Measures of physiological stress: a transparent or opaque window into the status, management and conservation of species?

We discuss the methodological issues associated with measuring stress hormones in wild animals. We discuss five questions that we think should be considered about the use of stress hormone measurements in conservation physiology. We present a meta-analysis showing that human activities consistently increase stress hormone levels across vertebrates.

[1]  Martin Wikelski,et al.  Conservation physiology. , 2020, Trends in ecology & evolution.

[2]  D. Costantini,et al.  Biomarkers of oxidative status: missing tools in conservation physiology , 2014, Conservation physiology.

[3]  Pat Monaghan,et al.  Stress exposure in early post-natal life reduces telomere length: an experimental demonstration in a long-lived seabird , 2014, Proceedings of the Royal Society B: Biological Sciences.

[4]  Simon Verhulst,et al.  Measuring telomere length and telomere dynamics in evolutionary biology and ecology , 2014, Methods in Ecology and Evolution.

[5]  C. L. Madliger,et al.  The Need for a Predictive, Context‐Dependent Approach to the Application of Stress Hormones in Conservation , 2014, Conservation biology : the journal of the Society for Conservation Biology.

[6]  R. Boonstra,et al.  Assessing the impact of live-capture, confinement, and translocation on stress and fate in eastern gray squirrels , 2013 .

[7]  David B. Lindenmayer,et al.  Counting the books while the library burns: why conservation monitoring programs need a plan for action , 2013 .

[8]  G. Mastromonaco,et al.  Influence of adrenocorticotrophin hormone challenge and external factors (age, sex, and body region) on hair cortisol concentration in Canada lynx (Lynx canadensis). , 2013, General and comparative endocrinology.

[9]  D. Sol,et al.  Do smart birds stress less? An interspecific relationship between brain size and corticosterone levels , 2013, Proceedings of the Royal Society B: Biological Sciences.

[10]  L. Romero,et al.  A consensus endocrine profile for chronically stressed wild animals does not exist. , 2013, General and comparative endocrinology.

[11]  Erin H. Strasser,et al.  Reproductive failure of a human-tolerant species, the American kestrel, is associated with stress and human disturbance , 2013 .

[12]  M. Humphries,et al.  Density Triggers Maternal Hormones That Increase Adaptive Offspring Growth in a Wild Mammal , 2013, Science.

[13]  Jessica L. Blickley,et al.  Effects of experimentally elevated traffic noise on nestling white-crowned sparrow stress physiology, immune function and life history , 2013, Journal of Experimental Biology.

[14]  R. Fleischer,et al.  Conservation outside Protected Areas and the Effect of Human‐Dominated Landscapes on Stress Hormones in Savannah Elephants , 2013, Conservation biology : the journal of the Society for Conservation Biology.

[15]  E. Werner,et al.  Stress hormones mediate predator-induced phenotypic plasticity in amphibian tadpoles , 2013, Proceedings of the Royal Society B: Biological Sciences.

[16]  K. Webster,et al.  Faecal glucocorticoid metabolite concentrations in the free-ranging bandicoots (Perameles nasuta and Isoodon obesulus) of northern Sydney , 2013 .

[17]  N. Selva,et al.  Concentration of fecal cortisol metabolites in chamois in relation to tourist pressure in Tatra National Park (South Poland) , 2013, Acta Theriologica.

[18]  C. Franklin,et al.  What is conservation physiology? Perspectives on an increasingly integrated and essential science , 2013, Conservation physiology.

[19]  S. Wasser,et al.  Effects of Exposure, Diet, and Thermoregulation on Fecal Glucocorticoid Measures in Wild Bears , 2013, PloS one.

[20]  R. Boonstra,et al.  Evaluating stress in natural populations of vertebrates: total CORT is not good enough , 2013 .

[21]  T. Jessop,et al.  Life history and the ecology of stress: how do glucocorticoid hormones influence life‐history variation in animals? , 2013 .

[22]  R. Boonstra.  Reality as the leading cause of stress: rethinking the impact of chronic stress in nature , 2013 .

[23]  Richard J. Williams,et al.  The stress response of three-spined sticklebacks is modified in proportion to effluent exposure downstream of wastewater treatment works. , 2013, Aquatic toxicology.

[24]  J. Cockrem.  Individual variation in glucocorticoid stress responses in animals. , 2013, General and comparative endocrinology.

