Conrad Hal Waddington

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Conrad Hal Waddington
Born November 8, 1905
Evesham, Worcestershire, England
Died September 26, 1975
Edinburgh, Scotland
Fields Developmental biology, Genetics, Paleontology
Institutions Cambridge University, Christ's College
University of Edinburgh
Alma mater Cambridge University
Known for Epigenetic landscape, canalisation, homeorhesis, genetic assimilation
Influences Alfred North Whitehead
Influenced Jean Piaget

Conrad Hal Waddington FRS FRSE (1905–1975) was a developmental biologist, paleontologist, geneticist, embryologist and philosopher who laid the foundations for systems biology. He had wide interests that included poetry and painting, as well as left-wing political leanings.[citation needed]

Contents

[edit] Life

Waddington was educated at Clifton College and Cambridge University, where he was a lecturer in zoology and a Fellow of Christ's College until 1942, where his friends included Walter Gropius, C. P. Snow, and J. D. Bernal.[1] His interests began with palaeontology but moved on to the heredity and development of living things. He also studied philosophy.

During World War II he was involved in operational research with the Royal Air Force and became scientific advisor to the Commander in Chief of Coastal Command from 1944 to 1945. After the war he became Professor of Animal Genetics at the University of Edinburgh. He would stay at Edinburgh for the rest of life. His personal papers are largely kept at the University of Edinburgh library.

Waddington was married twice. His first marriage produced a son, C. Jake Waddington, now professor of physics at the University of Minnesota, but ended in 1936. He then married Justin Blanco White, daughter of the writer Amber Reeves, with whom he had two daughters, noted mathematician Dusa McDuff and noted anthropologist Caroline Humphrey.[2]

In the early 1930s, Waddington and many other embryologists looked for the molecules that would induce the amphibian neural tube. The search was, of course, beyond the technology of that time, and most embryologists moved away from such deep problems. Waddington, however, came to the view that the answers to embryology lay in genetics, and in 1935 went to Thomas Hunt Morgan's Drosophila laboratory in California, even though this was a time when most embryologists felt that genes were unimportant and just played a role in minor phenomena such as eye colour.

In the late 30's, Waddington produced formal models about how gene regulatory products could generate developmental phenomena, showed how the mechanisms underpinning Drosophila development could be studied through a systematic analysis of mutations that affected developmental anatomy (this was the essence of the approach that won the 1995 Nobel prize in medicine for Christiane Nüsslein-Volhard and Eric F. Wieschaus) and wrote his first textbook of developmental epigenetics, a term that then meant the external manifestation of genetic activity.

Waddington also coined other essential concepts, such as canalisation, which refers to the ability of an organism to produce the same phenotype in various different environments. He also invented a mechanism called genetic assimilation which would allow an animal’s response to an environmental stress to become a fixed part of its developmental repertoire, and then went on to show that the mechanism would work. He thus demonstrated that the ideas of inheritance put forward by Jean-Baptiste Lamarck could, in principle at least, occur.

[edit] Epigenetic landscape

Waddington's epigenetic landscape is a metaphor for how gene regulation modulates development.[3] One is asked to imagine a number of marbles rolling down a hill towards a wall. The marbles will compete for the grooves on the slope, and come to rest at the lowest points. These points represent the eventual cell fates, that is, tissue types. This idea was actually based on experiment: Waddington found that one effect of mutation (which could modulate the epigenetic landscape was) was to affect how cells differentiated.

[edit] Waddington as organiser

Waddington was very active in advancing biology as a discipline. He contributed to a book on the role of the sciences in times of war, and helped set up several professional bodies representing biology as a discipline.

A remarkable number of his contemporary colleagues in Edinburgh became Fellows of the Royal Society during his time there, or shortly thereafter.[4]

Waddington was an old-fashioned intellectual who lived in both the arts and science milieus of the 1950s and wrote widely. His 1960 book "Behind Appearance; a Study Of The Relations Between Painting And The Natural Sciences In This Century" (MIT press) not only has wonderful pictures but is still worth reading.

Waddington was, without doubt, the most original and important thinker about developmental biology of the pre-molecular age and the medal of the British Society for Developmental Biology is named after him.

[edit] References

  1. ^ Robertson, Alan. 1977. Conrad Hal Waddington. 8 November 1905 — 26 September 1975. Biographical Memoirs of Fellows of the Royal Society 23, 575-622. Pp. 579-580.
  2. ^ Robertson, Alan. 1977. Conrad Hal Waddington. 8 November 1905 — 26 September 1975. Biographical Memoirs of Fellows of the Royal Society 23, 575-622. P. 578
  3. ^ Goldberg, A. D., Allis, C. D., & Bernstein, E. (2007). Epigenetics: A landscape takes shape. Cell, 128, 635-638.
  4. ^ Robertson, Alan. 1977. Conrad Hal Waddington. 8 November 1905 — 26 September 1975. Biographical Memoirs of Fellows of the Royal Society 23, 575-622. P. 585.

[edit] Selected works

[edit] Books

  • Waddington, C. H. (1940). Organisers & genes. Cambridge: Cambridge University Press.
  • Waddington, C. H. (1941). The Scientific Attitude, Pelican Books
  • Waddington, C. H. (1946). How animals develop. London : George Allen & Unwin Ltd.
  • Waddington, C. H. (1956). Principles of Embryology. London : George Allen & Unwin.
  • Waddington, C. H. (1957). The Strategy of the Genes. London : George Allen & Unwin.
  • Waddington, C. H. (1959). Biological organisation cellular and subcellular : proceedings of a Symposium. London: Pergamon Press.
  • Waddington, C. H. (1960). The ethical animal. London : George Allen & Unwin.
  • Waddington, C. H. (1961). The human evolutionary system. In: Michael Banton (Ed.), Darwinism and the Study of Society. London: Tavistock.
  • Waddington, C. H. (1966). Principles of development and differentiation. New York: Macmillan Company.
  • Waddington, C. H. (1966). New patterns in genetics and development. New York: Columbia University Press.
  • Waddington, C. H., ed. (1968-72). Towards a Theoretical Biology. 4 vols. Edinburgh: Edinburgh University Press.

[edit] Papers

  • Waddington, C. H. 1953. Genetic assimilation of an acquired character. Evolution 7: 118-126.
  • Waddington, C. H. 1956. Genetic assimilation of the bithorax phenotype. Evolution 10: 1-13.
  • Waddington, C. H. 1961. Genetic assimilation. Advances Genet. 10: 257-290.

[edit] External links

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