The Descent of Man, and Selection in Relation to Sex

Lore & Background

Darwin wrote the book sending chapters to his daughter Henrietta for editing to ensure damaging inferences could not be drawn, and also took advice from his wife Emma. The zoological illustrator T. W. Wood drew many of the figures. Darwin's name created demand, but the ideas were old news; he found it 'proof of the increasing liberality of England' that everyone was talking about it without being shocked. Darwin and some of his children edited many revised editions. Initially he offered Wallace the work of assisting him, but when Emma found out, she had the task given to their son George, so Darwin had to write apologetically to Wallace. Huxley assisted with an update on ape-brain inheritance. This has been the edition most commonly reprinted after Darwin's death and to the present day. In the introduction, Darwin states the sole object is to consider whether man is descended from some pre-existing form, the manner of his development, and the value of differences between the so-called races of man. He argues for evolution of human beings by outlining similarities to other animals in body structure, embryology, and rudimentary organs. He then argues for similarity of mental characteristics, asserting that human character traits and mental characteristics are inherited like physical traits, and that the difference in mind between man and higher animals is one of degree and not of kind.

Reader's Guide

The Descent of Man is significant for extending Darwin's theory of evolution to humans, a step he had largely avoided in On the Origin of Species. It introduced the concept of sexual selection as a distinct mechanism alongside natural selection. The book also engaged with what later became known as social Darwinism and eugenics, though Darwin's own views were cautious: he noted that natural selection seemed no longer to act on civilised communities as it did on others, and he argued that the instinct of sympathy compelled humans to aid the weak, even if that had 'undoubtedly bad effects' on the race. He did not advocate coercive eugenics, but rather hoped that the weak might refrain from marriage. The book's legacy includes its influence on evolutionary psychology, ethics, and musicology, and its role in shaping debates about human races and sexes.

Did You Know?

• Darwin sent chapters to his daughter Henrietta for editing to prevent damaging inferences.