I believe that the tragedy [like terror attack] that's caused so much grief and suffering to so many thousands and thousands of people has also served as a call to action, because many people now are re-examining their own value systems, and the churches, temples, mosques and cathedrals are packed to overflowing for the first time in years.

Primates are very territorial. It is in their nature to protect their food resources as well as their females and young.

Especially now when views are becoming more polarized, we must work to understand each other across political, religious and national boundaries.

I shouldn't have named the chimps. It wasn't scientific. I didn't know. I knew nothing. And worse sin of all was that I was ascribing to them emotions like happiness, sadness and so forth.

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.

You know the old expression "We haven't inherited the world from our parents, we've borrowed it from our children"? Well it's just not true. We haven't borrowed anything.

My favorite animals are dogs.