[25]  Alan H. Krakauer,et al.  Experimental Chronic Noise Is Related to Elevated Fecal Corticosteroid Metabolites in Lekking Male Greater Sage-Grouse (Centrocercus urophasianus) , 2012, PloS one.

[26]  R. D. de Paula,et al.  Adrenal activity in maned wolves is higher on farmlands and park boundaries than within protected areas. , 2012, General and comparative endocrinology.

[27]  J. Atwell,et al.  Boldness behavior and stress physiology in a novel urban environment suggest rapid correlated evolutionary adaptation. , 2012, Behavioral ecology : official journal of the International Society for Behavioral Ecology.

[28]  W. Goymann.  On the use of non‐invasive hormone research in uncontrolled, natural environments: the problem with sex, diet, metabolic rate and the individual , 2012 .

[29]  Jerrold S. Meyer,et al.  Minireview: Hair cortisol: a novel biomarker of hypothalamic-pituitary-adrenocortical activity. , 2012, Endocrinology.

[30]  J. Ouyang,et al.  Corticosterone and brood abandonment in a passerine bird , 2012, Animal Behaviour.

[31]  Jessica L. Blickley,et al.  Experimental Evidence for the Effects of Chronic Anthropogenic Noise on Abundance of Greater Sage‐Grouse at Leks , 2012, Conservation biology : the journal of the Society for Conservation Biology.

[32]  R. Palme,et al.  Hair cortisol: a parameter of chronic stress? Insights from a radiometabolism study in guinea pigs , 2012, Journal of Comparative Physiology B.

[33]  F. Bonier.  Hormones in the city: Endocrine ecology of urban birds , 2012, Hormones and Behavior.

[34]  S. Creel,et al.  Effects of supplemental feeding and aggregation on fecal glucocorticoid metabolite concentrations in elk , 2012 .

[35]  C. Krebs,et al.  Mountain‐top and valley‐bottom experiences: the stress axis as an integrator of environmental variability in arctic ground squirrel populations , 2012 .

[36]  S. Juliano,et al.  Embryonic exposure to corticosterone modifies the juvenile stress response, oxidative stress and telomere length , 2011, Proceedings of the Royal Society B: Biological Sciences.

[37]  J. Ouyang,et al.  Within seasons and among years: When are corticosterone levels repeatable? , 2011, Hormones and Behavior.

[38]  R. Boonstra,et al.  How does diet affect fecal steroid hormone metabolite concentrations? An experimental examination in red squirrels. , 2011, General and comparative endocrinology.

[39]  Donald McKenzie,et al.  Managing uncertainty in climate‐driven ecological models to inform adaptation to climate change , 2011 .

[40]  S. Wasser,et al.  Glucocorticosteroid concentrations in feces and hair of captive caribou and reindeer following adrenocorticotropic hormone challenge. , 2011, General and comparative endocrinology.

[41]  S. Wasser,et al.  Impacts of acute and long-term vehicle exposure on physiology and reproductive success of the northern spotted owl , 2011 .

[42]  A. Møller,et al.  A meta-analysis of glucocorticoids as modulators of oxidative stress in vertebrates , 2011, Journal of Comparative Physiology B.

[43]  J. Seckl,et al.  Glucocorticoids, prenatal stress and the programming of disease , 2011, Hormones and Behavior.

[44]  R. Boonstra,et al.  Measuring stress in wildlife: techniques for quantifying glucocorticoids , 2011, Oecologia.

[45]  C. Krebs,et al.  From process to pattern: how fluctuating predation risk impacts the stress axis of snowshoe hares during the 10-year cycle , 2011, Oecologia.

[46]  R. Ricklefs,et al.  Corticosterone, testosterone and life-history strategies of birds , 2010, Proceedings of the Royal Society B: Biological Sciences.

[47]  M. Wikelski,et al.  Stress physiology as a predictor of survival in Galapagos marine iguanas , 2010, Proceedings of the Royal Society B: Biological Sciences.

[48]  J. Drake,et al.  Early warning signals of extinction in deteriorating environments , 2010, Nature.

[49]  Wolfgang Viechtbauer,et al.  Conducting Meta-Analyses in R with the metafor Package , 2010 .

[50]  R. Boonstra,et al.  Indirect predator effects on clutch size and the cost of egg production. , 2010, Ecology letters.

[51]  C. M. Coppens,et al.  Neuroendocrinology of coping styles: Towards understanding the biology of individual variation , 2010, Frontiers in Neuroendocrinology.

