Charles Robert Darwin (1809 – 1882) was an English naturalist who developed theories of the evolution of living things. After graduation from Cambridge, and being uncertain of a career path, Darwin was offered the role of companion to the Captain on the Royal Naval ship HMS Beagle (as the English class system made it inappropriate for the Captain to socialise with his crew!) Darwin acted as an additional naturalist for the voyage (a role that otherwise fell to the ship's doctor).
Darwin's father was a wealthy doctor, but expected his sons to take up a profession. Darwin originally intended to also be a doctor (studying in Edinburgh) but did not think he was suitable for such work (at a time when surgery was carried out without any anaesthetic). He was expected to become a clergyman after Cambridge, which would have provided a comfortable living with plenty of free time for following interests, but although still a Christian at that time (he later lost faith in a personal, loving God) felt he could not agree to some aspects of the Church of England doctrine (the so-called thirty-nine Articles of Religion) that he would have had to claim to accept for ordination.
"To him science was obviously not a 'profession', not even a way toward recognition and fame. It was a necessity to sustain his mind, just as the food he ate and the air he breathed were necessities for his body."
Theodosius Dobzhansky
Darwin made extensive observations (and collections) of geology and living things as the Beagle travelled around South America surveying the coasts, to the Galapagos islands and then on to circumnavigate the world. As well as writing (later publishing) a volume of his observations, he started a notebook considering the 'modification' of living things that later led to his evolutionary ideas.
Darwin sent scientific communications and specimens back to England (by other boats) when opportunities allowed. The voyage of the Beagle lasted almost five years, and by the time Darwin returned to England he had established himself as a competent scientist. Although this vocation did not provide any automatic income, Darwin's father was happy to support his son to be an amateur scientist and scholar as he clearly had a sense of purpose, was industrious, and was respected for his work. (It could be said that Darwin never had a 'proper job' in his life.)
Darwin developed a theory of evolution by 'natural selection', in parallel to Alfred Russel Wallace arriving at the same basic theory (their work was first presented to the same scientific meeting), which Darwin then set out in detail in "one long argument" in 'The Origin of Species' – arguably one of the most influential science books of all time – and in other books such as his 'Descent of Man' (which, despite the title, was mostly about other species).
Whilst some specific suggestions in Darwin's work have been superceeded by later research, the basic theory of natural selection is foundational to modern biology; and its integration with ideas from genetics and the use of statistical analysis provided what is sometimes known as neo-darwinism or the modern synthesis. It has been argued that nothing in modern biology makes sense without being considered in terms of natural selection.
In one sense, Darwin reflects the stereotype of the lone scientist. Darwin worked alone in his study at home, both in his scholarship and in carrying out varous anatomical studies and botanical experiments (such as testing conditions that effected the viability of seeds), and he limited his attendance at scientific meetings. However, Darwin built a network of correspondents internationally, and his books reflect (and acknowledge) his success in persuading many other scientists (and others such as gardeners, pigeon fanciers, farmers…) to provide him with observations and samples, and even in carrying out small experiments for him.
