![Professor John Speakman Professor John Speakman](/img/200x200/staffpages/uploads/nhi158/johnbird.jpg)
FRS FMedSci FRSE FRSB FRSA FLS FRSS
Chair in Zoology
- About
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- Email Address
- j.speakman@abdn.ac.uk
- Telephone Number
- +44 (0)1224 272879
- Office Address
- School/Department
- School of Biological Sciences
Biography
For Speakman's biography see the Wikipedia page entry.
External Memberships
Committees
I serve on the following external committees:
Royal Society
- Section 10 medical sciences election committee
- Newton Fund International Fellowships Chairman
- University Research Fellowships (Panel B)
Royal Society of Edinburgh
- Section A3 election committee
Journals
In the last decade I have also served on the editorial boards of the following journals:
- Mammal review 2002 - date
- Aging Cell (section editor) 2004 - 2007
- Journal of Comparative Physiology 2004 - date
- Functional Ecology 2004 - 2009
- Biology letters 2008 - 2013
- Biology Open (deputy editor in chief) 2011 - 2018
- Molecular metabolism (founding board member) 2011 - date
- Science 2011 - date
- IUBMB Life 2012 - date
- Clinical Endocrinology Physiology and Pharmacology 2013 - 2015
- Journal of Genetics and Genomics 2013 - date
- Physiological and Biochemical zoology 2015 - date
- Annals of Human Genetics 2016 - 2019
- International Journal of Obesity 2017 - date
- China Science Life Science 2018 - date
- Philosophical transactions of the Royal Society 2018 - date
- Research
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Research Overview
Over my career so far I have worked on a wide range of topics. Binding them all together is a singular focus on understanding the factors that influence and limit energy expenditure. Since energy is central to all biological processes it provides a common currency for gaining deeper knowledge of the evolutionary forces that have molded animal (including human) adaptations. Early in my career, in the late 1980s and early 1990s, I was instrumental in developing the theoretical and practical basis of an isotope-based methodology for the study of energy demands in free-living animals: called the doubly-labelled water (DLW) technique. In 1997 I published a 400 page book (Doubly-labelled water: theory and practice. Springer New York) which has become the standard reference for the method. This expertise has led my group to become the partner of choice for scientists around the world wishing to apply these techniques in their own studies.
I have used these techniques and the energy balance approach to provide paradigm shifting insights into our understanding of the limits on animal energy expenditure (notably the heat dissipation limits theory), the biology of ageing, and the evolutionary context of the human obesity epidemic (particularly the ‘drifty gene’ hypothesis). These studies have broad implications across many areas of enquiry. A common theme of my work has been to challenge and overturn prevailing ideas with new knowledge gathered from the study of energetics.
Limits to Sustained energy expenditure and intake: I have a long interest in the factors that limit animal expenditure over periods of days and weeks: called sustained energy expenditure (or sustained energy intake – since over such long periods the two must balance). This approach has been used to provide valuable insights in several different areas. In 1998 using the DLW method we showed that African wild dogs have extremely high levels of free-living energy expenditure due mostly to the high costs of hunting (Gorman et al 1998 Nature391: 479-481: front cover). This creates a problem for wild dogs because if their prey is stolen (e.g. by lions or hyenas) the cost of replacing the food becomes extremely expensive. A mathematical model showed that only a slight shift in the level of kleptoparasitism would push the dogs over an energetic precipice to physiologically unsustainable levels of expenditure. This explained why wild dogs are driven to extinction in reserves where large lion and hyena populations are fostered for tourism. It has been widely assumed that this problem would also pertain to cheetah that are similarly kleptoparasitised, and also presumed to have high hunting costs, but work in collaboration with ex-student Michael Scantlebury has suggested otherwise (Scantlebury et al 2014 Science). This is primarily because while cheetah hunts are costly per unit time, they are very short in duration. Hence cheetah have flexibility to sustain much greater levels of kleptoparasitism than wild dogs. At the other end of the metabolic spectrum it has been widely speculated that to survive on their bamboo diet Giant Pandas must have low metabolic rates. We have shown that Panda metabolic rates are among the lowest ever measured in the Eutheria, and can be traced to a panda unique single nucleotide polymorphism in the dual oxidase 2 (DUOX2) gene, which causes a premature stop codon and truncated protein. DUOX2 is critical for thyroid hormone synthesis (Nie et al 2015 Science 349: 171-4).
