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Pettett CE, Salazar RD, Al-Hajri A, Al-Jabiri H, Macdonald DW, Yamaguchi N. Sex differences in the winter activity of desert hedgehogs (Paraechinus aethiopicus) in a resource-rich habitat in Qatar. Sci Rep 2022; 12:11118. [PMID: 35778424 PMCID: PMC9249915 DOI: 10.1038/s41598-022-15383-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 06/23/2022] [Indexed: 11/09/2022] Open
Abstract
Hedgehogs’ wide distribution and breadth of habitat use means they are a good model taxon for investigating behavioural responses to winter conditions, such as low temperatures and resource availability. We investigated the over-winter behaviour of desert hedgehogs (Paraechinus aethiopicus) in Qatar by radio-tracking 20 individuals and monitoring the body mass of 31 hedgehogs. Females spent more nights (38.63% of nights tracked) inactive than males (12.6%) and had lower monthly activity levels. The mean temperature on nights where hedgehogs were inactive was 14.9 °C compared with 17.0 °C when hedgehogs were active. By December, females lost a higher percentage of their November body mass than did males, but by February males had lost a higher percentage than females. We conclude that these sex differences in behaviour are a result of differing reproductive strategies with males becoming more active early in spring to search for mates, whereas female hedgehogs conserve energy for producing and raising young and avoid harassment by males. The winter activity of males may be facilitated by the resource-rich environment created by humans at this study site, and basking behaviour. This study highlights intraspecific and interspecific variation in behavioural strategies/tactics in response to winter conditions.
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Affiliation(s)
- Carly E Pettett
- WildCRU, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK
| | - Rosie D Salazar
- WildCRU, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK
| | - Afra Al-Hajri
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, PO Box 2713, Doha, Qatar
| | - Hayat Al-Jabiri
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, PO Box 2713, Doha, Qatar
| | - David W Macdonald
- WildCRU, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK
| | - Nobuyuki Yamaguchi
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, PO Box 2713, Doha, Qatar. .,Institute of Tropical Biodiversity and Sustainable Development, University of Malaysia Terengganu, 21030, Kuala Nerus, Malaysia.
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2
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Dissimilar use of an external heat source for thermoregulation by shrews from different geographic regions. J Therm Biol 2022; 104:103193. [DOI: 10.1016/j.jtherbio.2022.103193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 11/18/2022]
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3
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Genoud M. The seasonal variation of basal metabolic rate is related to the expression of torpor among small mammals. J Therm Biol 2022; 104:103197. [DOI: 10.1016/j.jtherbio.2022.103197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/18/2022] [Accepted: 01/21/2022] [Indexed: 10/19/2022]
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4
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Czenze ZJ, Dunbar M. Body mass affects short‐term heterothermy in Neotropical bats. Biotropica 2020. [DOI: 10.1111/btp.12807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zenon J. Czenze
- South African Research Chair in Conservation Physiology South African National Biodiversity Institute Pretoria South Africa
- Mammal Research Institute Department of Zoology and Entomology University of Pretoria Pretoria South Africa
| | - Miranda Dunbar
- Department of Biology Southern Connecticut State University New Haven CT USA
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5
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Geiser F. Seasonal Expression of Avian and Mammalian Daily Torpor and Hibernation: Not a Simple Summer-Winter Affair †. Front Physiol 2020; 11:436. [PMID: 32508673 PMCID: PMC7251182 DOI: 10.3389/fphys.2020.00436] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 04/08/2020] [Indexed: 12/17/2022] Open
Abstract
Daily torpor and hibernation (multiday torpor) are the most efficient means for energy conservation in endothermic birds and mammals and are used by many small species to deal with a number of challenges. These include seasonal adverse environmental conditions and low food/water availability, periods of high energetic demands, but also reduced foraging options because of high predation pressure. Because such challenges differ among regions, habitats and food consumed by animals, the seasonal expression of torpor also varies, but the seasonality of torpor is often not as clear-cut as is commonly assumed and differs between hibernators and daily heterotherms expressing daily torpor exclusively. Hibernation is found in mammals from all three subclasses from the arctic to the tropics, but is known for only one bird. Several hibernators can hibernate for an entire year or express torpor throughout the year (8% of species) and more hibernate from late summer to spring (14%). The most typical hibernation season is the cold season from fall to spring (48%), whereas hibernation is rarely restricted to winter (6%). In hibernators, torpor expression changes significantly with season, with strong seasonality mainly found in the sciurid and cricetid rodents, but seasonality is less pronounced in the marsupials, bats and dormice. Daily torpor is diverse in both mammals and birds, typically is not as seasonal as hibernation and torpor expression does not change significantly with season. Torpor in spring/summer has several selective advantages including: energy and water conservation, facilitation of reproduction or growth during development with limited resources, or minimisation of foraging and thus exposure to predators. When torpor is expressed in spring/summer it is usually not as deep and long as in winter, because of higher ambient temperatures, but also due to seasonal functional plasticity. Unlike many other species, subtropical nectarivorous blossom-bats and desert spiny mice use more frequent and pronounced torpor in summer than in winter, which is related to seasonal availability of nectar or water. Thus, seasonal use of torpor is complex and differs among species and habitats.
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Affiliation(s)
- Fritz Geiser
- Centre for Behavioural and Physiological Ecology, Zoology CO2, University of New England, Armidale, NSW, Australia
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6
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Nowack J, Levesque DL, Reher S, Dausmann KH. Variable Climates Lead to Varying Phenotypes: “Weird” Mammalian Torpor and Lessons From Non-Holarctic Species. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00060] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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7
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Boratyński JS, Iwińska K, Bogdanowicz W. An intra-population heterothermy continuum: notable repeatability of body temperature variation in food-deprived yellow-necked mice. ACTA ACUST UNITED AC 2019; 222:222/6/jeb197152. [PMID: 30877147 DOI: 10.1242/jeb.197152] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 02/11/2019] [Indexed: 11/20/2022]
Abstract
Theoretical modelling predicts that the thermoregulatory strategies of endothermic animals range from those represented by thermal generalists to those characteristic for thermal specialists. While the generalists tolerate wide variations in body temperature (T b), the specialists maintain T b at a more constant level. The model has gained support from inter-specific comparisons relating to species and population levels. However, little is known about consistent among-individual variation within populations that could be shaped by natural selection. We studied the consistency of individual heterothermic responses to environmental challenges in a single population of yellow-necked mice (Apodemus flavicollis), by verifying the hypothesis that T b variation is a repeatable trait. To induce the heterothermic response, the same individuals were repeatedly food deprived for 24 h. We measured T b with implanted miniaturised data loggers. Before each fasting experiment, we measured basal metabolic rate (BMR). Thus, we also tested whether individual variation of heterothermy correlates with individual self-maintenance costs, and the potential benefits arising from heterothermic responses that should correlate with body size/mass. We found that some individuals clearly entered torpor while others kept T b stable, and that there were also individuals that showed intermediate thermoregulatory patterns. Heterothermy was found to correlate negatively with body mass and slightly positively with the BMR achieved 1-2 days before fasting. Nonetheless, heterothermy was shown to be highly repeatable, irrespective of whether we controlled for self-maintenance costs and body size. Our results indicate that specialist and generalist thermoregulatory phenotypes can co-exist in a single population, creating a heterothermy continuum.
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Affiliation(s)
- Jan S Boratyński
- Mammal Research Institute, Polish Academy of Sciences, 17-230 Białowieża, Poland .,Museum and Institute of Zoology, Polish Academy of Sciences, 00-679 Warszawa, Poland
| | - Karolina Iwińska
- Institute of Biology, University of Białystok, 15-328 Białystok, Poland
| | - Wiesław Bogdanowicz
- Museum and Institute of Zoology, Polish Academy of Sciences, 00-679 Warszawa, Poland
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8
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Boratyński JS, Iwińska K, Bogdanowicz W. Body temperature variation in free-living and food-deprived yellow-necked mice sustains an adaptive framework for endothermic thermoregulation. MAMMAL RES 2018. [DOI: 10.1007/s13364-018-0392-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Blanco MB, Dausmann KH, Faherty SL, Yoder AD. Tropical heterothermy is “cool”: The expression of daily torpor and hibernation in primates. Evol Anthropol 2018; 27:147-161. [DOI: 10.1002/evan.21588] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 03/15/2018] [Indexed: 12/19/2022]
Affiliation(s)
| | | | | | - Anne D. Yoder
- Duke Lemur Center; Durham North Carolina
- Department of Biology; Duke University; Durham North Carolina
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More functions of torpor and their roles in a changing world. J Comp Physiol B 2017; 187:889-897. [PMID: 28432393 PMCID: PMC5486538 DOI: 10.1007/s00360-017-1100-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/26/2016] [Accepted: 02/26/2017] [Indexed: 02/06/2023]
Abstract
Increased winter survival by reducing energy expenditure in adult animals is often viewed as the primary function of torpor. However, torpor has many other functions that ultimately increase the survival of heterothermic mammals and birds. In this review, we summarize new findings revealing that animals use torpor to cope with the conditions during and after natural disasters, including fires, storms, and heat waves. Furthermore, we suggest that torpor, which also prolongs longevity and was likely crucial for survival of mammals during the time of the dinosaur extinctions, will be advantageous in a changing world. Climate change is assumed to lead to an increase in the occurrence and intensity of climatic disasters, such as those listed above and also abnormal floods, droughts, and extreme temperatures. The opportunistic use of torpor, found in many heterothermic species, will likely enhance survival of these challenges, because these species can reduce energy and foraging requirements. However, many strictly seasonal hibernators will likely face the negative consequences of the predicted increase in temperature, such as range contraction. Overall, available data suggest that opportunistic heterotherms with their flexible energy requirements have an adaptive advantage over homeotherms in response to unpredictable conditions.
