John Speakman
Encyclopedia
Professor John Speakman is a British biologist
working at the University of Aberdeen
, Institute of Biological and Environmental Sciences. He directs the University's Energetics Research Group, which is one of the world's leading groups using doubly labeled water (DLW) to investigate energy expenditure and balance
in animals. During the mid 1980s and early 1990s, Speakman made many contributions to the development of the DLW method, culminating in the book "Doubly labelled water: theory and practice",
published in 1997 that remains the standard reference work for applications of this methodology in humans and other animals.
Speakman is also well known for his work in obesity
, in particular for criticising a long-established theory for obesity known as the thrifty gene hypothesis
. His alternative hypothesis proposes that the modern distribution of obese phenotype
s arose via the release from predation
and random genetic drift: the 'drifty gene hypothesis
'.
This idea is controversial and has been criticised by others that support the original thrifty gene hypothesis.
Speakman's group was the first to link genetic variation
to differences in food consumption in humans by examining polymorphic
variation in the Fat mass and obesity associated (FTO) gene
.
Speakman was awarded the Zoological Society of London
scientific medal in 1995, and the Royal Society of Edinburgh
Saltire Society
Scottish Science medal in 2003. In 2004, he was elected to the fellowship of the Royal Society of Edinburgh
, in 2008 to the UK Academy of Medical Sciences
, and in 2009 to the Royal Society of Arts
in London
.
Biologist
A biologist is a scientist devoted to and producing results in biology through the study of life. Typically biologists study organisms and their relationship to their environment. Biologists involved in basic research attempt to discover underlying mechanisms that govern how organisms work...
working at the University of Aberdeen
University of Aberdeen
The University of Aberdeen, an ancient university founded in 1495, in Aberdeen, Scotland, is a British university. It is the third oldest university in Scotland, and the fifth oldest in the United Kingdom and wider English-speaking world...
, Institute of Biological and Environmental Sciences. He directs the University's Energetics Research Group, which is one of the world's leading groups using doubly labeled water (DLW) to investigate energy expenditure and balance
Energy balance (biology)
In biology, energy balance is the biological homeostasis of energy in living systems. It is measured with the following equation: Energy intake = internal heat produced + external work + storage. It is also an aspect of bioenergetics, concerning energy flow through living systems.It generally uses...
in animals. During the mid 1980s and early 1990s, Speakman made many contributions to the development of the DLW method, culminating in the book "Doubly labelled water: theory and practice",
published in 1997 that remains the standard reference work for applications of this methodology in humans and other animals.
Speakman is also well known for his work in obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...
, in particular for criticising a long-established theory for obesity known as the thrifty gene hypothesis
Thrifty gene hypothesis
The thrifty gene hypothesis was proposed by geneticist James V. Neel in 1962 to resolve a fundamental problem. Diabetes is clearly a very harmful medical condition. Yet it is quite common, and it was already evident to Neel that it likely had a strong genetic basis...
. His alternative hypothesis proposes that the modern distribution of obese phenotype
Phenotype
A phenotype is an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, behavior, and products of behavior...
s arose via the release from predation
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
and random genetic drift: the 'drifty gene hypothesis
Drifty gene hypothesis
The “”Drifty gene hypothesis”” was proposed by the British biologist John Speakman as an alternative to the thrifty gene hypothesis originally proposed by James V Neel in 1962...
'.
This idea is controversial and has been criticised by others that support the original thrifty gene hypothesis.
Speakman's group was the first to link 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...
to differences in food consumption in humans by examining polymorphic
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...
variation in the Fat mass and obesity associated (FTO) gene
FTO gene
Fat mass and obesity-associated protein also known as alpha-ketoglutarate-dependent dioxygenase FTO is an enzyme that in humans is encoded by the FTO gene located on chromosome 16...
.
Speakman was awarded the Zoological Society of London
Zoological Society of London
The Zoological Society of London is a charity devoted to the worldwide conservation of animals and their habitats...
scientific medal in 1995, and the Royal Society of Edinburgh
Royal Society of Edinburgh
The Royal Society of Edinburgh is Scotland's national academy of science and letters. It is a registered charity, operating on a wholly independent and non-party-political basis and providing public benefit throughout Scotland...
Saltire Society
Saltire Society
The Saltire Society was established in 1936 to encourage everything that might improve the quality of life in Scotland and restore the country to its proper place as a creative force in European civilisation....
Scottish Science medal in 2003. In 2004, he was elected to the fellowship of the Royal Society of Edinburgh
Royal Society of Edinburgh
The Royal Society of Edinburgh is Scotland's national academy of science and letters. It is a registered charity, operating on a wholly independent and non-party-political basis and providing public benefit throughout Scotland...
, in 2008 to the UK Academy of Medical Sciences
Academy of Medical Sciences
The Academy of Medical Sciences is the United Kingdom's national academy of medical sciences. It was established in 1998 on the recommendation of a group that was chaired by Michael Atiyah. Its president is John Irving Bell....
, and in 2009 to the Royal Society of Arts
Royal Society of Arts
The Royal Society for the encouragement of Arts, Manufacturers and Commerce is a British multi-disciplinary institution, based in London. The name Royal Society of Arts is frequently used for brevity...
in London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
.