Who proposed the theory of evolution by natural selection?

Charles Darwin proposed the theory of evolution by natural selection. His explanation held that individuals vary, some of those differences are inherited, and organisms with advantageous traits are more likely to survive and reproduce.

Darwin developed the idea after studying fossils, living species, domesticated animals, and the geographical distribution of organisms. His five-year voyage on HMS Beagle, from 1831 to 1836, supplied important observations, but he spent more than two decades developing and testing the theory before publishing it.

Darwin first presented the theory publicly in a joint 1858 paper with Alfred Russel Wallace, who had independently arrived at a similar explanation. Darwin then gave the theory its fullest treatment in On the Origin of Species, published in 1859. Wallace was therefore a co-discoverer of natural selection, but Darwin is the standard single answer to this quiz question because of his extensive research and influential book.

Natural selection is the mechanism; evolution is the broader process of inherited change in populations over generations.