For most animals breeding is the most energetically expensive period in their lives. They consequently time such effort to match maximal food availability. In some situations this timing may go awry as was observed in populations of blue tits nesting in different habitats in Corsica. Quantification of energy demands using DLW of synchronised and non-synchronised individuals (Thomas et al 2001 Science 291: 2598-2600) showed that desynchronised individuals must work close to their physiological capacity, significantly increasing their mortality rate. This finding has major implications because often the timing of breeding is hard wired into circannual daylight cycles. If the timing of the pulse of maximal food availability changes – for example, due to global climate change, populations may mis-time their breeding events with catastrophic consequences. Elevated ambient temperatures may also have more direct effects on energy expenditure, and this is likely to be particularly important in hibernating animals. Using a mathematical model of hibernal energy balance my group was able to show how climate change will impact the biogeography of bats in North America (Humphries et al 2002 Nature 418: 313-316).
To study this phenomenon of limits in more detail we group have used lactating mice as a model system. Starting in 1996 (Speakman and McQueenie 1996 Physiol. Zool. 69: 746-769) this has led to a series of more than 30 papers mostly in the Journal of Experimental Biology. This work was expanded into a more comprehensive theory concerning the more general limits on animal metabolic rates (the heat dissipation limit theory). The fundamental feature of this revolutionary idea is that endothermic animals are not normally constrained by extrinsic energy supply, but rather are limited by their ability to dissipate body heat, combined with the risk of hyperthermia. This theory was summarised in a landmark paper in 2010 (Speakman and Krol 2010 J. Anim. Ecol. 79: 726-746).
Limits on heat dissipation may have important ramifications as our climate changes. This is because the risk of heatwaves is anticipated to rise in the future. In collaboration with Dr Zhi-Jun Zhao at the university of Wenzhou in China, we have shown in mice and desert hamsters that such changes may have devastating effects paticularly during lactation when there seems to be a critical window of vulnerability to high temperatures (Zhao et al 2020: PNAS).
Energetics and the biology of ageing and life histories. One of the important areas where the heat dissipation limit theory has significant implications is the study of ageing and life histories. In fact ageing, life histories and energetics have a long history of association via the ‘rate of living theory’ which was the first comprehensive theory of ageing, proposed early during the last century. This theory was based on the empirical observation that species with lower rates of metabolism live longer, and found a potential mechanism in the observations that free-radicals are an inevitable by product of oxidative metabolism. The rate of living and free-radical theory of ageing was the dominant theory of ageing until the late 1990s, and the suggested role of free-radicals and oxidative stress as mediators of life history trade-offs has been dominant since that time. My work, (along with many other researchers), has been instrumental in overturning both these ideas. By measuring the energy metabolism of individual mice he showed that it was actually mice with the higher rates of metabolism that lived longest (Speakman et al 2004 Aging cell3: 87-95). I also showed that the links between low metabolism and lifespan are statistical artefacts of not adequately accounting for co-variation due to body size and phylogeny (Speakman, 2005 J. Expt. Biol. 208: 1717-1730.
Energetics and obesity: I have made two distinct contributions to this field. The first is to revolutionise our perceptions of the evolutionary underpinning of the epidemic. Until the mid-2000’s the only evolutionary model for the development of obesity was the ‘thrifty’ gene hypothesis, proposed by Neel in 1962. This suggested that we become obese because in our ancient past deposition of fat provided a safeguard against periods of famine. However, in modern society the system promoting fat storage during periods of plenty results in deposition of excessive amounts of fat in preparation for a famine that never comes: and the result is an obesity epidemic. I have highlighted the many flaws in this superficially attractive idea, and suggested the alternative hypothesis that in our ancient past we were probably very good at regulating our body weight because of the twin threats of starvation and predation. However, 2 million years ago with the invention of fire, weapons and social behaviour we effectively removed the threat of predation: allowing the genes that define our upper body weight control point to drift in time. Because these genes are drifting, rather than being under selection, this explains why everyone does not get fat in modern society. This new idea was elaborated in a breakthrough paper in 2007 (Speakman, 2007 Cell metabolism 6: 5-11) and was subsequently coined the 'drifty' gene hypothesis (Speakman 2008 Int. J. Obesity 32: 1611-1617). This novel approach completely reconceptualises the reasons underpinning the obesity epidemic, and is gathering increasing support from, for example, the GWAS studies of obesity.
