Peter Medawar, born in 1915 in Brazil, was a British Biologist whose work on graft rejection and the discovery of an acquired immune tolerance was fundamental to the way that we understand science today.
Medawar's research at Oxford was on tissue culture, the regeneration of peripheral nerves and the mathematical analysis of the changes of shape of organisms that occur during this development. During the early stages of the Second World War he was asked by the Medical Research Council to investigate why it is that skin taken from one human being will not form a permanent graft on the skin of another person, and this work enabled him to establish theorems of transplantation immunity which formed the basis of his further work on this subject. When he moved to Birmingham in 1947 he continued to work on it, in collaboration with R. Billingham, and together they studied there problems of pigmentation and skin grafting in cattle, and the use of skin grafting to distinguish between monozygotic and dizygotic twins in cattle. In this work they took into consideration the work of R. D. Owen and concluded that the phenomenon that they called «actively acquired tolerance» of homografts could be artificially reproduced. For this earlier work on transplantation and growth, Medawar was elected a Fellow of the Royal Society, London. When he moved to London in 1951, Medawar continued to work with R. Billingham and L. Brent, on this phenomenon of tolerance, and his detailed analysis of it occupied him for several years. He also carried out other researches into transplantation immunity.
Among his achievements Peter Medawar was awarded the Royal Medal by The Royal Society of London in 1959, the Nobel Prize in 1960, was knighted in 1965, and appointed to the Order of Merit in 1981.
Peter Medawar died on October 2, 1987 and his work has been the basis of much scientific research ever since.