Abstract
Sex differences in jealousy responses to sexual and emotional infidelity are robust in samples of heterosexual adults, especially in more gender egalitarian nations. However, investigations of when and how these differences develop have been scant. We applied two forced choice infidelity scenarios in a large community sample of high school students (age 16-19, N = 1266). In line with previous findings on adults using the forced choice paradigm, adolescent males found the sexual aspect of imagined infidelity more distressing than adolescent females did. Nevertheless, there was no effect of age on the jealousy responses, and age did not moderate the sex difference. There were neither any effects of three covariates (having had first sexual intercourse, being in a committed romantic relationship, and sociosexuality), neither as markers of pubertal maturation nor as psychosocial environmental stimuli. Future research needs to investigate even younger samples in order to specify at what age the sex difference in jealousy responses emerges.