A modern account of sexual selection would run something like this.

Sexual selection in this species is based on the size of the male.

Sexual selection can be a kind of evolutionary arms race.

I am especially glad that you are turning your attention to sexual selection.

Recent social changes may have accelerated the pace of sexual selection.

Its behavior is studied in an effort to understand sexual selection, especially the topic of female choice.

Darwin turned his attention to sexual selection, writing to scientist friends for information.

This explains how the sexual selection of the species evolved, he said.

This is known as the handicap theory of sexual selection.

As a result of female choice, sexual selection is imposed on males.