Assortative mating based on cooperativeness and generosity.

Area of Science:

• Evolutionary Biology
• Behavioral Ecology
• Social Psychology

Background:

• Cooperative behavior and generosity can signal an individual's quality as a potential mate.
• Such costly traits might be criteria in mate choice, potentially leading to assortative mating.
• Previous studies suggest similarity in altruistic traits among couples, but relied on self-reports and lacked conclusive evidence on convergence or preference.

Purpose of the Study:

• To investigate whether similarity in cooperative behavior and generosity exists between spouses.
• To determine if observed similarity is a result of initial mate selection (assortment) or changes in behavior after pairing (convergence).

Main Methods:

• Conducted a field experiment in rural villages in Senegal.
• Measured husbands' and wives' contributions to a public good.
• Assessed participants' charity donations.

Main Results:

• Husbands and wives demonstrated significant similarity in their contributions to a public good.
• Couples also showed similarity in their levels of charity donations.
• Statistical analyses indicated that this similarity primarily stems from initial assortative mating, not from convergence of behaviors over time.

Conclusions:

• Observed similarity in cooperative and generous behaviors within couples is largely attributable to initial mate choice.
• This supports the hypothesis that cooperative traits play a role in assortative mating.
• The findings suggest that individuals select partners with similar prosocial tendencies, rather than developing them in unison after pairing.