The Descent of Man, and Selection in Relation to Sex is a seminal book written by Charles Darwin, first published in 1871. It represents Darwin's application of his evolutionary theory, as outlined in his earlier work On the Origin of Species (1859), to the origins and development of humankind. The book explores human evolution from lower forms of life, emphasizing that humans share a common ancestry with other species, and challenges prevailing notions of divine creation by proposing natural processes as the mechanism for human development.
Darwin began writing The Descent of Man in 1868, twelve years after the publication of On the Origin of Species, during which he had deliberately avoided directly addressing human evolution to mitigate controversy. The book was published on February 24, 1871, by John Murray, the same publisher who handled Darwin's previous works. It was released in two volumes, with a total of 423 pages in the first edition. A second edition followed in 1874, with revisions and additions, including a preface where Darwin reflected on the "fiery ordeal" the book had endured amid public debate. The full title underscores the dual focus: the evolutionary descent of humans and the role of sexual selection in biological adaptation.
The manuscript was carefully edited for sensitivity. Darwin sent chapters to his daughter Henrietta Darwin to ensure no damaging inferences could be drawn, and he consulted his wife Emma Darwin for advice. The zoological illustrations were provided by T. W. Wood, enhancing the scientific presentation of anatomical comparisons.
The Descent of Man is divided into two main parts. The first part addresses the descent of humans, arguing that humankind evolved through natural selection from ancestral primates, sharing a common progenitor with apes. Darwin poses and answers key questions: Do humans descend from a common ancestor with other animals? How did this evolution occur? He asserts that traits like intelligence, moral sense, and social instincts developed gradually through natural selection, rather than being unique divine endowments.
The second part delves into sexual selection, a concept Darwin distinguishes from natural selection. Sexual selection explains traits that enhance reproductive success, such as elaborate plumage in birds or human physical differences between sexes. Darwin applies this to humans, discussing differences between males and females, and variations among human races. He concludes that all humans belong to a single species, with racial differences arising from sexual selection rather than separate evolutionary lineages. The book also touches on evolutionary psychology, ethics, musicology, and the societal implications of evolution.
The word "evolution" appears for the first time in any of Darwin's works on page 2 of the first volume, marking a shift in terminology. The final chapter applies sexual selection to humans and ends with a famous peroration on humanity's "lowly origin," emphasizing empathy for all life forms.
Published during the Victorian era, The Descent of Man built on the groundwork of On the Origin of Species but directly confronted human origins, a topic fraught with religious and social implications. It followed Thomas Huxley's 1863 book Evidence as to Man's Place in Nature, which had already introduced human evolution ideas. Darwin's work was influenced by contemporary anthropology, including debates on racial hierarchies and colonialism, though he rejected polygenism (separate origins for races) in favor of monogenism.
The book's reception was less explosive than that of On the Origin of Species, as evolutionary ideas had gained some acceptance by 1871. However, it sparked controversy, particularly over its implications for gender roles, racial differences, and morality. Critics, including religious figures, decried it as undermining human dignity, while supporters like Thomas Huxley and Alfred Russel Wallace praised its scientific rigor. Over time, it has been annotated and reissued, with a notable 2024 edition from Princeton University Press providing modern commentary.
Key facts include: the first edition sold about 4,500 copies rapidly; it was translated into multiple languages soon after; and Darwin's health issues delayed its completion. The book remains foundational in evolutionary biology, influencing fields like anthropology and psychology.
This response draws from reliable historical and scholarly sources, including: