Some Basic Ethology
In the early portion of the 20th century, a group of European naturalists began to systematically study the behavior of animals, mainly by observing these behaviors while the animals went about their normal lives in the wild. The main focus was to identify the innate behavior patterns of each species, classify them according to function, and identify the physiological and stimulus conditions necessary for the performance of each pattern. This new, scientific study of behavior came to be known as ethology.
Characteristics of the Ethological Approach
The ethological approach to the study of behavior is characterized by the following:
- Naturalistic observation -- observation of the animals in their natural environments, undisturbed by the presence of the observers.
- Focus on "species typical" behavior -- ethologists work to identify specific patterns of behavior that occur in every member of the species. Although learning has not been entirely ignored by ethologists, the main emphasis is on innate behavior.
- Classification -- behavior patterns are classified according to function (purpose served, e.g., communication, navigation, territorial defense) and form (what specific actions occur, in what sequence, etc).
- Experimental testing of hypotheses -- naturalistic observation may suggest what stimulus conditions serve to trigger a given behavior, but only experiments can actually nail down the specific requirements.
Some Ethological Terms
Ethologists have developed their own special vocabulary; here are a few key terms:
- Fixed action pattern -- a specific pattern of actions that meets the
following criteria:
- It is part of the repertoire of all members of the species.
- The ability to perform it is not the result of learning.
- If a sequence of behavior, the sequence, once initiated, continues in a rigid order to completion without further stimulus support. (This criterion distinguishes the FAP from a reaction chain, see below.)
- Sign or releasor stimulus -- a specific stimulus that triggers a fixed action pattern. The effective stimulus may include several elements that must be present together.
- Innate releasing mechanism -- an hypothetical mechanism that triggers ("releases") the fixed action pattern when it detects that the releasor is present.
- Supernormal stimulus -- an unnatural stimulus that functions as a super-effective releasor stimulus.
- Reaction chain -- A series of behaviors in which each behavior produces a releasor stimulus for the next behavior.
Classic Ethology versus Classic Behaviorism
Ethologists and Behaviorists both claim to be studying the behavior of organisms, but their primary methods and goals have been very different:
- Ethologists have tended to focus on instinctive patterns of behavior, behaviorists on arbitrary behaviors that the organism acquires by interacting with the environment (learned behaviors).
- Ethologists have been concerned with identifying innate behavior patterns and their triggers and supporting conditions, behaviorists with identifying general laws affecting the acquisition and maintenance of learned behaviors.
- Ethologists have conducted most of their observations within the natural environment of the target species, behaviorists within the artificial environment of the laboratory, where the relevant variables can be tightly controlled.
- Ethologists have been interested in examining as broad a variety of species as possible in order to identify similarities and differences across species (comparative analysis), behaviorists in examining only a few "representative" species, such as the laboratory rat or pigeon, that exhibit good abilities to learn arbitrary behaviors.
- At least initially, both approaches tended to explain the occurrence of behavior in terms of a reflex-like model, in which stimuli elicit behavioral responses.