“The whole of science, and one is tempted to think the whole of the life of any thinking man, is trying to come to terms with the relationship between yourself and the natural world. Why are you here, and how do you fit in, and what's it all about.”

“All we can hope for is that the thing is going to slowly and imperceptibly shift. All I can say is that 50 years ago there were no such thing as environmental policies.”

“All our environmental problems become easier to solve with fewer people and harder - and ultimately impossible to solve - with ever more people.”

“There is no question that climate change is happening the only arguable point is what part humans are playing in it. ”

“I don't run a car, have never run a car. I could say that this is because I have this extremely tender environmentalist conscience, but the fact is I hate driving.”

“We are not overpopulated in an absolute sense; we've got the technology for 10 billion, probably 15 billion people, to live on this planet and live good lives. What we haven't done is developed our technology.”

“Many individuals are doing what they can. But real success can only come if there is a change in our societies and in our economics and in our politics.”

“It seems to me that the natural world is the greatest source of excitement the greatest source of visual beauty the greatest source of intellectual interest. It is the greatest source of so much in life that makes life worth living. ”

“I think a major element of jetlag is psychological. Nobody ever tells me what time it is at home.”

“I like animals. I like natural history. The travel bit is not the important bit. The travel bit is what you have to do in order to go and look at animals.”

“Before the BBC, I joined the Navy in order to travel.”