Darwin's Descent of Man (1871)

©AMNH Library

The Descent of Man, published a dozen years after the Origin, tackles what Darwin knew would be the most controversial aspect of evolution by natural selection: humans, too? Darwin's response to what he called "the highest and most interesting problem for a naturalist" was clear. "Man," he writes, "with all his noble qualities...still bears in his bodily frame the indelible stamp of his lowly origin." That is, we share an ancestry with the other primates.

Darwin braced himself for a ferocious response--especially from the church. But other scientists, including Darwin's friend T. H. Huxley and the naturalist Alfred Russel Wallace, had already begun to write about human evolution, so the idea was no longer as shocking as Darwin had feared. The Descent had its critics, but the overall response was surprisingly mild. "I dined out three days last week," one of Darwin's friends told him, "and at every table heard evolution talked about as accepted fact, and the descent of man with calmness." Darwin was pleased--and relieved.