Individuals prefer helping some people more that others when it comes to
finding a mate, and these preferences depend on whether long- or short-term mates are
considered. Study 1 (N = 108) examined three theoretical frameworks (inclusive fitness,
reciprocal altruism, and parental investment) for understanding why individuals would be
more willing to help some individuals find mates instead of others. College participants
reported how willing they were to help different types of individuals (e.g., sister, stranger)
find a mate. When considering willingness to help others find a long-term mate, people
preferred kin over nonkin, supporting an inclusive fitness model. However, when
considering willingness to help others find short-term mates, people preferred helping
people their own age, supporting a reciprocal altruism model. Study 2 (N = 143) replicated
this age-cohort effect. Although rates of willingness to help others find mates were
generally low, people were more likely to help others find a long-term mate than a shortterm
one.