[52]  S. Cooke,et al.  Making conservation physiology relevant to policy makers and conservation practitioners , 2010 .

[53]  M. Humphries,et al.  Fecal cortisol metabolite levels in free-ranging North American red squirrels: Assay validation and the effects of reproductive condition. , 2010, General and comparative endocrinology.

[54]  C. Krebs,et al.  Assessing stress in animal populations: Do fecal and plasma glucocorticoids tell the same story? , 2010, General and comparative endocrinology.

[55]  G. Gabrielsen,et al.  Adrenocortical function of Arctic-breeding glaucous gulls in relation to persistent organic pollutants. , 2010, General and comparative endocrinology.

[56]  J. Wingfield,et al.  What is in a name? Integrating homeostasis, allostasis and stress , 2010, Hormones and Behavior.

[57]  Sharon E. Lynn,et al.  A single exposure to an acute stressor has lasting consequences for the hypothalamo-pituitary-adrenal response to stress in free-living birds. , 2010, General and comparative endocrinology.

[58]  E. A. MacDougall-Shackleton,et al.  Stress, song and survival in sparrows , 2009, Biology Letters.

[59]  D. Busch,et al.  Stress in a conservation context: A discussion of glucocorticoid actions and how levels change with conservation-relevant variables , 2009 .

[60]  Todd J. Brinkman,et al.  Evaluating Ungulate Mortality Associated With Helicopter Net-Gun Captures in the Northern Great Plains , 2009 .

[61]  I. Dunn,et al.  Chronic Stress Alters Glucocorticoid Receptor and Mineralocorticoid Receptor mRNA Expression in the European Starling (Sturnus vulgaris) Brain , 2009, Journal of neuroendocrinology.

[62]  Paul R. Martin,et al.  The relationship between fitness and baseline glucocorticoids in a passerine bird. , 2009, General and comparative endocrinology.

[63]  Lynn B. Martin.  Stress and immunity in wild vertebrates: timing is everything. , 2009, General and comparative endocrinology.

[64]  E. D. Kirby,et al.  Stress increases putative gonadotropin inhibitory hormone and decreases luteinizing hormone in male rats , 2009, Proceedings of the National Academy of Sciences.

[65]  F. Dhabhar.  Enhancing versus Suppressive Effects of Stress on Immune Function: Implications for Immunoprotection and Immunopathology , 2009, Neuroimmunomodulation.

[66]  L. Romero,et al.  Identifying hormonal habituation in field studies of stress. , 2009, General and comparative endocrinology.

[67]  R. Boonstra,et al.  Assessment of the Stress Response in Columbian Ground Squirrels: Laboratory and Field Validation of an Enzyme Immunoassay for Fecal Cortisol Metabolites , 2009, Physiological and Biochemical Zoology.

[68]  L. Romero,et al.  The reactive scope model — A new model integrating homeostasis, allostasis, and stress , 2009, Hormones and Behavior.

[69]  Christopher C. Wilmers,et al.  Human predators outpace other agents of trait change in the wild , 2009, Proceedings of the National Academy of Sciences.

[70]  L. Romero,et al.  Fecal glucocorticoid metabolites of experimentally stressed captive and free-living starlings: implications for conservation research. , 2008, General and comparative endocrinology.

[71]  T. Hahn,et al.  In search of relationships between the acute adrenocortical response and fitness. , 2008, General and comparative endocrinology.

[72]  A. Douglas,et al.  Adaptive Responses of the Maternal Hypothalamic‐Pituitary‐Adrenal Axis during Pregnancy and Lactation , 2008, Journal of neuroendocrinology.

[73]  H. Wada,et al.  Glucocorticoids: mediators of vertebrate ontogenetic transitions. , 2008, General and comparative endocrinology.

[74]  J. Wingfield,et al.  Seasonal glucocorticoid responses to capture in wild free-living mammals. , 2008, American journal of physiology. Regulatory, integrative and comparative physiology.

[75]  A. Hendry,et al.  Human influences on rates of phenotypic change in wild animal populations , 2008, Molecular ecology.

[76]  J. C. Serio‐Silva,et al.  Effects of forest fragmentation on the physiological stress response of black howler monkeys , 2007 .

[77]  T. Ellis,et al.  Measurement of fish steroids in water--a review. , 2007, General and comparative endocrinology.

[78]  J. Blas,et al.  Stress response during development predicts fitness in a wild, long lived vertebrate , 2007, Proceedings of the National Academy of Sciences.

