Abstract
Exploratory behavior is considered under the following categories: (1) extrinsic exploration in which the animal seeks information about conventional reinforcers such as food, (2) intrinsic exploration which is directed toward stimuli which may have no biological significance, further divided into inspective and inquisitive exploration. In the former the animal inspects a particular object; in the latter, the animal performs behavior to make a change in its environment, rather than merely responding to a change. Extrinsic exploration is synonymous with the ethological term, appetitive behavior. It is shown that much of the behavior indicative of frustration reported in intensively housed animals occurs when the appetitive component of a drive rather than the consummatory component, is prevented. Consideration of inspective exploration is necessary for good husbandry practice, for fear is an important competing response. Inquisitive exploration has not been widely investigated in infraprimate species, but the authors present several possible examples in the species of common agricultural animals. However, they suggest that the propensity to show this type of exploration may vary between closely related species. In environments barren to the extent of stifling exploration, animals may develop apathy, and its relevance to animal welfare is discussed.