Sir **Ronald Aylmer Fisher** (London, 17 February 1890 – Adelaide (Australia), July 19, 1962) was a British scientist in the field of statistics, theory of evolution and genetics. He put together with Sewall Wright and j.b.s. Haldane , the base of the population geneticsthat would culminate in the modern synthesis of evolutionary biology.

Fisher was born in London on 17 February 1890. He began his studies of mathematics and astronomy in Cambridge in 1909 and graduated with a degree in mathematics andphysics in 1912. In april of that year he published an article on what is now the "method of the greatest plausibility" (maximum likelihood) is called. He corresponded about it with W.S. Gosset, now also known under the pseudonym "Student", and came to the understanding that a clear distinction should be made between the sample and the populationthere.

Fisher introduced what is now called analysis of variance and the method of "randomization" in the study of design (experimental design).

Fisher worked after graduation only months as statistician at the firm "Mercantile and General Investment" in London. When he was in 1914 at the outbreak of the first world war in the army wanted, he was rejected because of his poor eyesight.

He was a teacher of mathematics and physics at several schools, two courses were offered to him in 1919, a by Karl Pearson, whose attention he had drawn, as head ofstatistics at the research station and a Galton as statistician at the Rothamsted agricultural research station in Harpenden. Fisher accepted the last position and worked there until he was appointed in 1933 as a successor of Pearson, who retired, as Professor of eugenics at University College London. In 1943, he was appointed Professor of geneticsin Cambridge.

Fisher received the Darwin MedalIn 1948. He was knighted In 1952. In 1955 he was awarded the Copley Medal. Sir Ronald Aylmer Fisher went with retirement in 1957, but remained two more years working in Cambridge. In 1958, he was awarded the Darwin-Wallace Medal by the Linnean Society of London. In 1959 he moved to Australia, where the last three years of his life he worked at the Department of mathematical statistics of the Commonwealth Scientific and Industrial Research Organisation.