I recently saw a video of myself giving a public lecture. It's an interesting experience, watching yourself talk. There is the voice that is not immediately recognisable as my own. And there are idiosyncratic physical gestures too...the smile, the posture, the tilt of the head, and...the flamboyant hand movements. Man, am I really that gay? Scientists have shown that there are, indeed, behavioural differences between gay and straight men in the way that we gesture. I guess non-scientists who pick up on those cues call it gaydar. There are important morphological differences as well. The most intriguing is the difference in the so called 'second-to-fourth-digit' ratio between gay and straight men. Imagine my horror a few years back (when I was not yet out of the closet) when a colleague asked to see my hand. After inspecting it thoughtfully, she declared "you're gay". Don't believe that a man's hand can reveal his sexuality? If you're a bloke, do the test yourself. Lay your hand on a flat surface with the fingers close together. Which is longer? The second digit (i.e. index finger) or the fourth? Compared to a straight man, the index finger on a gay man should be longer than the fourth digit. Not quite sure how this would work for men that sit somewhere in the middle of the Kinsey scale.