Since hypergamy is an instinct, it makes sense that men would have their own related instincts. Since women are always looking for someone better, men cannot form lasting relationships horizontally, or by dating "up", only by dating "down".

Once again, all the fault is being laid at the feet of men, who are told it is their threatened masculinity that is to blame, and not a rational (even instinctual) response to women's hypergamous natures.

The Telegraph: Men 'feel threatened by intelligent women'
http://www.telegraph.co.uk/men/thinking-man/11945184/Men-feel-threatened-by-intelligent-women.html

JDBTv: Men Are "Threatened" By Intelligent Women?
https://www.youtube.com/watch?v=YKZ0PHb5mXc

Intro/Outro Song: "Earthy Crust" by Jingle Punks. Courtesy of the YouTube Audio Library.