Six editions of On the Origin of Species were published during Darwin’s lifetime. The first edition appeared in 1859, and Darwin revised the book repeatedly as he answered objections, incorporated new arguments, and refined his presentation of natural selection.
The third edition, published in 1861, added an historical sketch of ideas about species. The fourth edition followed in 1866, while the fifth edition appeared in 1869 and introduced the phrase “survival of the fittest,” borrowed from Herbert Spencer. Darwin substantially revised the sixth edition in response to criticism, including objections raised by George Jackson Mivart.
The sixth edition was published in 1872 and became Darwin’s final edition. It also dropped “On” from the beginning of the title, so it was titled The Origin of Species. The six editions were not identical reprints: Darwin made cumulative changes throughout them, making the publication history important for understanding how his argument developed.