Conrad Hal Waddington (1905-1975)


Conrad Hal Waddington was a developmental biologist and geneticist. Born in 1905, he went to Sidney Sussex College, Cambridge to read Natural Sciences, and was awarded a First in Geology in 1926 (having been introduced to the subject by Gregory, son of geneticist William Bateson). Waddington remained in Cambridge, engaging in philosophy, modern art and morris dancing, but then began reading the work of Hans Spemann, the German developmental biologist who discovered the embryonic ‘organiser’. In 1930 he visited Dame Honor Fell in the Strangeways Laboratory to ask whether Spemann’s work on amphibian embryos might be repeated in chicks, and this meeting was enough to persuade him to devote himself to embryology. He became a demonstrator in the Zoology Department, visited Spemann himself for six months, and in 1936 was elected (with support from C. P. Snow) a Fellow of Christ’s. He failed to persuade the College to have Walter Gropius design a new building, but otherwise this was one of the most successful and stimulating periods of Waddington’s life. He was able to demonstrate that induction did indeed occur in the chick embryo, and he embarked on a search, in collaboration with Joseph and Dorothy Needham, for the inductive molecule itself. Although the search was doomed to failure, he was awarded the Albert Brachet Prize for embryology in 1936 (a prize awarded to the President of Christ's, Professor Martin Johnson fifty-three year later!). In fact, the nature of the inducing factor was eventually discovered in the 1990s.

After the war, Waddington was offered the Chair of Genetics in Edinburgh. His Department grew and flourished, and he solved the problem of housing his new staff by persuading the Agricultural Research Council, who funded his work, to rent a large country house just outside the city. Run along Cambridge college lines, one of the occupants of Mortonhall House was Anne McLaren, later to become a Fellow Commoner of Christ’s.

It was in Edinburgh that Waddington did the work for which he is best known, in which he introduced the word ‘epigenetics’ and the concept of the epigenetic landscape. Waddington’s original definition of epigenesis referred to changes in the state of cell differentiation during development, and the way in which cell fates become restricted as development proceeds. The epigenetic landscape provided a visual description of this process, with cells, visualized as balls, rolling down a series of valleys to a position of minimum energy. The concept remains valuable, even though epigenetics has changed its definition, and now refers specifically to heritable traits that do not involve changes in DNA sequence.

In the course of his career, Waddington was elected a Fellow of the Royal Society and of the Royal Society of Edinburgh, and became a CBE in 1958. He died in 1975 at the age of 69.

Further reading: Biographical Memoirs of Fellows of the Royal Society, Vol. 23, (Nov., 1977), pp. 575-622.