My second main contribution to the obesity field is to enter the debate concerning the roles of physical activity and energy expenditure as factors driving the epidemic. In other words, do we eat too much or expend too little (or both). In the 1970 and 1980s it was widely thought that the problem was over-eating, but a highly influential paper by Prentice and Jebb in 1991 suggested the problem was really increasing levels of sedentary behaviour. By the early 2000’s, when I entered this field, it was almost universally believed that reductions in energy expenditure were the main issue. My group published the first data showing that the newly discovered FTO gene (the first GWAS gene linked to obesity) has its effects via modulation of energy intake rather than energy expenditure (Speakman et al 2008 Obesity 16: 1961-1965). This seminal contribution to our understanding of the biological effects of FTO has become the 22nd most cited paper from over 7000 papers published in Obesity over the past 15 years. In collaboration with Klaas Westerterp, we have surveyed data on energy demands dating back to the 1980s. This work showed two things: first that energy expenditure has not declined over this period, and second that the energy demands of humans actually fit very closely to the expected levels of expenditure based on studies of wild animals (Westerterp and Speakman 2008. Int. J. Obesity 32: 1256-1263). This work was an integral part of a turning tide, and now, the idea that the problem with the obesity epidemic is elevated food intake, rather than reduced expenditure, is main stream again.
Current Research
The work of my group currently addresses several key issues with respect to energy balance
1) the role and mechanism by which restriction of calorie intake leads to improved health and lifespan.
This work has been mainly performed in mice and utilised a method of exposing aniamls to graded levels of restriction to elucidate the patterns of change as restriction becomes more intense. Full details of this work can be found on the open science framework pages https://osf.io/9yath. In 2020 I published a revolutionary new idea about why CR has the effects it does - called the 'clean cupboards' hypothesis published in the Naional Science Review
2) The impact of macronutrients on wieght regulation.
There is a long standing debate about the roles played by different macronutrients in weight regulation. We have been working in this field mostly by exposing mice to different macronutrient diets and monitoring their responses in terms of food intake and body weight. A major paper on this work was published in Cell metabolism in 2018. (Hu et al 2018: Cell metabolism).
3) Measuring energy demands of free-living animals and humans using the doubly-labelled water method
4) Exploring the links between fast food consumption and obesity
5) The IAEA doubly-labelled water human database
https://doubly-labelled-water-database.iaea.org/home
- Publications
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Page 5 of 7 Results 401 to 500 of 679
Polymorphisms of the FTO gene are associated with variation in energy intake, but not energy expenditure
Obesity, vol. 16, no. 8, pp. 1961-1965Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/oby.2008.318
Stable carbon isotopes in exhaled breath as tracers for dietary information in birds and mammals
Journal of Experimental Biology, vol. 211, no. 14, pp. 2233-2238Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1242/jeb.018523
Divergent physical activity and novel alternative responses to high fat feeding in polygenic fat and lean mice
Behavior Genetics, vol. 38, no. 3, pp. 292-300Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1007/s10519-008-9199-y
Effects of structural and functional habitat gaps on breeding woodland birds: working harder for less
Landscape Ecology, vol. 23, no. 5, pp. 615-626Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1007/s10980-008-9225-8
Estimating field metabolic rates of pinnipeds: doubly labelled water gets the seal of approval
Functional Ecology, vol. 22, no. 2, pp. 245-254Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1365-2435.2007.01368.x
Snake Pipefish Entelurus aequoreus are poor food for seabirds
Ibis, vol. 150, no. 2, pp. 413-415Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1474-919X.2007.00780.x
