Nature-Nurture Debate

An ongoing debate in psychology about the etiology of traits and behavior. It inquires as to the influence of genetic inheritance (biological nature) and environmental conditions (nurture) on personality and human behavior. This debate was much more clearly demarcated in the early 20th century, when behaviorism was prominent. Behaviorists argued strongly for the “nurture” side of the debate, asserting that all behavior is determined by learning and experience. Those on the “nature” side of the debate emphasized the role of biological processes in human development, arguing that human development proceeds through a series of genetically determined changes that unfold according to a biologically determined path.

Although the debate continues today, it is now a debate about emphasis; modern psychologists recognize that human behavior is influenced by a combination of genetics and environment and argue over the relative contributions of these factors to particular behaviors. Behavioral genetics is the study of how genes and environments work together to shape behavior; the research methods commonly employed to investigate these questions include twin studies and adoption studies. Evidence shows that genes account for about half of the variation observed in personality charac teristics, but whether genetics influences the develop ment of personality and behavior patterns depends largely on the environment in which a child is raised. Behavioral genetics also aims to identify the particular genes that contribute to hereditary behavior. However, this can be a difficult task; while some physical traits are determined by a single gene, many behavioral patterns and personality characteristics are driven by a complex combination of multiple genes interacting with environ mental factors. For more information, see Rose (2001).