[79]  P. Seddon,et al.  Elevated hormonal stress response and reduced reproductive output in Yellow-eyed penguins exposed to unregulated tourism. , 2007, General and comparative endocrinology.

[80]  M. Schaub,et al.  Spreading free-riding snow sports represent a novel serious threat for wildlife , 2007, Proceedings of the Royal Society B: Biological Sciences.

[81]  D. Nussey,et al.  The evolutionary ecology of individual phenotypic plasticity in wild populations , 2007, Journal of evolutionary biology.

[82]  I. Barja,et al.  Stress physiological responses to tourist pressure in a wild population of European pine marten , 2007, The Journal of Steroid Biochemistry and Molecular Biology.

[83]  D. Blumstein,et al.  Evaluating methods to quantify anthropogenic stressors on wild animals , 2007 .

[84]  J. Rivier,et al.  Astressin B, a corticotropin-releasing hormone receptor antagonist, accelerates the return to normal luteal function after an inflammatory-like stress challenge in the rhesus monkey. , 2007, Endocrinology.

[85]  P. Seddon,et al.  Physiological and reproductive consequences of human disturbance in Humboldt penguins: The need for species-specific visitor management , 2006 .

[86]  Nigel C. Bennett,et al.  Stress and the suppression of subordinate reproduction in cooperatively breeding meerkats , 2006, Proceedings of the National Academy of Sciences.

[87]  J. Partecke,et al.  Stress and the city: urbanization and its effects on the stress physiology in European blackbirds. , 2006, Ecology.

[88]  W. Goymann,et al.  Low ambient temperature increases food intake and dropping production, leading to incorrect estimates of hormone metabolite concentrations in European stonechats , 2006, Hormones and Behavior.

[89]  Friedrich Ladich,et al.  Ship noise and cortisol secretion in European freshwater fishes , 2006 .

[90]  J. Wingfield,et al.  Habituation of Adult Magellanic Penguins to Human Visitation as Expressed through Behavior and Corticosterone Secretion , 2006, Conservation biology : the journal of the Society for Conservation Biology.

[91]  J. Cockrem.  Conservation and behavioral neuroendocrinology , 2005, Hormones and Behavior.

[92]  A. K. Davis.  Effect of handling time and repeated sampling on avian white blood cell counts , 2005 .

[93]  R. Palme,et al.  Measuring Fecal Glucocorticoid Metabolites in Mammals and Birds: The Importance of Validation , 2005, Annals of the New York Academy of Sciences.

[94]  R. Palme.  Measuring Fecal Steroids: Guidelines for Practical Application , 2005, Annals of the New York Academy of Sciences.

[95]  R. Sapolsky.  The Influence of Social Hierarchy on Primate Health , 2005, Science.

[96]  R. Palme,et al.  Stress Hormones in Mammals and Birds: Comparative Aspects Regarding Metabolism, Excretion, and Noninvasive Measurement in Fecal Samples , 2005, Annals of the New York Academy of Sciences.

[97]  J. Wingfield,et al.  The Darwinian concept of stress: benefits of allostasis and costs of allostatic load and the trade-offs in health and disease , 2005, Neuroscience & Biobehavioral Reviews.

[98]  S. Merino,et al.  Haematological variables are good predictors of recruitment in nestling pied flycatchers (Ficedula hypoleuca) , 2005 .

[99]  J. Wingfield,et al.  Balancing food and predator pressure induces chronic stress in songbirds , 2004, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[100]  R. J. Putman,et al.  Supplementary winter feeding of wild red deer Cervus elaphus in Europe and North America: justifications, feeding practice and effectiveness , 2004 .

[101]  J. Millspaugh,et al.  Use of fecal glucocorticoid metabolite measures in conservation biology research: considerations for application and interpretation. , 2004, General and comparative endocrinology.

[102]  M. Wikelski,et al.  Exposure to ecotourism reduces survival and affects stress response in hoatzin chicks (Opisthocomus hoazin) , 2004 .

[103]  J. Wingfield,et al.  Role of the Low‐Affinity Glucocorticoid Receptor in the Regulation of Behavior and Energy Metabolism in the Migratory Red Knot Calidris canutus islandica , 2004, Physiological and Biochemical Zoology.

[104]  L. Romero,et al.  Physiological stress in ecology: lessons from biomedical research. , 2004, Trends in ecology & evolution.

[105]  R. Boonstra.  Coping with Changing Northern Environments: The Role of the Stress Axis in Birds and Mammals1 , 2004, Integrative and comparative biology.

