Sheppard, P. M. (Philip MacDonald)

Philip Macdonald Sheppard (1921-1976) was a geneticist whose primary interests included human and population genetics, evolution, medicine, and certain aspects of ecology and ecological genetics. He was especially concerned with polymorphism, mimicry, blood groups and disease, and the genetics of species differences (See Series II, Subject Files under Biographical Information). His important contributions to genetics include: his studies on natural selection in the polymorphic land snail ( Cepaea nemoralis ) in collaboration with A. J. Cain; his joint studies with Cyril Clarke on Rhesus hemolytic disease in newborn babies which led to the development of a preventive treatment; and the genetics and evolution of mimicry in butterflies.

Philip Macdonald Sheppard was born on 27 July 1921 in Marlborough, Wiltshire, England to George Sheppard, a schoolmaster, and Alison Macdonald. He was educated at Marlborough College from 1935 to 1939, served with the Royal Air Force Volunteer Reserve from 1940 to 1945, and was a prisoner-of-war from 1942 to 1945. He studied at Worcester College, Oxford University from 1946 to 1948. In 1948, he received a second class honours degree in Zoology, and was subsequently awarded the Christopher Welch Research Scholarship. Under E. B. Ford's guidance, he studied for the D.Phil. and obtained the degree in 1951. His thesis was entitled "Genetic and Evolutionary Problems in wild populations of the Lepidoptera and other forms."

Sheppard was a Junior Research Officer in the Department of Zoology at Oxford from 1951 to 1956. In 1954, he was awarded a fellowship by the Rockefeller Foundation which enabled him to work for one year with Theodosius Dobzhansky at Columbia University, New York. He was appointed Senior Lecturer in Genetics in the Department of Zoology at the University of Liverpool in 1956, was promoted to Reader in Genetics in 1959, and, in 1963, became the first Professor of Genetics at Liverpool. He continued in that position until his death.

An excellent statistician and geneticist, "[Sheppard's] genius lay in the experimental approach, whether it was with butterflies, moths, snails or man." 1 His research on the moth Panaxia dominula (the Scarlet Tiger), and Cepaea nemoralis (the land snail) showed the effects of various kinds of natural selection in controlling the genetic composition of wild populations. His work on Panaxia, which continued the work begun by R.A. Fisher and E.B. Ford, "was extremely influential in establishing the view that natural selection was the all-powerful process in generating evolutionary change." 2

Much of Sheppard's research was done in collaboration with other scientists. With Cyril Clarke, he carried out his work on the genetics of butterfly mimicry and the prevention of rhesus hemolytic disease. Their work on mimicry in Papilio dardanus and P. memnon, and Heliconius melpomene and H. erato led to the "discovery of 'supergenes,' tightly linked blocks of functionally independent genes, all controlling different aspects of the mimetic pattern." In an effort to demonstrate that natural selection was active in human populations, "Clarke and Sheppard investigated the correlations of blood groups with disease... Believing also that the rhesus blood groups were controlled by a supergene similar to that found in mimetic butterflies, they then turned their attention to the chief form of natural selection known to work on these blood groups, hemolytic disease of the newborn. This led to an enduring advance in pediatrics: the prevention of this condition--a major cause of miscarriage, infant death, and brain damage--by injecting with rhesus antibody those mothers known to be at risk." 3

Research conducted with Cyril Clarke, R.B. McConnell, and David Price Evans included a project on sibship and antigen studies in duodenal ulcers, blood groups and secretion in carcinoma of the stomach, tylosis and carcinoma of the oesophagus, PTC tasting and thyroid diseases, serological study of mucosa cells, biochemical study of blood group substances, Klinefelter's syndrome, secretor character and sub-fertility, secretor character in gastric ulcers, secretor character in mitral stenosis, and other blood group systems in hemolytic disease of the newborn due to Rh incompatibility (See Series I, Cyril A. Clarke, Sept. 1958).

Sheppard also made important studies on the evolution of dominance, the genetics of industrial melanism in moths, particularly Biston betularia (the pepper moth), and heavy metal tolerance in plants, principally in Mimulus (monkey musk). He was invited by the World Health Organization to investigate the population genetics of insecticide-resistant mosquitos ( Aedes ) in Southeast Asia; this work was done in collaboration with W.W. Macdonald. His research also included the genetics of schizophrenia, anencephaly and spina bifida in humans. 4 With J.J.B. Gill, Sheppard examined the genetics of prostrate forms in broom ( Cytisus ).

His research on how natural selection works and its effect on the genetic constitution of organisms resulted in Natural Selection and Heredity (1958) and numerous other studies of butterflies, moths, snails and human medical genetics. Although initially uncomfortable in front in the lecture hall, Sheppard fashioned himself into a "first-class lecturer." He lectured at many institutions in Great Britain and in the United States. He was "an invited speaker at many conferences, a guest of the Australian Universities Vice-Chancellors' Committee in 1967, Visiting Professor of Genetics at Davis, California in 1968, and a Royal Society Leverhulme Visiting Professor in Brazil in 1971." 5 In 1973, Sheppard edited Practical Genetics, a book designed to aid instructors of genetics.

In 1966 and again in 1967, Sheppard excited public interest in genetics by organizing "a highly successful television series with Granada, compris[ed of] ten programmes on evolution. He devised the series and acted as adviser throughout, and his idea was that the programmes taken together should give a good general account of the theory of evolution, its origins and the modern evidence for its validity." 6

Though not an avid committee member, Sheppard served on several committees throughout his career. These include the Committee of the Genetical Society of Great Britain from 1953-55, the Aldabra Research Committee of the Royal Society, and on the Sub-Committee of the Research Grants Committee of the D.S.I.R. from 1964 to 1965. He also served on various committees of the University of Liverpool, "especially the Ness Gardens Management Committee,... the Fluoridation Committee of the Royal College of Physicians,...the University Grants Committee's Biological Sciences Sub-Committee, and on occasion in relation to committees of the World Health Organization." 7

Sheppard was elected a fellow of the Royal Society of London in 1965, and was awarded its Darwin Medal in 1974. In 1975, he received the Gold Medal for Zoology from the Linnaean Society, and, in recognition of his work with Cyril Clarke on rhesus factors, was made an Honorary Fellow of the Royal College of Physicians in the same year.

Sheppard died of acute leukemia in Liverpool on October 17, 1976. He was survived by his wife, Patricia Beatrice Lee, whom he had married in 1948, and by their three sons.

From the guide to the Philip M. Sheppard Papers, Bulk, 1940-1976, 1911-1983, (American Philosophical Society)