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 (generally males) over the parental investment of the higher investing sex (generally females) who will be more selective in their mate choice.
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 34% of women over 39 years old were dating younger men.
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 ...
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 (on average 4.5 years older), but they accept females considerably younger than their own age (on average 10 years younger).
The rational choice model suggests that people look for partners who can provide for them in their life (bread-winners); as men traditionally earn more as they get older, women will therefore prefer older men.
One of the concerns of relationships with age disparities in some cultures is a perceived difference between people of different age ranges.
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.
Buss attributed the young age preference for females to the cues that youth has.
A study released in 2003 by the United Kingdom's Office for National Statistics concluded that the proportion of women in England and Wales marrying younger men rose from 15% to 26% between 19.