chimpanzee• Premack's prizepupil was a wild-born chimpanzee, Sarah. 4.• Least developed in the gorilla but greater in chimpanzees and australopithecines, with formation of incisivecanal.• It does, however, spend more time than chimpanzees in trees, from which it occasionally drops branches on to predators.• So, instead, they used a large puppet and two actors who take turns dressing as the chimpanzee.• Wake up and smell the chimpanzees!• The chimpanzee is highly mobile and semi-terrestrial, showing great adaptability to a widerange of woodlands.• If they did not use chimpanzees, then surely they could produce evidence of what they did use.