I often had the impression that the bicycle I used to get to the chimpanzee enclosure in Arnhem Zoo was a time machine, taking me five million years back in time. After picking up the key at the entrance to the zoo, I went to the observation room next to the two-acre chimpanzee island. Having entered the observation room, I would open a few windows and wait for the chimpanzees to be released onto the enclosure by the keeper.
After having greeted one another they would start another day, leading their own lives, comparable to that of their conspecifics in Africa in many ways. I would be able to observe their behaviour in detail. For several years, that was my job: observing and studying chimpanzees. My observations in Arnhem often gave me the feeling I was watching ancestors from a distant past at a time when, having eaten, their main interest is one another.