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11
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Torpor patterns in common hamsters with and without access to food stores. J Comp Physiol B 2017; 187:881-888. [PMID: 28417150 PMCID: PMC5486536 DOI: 10.1007/s00360-017-1093-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 03/14/2017] [Accepted: 04/06/2017] [Indexed: 01/15/2023]
Abstract
Hibernating species significantly reduce energy expenditure during winter by entering torpor. Nevertheless, the various benefits of hibernation might be counteracted by negative effects of torpor such as immune depression, oxidative stress, or neuronal impairment. Considering these trade-offs, adequate energy reserves could allow animals to reduce the time spent in torpor or the extent of metabolic depression. Common hamsters use food stores during hibernation and previously documented high individual variations in body temperature patterns during winter could, therefore, be related to differences in external energy reserves. In this study, we manipulated the availability of food stores under laboratory conditions to investigate potential effects on hibernation patterns. Female hamsters were kept in artificial burrows in climate chambers and subcutaneous temperature was recorded using implanted data loggers. One group had access to large food stores, whereas another group received daily food portions which were removed on the next day if not consumed. Almost all hamsters without access to food stores hibernated, while less than half of the individuals with food stores entered deep torpor. Individuals without food hoards additionally expressed more short torpor bouts and exhibited lower minimum subcutaneous temperatures during torpor than those with food stores. Thus, individuals confronted with lacking food reserves were more likely to hibernate and additionally saved energy by entering short torpor bouts more frequently and remaining at lower subcutaneous temperature both during torpor and euthermic periods. In conclusion, our results demonstrate that food store availability affects torpor expression and also highlight variation in torpor patterns and energy-saving strategies in common hamsters.
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Boyles JG, Bennett NC, Mohammed OB, Alagaili AN. Torpor Patterns in Desert Hedgehogs (Paraechinus aethiopicus) Represent Another New Point along a Thermoregulatory Continuum. Physiol Biochem Zool 2017; 90:445-452. [PMID: 28402233 DOI: 10.1086/691542] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Documenting variation in thermoregulatory patterns across phylogenetically and geographically diverse taxa is key to understanding the evolution of endothermy and heterothermy in birds and mammals. We recorded body temperature (Tb) in free-ranging desert hedgehogs (Paraechinus aethiopicus) across three seasons in the deserts of Saudi Arabia. Modal Tb's (35°-36.5°C) were slightly below normal for mammals but still warmer than those of other hedgehogs. The single maximum Tb recorded was 39.2°C, which is cooler than maximum Tb's recorded in most desert mammals. Desert hedgehogs commonly used torpor during winter and spring but never during summer. Torpor bouts occurred frequently but irregularly, and most lasted less than 24 h. Unlike daily heterotherms, desert hedgehogs did occasionally remain torpid for more than 24 h, including one bout of 101 h. Body temperatures during torpor were often within 2°-3°C of ambient temperature; however, we never recorded repeated bouts of long, predictable torpor punctuated by brief arousal periods similar to those common among seasonal hibernators. Thus, desert hedgehogs can be included on the ever-growing list of species that display torpor patterns intermediate to traditionally defined hibernators and daily heterotherms. Extant hedgehogs are a recent radiation within an ancient family, and the intermediate thermoregulatory pattern displayed by desert hedgehogs is unlike the deeper and more regular torpor seen in other hedgehogs, suggesting that this may be a derived-as opposed to ancestral-trait in this subfamily. We suggest that this family (Erinaceidae) and order (Eulipotyphla) may be important for understanding the evolution of thermoregulatory patterns among Laurasiatheria and mammals in general.
