What is the title of Charles Darwin's famous book on evolution?

Charles Darwin’s famous book on evolution is On the Origin of Species. Its full first-edition title was On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life.

Published in London on 24 November 1859, the book argued that species are not fixed and that natural selection can drive evolutionary change. Darwin supported the argument with observations from geology, biogeography, breeding, anatomy and his voyage on HMS Beagle.

The book did not focus primarily on human evolution; Darwin treated that subject more directly in The Descent of Man, published in 1871. The Origin instead presented a broad explanation for the diversity and adaptation of living organisms through descent with modification.

The title was shortened in common use, and later editions changed it slightly. The sixth edition, published in 1872, dropped “On” and was titled The Origin of Species. The Variation of Animals and Plants under Domestication and The Voyage of the Beagle were also Darwin works, but neither is his principal book introducing natural selection.