|Fields||Energetics and Obesity|
|Institutions||University of Aberdeen|
|Notable awards||FRSE (2004)
FMed Sci (2008)
Professor John Speakman FRSE FRSB FMedSci is a British biologist working at the University of Aberdeen, Institute of Biological and Environmental Sciences, for which he was Director from 2007 to 2011. He leads 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. He was awarded Doctor of Science (DSc) degrees by both the University of Aberdeen (1996) and University of Stirling (2009). In 2011 Speakman took up a joint position at the Chinese Academy of Sciences, Institute of Genetics and Developmental Biology, in Beijing, as a 1000 talents Professor, where he heads the molecular energetics group which is part of the State key laboratory of molecular developmental biology. In 2016 he received a Royal Society Wolfson Research Merit Award from the Royal Society of London.
Speakman is well known for his work on 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 phenotypes 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. 
With Aberdeen colleague Ela Krol, among others, he has published a series of over 20 papers in the Journal of Experimental Biology, known as the ‘limits’ series, which culminated in a novel hypothesis that animal energy expenditure is limited by the capacity to dissipate body heat. This idea – the “heat dissipation limit hypothesis” (HDL) was published by Speakman and Krol in the Journal of Animal Ecology in 2010. The idea is claimed to have wide implications for our understanding of many aspects of ecophysiology and ecology – such as limits on range distributions, maximum possible sizes of endothermic animals e.g. dinosaurs, Bergmann’s rule, effects of climate change etc. The idea is revolutionary because it shifts the fundamental locus of control over energy expenditure from extrinsic factors outside the animal (e.g. food supply, fractal supply system, uptake capacity), to intrinsic factors inside an animal (heat dissipation capacity). An independent review of studies of energy expenditure concluded that the HDL hypothesis provided a better explanation of the patterns of energy expenditure in endotherms than does the metabolic theory of ecology.
In 2005 he gave the Royal Dick Vet memorial lecture during the Edinburgh Science festival, in 2011 the Clive McCay endowment lecture at Cornell University and in 2014 the Irving-Scholander Prize lecture at the University of Fairbanks, Alaska.
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 1991 he was elected fellow of the UK Institute of Biology, later renamed the Society of Biology and latterly the Royal Society of Biology. 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 in 2011 to the Academy of Europe (Academia Europaea), and in 2014 The Obesity Society of the USA. He was made a Bing Zhi forum Professor of the Chinese Academy of Sciences Institute of Zoology in Beijing (2010) and holds honorary Professorial positions at the University of Wenzhou (Zhejiang) (2014) and the University of Dali (Yunnan) (2014). He was the first non-Chinese recipient of a ‘Great wall’ professorship from the CAS-Novonordisk Foundation (2011) and in 2015 was the first Briton ever to be awarded the Chinese Academy of Sciences medal for International cooperation.
He is on the board of reviewing editors at the journal Science (2011-date) and is Deputy Editor in Chief of Biology Open (2010-date).
Speakman writes a monthly popular science column for the magazine ‘Newton’ (translated into Chinese by an ex-student Lina Zhang) and has also published two popular science books consisting of the compiled English versions of these articles.
- Speakman, John. "Awards & Prizes". University of Aberdeen, UK. Retrieved March 13, 2011.
- "John Speakman". University of Aberdeen, UK. Retrieved March 13, 2011.
- "Energetics Research Group". University of Aberdeen, UK. Retrieved March 13, 2011.
- Speakman, J.R. (1997). Doubly labelled water: theory and practice. London: Chapman & Hall. ISBN 0-412-63780-4.
- J. R. Speakman. (2008). Thrifty genes for obesity, an attractive but flawed idea, and an alternative perspective: the 'drifty gene' hypothesis. International Journal of Obesity, 32, 1611-7. doi
- Speakman, J.R. (2006). The genetics of obesity: five fundamental problems with the famine hypothesis. In G. Fantuzzi, and T. Mazzone, (Eds) Adipose tissue and adipokines in health and disease. Humana Press, New York.
- J. R. Speakman. (2007). A nonadaptive scenario explaining the genetic predisposition to obesity: the "predation release" hypothesis. Cell metabolism, 6, 5-12. doi
- A. M. Prentice, B. J. Hennig and A. J. Fulford. (2008). Evolutionary origins of the obesity epidemic: natural selection of thrifty genes or genetic drift following predation release? International Journal of Obesity, 32, 1607-10, doi
- J. R. Speakman, K. A. Rance and A. M. Johnstone. (2008). Polymorphisms of the FTO gene are associated with variation in energy intake, but not energy expenditure. Obesity, 16, 1961-5. doi
- Speakman, J.R. and Krol, E (2010) Maximal heat dissipation capacity and hyperthermia risk: neglected key factors in the ecology of endotherms Journal of Animal Ecology 79: 726-746 doi
- Gremillet et a. (2012) Heat dissipation limit theory and the evolution of avian functional traits in a warming world. Functional eology 26: 1001-1006 doi
- Hudson, L.N. et al (2013) The relationship between body mass and field metabolic rate among individual birds and mammals. Journal of Animal Ecology 82: 1009-2020 doi
- Speakman, J.R. (2014) Pandas – dead end or dead wrong? and eleven other short stories from the frontiers of bioscience, 2014. Create space publishing ISBN 978-1505548877
- Speakman, J.R. (2015) How dogs make us fall in love with them and eleven other short stories from the frontiers of bioscience 2015. Createspace publishing ISBN 978-1519681867