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Affiliation(s)
- Justin G Boyles
- 1 Cooperative Wildlife Research Laboratory, Department of Zoology, Southern Illinois University, Carbondale, Illinois
| | - Nigel C Bennett
- 2 King Saud University Mammals Research Chair, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.,3 Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa
| | - Osama B Mohammed
- 2 King Saud University Mammals Research Chair, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Abdulaziz N Alagaili
- 2 King Saud University Mammals Research Chair, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
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13
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Levesque DL, Nowack J, Stawski C. Modelling mammalian energetics: the heterothermy problem. ACTA ACUST UNITED AC 2016. [DOI: 10.1186/s40665-016-0022-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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14
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Chayama Y, Ando L, Tamura Y, Miura M, Yamaguchi Y. Decreases in body temperature and body mass constitute pre-hibernation remodelling in the Syrian golden hamster, a facultative mammalian hibernator. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160002. [PMID: 27152216 PMCID: PMC4852639 DOI: 10.1098/rsos.160002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 03/08/2016] [Indexed: 06/02/2023]
Abstract
Hibernation is an adaptive strategy for surviving during periods with little or no food availability, by profoundly reducing the metabolic rate and the core body temperature (T b). Obligate hibernators (e.g. bears, ground squirrels, etc.) hibernate every winter under the strict regulation of endogenous circannual rhythms, and they are assumed to undergo adaptive remodelling in autumn, the pre-hibernation period, prior to hibernation. However, little is known about the nature of pre-hibernation remodelling. Syrian hamsters (Mesocricetus auratus) are facultative hibernators that can hibernate irrespective of seasons when exposed to prolonged short photoperiod and cold ambient temperature (SD-Cold) conditions. Their T b set point reduced by the first deep torpor (DT) and then increased gradually after repeated cycles of DT and periodic arousal (PA), and finally recovered to the level observed before the prolonged SD-Cold in the post-hibernation period. We also found that, before the initiation of hibernation, the body mass of animals decreased below a threshold, indicating that hibernation in this species depends on body condition. These observations suggest that Syrian hamsters undergo pre-hibernation remodelling and that T b and body mass can be useful physiological markers to monitor the remodelling process during the pre-hibernation period.
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Affiliation(s)
- Yuichi Chayama
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Lisa Ando
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yutaka Tamura
- Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama 729-0292, Japan
| | - Masayuki Miura
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Yoshifumi Yamaguchi
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Chiyoda-ku, Tokyo 102-0076, Japan
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15
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Ruf T, Geiser F. Daily torpor and hibernation in birds and mammals. Biol Rev Camb Philos Soc 2015; 90:891-926. [PMID: 25123049 PMCID: PMC4351926 DOI: 10.1111/brv.12137] [Citation(s) in RCA: 484] [Impact Index Per Article: 53.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 07/16/2014] [Accepted: 07/16/2014] [Indexed: 12/11/2022]
Abstract
Many birds and mammals drastically reduce their energy expenditure during times of cold exposure, food shortage, or drought, by temporarily abandoning euthermia, i.e. the maintenance of high body temperatures. Traditionally, two different types of heterothermy, i.e. hypometabolic states associated with low body temperature (torpor), have been distinguished: daily torpor, which lasts less than 24 h and is accompanied by continued foraging, versus hibernation, with torpor bouts lasting consecutive days to several weeks in animals that usually do not forage but rely on energy stores, either food caches or body energy reserves. This classification of torpor types has been challenged, suggesting that these phenotypes may merely represent extremes in a continuum of traits. Here, we investigate whether variables of torpor in 214 species (43 birds and 171 mammals) form a continuum or a bimodal distribution. We use Gaussian-mixture cluster analysis as well as phylogenetically informed regressions to quantitatively assess the distinction between hibernation and daily torpor and to evaluate the impact of body mass and geographical distribution of species on torpor traits. Cluster analysis clearly confirmed the classical distinction between daily torpor and hibernation. Overall, heterothermic endotherms tend to be small; hibernators are significantly heavier than daily heterotherms and also are distributed at higher average latitudes (∼35°) than daily heterotherms (∼25°). Variables of torpor for an average 30 g heterotherm differed significantly between daily heterotherms and hibernators. Average maximum torpor bout duration was >30-fold longer, and mean torpor bout duration >25-fold longer in hibernators. Mean minimum body temperature differed by ∼13°C, and the mean minimum torpor metabolic rate was ∼35% of the basal metabolic rate (BMR) in daily heterotherms but only 6% of BMR in hibernators. Consequently, our analysis strongly supports the view that hibernators and daily heterotherms are functionally distinct groups that probably have been subject to disruptive selection. Arguably, the primary physiological difference between daily torpor and hibernation, which leads to a variety of derived further distinct characteristics, is the temporal control of entry into and arousal from torpor, which is governed by the circadian clock in daily heterotherms, but apparently not in hibernators.
