Previous research establishes that religious rituals can serve as important signals of commitment to the group and willingness to cooperate. Signaling displays can, however, carry diverse information to different recipients. The research team therefore investigated whether participation in (extreme) religious rituals could also be seen as a mate quality signal. In Mauritius, they asked unmarried young Tamil women and parents to rate dating profiles of young males to pick those they would choose (their daughter) to date and those they would choose (their daughter) to marry.
Visual backgrounds referring to ritual participation increased the chances of the profile to be selected, although for the young women only for the marriage option. For parents, the suggestion of ritual participation increased the desirability of the young men for both short-term and long-term relationships with their daughters. Photos related to more extreme forms of rituals were five times more likely to be picked by the parents.
You can find the paper here:
https://www.sciencedirect.com/science/article/pii/S2666622722000156
Jana Nenadalová, Piotr Szymanek (Jagiellonian University), and Neil Van Leeuwen (Georgia State University) received a grant from the Open Science of Religion initiative (supported by the John Templeton Foundation) for a virtual reality study.
In his thesis, titled Costly signaling theory of pilgrimage: The case study of pilgrimage to Santiago de Compostela, he studied whether pilgrimages may function as costly signals of commitment to group norms.
