Tell me in simple terms, I plead, why the male Y chromosome is deteriorating.

‘Basically,’ he says, taking a deep breath, ‘the Y chromosome is a male signifier. It evolves quite rapidly, but downhill. We now have the human DNA sequence and the surprise is to find that most of it is not functional. It’s either decayed, or it’s simply redundant. That’s true for the entire human chromosome sequence. If you look at the Y, though, that truth is multiplied maybe 30 times. It’s only got 20 genes on it, most of which are employed keeping the cell it’s in alive.’

the future is female