Evidence for lifespan extension and delayed age-related biomarkers in insulin receptor substrate 1 null mice
The FASEB Journal, vol. 22, no. 3, pp. 807-818Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1096/fj.07-9261com
Intra-specific variation in resting metabolic rate in MF1 mice is not associated with membrane lipid desaturation in the liver
Mechanisms of Ageing and Development, vol. 129, no. 3, pp. 129-137Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.mad.2007.11.001
Protein synthesis and antioxidant capacity in aging mice: Effects of long-term voluntary exercise
Physiological and Biochemical Zoology, vol. 81, no. 2, pp. 148-157Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1086/525289
Lifelong α-tocopherol supplementation increases the median life span of C57BL/6 mice in the cold but has only minor effects on oxidative damage
Rejuvenation Research, vol. 11, no. 1, pp. 83-96Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1089/rej.2007.0586
Evolutionary biology: A first for bats
Contributions to Journals: Short Survey- [ONLINE] DOI: https://doi.org/10.1038/451774a
- [ONLINE] View publication in Scopus
Feeding behaviour in galanin knockout mice supports a role of galanin in fat intake and preference
Journal of Neuroendocrinology, vol. 20, no. 2, pp. 199-206Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1365-2826.2007.01638.x
The physiological costs of reproduction in small mammals
Philosophical Transactions of the Royal Society of London. Series B: Biological sciences, vol. 363, no. 1490, pp. 375-398Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1098/rstb.2007.2145
Bat breath reveals metabolic substrate use in free-ranging vampires
Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology, vol. 178, no. 1, pp. 9-16Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1007/s00360-007-0194-z
Chronic central administration of apelin-13 over 10 days increases food intake, body weight, locomotor activity and body temperature in C57BL/6 mice
Journal of Neuroendocrinology, vol. 20, no. 1, pp. 79-84Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1365-2826.2007.01617.x
Hunger Does Not Diminish Over Time in Mice Under Protracted Caloric Restriction
Rejuvenation Research, vol. 10, no. 4, pp. 533-542Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1089/rej.2007.0555
Calorie-restricted mice that gorge show less ability to compensate for reduced energy intake
Physiology and Behavior, vol. 92, no. 5, pp. 985-992Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physbeh.2007.07.005
Gene environment interactions and the origin of the modern obesity epidemic: A novel "nonadaptive drift" scenario
Appetite and Body Weight: Integrative Systems and the Development of Anti-Obesity Drugs. Kirkham, T. C., Cooper, S. J. (eds.). Elsevier Inc., pp. 301-322, 22 pagesChapters in Books, Reports and Conference Proceedings: Chapters- [ONLINE] DOI: https://doi.org/10.1016/B978-012370633-1/50012-8
- [ONLINE] View publication in Scopus
Limits to sustained energy intake. X.: Effects of fur removal on reproductive performance in laboratory mice
Journal of Experimental Biology, vol. 210, pp. 4233-4243Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1242/jeb.009779
Quantitative trait Loci for regional adiposity in mouse lines divergently selected for food intake
Obesity, vol. 15, no. 12, pp. 2994-3004Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/oby.2007.357
Sex- and concentration-dependent effects of predator feces on seasonal regulation of body mass in the bank vole Clethrionomys glareolus
Hormones and Behavior, vol. 52, no. 4, pp. 436-444Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1016/j.yhbeh.2007.06.009
Water requirements as a bottleneck in the reintroduction of European roe deer to the southern edge of its range
Canadian Journal Of Zoology/Revue Canadien De Zoologie, vol. 85, no. 11, pp. 1182-1192Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1139/Z07-098
Nectar-feeding bats fuel their high metabolism directly with exogenous carbohydrates
Functional Ecology, vol. 21, no. 5, pp. 913-921Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1365-2435.2007.01321.x
Energetic costs of parasitism in the Cape ground squirrel Xerus inauris
Proceedings of the Royal Society of London. B, Biological Sciences, vol. 274, no. 1622, pp. 2169-2177Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1098/rspb.2007.0690
