Perrett photographs students' faces and changes them into the opposite sex. Then he asks them to choose which one of two faces they fancy the most. The students always fancy the face that's an opposite-sex version of themselves - even though they don't recognise it as such.
Perrett suggests that we find our own faces attractive because they remind us of our parents, whose faces we looked at constantly during our childhood.
Should I think about science when dating?So, should you go off and buy pheromone spray, get a nose job and start squeezing yourself into corsets?
Well, some scientists think that it doesn't really matter at all. 'You must always think about a person's free will when it comes to attraction,' says Rob Elder. 'Many researchers say that pheromones and body shape only get you so far.'
After that, the course of true love is determined by a whole load of other things, from your taste in music to your kissing technique...
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