The effect of all this has been for the heights of men and women to be pulled in opposite directions over time, meaning that men tend to be a few inches taller than women, on average.

If we cast a glance at our primate cousins, we can see that in gorillas, for example, the males are whoppers – twice the size of females, their stature being driven by the need for males to fight fiercely for exclusive sexual access to a harem of females. In the graceful and relatively peaceful gibbons, on the other hand, males and females are exactly the same size and live in monogamous pairs.

Humans have a degree of body-size difference somewhere in between gorillas and gibbons, so you can draw your own conclusions about what our sexual proclivities should be.

So used are we to men being taller than their wives or girlfriends that we make a huge fuss when some high-profile short guy hooks up with a girl that can look down on him. We wanted to know, for example, did Tom Cruise stand on a box for his marriage portrait with Katie Holmes, who is a good two inches taller than him?

And then there's France's mini-president Nicolas Sarkozy with his willowy wife, Carla Bruni, towering over him even in her flats. No more Louboutins for her, then. Why did Carla go for such a little bloke?

Well, if guys are on the short side, they need to have something else to bring to the mating marketplace. For Sarkozy, it's power. Read more