[106]  K. Buchanan,et al.  Noninvasive endocrine data for behavioural studies: the importance of validation , 2004, Animal Behaviour.

[107]  J. Wingfield,et al.  Reproduction and Resistance to Stress: When and How , 2003, Journal of neuroendocrinology.

[108]  K. Hackländer,et al.  Reproductive suppression in female Alpine marmots, Marmota marmota , 2003, Animal Behaviour.

[109]  J. Millspaugh,et al.  Within-sample variation of fecal glucocorticoid measurements. , 2003, General and comparative endocrinology.

[110]  K. Erikstad,et al.  Reduced immunocompetence and cost of reproduction in common eiders , 2003, Oecologia.

[111]  J. Wingfield,et al.  The concept of allostasis in biology and biomedicine , 2003, Hormones and Behavior.

[112]  I. Moore,et al.  Stress, reproduction, and adrenocortical modulation in amphibians and reptiles , 2003, Hormones and Behavior.

[113]  L. Romero.  Seasonal changes in plasma glucocorticoid concentrations in free-living vertebrates. , 2002, General and comparative endocrinology.

[114]  J. Millspaugh,et al.  Effects of simulated environmental conditions on glucocorticoid metabolite measurements in white-tailed deer feces. , 2002, General and comparative endocrinology.

[115]  M. Wikelski,et al.  Galapagos Islands: Marine iguanas die from trace oil pollution , 2002, Nature.

[116]  Amanda R. Hardy,et al.  Snowmobile Activity and Glucocorticoid Stress Responses in Wolves and Elk , 2002 .

[117]  M. Rosenmann,et al.  HEMATOLOGICAL PARAMETERS AND STRESS INDEX IN RUFOUS-COLLARED SPARROWS DWELLING IN URBAN ENVIRONMENTS , 2002 .

[118]  H. Hofer,et al.  Social, state-dependent and environmental modulation of faecal corticosteroid levels in free-ranging female spotted hyenas† , 2001, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[119]  S. Austad,et al.  Effect of capture and season on fecal glucocorticoid levels in deer mice (Peromyscus maniculatus) and red-backed voles (Clethrionomys gapperi). , 2001, General and comparative endocrinology.

[120]  S. Creel,et al.  Social dominance and stress hormones , 2001 .

[121]  R. Boonstra,et al.  REPRODUCTION AT ALL COSTS: THE ADAPTIVE STRESS RESPONSE OF MALE ARCTIC GROUND SQUIRRELS , 2001 .

[122]  M. Wikelski,et al.  Corticosterone levels predict survival probabilities of Galápagos marine iguanas during El Niño events , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[123]  M. Wikelski,et al.  Marine Iguanas Oiled in the Galápagos , 2001, Science.

[124]  R. Sapolsky,et al.  How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions. , 2000, Endocrine reviews.

[125]  R. Sapolsky,et al.  Glucocorticoids, stress, and their adverse neurological effects: relevance to aging , 1999, Experimental Gerontology.

[126]  S. Nilsson,et al.  Interactions between methylsulfonyl PCBs and the glucocorticoid receptor. , 1998, Environmental health perspectives.

[127]  Grant R. Singleton,et al.  THE IMPACT OF PREDATOR-INDUCED STRESS ON THE SNOWSHOE HARE CYCLE , 1998 .

[128]  A. Convit,et al.  Cortisol levels during human aging predict hippocampal atrophy and memory deficits , 1998, Nature Neuroscience.

[129]  M. Baker,et al.  Physiological changes in brushtail possums, Trichosurus vulpecula, transferred from the wild to captivity. , 1998, The Journal of experimental zoology.

[130]  John C. Wingfield,et al.  ECOLOGICAL BASES OF HORMONE-BEHAVIOR INTERACTIONS : THE EMERGENCY LIFE HISTORY STAGE , 1998 .

[131]  F. Dhabhar,et al.  Acute Stress Enhances while Chronic Stress Suppresses Cell-Mediated Immunityin Vivo:A Potential Role for Leukocyte Trafficking , 1997, Brain, Behavior, and Immunity.

[132]  S. Wasser,et al.  Noninvasive Physiological Measures of Disturbance in the Northern Spotted Owl , 1997 .

[133]  M. Plummer,et al.  Chronology for Fluctuations in Late Pleistocene Sierra Nevada Glaciers and Lakes , 1996, Science.

