Darwin's explanation of races by means of sexual selection

► Darwin provided a great deal of evidence for sexual selection in nonhumans. ► Much of that evidence was lacking for humans, and human cases differed from nonhuman. ► Darwin's argument for the origin of human races was (atypically) poor. ► Explaining race does not appear to be his main reason for taking up sexual selection. ► Darwin's reasons for discussing sexual selection in the Descent of Man are unclear.