Happy 150th, "Descent of Man"

Charles Darwin’s book “The Descent of Man, and Selection in Relation to Sex,” was published on this day 150 years ago, by his British publisher John Murray. This was the first time Darwin used the word “evolution" in print. Darwin discusses natural selection in conjunction with his theory of how birds and animals choose mates. He applies principles of natural selection to humans, demonstrating our descent from earlier species. Our physical similarities with apes are attributed to common antecedent creatures, something that has been confirmed through DNA analysis. He also discusses topics like psychology, ethics, the races, and society. (He does not embrace what became known as Social Darwinism, nor racial polygeny.) The book was not as controversial as “Origin of Species,” published 12 years earlier, because people had already been debating Darwin’s ideas for a while, but it did elicit considerable discussion. Darwin soon followed up on ideas in “Descent” with his next book, “The Expression of Emotions in Man and Animals” (1872)--which, in turn, was one of the first books to be illustrated with photographs.