The look of love – or the scent of seduction?

My first co-written article featured in Student Direct : Mancunion, originally written by Ms Emma Bishop and edited by me! This article was also published online on the SD website.

Everyone has their own idea of who is their ‘perfect’ man or woman although we can’t always tell why we find someone attractive. So what is it exactly that draws you to some people, and not others? Research seems to suggest that the answer lies within evolution.

You probably thought that good looks is the main factor determining attraction. Luckily, science has shown that humans are not quite as superficial as this, as a person’s unique smell also plays a role. Have you ever found someone’s scent irresistible? This is evolution’s way of attracting you to someone with a different immune system to your own. Why? To make healthier and more infection-resistant offspring. In molecular terms this means that your ideal man or woman will have a different molecule involved in your immune response, called Major Histocompatibility Complex or MCH.

During fertilisation, a unique mixture of the mother’s and father’s genes encoding for MHC will be passed on to the offspring. When the two genes are different from each other, genetic variation is produced and this can in turn give rise to a stronger immune system. Thus, one way to explain attraction is that it is based on the differences in your and your love interest’s genes.

Amazingly, your brain can recognise different versions of MCH and signal a potential partner’s evolutionary compatibility. The smell of these molecules can determine whether someone is an ideal partner if they vary from your own MHC. In fact, some dating websites have begun to use this difference in immune systems to actually match up couples via the internet! These so-called ‘DNA dating sites’, such as www.scientificmatch.com, promise that genetic variation between couples leads to not only higher fertility rates, but also better sex and ‘a lower chance of cheating’ on your partner!

So apart from there being literal ‘chemistry’ between an ideal couple, do superficial traits still contribute to attraction? The answer is yes. In women, large eyes and breasts tend to be rated as ‘more attractive’ to men. Again evolution plays a role, in that women with larger eyes and breasts tend to have more of the sex hormone oestrogen produced by their body. This means that these females are more likely to be fertile, and this is interestingly enough signalled in their looks. So, although most men may not realise it, when settling for a girl with either of these attributes, they are unconsciously choosing a woman that is more fertile and will most likely produce more offspring.

Such scientific evidence becomes even more intriguing when put in a wider context. We must ask ourselves: in a society where women are pressurised to push up their breasts and lash on the mascara – are we actually hampering with natural selection?