On the Origin of Species

Charles Darwin's On the Origin of Species, published 24 November 1859, is a seminal work of scientific literature considered to be the foundation of evolutionary biology. Its full title was On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. For the sixth edition of 1872, the short title was changed to The Origin of Species. Darwin's book introduced the theory that populations evolve over the course of generations through a process of natural selection, and presented a body of evidence that the diversity of life arose through a branching pattern of evolution and common descent. He included evidence that he had accumulated on the voyage of the Beagle in the 1830s, and his subsequent findings from research, correspondence, and experimentation.

Various evolutionary ideas had already been proposed to explain new findings in biology. There was growing support for such ideas among dissident anatomists and the general public, but during the first half of the 19th century the English scientific establishment was closely tied to the Church of England, while science was part of natural theology. Ideas about the transmutation of species were controversial as they conflicted with the beliefs that species were unchanging parts of a designed hierarchy and that humans were unique, unrelated to animals. The political and theological implications were intensely debated, but transmutation was not accepted by the scientific mainstream.