Association for Behavior Analysis International

The Association for Behavior Analysis International® (ABAI) is a nonprofit membership organization with the mission to contribute to the well-being of society by developing, enhancing, and supporting the growth and vitality of the science of behavior analysis through research, education, and practice.


45th Annual Convention; Chicago, IL; 2019

Event Details

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Invited Paper Session #464

What Evolutionary Theory Tells Us About Behavior

Monday, May 27, 2019
11:00 AM–11:50 AM
Swissôtel, Concourse Level, Zurich D
Area: PCH; Domain: Theory
Instruction Level: Intermediate
CE Instructor: William Baum, Ph.D.
Chair: Carsta Simon (Oslo Metropolitan University, Norway)
WILLIAM BAUM (University of California, Davis)
Dr. Baum received his BA in psychology from Harvard College in 1961. Originally a biology major, he switched to psychology after taking courses from B. F. Skinner and R. J. Herrnstein in his freshman and sophomore years. He attended Harvard University for graduate study in 1962, where he was supervised by Herrnstein and received his Ph.D. in 1966. He spent the year 1965–66 at Cambridge University, studying ethology at the Sub-Department of Animal Behavior. From 1966 to 1975, he held appointments as post-doctoral fellow, research associate, and assistant professor at Harvard University. He spent two years at the National Institutes of Health Laboratory for Brain, Evolution, and Behavior and then accepted an appointment in psychology at the University of New Hampshire in 1977. He retired from there in 1999. He currently has an appointment as associate researcher at the University of California, Davis and lives in San Francisco. His research concerns choice, molar behavior/environment relations, foraging, cultural evolution, and behaviorism. He is the author of a book, Understanding Behaviorism: Behavior, Culture, and Evolution.

Why do organisms and behavior exist? Organisms exist because genes that make organisms increase reproductive success. An organism’s behavior is its interactions with its environment. Behavior, on average and in the long run, functions to serve reproducing. Surviving usually serves reproducing, and other activities like maintaining health, maintaining relationships, and gaining resources usually serve surviving and sometimes directly serve reproducing. When phylogenetically important features of the environment vary in ways that can be tracked by physiological mechanisms, selection favors phenotypic plasticity. Part of phenotypic plasticity is behavioral plasticity. Phylogenetically important events (PIEs), such as presence of potential mates, predators, or prey, impact reproductive success and underpin selection for behavioral plasticity. PIEs induce activities that tend to mitigate threats and enhance benefits. Additionally, selection favors phenotypes that respond to covariance in the environment between PIEs and other events and between activities and PIEs. Events that covary with a PIE come to induce the same activities as the PIE, and activities that covary with a PIE come to be induced by the PIE. Induction is the mechanism of the Law of Allocation that governs the allocation of time among an organism’s activities.

Target Audience:

Board certified behavior analysts; licensed psychologists; graduate students.

Learning Objectives: At the conclusion of the presentation, participants will be able to: (1) understand why organisms exist; (2) understand why behavior exists; (3) understand why behavior must be extended in time.



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Modifed by Eddie Soh