Includes bibliographical references (leaves 873-896). / xxxvi, 896 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Reports on 2 experiments which investigated exploratory & other behaviour in the laboratory rat during fixed-interval, variable-interval, variable-ration and differential reinforcement of low rates schedules of reinforcement (& subsequent extinction.) A third experiment investigated exploratory & other behaviours in an open-field Skinner box during a fixed-interval schedule, with a concurrently available water source. The final experiments were conducted on a qualitative analysis basis at Adelaide Zoo. A number of novel objects were presented to a group of six chimpanzees, and a different set of objects presented to a pair of caracals, in an attempt to facilitate exploratory behaviour and reduce abberant behaviours. / Thesis (Ph.D.)--Adelaide University, Dept. of Psychology, 2001