more masculine or feminine.

The subjects were asked to decide whether each PLW was more masculine or more feminine. They did this on a few separate occasions over a period of days while they were being exposed to an aerosolised solution of either androstadienone, oestratetraenol, or placebo. Each solution smelled of cloves.

The results showed that heterosexual females, but not males, were biased to perceive the walkers as masculine when they were exposed to androstadienone. Equally, heterosexual males, but not females, were biased to perceive the walkers as more feminine when exposed to oestratetraenol.

However, homosexual males responded in the same way to the hormones as did heterosexual females. The responses of homosexual or bisexual females fell between those of heterosexual males and females.

Essentially your nose is scoping to detect potential sexual partners based on the pheromones they are exuding and it is all happening without being able to smell anything on a conscious level.

So trust your nose; it knows.