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Affiliation(s)
- Thomas Ruf
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Savoyenstraße 1, A-1160 Vienna, Austria
- Centre for Behavioural and Physiological Ecology, Zoology, University of New England, Armidale, New South Wales 2351, Australia
| | - Fritz Geiser
- Centre for Behavioural and Physiological Ecology, Zoology, University of New England, Armidale, New South Wales 2351, Australia
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Affiliation(s)
- Julia Nowack
- Department of Animal Ecology and Conservation; Biocentre Grindel; University of Hamburg; Martin-Luther-King Platz 3 20146 Hamburg Germany
- Centre for Behavioural and Physiological Ecology, Zoology; University of New England; Armidale NSW 2351 Australia
| | - Kathrin H. Dausmann
- Department of Animal Ecology and Conservation; Biocentre Grindel; University of Hamburg; Martin-Luther-King Platz 3 20146 Hamburg Germany
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17
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Magnitude of food overabundance affects expression of daily torpor. Physiol Behav 2015; 139:519-23. [DOI: 10.1016/j.physbeh.2014.12.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 11/26/2014] [Accepted: 12/03/2014] [Indexed: 11/23/2022]
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McAllan BM, Geiser F. Torpor during reproduction in mammals and birds: dealing with an energetic conundrum. Integr Comp Biol 2014; 54:516-32. [PMID: 24973362 DOI: 10.1093/icb/icu093] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Torpor and reproduction in mammals and birds are widely viewed as mutually exclusive processes because of opposing energetic and hormonal demands. However, the reported number of heterothermic species that express torpor during reproduction is ever increasing, to some extent because of recent work on free-ranging animals. We summarize current knowledge about those heterothermic mammals that do not express torpor during reproduction and, in contrast, examine those heterothermic birds and mammals that do use torpor during reproduction. Incompatibility between torpor and reproduction occurs mainly in high-latitude sciurid and cricetid rodents, which live in strongly seasonal, but predictably productive habitats in summer. In contrast, torpor during incubation, brooding, pregnancy, or lactation occurs in nightjars, hummingbirds, echidnas, several marsupials, tenrecs, hedgehogs, bats, carnivores, mouse lemurs, and dormice. Animals that enter torpor during reproduction often are found in unpredictable habitats, in which seasonal availability of food can be cut short by changes in weather, or are species that reproduce fully or partially during winter. Moreover, animals that use torpor during the reproductive period have relatively low reproductive costs, are largely insectivorous, carnivorous, or nectarivorous, and thus rely on food that can be unpredictable or strongly seasonal. These species with relatively unpredictable food supplies must gain an advantage by using torpor during reproduction because the main cost is an extension of the reproductive period; the benefit is increased survival of parent and offspring, and thus fitness.
