Everyone knows that David Attenborough, renowned naturalist and narrator of the Planet Earth documentary series, is the second-wisest person in the world (behind only this guy, of course). So when he speaks up, the human race had better listen. And in a recent interview with the Radio Timeshe did just that.

We are a plague on the Earth. It’s not just climate change; it’s sheer space, places to grow food for this enormous horde. Either we limit our population growth or the natural world will do it for us, and the natural world is doing it for us right now.

We keep putting on programmes about famine in Ethiopia; that’s what’s happening. Too many people there. They can’t support themselves — and it’s not an inhuman thing to say. It’s the case. Until humanity manages to sort itself out and get a co-ordinated view about the planet it’s going to get worse and worse.