Chimps act the way they feel unless they are afraid of reprisal if they do so. But that doesn't apply to humans.

Surely it should be a matter of moral responsibility that we humans, different from other animals mainly by virtue of our more highly developed intellect and, with it, our greater capacity for understanding and compassion, ensure that medical progress slowly detaches its roots from the manure of non-human animal suffering and despair.

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 a chimp who has been abused horribly by humans can help a human friend in a time of need, how much more should we help the animals - and other people for that matter - in their time of need?

I do not want to discuss evolution in such depth, however, only touch on it from my own perspective: from the moment when I stood on the Serengeti plains holding the fossilized bones of ancient creatures in my hands to the moment when, staring into the eyes of a chimpanzee, I saw a thinking, reasoning personality looking back. You may not believe in evolution, and that is all right. How we humans came to be the way we are is far less important than how we should act now to get out of the mess we have made for ourselves.

It's not a pretty picture, but there are reasons for hope.

Here we are, arguably the most intelligent being that's ever walked planet Earth, with this extraordinary brain ... and yet we're destroying the only home we have.