First published in 1871, The Descent of Man, and Selection in Relation to Sex sees Darwin apply his evolutionary theory to the human race, controversially placing apes in our family tree. The book covers a range of adjacent themes, including differences between different peoples, the dominance of women in mate choice, and the relevance of evolutionary theory to general society.
After the criticism of his On the Origin of Species, Darwin was apprehensive about the possible public reception of The Descent of Man. However, there was an immediate interest in the book, and it had to be reprinted within three weeks of publication, leading a relieved Darwin to remark that "Everybody is talking about it without being shocked".