Abstract
In reply to commentary on our target article, we supply further evidence and hypotheses in the description of ritualized behaviors in humans. Reactions to indirect fitness threats probably activate specialized precaution systems rather than a unified form of danger-avoidance or causal reasoning. Impairment of precaution systems may be present in pathologies other than obsessive-compulsive disorder (OCD), autism in particular. Ritualized behavior is attention-grabbing enough to be culturally transmitted whether or not it is associated with group identity, cohesion, or with any other social aspect of collective ceremonies. (Published Online February 8 2007).