Has anybody read "Demonic Males: Apes and the Origins of Human Violence?"

"You will be killed!" the man at the Burundian embassy in Kampala said, in a bizarrely cheerful voice, as he stamped our visas.

But killing was the reason we were in Africa. Dale Peterson and I were exploring the deep origins of human violence, back to the time before our species diverged from rainforest apes, 5 to 6 million years ago. Not only ancestral to humans, those early rainforest apes were also part of a genetic line now represented by the four modern great ape species: orangutans, gorillas, chimpanzees, and bonobos. Both of us had already observed orangutans in Borneo and gorillas and chimpanzees in Africa, but neither of us had yet seen the fourth and rarest ape, the bonobo, in the wild.

To get to the bonobos, we first had to reach Bukavu, a town on the eastern side of Zaire, just across the border from Rwanda. In Bukavu, we would pick up a single-engine plane and fly west for three hours across a sea of forest until, having passed more than halfway across the continent, we would find an airstrip and a little town isolated in that great green world. Near the town was the small pocket of rainforest where the bonobos lived.

To fly directly from Uganda to Zaire was impossible because the shaky Zairean government, fighting for control of the country, had closed all international airports, and driving overland was not advised because of discouraging reports about bandits and guerrillas. And so we had decided to fly south from Uganda into Burundi, then drive a rented van through Burundi and Rwanda, and on into eastern Zaire.