Dating at age 15
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".
But here are some general guidelines from my experience: 1. What is quite different these days is that you are almost as likely to be questioned by your peers, the parents of your children’s friends, They will say: “These are different times. Once you are confident your son or daughter has met these standards, sit them down, let them know how much you admire who they are and who they’re becoming.
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.
However, human males tend to have more parental investment compared to mammal males (although females still tend to have more parental investment).
There are also social theories for age differences in relationships as well as suggested reasons for 'alternative' age-hypogamous relationships.
Age-disparity 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. Relationships with age disparity of all kinds have been observed with both men and women as the older or younger partner.
In all 37 cultures it was found that males preferred females younger than themselves and females preferred males older than themselves.