Harvard Professor of Psychology Marc Hauser believes that animals conceive the world in ways similar to humans, especially species like chimpanzees who live a rich social life. His field and laboratory experiments suggest that humans got their mechanisms for perception from animals. “Those mechanisms came free, courtesy of evolution,” Hauser says. Hauser and his colleagues are trying to determine what sorts of thinking processes are unique to humans and what processes we share with animals. The one that comes immediately to mind is language. “Animals have interesting thoughts, but the only way they can convey them is by grunts, shrieks, and other vocalizations, and by gestures,” Hauser points out. “When humans evolved speech, they liberated the kinds of thoughts nonhumans have. Feedback between language and thinking then boosted human self-awareness and other cognitive functions.”