John Thoday
Encyclopedia
John Marion Thoday FRS (30 August 1916 - 25 August 2008) was a British geneticist
. He was the son of the botanist David Thoday
. He was Arthur Balfour Professor of Genetics
at Cambridge University between 1959 and 1983 and was elected a Fellow of the Royal Society in 1965.
Thoday was born in Chinley
, Derbyshire
, and educated at Bootham School
, York
, followed by University College of North Wales at Bangor
, and then Trinity College, Cambridge
. During World War II
he served in the RAF
as a photographic intelligence officer.
His research from 1947 has been largely concerned with the causes and functions of intraspecific genetic variation
, on the nature of continuous genetic variation and on the effects of selection on such variation. He has published an important thesis on the meaning of biological progress in evolution
and the role of genetic variation in determining long term fitness. He has pioneered a method for the location on chromosomes of genes
mediating continuous variation, and showed (contrary to accepted theory) that the genes at different loci affected the quantitative character in qualitatively different ways. He has pioneered experiments into disruptive selection
(selection in the same population for both extremes and against intermediates), and (again contrary to theoretical expectation), showed such selection could be extremely effective, increasing variance, establishing and maintaining polymorphisms
, and, if the selected individuals were allowed to choose their mates, dividing the population into two partially isolated parts, something which is a step towards speciation
.
Geneticist
A geneticist is a biologist who studies genetics, the science of genes, heredity, and variation of organisms. A geneticist can be employed as a researcher or lecturer. Some geneticists perform experiments and analyze data to interpret the inheritance of skills. A geneticist is also a Consultant or...
. He was the son of the botanist David Thoday
David Thoday
David Thoday FRS was a botanist. He was Harry Bolus professor of botany, University of Cape Town and later professor at the University College of North Wales 1923-1949. He was elected a Fellow of the Royal Society in 1942. His son was the geneticist John Thoday...
. He was Arthur Balfour Professor of Genetics
Arthur Balfour Professor of Genetics
The Arthur Balfour Professorship of Genetics is one of the senior professorships in genetics at the University of Cambridge, founded in 1912.The chair was endowed by Reginald Baliol Brett, 2nd Viscount Esher, according to whom the money was "placed in [his] hands" by an anonymous benefactor...
at Cambridge University between 1959 and 1983 and was elected a Fellow of the Royal Society in 1965.
Thoday was born in Chinley
Chinley
Chinley is a rural village in High Peak Borough, situated on the western edge of the Peak District National Park in Derbyshire, England, with a population of around 2000. Before the railway, the area was economically dominated by agriculture and quarrying. Three textile mills were established in...
, Derbyshire
Derbyshire
Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...
, and educated at Bootham School
Bootham School
Bootham School is an independent Quaker boarding school in the city of York in North Yorkshire, England. It was founded by the Religious Society of Friends in 1823. It is close to York Minster. The current headmaster is Jonathan Taylor. The school's motto Membra Sumus Corporis Magni means "We...
, York
York
York is a walled city, situated at the confluence of the Rivers Ouse and Foss in North Yorkshire, England. The city has a rich heritage and has provided the backdrop to major political events throughout much of its two millennia of existence...
, followed by University College of North Wales at Bangor
Bangor, Gwynedd
Bangor is a city in Gwynedd, north west Wales, and one of the smallest cities in Britain. It is a university city with a population of 13,725 at the 2001 census, not including around 10,000 students at Bangor University. Including nearby Menai Bridge on Anglesey, which does not however form part of...
, and then Trinity College, Cambridge
Trinity College, Cambridge
Trinity College is a constituent college of the University of Cambridge. Trinity has more members than any other college in Cambridge or Oxford, with around 700 undergraduates, 430 graduates, and over 170 Fellows...
. During World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
he served in the RAF
Royal Air Force
The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
as a photographic intelligence officer.
His research from 1947 has been largely concerned with the causes and functions of intraspecific genetic variation
Genetic variation
Genetic variation, variation in alleles of genes, occurs both within and among populations. Genetic variation is important because it provides the “raw material” for natural selection. Genetic variation is brought about by mutation, a change in a chemical structure of a gene. Polyploidy is an...
, on the nature of continuous genetic variation and on the effects of selection on such variation. He has published an important thesis on the meaning of biological progress in evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
and the role of genetic variation in determining long term fitness. He has pioneered a method for the location on chromosomes of genes
Gênes
Gênes is the name of a département of the First French Empire in present Italy, named after the city of Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa, and it was divided in the arrondissements of Genoa, Bobbio, Novi Ligure, Tortona and...
mediating continuous variation, and showed (contrary to accepted theory) that the genes at different loci affected the quantitative character in qualitatively different ways. He has pioneered experiments into disruptive selection
Disruptive selection
Disruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups...
(selection in the same population for both extremes and against intermediates), and (again contrary to theoretical expectation), showed such selection could be extremely effective, increasing variance, establishing and maintaining polymorphisms
Polymorphism (biology)
Polymorphism in biology occurs when two or more clearly different phenotypes exist in the same population of a species — in other words, the occurrence of more than one form or morph...
, and, if the selected individuals were allowed to choose their mates, dividing the population into two partially isolated parts, something which is a step towards speciation
Speciation
Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages...
.
External links
- Obituary in The Telegraph
- Obituary in The Times
- http://www.emma.cam.ac.uk/teaching/fellows/display/index.cfm?fellow=67
- http://jmthodaygeneticist.com/ Professor Thoday's personal website, which includes full publications listing.