According to Wikipedia:
"Charles Darwin's On the Origin of Species (published 1859) is a seminal work in scientific literature and arguably the pivotal work in evolutionary biology. The book's full title is On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. It introduced the theory that populations evolve over the course of generations through a process of natural selection. It was controversial because it contradicted religious beliefs which underlay the then current theories of biology. Darwin's book was the culmination of evidence he had accumulated on the voyage of the Beagle in the 1830s and expanded through continuing investigations and experiments since his return.
"The book is readable even for the non-specialist and attracted widespread interest on publication. The book was controversial, and generated much discussion on scientific, philosophical, and religious grounds. The scientific theory of evolution has itself evolved since Darwin first presented it, but natural selection remains the most widely accepted scientific model of how species evolve. The at-times bitter creation-evolution controversy continues to this day."
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