Women of child-bearing age steadily run out of eggs by the continuous process of cell death. While reading a copy of the Guardian carefully from cover to cover, a normal woman will have lost on average two eggs - while, typically, a normal man will have made 70,000 new sperm.

I don't much like being a public figure, because so often how people appear is not how they really are, and I think one of the issues about our society is that we make judgments about people on the basis of very flimsy evidence.

Scientists need to be prepared to engage, and the best people to engage with are students, ideally from primary school because there's no question that their capacity to work out complex things is extremely good.

Childhood is not dead. Children were worse off when we were hunter-gatherers; they were threatened in medieval times and exploited during the Industrial Revolution. Was it any better in the time of Charles Kingsley or Charles Dickens?

That Britain today is a liberal society is largely because of the philosophy and outlook of the Anglican Church, which did so much to shape our core values in the past few centuries.

We can't any longer have the conventional understanding of genetics which everybody peddles because it is increasingly obvious that epigenetics - actually things which influence the genome's function - are much more important than we realised.

I was born with my moustache and, no, I've never been tempted to shave it off. I don't spend a lot of time worrying about my face and, like Gilbert and Sullivan's Katisha, my best feature is my left shoulder-blade.