Is he fit?
Faces play a big part in how attractive we think people are. Some notions of beauty appear to be shared but there is also a degree of individuality or taste.
As well as revealing something about state of mind, through expressions, the face also offers insight into our biology. Symmetry may send signals about a strong genetic stock. But the shape of our face also reflects a hormonal influence, largely due to the masculinising effects of testosterone. This hormone is responsible for the classic features of the he-man - prominent cheekbones, jutting jaw.
So do women favour the 'testosteronised man', the alpha-male packed full of male hormone? Since testosterone is not a wholly good thing for a man - it suppresses the immune system - thriving while pumped full of testosterone could be seen as a good measure of 'fitness' (in the Darwinian sense).
In fact, although masculine faces are perceived as dominant, there is no clear link between masculinity and desirability. Jude Law is more than a match for Sylvester Stallone.
Interestingly, women's preferences for masculine faces vary slightly across their menstrual cycle. At times of peak fertility, their preference increases for more masculine faces (and deeper voices and more manly bodies and smells). However, the effect is seen only in the context of a short-term relationship, rather than longer-term commitment.
