Evolutionary psychologist Satoshi Kanazawa published in 2010 a controversial study into intelligence which, among other claims, suggested that IQ scores in men correlated positively with attitudinal preferences for sexual exclusivity, while no correlation between the two variables was present in women. However, as has been noted by Kanazawa himself, attitudinal preferences do not necessarily parallel behavioral preferrences, and there is even some data saying that IQ scores correlate negatively with marital sexual fidelity, especially in women.

Girls who had been younger than ~5 years of age during their parents’ divorce, had more sex partners and experienced puberty earlier than their older sisters, who had experienced the divorce at a more advanced age.

Church-attending women score lower on promiscuity than other women, while men appear to lack this correlation.