1.   Such an achievement is the exact contrary of the plight of the captive chimpanzee who cannot discover how to copulate.

2.   For six years, I had been observing the social behavior of a group of captive chimpanzees at the Arnhem Zoo in Holland.

3.   Investigators also found a fourth captive chimpanzee that was infected with a genetically distinct AIDS-like virus.

4.   It was, instead, like the virus isolated previously from the captive chimpanzee of unknown origin.

5.   The captive chimpanzees that were infected had not become ill.

6.   But so far, it has been found only in captive chimpanzees.