The original "big idea" book that changed natural science and transformed humanity's understanding of their place in the world--and remains controversial to this day. First published in 1859, On the Origin of Species introduced Charles Darwin's theory of natural selection to the world and, by extension, the role of evolution in natural biology and species development. By inferring through observation that species evolved over an immense amount of time, Darwin was able to articulate the basis of ideas like common descent, the struggle for survival, and inherited variance. Manifold and deeply destabilizing to their 19th century audience, the implications of natural selection reverberated across religion, philosophy, the liberal arts, and if course the scientific community. Drawn from years of observations and written for a non-scientific audience, On the Origin of Species is a classic that truly changed the world.