Sir Gavin Rylands de Beer (1 November 1899 – 21 June 1972) was a British evolutionary embryologist, known for his work on heterochrony as recorded in his 1930 book Embryos and Ancestors. He was director of the Natural History Museum, London, president of the Linnean Society of London, and a winner of the Royal Society's Darwin Medal for his studies on evolution. Biography Born on 1 November 1899 in Malden, Surrey (now part of London), de Beer spent most of his childhood in France, where he was educated at the Parisian École Pascal. During this time, he also visited Switzerland, a country with which he remained fascinated for the rest of his life. His education continued at Harrow and Magdalen College, Oxford, where he graduated with a degree in zoology in 1921, after a pause to serve in the First World War in the Grenadier Guards and the Army Education Corps. In 1923 he was made a fellow of Merton College, Oxford, and began to teach at the university's zoology department. In 1938, he was made reader in embryology at University College, London. During the Second World War, he again served with the Grenadier Guards reaching the rank of temporary lieutenant colonel. He worked in intelligence, propaganda and psychological warfare. In 1940, he was elected as a Fellow of the Royal Society. In 1945, de Beer became professor of zoology and was, from 1946 to 1949, president of the Linnean Society. Then he was director of the British Museum (Natural History) (now the Natural History Museum), from 1950 until his retirement in 1960. He was knighted in 1954, and awarded the Darwin Medal of the Royal Society in 1957. In 1958, he delivered the British Academy's Master-Mind Lecture, on Charles Darwin. In 1961 he gave the Royal Society of London's Wilkins Lecture. After his retirement, de Beer moved to Switzerland and worked on several publications on Charles Darwin, including first publication of Darwin's manuscripts including his private notebooks, opening them to scholarship which became the "Darwin Industry". He also wrote his own seminal Atlas of Evolution and a series of books about Switzerland and the Alps. De Beer returned to England in 1971 and died at Alfriston, Sussex on 21 June 1972. Work De Beer's early work at Oxford was influenced by J. B. S. Haldane and by Julian Huxley and E. S. Goodrich (two of his teachers). His early