Trait Social Anxiety as a Conditional Adaptation: A Developmental and Evolutionary Framework

Individuals with trait social anxiety are disposed to be wary of others. Although feeling social anxiety is unpleasant, evolutionary psychologists consider it to be an adaptation. In current models, social anxiety is described as functioning to have helped our prehistoric ancestors avoid social threat by warning individuals when their interactions with other group members were likely to be negative and motivating them to act in ways to prevent conflict or limit its damage. Thus, trait social anxiety is thought to have evolved in our species because it allowed our ancestors to preserve their relationships and maintain their positions in social hierarchies. While we agree with this conclusion drawn by existing evolutionary models, we believe that there is an important element missing in these explanations: the role that individual development has played in the evolution of trait social anxiety. We propose a new model, which argues for trait social anxiety to be considered a conditional adaptation; that is, the trait should develop as a response to cues in the early childhood environment in order to prepare individuals to face social threat in adulthood. Our evolutionary model can provide new insights into how trait social anxiety has persisted in our species and how it functions in the modern world.