Effects of mass and body composition on fasting fuel utilisation in grey seal pups (Halichoerus grypus Fabricius): an experimental study using supplementary feeding
Journal of Experimental Biology, vol. 210, no. 17, pp. 3043-3053Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1242/jeb.009381
Expression of neuromedin B in adipose tissue and its regulation by changes in energy balance
Journal of Molecular Endocrinology, vol. 39, no. 3, pp. 199-210Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1677/JME-07-0071
AMPK is essential for energy homeostasis regulation and glucose sensing by POMC and AgRP neurons
The Journal of Clinical Investigation, vol. 117, no. 8, pp. 2325-2336Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1172/JCI31516
Assortative mating for obesity
The American Journal of Clinical Nutrition, vol. 86, no. 2, pp. 316-323Contributions to Journals: ArticlesPlasma leptin levels are related to body composition, sex, insulin levels and the A55V polymorphism of the UCP2 gene
International Journal of Obesity, vol. 31, no. 8, pp. 1311-1318Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/sj.ijo.0803535
The measurement of resting metabolic rate in preschool children
Obesity, vol. 15, no. 8, pp. 1930-1932Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/oby.2007.230
A nonadaptive scenario explaining the genetic predisposition to obesity: the "Predation release" hypothesis
Cell Metabolism, vol. 6, no. 1, pp. 5-12Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.cmet.2007.06.004
Predicting the effects of body fatness on food intake and performance of sheep
British Journal of Nutrition, vol. 97, no. 6, pp. 1206-1215Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1017/S0007114507691922
Prevention of diet-induced obesity and impaired glucose tolerance in rats following administration of leptin to their mothers
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, vol. 292, no. 5, pp. R1810-R1818Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1152/ajpregu.00676.2006
The Lou/C rat is proportionally smaller than the Wistar and not anorexic or hyperactive as previously reported
International Journal of Obesity, vol. 31, no. S1, pp. S84-S84Contributions to Journals: Abstracts- [ONLINE] DOI: https://doi.org/10.1038/sj.ijo.0803597
Starving for life: what animal studies can and cannot tell us about the use of caloric restriction to prolong human lifespan
The Journal of Nutrition, vol. 137, no. 4, pp. 1078-1086Contributions to Journals: ArticlesAnimal models of obesity
Obesity Reviews, vol. 8, no. Suppl 1, pp. 55-61Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1467-789X.2007.00319.x
Intake compensates for resting metabolic rate variation in female C57BL/6J mice fed high-fat diets
Obesity, vol. 15, no. 3, pp. 600-606Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/oby.2007.550
Regulation of body mass and adiposity in the field vole, Microtus agrestis: a model of leptin resistance
Journal of Endocrinology, vol. 192, no. 2, pp. 271-278Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1677/JOE-06-0074
The energy cost of reproduction in small rodents
Acta Theriologica Sinica, vol. 27, no. 1, pp. 1-13Contributions to Journals: Review articles- [ONLINE] View publication in Scopus
Associations between basal metabolic rate and reproductive performance in C57BL/6J mice
Journal of Experimental Biology, vol. 210, no. 1, pp. 65-74Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1242/jeb.02625
Seasonal variation in resting metabolic rates (RMR) and daily energy expenditures (DEE)
Integrative and Comparative Biology, vol. 46Contributions to Journals: ArticlesIndividually variable energy management strategies in relation to energetic costs of egg production
Ecology, vol. 87, no. 10, pp. 2447-2458Contributions to Journals: ArticlesHaving it all: historical energy intakes do not generate the anticipated trade-offs in fecundity
Proceedings of the Royal Society of London. B, Biological Sciences, vol. 273, no. 1592 , pp. 1369-1374Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1098/rspb.2005.3456
A theory of associating food types with their postingestive consequences
The American Naturalist, vol. 167, no. 5, pp. 705-716Contributions to Journals: ArticlesThrifty genes for obesity and the metabolic syndrome - Time to call off the search?
