And anyway, eventually, practically up at the other end of this lake from the camp, so what? Six miles, something like that, and we heard the sound of chimpanzees [chimp sound] and Doubla and Vicky really quietly paddled the little fishing dugout onto the mud, and then we covered ourselves in mud. I mean, I was taking instructions, absolutely caked with black mud, and then went forward on our stomachs, hoping not to meet a python on the way, and eventually got right underneath an enormous... well, they all seem big, chimpanzees. Very, very old chimp, perfectly obviously. I mean, apart from the fact that he was black, he looked very like James Fenton, because he was bald. And they have surprisingly, sort of, mobile lips, and very slowly, he was going and eating leaves. And then awful effort of law, eating a leaf the other side. And I thought, 'God, I'd be terrible as a scientist in animal behaviour.' I was really bored after. And moved. And then he looked down and we looked at each other, and he obviously thought this was the most disgusting thing he had seen in all his many years.

And he put a hand up over his face, just like James does. And then he thought. You could see he was thinking, and he got to his feet on the bough, and grabbed a couple of... what would they be called? Those saplings coming out of the bough, and he went: [chimp ululation] and I thought, wow. And then, the signal sent, I suppose, he just peed right on me. You feel very unwanted. And then he swung around and defecated. Now, that sounds sort of civilised, but no. It was a shotgun blast of little fruity dropping. Well, pellets. And then everybody else joined in: [chimp ululation] and they were big, these guys. And young males. Instead of rushing off, as the story would have it they do, coming closer and closer, climbing down the tree, and this maelstrom of noise, incredible noise. I thought, this is a very, very impressive display, sort of in a patronising way. And then I remembered Jane Goodall's story that actually, a chimpanzee's idea of a really good day out is to go and grab a monkey of any kind by the ankles, bash its head against a tree and eat it. A meat stick. And it was frightening. I thought, no wonder socially insensitive leopards turn and run. These young guys, with their enormous long arms, were gathering, some of them, behind us, and slapping the ground, boom, with such violence. And not before time, I thought, Vicky and Doubla stood up, and with their machetes, they wacked the boughs of the trees. And gradually, I mean they didn't run off, they ambled off, still very angry being disturbed in their eating of these boring leaves. And tremendous, unbelievable noise. I've never been surrounded by... well, I've never been pissed on by so many people.