Disturbing stories often lie behind those pictures. Many chimps have been drugged with muscle relaxers or alcohol to make them easier to handle. Some are trained to smoke cigarettes and guzzle beer. Orangutans are gentler than chimps, but still, they are not always gentle, and investigators say zoo trainers sometimes beat them with lead pipes wrapped in rolled-up newspapers to force them to perform tricks. Several years ago, the Indonesian police rescued a female orangutan who had been shaved and was being used as a prostitute at a brothel.