On the Origin of Species is an 1859 scientific work by Charles Darwin explaining his theory of natural selection, which he arrived upon in the years since his Beagle expedition in the 1830s. Darwin argued that populations would grow if not for limited resources and, as a result, members of a species compete for these resources. Because of hereditary variety within a species, some members receive these resources and others do not. As a result, these members survive and proliferate, causing species to change and diverge over time.
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