Diabetes and Vascular Disease Research, vol. 3, no. 1, pp. 7-11Contributions to Journals: Review articles- [ONLINE] DOI: https://doi.org/10.3132/dvdr.2006.010
- [ONLINE] View publication in Scopus
Energetics reveals physiologically distinct castes in a eusocial mammal
Nature, vol. 440, pp. 795-797Contributions to Journals: Letters- [ONLINE] DOI: https://doi.org/10.1038/nature04578
Effects of climate on oxygen consumption and energy intake of chromosomally divergent populations of the House Mouse (Mus musculus domesticus) from the island of Madeira (North Atlantic, Portugal)
Functional Ecology, vol. 20, no. 2, pp. 330-339Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1365-2435.2006.01091.x
Additional anthropometric measures may improve the predictability of basal metabolic rate in adult subjects
European Journal of Clinical Nutrition, vol. 60, no. 12, pp. 1437-1444Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/sj.ejcn.1602477
Age related variation in the energy costs of torpor in Daubenton's bat: effects on fat accumulation prior to hibernation
Acta Chiropterologica, vol. 8, no. 2, pp. 509-521Contributions to Journals: ArticlesHuddling in groups leads to daily energy savings in free-living African Four-Striped Grass Mice, Rhabdomys pumilio
Functional Ecology, vol. 20, pp. 166-173Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1365-2435.2006.01074.x
Seasonal metabolism of juvenile green turtles (Chelonia mydas) at Heron Island, Australia
Canadian Journal Of Zoology/Revue Canadien De Zoologie, vol. 84, pp. 125-135Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1139/Z05-185
Seasonal variation in the metabolic rate and body composition of female grey seals: fat conservation prior to high-cost reproduction in a capital breeder?
Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology, vol. 176, no. 6, pp. 505-512Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1007/s00360-006-0072-0
Some mathematical and technical issues in the measurement and interpretation of open-circuit indirect calorimetry in small animals
International Journal of Obesity, vol. 30, pp. 1322-1331Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1038/sj.ijo.0803280
The energy costs of sexual dimorphism in mole-rats are morphological not behavioural
Proceedings of the Royal Society of London. B, Biological Sciences, vol. 273, pp. 57-63Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1098/rspb.2005.3280
The ice diet
New Scientist, vol. 188, no. 2530, pp. 65Contributions to Journals: LettersA positive association between resting and field metabolic rates in weasels
Integrative and Comparative Biology, vol. 45, no. 6, pp. 1080Contributions to Journals: ArticlesFactors influencing variation in basal metabolic rate include fat-free mass, fat mass, age, and circulating thyroxine but not sex, circulating leptin, or triiodothyronine
The American Journal of Clinical Nutrition, vol. 82, no. 5, pp. 941-948Contributions to Journals: ArticlesA life history model of somatic damage associated with resource acquisition: damage protection or prevention?
Journal of Theoretical Biology, vol. 235, no. 3, pp. 305-317Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.jtbi.2005.01.009
A paternally imprinted QTL for mature body mass on mouse Chromosome 8
Mammalian Genome, vol. 16, no. 8, pp. 567-577Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1007/s00335-005-0012-4
The role of insulin receptor substrate 2 in hypothalamic and β cell function
Journal of Clinical Investigation, vol. 115, no. 4, pp. 940-950Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1172/JCI24445
- [ONLINE] View publication in Scopus
Associations between BMI, social strata and the estimated energy content of foods
International Journal of Obesity, vol. 29, pp. 1281-1288Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/sj.ijo.0803018
Body size, energy metabolism and lifespan
Journal of Experimental Biology, vol. 208, pp. 1717-1730Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1242/jeb.01556
Comparison of different approaches for the calculation of energy expenditure using doubly labeled water in a small mammal
Physiological and Biochemical Zoology, vol. 78, pp. 650-667Contributions to Journals: ArticlesContribution of different mechanisms to compensation for energy restriction in the mouse
Obesity Research, vol. 13, no. 9, pp. 1548-1557Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/oby.2005.190
Correlations between physiology and lifespan - two widely ignored problems with comparative studies
Aging Cell, vol. 4, pp. 167-175Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1111/j.1474-9726.2005.00162.x
Effect of mild restriction of food intake on the speed of racing Greyhounds
American Journal of Veterinary Research, vol. 66, pp. 1065-1070Contributions to Journals: ArticlesEnergetics of cooperative breeding in meerkats Suricata Suricatta
International Congress Series, vol. 1275, pp. 367-374Contributions to Journals: ArticlesExercise by lifelong voluntary wheel running reduces subsarcolemmal and interfibrillar mitochondrial hydrogen peroxide production in the heart
