Public-service announcements typically seek to educate consumers regarding a given unhealthy practice, the assumption being that individuals will cease the harmful behavior once they are fully informed. Many intervention strategies have failed in curbing the targeted behaviors because these are not due to incomplete information but instead may also have a Darwinian-based etiology. Using sunbathing as a case analysis, it is shown how Darwinian theorizing (evolutionary psychology, life-history theory, gene-culture co-evolution, and memetic theory) can augment social marketers' ability to develop efficacious intervention strategies. © 2006 Wiley Periodicals, Inc.Numerous diseases have an etiology that stems from people's proclivities to engage in unhealthy practices and behaviors. Some of the contributing factors to cardiovascular disease include a sedentary lifestyle, smoking, and an unbalanced diet rich in animal and polysaturated fats. Alcoholism increases the likelihood of liver disease (e.g., cirrhosis) and vehicular injuries. The deleterious effects of anorexia nervosa stem from