Graphical AbstractHighlights d An ABM is used to study the cultural evolution of sustainable behaviors d Behaviors emerge as a function of affordances, social learning, and habits d The affordances in an environment have a major effect on behavior adoption d The ABM is validated against cycling behaviors in Copenhagen Authors Roope Oskari Kaaronen, Nikita Strelkovskii Correspondence roope.kaaronen@helsinki.fi In Brief Kaaronen and Strelkovskii have designed an agent-based model to study the cultural evolution of sustainable behaviors. Behaviors emerge as a product of personal, environmental, and social factors. Particularly the structure of the environment has an effect on the adoption of pro-environmental behaviors. Even linear changes in pro-environmental affordances (action opportunities) can trigger non-linear collective behavior change. The model is validated against cycling behaviors in Copenhagen. This model gives further justification for policies and urban design that make proenvironmental behavior psychologically salient, accessible, and easy.