On the Origin of Species by Means of Natural Selection with a subtitle or the preservation of favoured races in the struggle for life was published by John Murray on 24 November 1859. Aimed at a general audience, the book sold out its entire 1,500 copy print run immediately, and 3,000 copies were reprinted in a little over a month.

The argument of the book was based on four central propositions:

  • Selective breeding, or artificial selection, can impact the form of plants and animals in a very short space of time. What of the impact over millions of generations?
  • The pressures of population growth and the scarcity of available resources provoke a natural form of selective breeding, as species struggle to survive.
  • Changes in the physical environment alter the nature of this competitive situation. Features that are advantageous to the new conditions will be favoured in the selection process.
  • All species have variation between individuals. Different variations will be favoured by different environments.

These new and controversial ideas prompted the up and coming biologist Thomas Huxley to write that he was “sharpening up my claws and beak in readiness” for the fight expected to follow.