A number of interesting revelations to be had here, and all to do with our choices of ‘mate’.

male female

And by mate, I don’t mean the antipodean colloquialism meaning ‘friend’.  Nope, I mean mate as in, you know, someone you want to shag.  As it were.

The first revelation in this paper* is that, for the most part, we tend to choose mates who are similar to us. Certainly I’ve heard that we tend to pick people who look like us in some way – this is why so many longterm old couples look similar to each other, apparently.  Of course, to confuse things, we actually tend to like the smells of people whose immune system makeups are different than ours**. And choices also differ depending on whether it’s a long- or short-term decision.***

In addition, received wisdom is often that we should pick someone who’s different to us so that we ‘complement’ each other, or some such thing.

Anecdotally, and amusingly, this tendency to choose lookalikes doesn’t apply to anyone I’ve ever dated.  But still.

So yes.  Boys do, apparently, tend to pick people who look like them.  Except, it turns out, when they’re stressed.

It’s known that stress alters mate choice in animals, but up until now its effect on humans mate choice was somewhat less clear.  So, what do scientists now know, and how did they get there?

The researchers in question took two group of boys (well, men).  The first group they stressed, and the second group they didn’t – classic ‘control group’ stuff.  The stressed group got that way by immersing a hand in ice water for as long as they could handle it.  Yeesh.

They then took the two groups of men, and showed them either neutral pictures or ‘erotic’ nekkid lady pictures.  The nekkid lady pictures had had their faces modified either to look like whichever man was viewing the picture, or another man, or else hadn’t been modified at all.

And they observed.

And what they found was this: that stress in fact completely changes what the men found attractive.  When unstressed, their preference was for ladies who looked like them (i.e. whose faces had been modified to resemble their own).  When stressed, however, their preference switched to prefer ladies who looked like someone else or who had remained unmodified.

Of course, this makes me wonder whether the stressful lifestyles lived by so many of us might be changing men’s preferences.  Perhaps it’s only fair, given that it’s been shown that taking the contraceptive pill (also a commonplace behaviour) changes what women find attractive in men***!  Maybe that’s why my boyfriends have tended to look nothing like me, and not generally terribly masculine either :)


** Yes.  It’s true.  And why?  Because our immune systems impact the mix of bacteria inhabiting our skin (in a good way, everyone), which in turn affects our natural odour. So, the more like your own immune system someone else’s is, the more similar their bacterial makeup will be, and the less different they’ll smell – something which you’ll pickup as them not having a strong, nice smell.


* Lass-Hennemann, J., Deuter, C., Kuehl, L., Schulz, A., Blumenthal, T., & Schachinger, H. (2010). Effects of stress on human mating preferences: stressed individuals prefer dissimilar mates Proceedings of the Royal Society B: Biological Sciences DOI: 10.1098/rspb.2010.0258

*** Does Taking Birth Control Alter Women’s Sexual Choices? – The Primate Diaries

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