If you watch animals objectively for any length of time, you're driven to the conclusion that their main aim in life is to pass on their genes to the next generation.

Crying wolf is a real danger.

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 coordinated view about the planet it’s going to get worse and worse.

Clearly we could devastate the world... as far as we know, the Earth is the only place in the universe where there is life. Its continued survival now rests in our hands

It's like saying that two and two equals four, but if you wish to believe it, it could also be five ... Evolution is not a theory; it is a fact, every bit as much as the historical fact that William the Conqueror landed in 1066.

The savage, rocky shores of Christmas Island, 200 miles south of Java, in the Indian Ocean. It's November, the moon is in its third quarter, and the sun is just setting. In a few hours from now, on this very shore, a thousand million lives will be launched.

How could I look my grandchildren in the eye and say I knew what was happening to the world and did nothing.