Charles Darwin's theory of evolution made him one of the best known persons of all time. In his book called On the Origin of Species (published in 1859) Darwin explained biological change with the help of his theory.

Naturalist Charles Darwin was born in Shrewsbury, England, on February 12, 1809. In 1831, he embarked on a five-year survey voyage around the world on the HMS Beagle. His studies of specimens around the globe led him to formulate his theory of evolution and his views on the process of natural selection.

Darwin's exposure to specimens all over the globe raised important questions. Other naturalists believed that all species either came into being at the start of the world, or were created over the course of natural history. Darwin noticed similarities among species all over the globe, along with variations based on specific locations, leading him to believe that they had gradually evolved from common ancestors. He came to believe that species survived through natural selection.

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