Age disparity in sexual relationships
In sexual relationships, concepts of age disparity, including what defines an age disparity, have developed over time and vary among societies. Differences in age preferences for mates can stem from partner availability, gender roles, and evolutionary mating strategies, and age preferences in sexual partners may vary cross-culturally. There are also social theories for age differences in relationships as well as suggested reasons for "alternative" age-hypogamous relationships. Age-disparate relationships have been documented for most of recorded history and have been regarded with a wide range of attitudes dependent on sociocultural norms and legal systems.
Statistics (heterosexual)
Data in Australia and the United Kingdom show a similar pattern.Relationships with age disparities have been observed with both men and women as the older or younger partner. In various cultures, older men and younger women often seek one another for sexual or marital relationships. Older women sometimes date younger men as well, and in both cases wealth and apparent physical attractiveness are often relevant. Adolescent boys are generally sexually interested in adolescent girls and women somewhat older than they are. Older men also display an interest in women of their own age. However, research suggests that relationship patterns are more influenced by women's preferences than men's.
Most men marry women younger than they are, with the difference being between two and three years in Spain, the UK reporting the difference to be on average about three years, and the US, two and a half. The pattern was also confirmed for the rest of the world, with the gap being largest in Africa. However, the number of women marrying younger men is rising. A study released in 2003 by the UK's Office for National Statistics concluded that the proportion of women in England and Wales marrying younger men rose from 15% to 26% between 1963 and 1998. Another study also showed a higher divorce rate as the age difference rose for when either the woman was older or the man was older. A 2008 study, however, concluded that the difference is not significant.
In August 2010, Michael Dunn of the University of Wales Institute, Cardiff, completed and released the results of a study on age disparity in dating. Dunn concluded that "Not once across all ages and countries... did females show a preference for males significantly younger than male preferences for females" and that there was a "consistent cross-cultural preference by women for at least same-age or significantly older men". A 2003 AARP study reported that only 34% of women over 39 years old were dating younger men.
A 2011 study suggested that marriage of younger men by women is positively correlated with decreased longevity, particularly for the woman, though married individuals generally still have longer lifespans than singles.
Reasons for age disparity (heterosexual)
People enter into age-disparate relationships for complex and diverse reasons, and a 2021 review in the Journal of Family Theory and Review showed vast differences across contexts. Explanations for age disparity usually focus on either the rational choice model or the analysis of demographic trends in a society.The rational choice model suggests that people look for partners who can provide for them in their life ; as men earn more as they get older, their partners will therefore prefer older men. This factor is diminishing as more women enter the labor force. The demographic trends are concerned with the sex ratio in the society, the marriage squeeze, and migration patterns.
Another explanation concerns cultural values: the higher the value placed in having children, the higher the age gap will be. Yet Canadian researchers have found that age-disparate couples are less likely to have children than similarly aged ones. As people have chosen to marry later and remarriage becomes more common, the age differences between couples have increased as well.
In a Brown University study, it has been noted that the social structure of a country determines the age difference between spouses more than any other factor. One of the concerns of relationships with age disparities in some cultures is a perceived difference between people of different age ranges. These differences may be sexual, financial or social. Gender roles may complicate this even further. Socially, a society with a difference in wealth distribution between older and younger people may affect the dynamics of the relationship.
Although the "cougar" trend, in which older women date much younger men, is often portrayed in the media as a widespread and established facet of modern Western culture, at least one academic study has found the concept to be a "myth". A British psychological study published in Evolution and Human Behavior in 2010 concluded that men and women, in general, continued to follow traditional gender roles when searching for mates. The study found that, as supported by other academic studies, most men preferred younger, "attractive" women, while most women, of any age, preferred successful, established men their age or older. The study found very few instances of older women pursuing much younger men and vice versa. The study has been criticized, however, for limiting its results to online dating profiles, which are traditionally not used by those seeking older or younger partners, and for excluding the United States from the study.
Evolutionary perspective
Evolutionary approach to heterosexual age disparity in sexual relationships
The evolutionary approach, based on the theories of Charles Darwin, attempts to explain age disparity in sexual relationships in terms of natural selection and sexual selection. Within sexual selection, Darwin identified a further two mechanisms which are important factors in the evolution of sex differences : intrasexual selection and intersexual choice. Life history theory provides an explanation for the above mechanisms and strategies adopted by individuals, leading to age disparity in relationships. Life history theory posits that individuals have to divide energy and resources between activities and this is shaped by natural selection.Parental Investment Theory refers to the value that is placed on a potential mate based on reproductive potential and reproductive investment. The theory predicts that preferred mate choices have evolved to focus on reproductive potential and reproductive investment of members of the opposite sex. This theory predicts both intrasexual selection and intersexual choice due to differences in parental investment; typically there is competition among members of the lower investing sex over the parental investment of the higher investing sex who will be more selective in their mate choice. However, human males tend to have more parental investment than do other mammal males. Thus, both sexes will have to compete and be selective in mate choices. These two theories explain why natural and sexual selection acts slightly differently on the two sexes so that they display different preferences. For example, different age preferences may be a result of sex differences in mate values assigned to the partner's sex at those ages.
A study conducted by David Buss investigated sex differences in mate preferences in 37 cultures with 10,047 participants. In all 37 cultures it was found that males preferred females younger than themselves and females preferred males older than themselves. These age preferences were confirmed in marriage records with males marrying females younger than them. A more recent study has supported these findings, conducted by Schwarz and Hassebrauck. This study used 21,245 participants between 18 and 65 years of age who were not involved in a close relationship. As well as asking participants a number of questions on mate selection criteria, they also had to provide the oldest and youngest partner they would accept. It was found that for all ages males were willing to accept females that are slightly older than they are, but they accept females considerably younger than their own age. Females demonstrate a complementary pattern, being willing to accept older males and were also willing to accept males younger than themselves. This is somewhat different to our close evolutionary relatives: chimpanzees. Male chimpanzees tend to prefer older females than younger and it is suggested that specific cues of female mate value are very different to humans.
Male preference for younger females
attributed the male preference for younger females to certain youthful cues. In females, relative youth and apparent physical attractiveness demonstrated cues for fertility and high reproductive capacity. Buss stated the specific age preference of around 25 years implied that fertility was a stronger ultimate cause of mate preference than reproductive value as data suggested that fertility peaks in females around mid-20s. From a life history theory perspective, females that display these cues are judged to be more capable of reproductive investment. This notion of age preference due to peak fertility is supported by Kenrick, Keefe, Gabrielidis, and Cornelius's study, which found that although teenage males would accept a mate slightly younger than they are, there was a wider range of preference for ages above their own. Teenage males also report that their ideal mates would be several years older than they are.Buss and Schmitt stress that although long-term mating relationships are common for humans, there are both short-term and long-term mating relationships. Buss and Schmitt provided a Sexual Strategies Theory that describes the two sexes as having evolved distinct psychological mechanisms that underlie the strategies for short- and long-term mating. This theory is directly relevant and compatible with those two already mentioned, Life History and Parental Investment. Males tend to appear oriented towards short-term mating and this appears to solve a number of adaptive problems including using fewer resources to access a mate. Although there are a number of reproductive advantages to short-term mating, males still pursue long-term mates, and this is due to the possibility of monopolizing a female's lifetime reproductive resources. Consistent with findings, for both short-term and long-term mates, males prefer younger females.