while it might be tempting to think that the recent increase in the age of first reproduction among humans will reduce costly displays of fitness among young men (and make smart, sensitive young men more attractive to their peers), this is unlikely to have any quick impact. An evolutionary transformation like that would require a genetic difference between risk-takers and safe players, followed by many generations of selective pressure. Absent those factors, humans can count on adolescent boys doing stupid things for some time to come.
