Your life matters. You can't live through a day without making an impact on the world. And what's most important is to think about the impact of your actions on the world around you.

Only if we understand, can we care. Only if we care, we will help. Only if we help, we shall be saved.

Even chimps understand the concept - if a troop of chimps enters a fruit tree, they will only pick the fruits that are ripe and leave the others growing. That is sustainability.

There would be very little point in my exhausting myself and other conservationists themselves in trying to protect animals and habitats if we weren't at the same time raising young people to be better stewards.

I think the most important thing to do is to be willing to listen, willing to care, and willing to admit mistakes and change your ways for the better!

When I began in 1960, individuality wasn't an accepted thing to look for; it was about species-specific behaviour. But animal behaviour is not hard science. There's room for intuition.

If you consciously say 'I won't do it!' to yourself, then you have a good chance that you won't.