Discriminating the relation between relations: The role of entropy in abstract conceptualization by baboons (Papio papio) and humans (Homo sapiens)

Two baboons (Papio papio) successfully learned relational matching-to-sampl e: They picked the choice display that involved the same relation among 16 pictures (same or different) as the sample display, although the sample dis play shared no pictures with the choice displays. The baboons generalized r elational matching behavior to sample displays created from novel pictures. Further experiments varying the number of sample pictures and the mixture of same and different sample pictures suggested that entropy plays a key ro le in the baboons' conceptual behavior. Two humans (Homo sapiens) were simi larly trained and tested; their behavior was both similar to and different from the baboons' behavior. The results suggest that animals other than hum ans and chimpanzees can discriminate the relation between relations. They f urther suggest that entropy detection may underlie same-different conceptua lization, but that additional processes may participate in human conceptual ization.