BEHAVIORAL AND BRAIN SCIENCES (1992)15,75-133 Printed in the United States of America Age preferences in mates reflect sex differences in human reproductive strategies Douglas T.Kenrick Department of Psychology,Arizona State University,Tempe,AZ 852871 Electronlc mall:atdtk@asuacad.bitnet Richard C.Keefe Department of Behavioral Science,Scottsdale College,Scottsdale,AZ 85256 Electronlc mall:keefe@scc.bitnet Abstract:The finding that women are attracted to men older than themselves whereas men are attracted to relatively younger women has been explained by social psychologists in terms of economic exchange rooted in traditional sex-role norms.An alternative evolutionary model suggests that males and females follow different reproductive strategies,and predicts a more complex relationship between gender and age preferences.In particular,males'preferences for relatively younger females should be minimal during early mating years,but should become more pronounced as the male gets older.Young females are expected to prefer somewhat older males during their early years and to change less as they age.We briefly review relevant theory and present results of six studies testing this prediction.Study I finds support for this gender-differentiated prediction in age preferences expressed in personal advertisements.Study 2 supports the prediction with marriage statistics from two U.S.cities.Study 3 examines the cross- generational robustness of the phenomenon,and finds the same pattern in marriage statistics from 1923.Study 4 replicates Study 1 using matrimonial advertisements from two European countries,and from India.Study 5 finds a consistent pattern in marriages recorded from 1913 through 1939 on a small island in the Philippines.Study 6 reveals the same pattern in singles advertisements placed by financially successful American women and men.We consider the limitations of previous normative and evolutionary explanations of age preferences and discuss the advantages of expanding previous models to include the life history perspective. Keywords:attraction;ethological theory;evolution;gender differences;life history strategies;mate selection;sexual selection; similarity;social exchange 1.Introduction One reason is that social psychologists have generated a number of empirical findings that could be par- In his 1908 Social psychology,William McDougall ex- simoniously explained within an evolutionary framework. plained human heterosexual attraction in Darwinian Because social psychologists usually fail to consider the terms.In adopting an evolutionary perspective, role that evolutionary pressures might have played in MeDougall followed William James (1890),whom human heterosexual attraction,however,many of these McDougall replaced at Harvard.The evolutionary per- findings have been viewed as anomalies(Kenrick Trost spective adopted by these early functionalists was re- 1989).Another reason is that evolutionary biologists lose jected by psychologists who entered the field after the a valuable source of data when they ignore the social 1920s.Recent research,however,indicates that evolu- psychological literature,which has produced an abun- tionary models might be quite useful for explaining cer- dance of findings with implications for evolutionary mod- tain aspects of human social behavior (e.g.,Buss 1989; els (Kenrick Trost 1987).A combination of the two Daly Wilson 1988a).The ultimate perspective ofevolu- literatures could lead to new hypotheses that would not tionary theory may be particularly pertinent to reproduc- follow from either perspective in isolation. tive behavior,which is arguably the first line of evolution- In this target article,we consider a phenomenon that ary pressure (Barash 1982;Daly Wilson 1983). has been addressed by both social psychologists and Differential reproductive success is,after all,at the heart evolutionary biologists,but which has not been fully of natural selection. explored by either.A number of social psychological Although social psychologists and evolutionary biolo- studies have indicated a sex difference in preferred age of gists have mutual interests in reproductive behavior, mates.We argue here that this sex difference is not well they have,historically,shared little theory and research explained by traditional social psychological models.An with one another.This is unfortunate for several reasons. alternative evolutionary explanation can encompass sev- @1992 Cambridge University Press 0140-525X/92$5.00+.00 75