R. A. Fisher, or Ronald A. Fisher, was a British statistician and geneticist born in 1890. He is best known for his pioneering work in the field of statistics, particularly in the development of methods for experimental design and analysis of variance. Fisher's contributions laid the groundwork for modern statistical science and he is often referred to as one of the founders of modern statistics. In addition to his statistical work, Fisher made significant contributions to the field of population genetics. He introduced the concept of the Fisherian runaway in sexual selection and helped to integrate Mendelian genetics with Darwinian evolution. His influential book, "The Genetical Theory of Natural Selection," published in 1930, remains a key text in evolutionary biology.