The reality is that about 50% or maybe as high as 80% of men are not attractive as sex partners to women who are able to have many choices. And young women are

The reality is that about 50% or maybe as high as 80% of men are not attractive as sex partners to women who are able to have many choices. And young women are attractive to men of all ages... That is, the top 20% of men are the ones that are most desirable(however defined) . In the past the desire to have kids(and the result of needing the man to stick around), and the shame of being considered a slut if a woman's slept with many men, kept much of this in check.