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, vol. 289Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1152/ajpregu.00396.2005
Expenditure freeze: the metabolic response of small mammals to cold environments
Ecology Letters, vol. 8, pp. 1326-1333Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1111/j.1461-0248.2005.00839.x
Impact of ectoparasitic blowfly larvae (Protocalliphora spp.) on the behavior and energetics of nestling Blue Tits
Journal of Field Ornithology, vol. 76, no. 4, pp. 402-410Contributions to Journals: ArticlesLimits to sustained energy intake IX: a review of hypotheses
Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology, vol. 175, pp. 375-394Contributions to Journals: Literature Reviews- [ONLINE] DOI: https://doi.org/10.1007/s00360-005-0013-3
Low energy values of fish as a probable cause of a major seabird breeding failure in the North Sea
Marine Ecology Progress Series, vol. 294, pp. 18Contributions to Journals: ArticlesMice with low metabolic rates are not susceptible to weight gain when fed a high-fat diet
Obesity Research, vol. 13, no. 3, pp. 556-566Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1038/oby.2005.59
PIXImus DXA with different software needs individual calibration to accurately predict fat mass
Obesity Research, vol. 13, pp. 1558-1565Contributions to Journals: ArticlesSeasonal energetics of the Hottentot golden mole at 1500m altitude
Experimental Physiology, vol. 84, pp. 739-745Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physbeh.2005.02.022
The role of insulin receptor substrate 2 in hypothalamic and beta cell function
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Comparison of the cost of short flights in a nectarivorous and a non-nectarivorous bird
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The energetic cost of variations in wing span and wing asymmetry in the zebra finch Taeniopygia guttata
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The energy cost of loaded flight is substantially lower than expected due to alterations in flight kinematics
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AMP-activated protein kinase is up-regulated in the brown adipose tissue of mice with high resting metabolic rate
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Individual variations in resting metabolic rate in C57BL/6J mice do not predispose to weight or fat gain over 6 months on diets of varying fat content
International Journal of Obesity, vol. 28Contributions to Journals: ArticlesMechanisms of compensation for energy restriction in the mouse
International Journal of Obesity, vol. 28Contributions to Journals: ArticlesBirds sacrifice oxidative protection for reproduction
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Differential energy costs of winter acclimatized common spiny mice Acomys cahirinus from two adjacent habitats
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Long-term cold acclimation leads to high Q(10) effects on oxygen consumption of loggerhead sea turtles caretta caretta
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Functional Ecology, vol. 18, pp. 168-183Contributions to Journals: Literature ReviewsMetabolic power of European starlings Sturnus vulgaris during flight in a wind tunnel, estimated from heat transfer modelling, doubly labelled water and mask respirometry
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Obesity: The integrated roles of environment and genetics
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Peripherally administered [Nle(4),D-Phe(7)]-alpha-melanocyte stimulating hormone increases resting metabolic rate, while peripheral agouti-related protein has no effect, in wild type C57BL/6 and ob/ob mice
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Photoperiodic effects on body mass, energy balance and hypothalamic gene expression in the bank vole
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Reproductive energetics of captive and free-ranging Egyptian fruit bats (Rousettus aegyptiacus)
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Energy Metabolism and Lifespan Determination. Mattson, M. P. (ed.). Elsevier Science, pp. 35-68, 34 pagesChapters in Books, Reports and Conference Proceedings: Chapters- [ONLINE] DOI: https://doi.org/10.1016/S1566-3124(03)14003-5
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Resting and daily energy expenditures of free-living field voles are positively correlated but reflect extrinsic rather than intrinsic effects
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The energy cost of song in the canary, Serinus canaria
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Limits to sustained energy intake VI. Energetics of lactation in laboratory mice at thermoneutrality
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Obesity: Part three - Failed solutions and new ideas
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Obesity: Part two - The biology of body weight regulation
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