[134]  R. Sapolsky.  Why Stress Is Bad for Your Brain , 1996, Science.

[135]  O. McGuinness,et al.  Role of cortisol in the metabolic response to stress hormone infusion in the conscious dog. , 1996, Metabolism: clinical and experimental.

[136]  A. Lecours,et al.  Longitudinal study of basal cortisol levels in healthy elderly subjects: Evidence for subgroups , 1996, Neurobiology of Aging.

[137]  R. Handa,et al.  Gonadal Steroid Hormone Receptors and Sex Differences in the Hypothalamo-Pituitary-Adrenal Axis , 1994, Hormones and Behavior.

[138]  E. Hellgren,et al.  Serum Chemistry and Hematology of Black Bears: Physiological Indices of Habitat Quality or Seasonal Patterns? , 1993 .

[139]  C. Audet,et al.  Impaired cortisol stress response in fish from environments polluted by PAHs, PCBs, and mercury , 1992, Archives of environmental contamination and toxicology.

[140]  J. Altmann,et al.  Incidence of hypercortisolism and dexamethasone resistance increases with age among wild baboons , 1991, Biological Psychiatry.

[141]  S. Rivest,et al.  Effect of stress on the activity of the hypothalamic-pituitary-gonadal axis: peripheral and central mechanisms. , 1991, Biology of reproduction.

[142]  C. Kirschbaum,et al.  Salivary cortisol in psychobiological research: an overview. , 1989, Neuropsychobiology.

[143]  B. Silverin.  Corticosterone-binding proteins and behavioral effects of high plasma levels of corticosterone during the breeding period in the pied flycatcher. , 1986, General and comparative endocrinology.

[144]  B. McEwen,et al.  The neuroendocrinology of stress and aging: the glucocorticoid cascade hypothesis. , 1986, Endocrine reviews.

[145]  R. Sapolsky,et al.  Stress-induced suppression of testicular function in the wild baboon: role of glucocorticoids. , 1985, Endocrinology.

[146]  B. McEwen,et al.  Glucocorticoid-sensitive hippocampal neurons are involved in terminating the adrenocortical stress response. , 1984, Proceedings of the National Academy of Sciences of the United States of America.

[147]  H. Selye.  A Syndrome produced by Diverse Nocuous Agents , 1936, Nature.

[148]  G. Zajicek,et al.  The Wisdom of the Body , 1934, Nature.

[149]  R Core Team,et al.  R: A language and environment for statistical computing. , 2014 .

[150]  N. Fefferman,et al.  Themed Issue Article: Stress in Vertebrates Can physiological stress alter population persistence? A model with conservation implications , 2013 .

[151]  K. Proffitt,et al.  Changes in Elk Distribution and Group Sizes after Wolf Restoration , 2012 .

[152]  N. Metcalfe,et al.  Oxidative stress as a mediator of life history trade-offs: mechanisms, measurements and interpretation. , 2009, Ecology letters.

[153]  R. Earley,et al.  Measuring water-borne cortisol in convict cichlids (Amatitlania nigrofasciata): is the procedure a stressor? , 2008 .

[154]  Rui F. Oliveira,et al.  Non-invasive measurement of steroids in fish-holding water: important considerations when applying the procedure to behaviour studies , 2008 .

[155]  P. Monaghan,et al.  Do telomere dynamics link lifestyle and lifespan? , 2006, Trends in ecology & evolution.

[156]  Evangelia Charmandari,et al.  Endocrinology of the stress response. , 2005, Annual review of physiology.

[157]  J. Reed,et al.  Collecting baseline corticosterone samples in the field: is under 3 min good enough? , 2005, Comparative biochemistry and physiology. Part A, Molecular & integrative physiology.

[158]  T. von Zglinicki.  Oxidative stress shortens telomeres. , 2002, Trends in biochemical sciences.

[159]  M. Meaney,et al.  Maternal care, gene expression, and the transmission of individual differences in stress reactivity across generations. , 2001, Annual review of neuroscience.

[160]  D. Delehanty,et al.  Circulating prolactin of incubating male Wilson's Phalaropes corresponds to clutch size and environmental stress , 1997 .

[161]  L. Hedges,et al.  Meta-analysis: Combining the results of independent experiments , 1993 .

[162]  J. G..  Animal Ecology and Evolution , 1931, Nature.

[163]  Naomi Wick,et al.  cranial capacity in mammals Anthropogenic environments exert variable selection on , 2013 .