Charles Robert Darwin, (12 February 1809 – 19 April 1882) was an English naturalist, geologist and biologist, best known for his contributions to the science of evolution. His proposition that all species of life have descended over time from common ancestors is now widely accepted and considered a foundational concept in science.

In a joint publication with Alfred Russel Wallace, he introduced his scientific theory that this branching pattern of evolution resulted from a process that he called natural selection, in which the struggle for existence has a similar effect to the artificial selection involved in selective breeding.

Darwin was born into a well-connected family in Shrewsbury, whose members included prominent writers, entrepreneurs and intellectuals. Having begun studies in medicine, in 1831 Darwin took a position on a scientific expedition. Over five years he travelled the world on the ship HMS Beagle. During this time, Darwin was exposed to a huge variety of geological features and plant and animal life.

On his return to London in 1836, Darwin began systematically exploring the mechanisms through which this variety was created. He was influenced by the ideas of Thomas Malthus and suggested that those organisms best suited to a particular environment were more likely to reproduce. This has become known in popular culture as the ‘survival of the fittest’. Over time, this would lead to change and variation between species.

Darwin developed his theories of evolution over two decades. He did not publish them until 1858, when he discovered that another naturalist, Alfred Russel Wallace, had developed similar ideas. In 1859 Darwin published On the Origin of Species by Means of Natural Selection. The book immediately became controversial. Its implications for the traditional Christian view of creation were immense. It suggested that life had evolved over a far greater timespan than biblical accounts. It also suggested that humans were another form of animal life, rather than a divine creation. Darwin suffered from chronic illness all his life. There is still speculation about whether his symptoms were the type of nervous condition, relating to his concerns over the implications of his theories.

Darwin continued to publish books about human and animal revolution. His theories became immensely influential within biological sciences. His theories were also applied to social questions. Others used his ideas in developing theories such as eugenics and sciences of racial difference. There is continued debate about the connections that can be drawn between Darwin’s own ideas and the uses to they were put by others.