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Affiliation(s)
- B M McAllan
- *Department of Physiology, School of Medical Sciences and Bosch Institute, The University of Sydney, Sydney, New South Wales 2006, Australia; Centre for Behavioural and Physiological Ecology, Department of Zoology, University of New England, Armidale, New South Wales 2351, Australia*Department of Physiology, School of Medical Sciences and Bosch Institute, The University of Sydney, Sydney, New South Wales 2006, Australia; Centre for Behavioural and Physiological Ecology, Department of Zoology, University of New England, Armidale, New South Wales 2351, Australia
| | - Fritz Geiser
- *Department of Physiology, School of Medical Sciences and Bosch Institute, The University of Sydney, Sydney, New South Wales 2006, Australia; Centre for Behavioural and Physiological Ecology, Department of Zoology, University of New England, Armidale, New South Wales 2351, Australia
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Kronfeld-Schor N, Dayan T. Thermal Ecology, Environments, Communities, and Global Change: Energy Intake and Expenditure in Endotherms. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2013. [DOI: 10.1146/annurev-ecolsys-110512-135917] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To survive, animals must maintain a balance between energy acquisition (foraging) and energy expenditure. This challenge is particularly great for endotherm vertebrates that require high amounts of energy to maintain homeothermy. Many of these endotherms use hibernation or daily torpor as a mechanism to reduce energy expenditure during anticipated or stochastic periods of stress. Although ecological researchers have focused extensively on energy acquisition, physiologists have largely studied thermal ecology and the mechanisms allowing endotherms to regulate energy expenditure, with little research explicitly linking ecology and thermal biology. Nevertheless, theoretical considerations and research conducted so far point to a significant ecological role for torpor in endotherms. Moreover, global-change challenges facing vertebrate endotherms are also considered in view of their ability to regulate their energy expenditure. We review the thermal ecology of endothermic vertebrates and some of its ecological and evolutionary implications.
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Affiliation(s)
| | - Tamar Dayan
- Department of Zoology, Tel Aviv University, Tel Aviv 69978, Israel;,
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Vuarin P, Dammhahn M, Henry P. Individual flexibility in energy saving: body size and condition constrain torpor use. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12069] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pauline Vuarin
- UMR 7179 CNRS‐MNHN 1 avenue du Petit Château 91800 Brunoy France
| | - Melanie Dammhahn
- Behavioral Ecology & Sociobiology Unit German Primate Center, Leibniz Institute for Primate Research Kellnerweg 4 37077 Göttingen Germany
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Boyles JG, Smit B, McKechnie AE. Variation in body temperature is related to ambient temperature but not experimental manipulation of insulation in two small endotherms with different thermoregulatory patterns. J Zool (1987) 2012. [DOI: 10.1111/j.1469-7998.2012.00909.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. G. Boyles
- Department of Zoology and Entomology; Mammal Research Institute; University of Pretoria; Pretoria; South Africa
| | - B. Smit
- Department of Zoology and Entomology; Mammal Research Institute; University of Pretoria; Pretoria; South Africa
| | - A. E. McKechnie
- Department of Zoology and Entomology; Mammal Research Institute; University of Pretoria; Pretoria; South Africa
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Boyles JG, Smit B, Sole CL, McKechnie AE. Body temperature patterns in two syntopic elephant shrew species during winter. Comp Biochem Physiol A Mol Integr Physiol 2012; 161:89-94. [DOI: 10.1016/j.cbpa.2011.09.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/16/2011] [Accepted: 09/19/2011] [Indexed: 11/24/2022]
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McKechnie AE, Mzilikazi N. Heterothermy in Afrotropical mammals and birds: a review. Integr Comp Biol 2011; 51:349-63. [PMID: 21705792 DOI: 10.1093/icb/icr035] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Recent years have seen a rapid increase in the number of Afrotropical endotherms known to avoid mismatches between energy supply and demand by using daily torpor and/or hibernation. Among mammals, heterothermy has been reported in 40 species in six orders, namely Macroscelidea, Afrosoricida, Rodentia, Eulipotyphla, Primates and Chiroptera. These species span a range in body mass of 7-770 g, with minimum heterothermic body temperatures ranging from 1-27°C and bout length varying from 1 h to 70 days. Daily torpor is the most common form of heterothermy, with true hibernation being observed in only seven species, Graphiurus murinus, Graphiurus ocularis, Atelerix frontalis, Cheirogaleus medius, Cheirogaleus major, Microcebus murinus and Microcebus griseorufus. The traditional distinction between daily torpor and hibernation is blurred in some species, with free-ranging individuals exhibiting bouts of > 24 h and body temperatures < 16 °C, but none of the classical behaviours associated with hibernation. Several species bask in the sun during rewarming. Among birds, heterothermy has been reported in 16 species in seven orders, and is more pronounced in phylogenetically older taxa. Both in mammals and birds, patterns of heterothermy can vary dramatically among species occurring at a particular site, and even among individuals of a single species. For instance, patterns of heterothermy among cheirogalid primates in western Madagascar vary from daily torpor to uninterrupted hibernation for up to seven months. Other examples of variation among closely-related species involve small owls, elephant shrews and vespertilionid bats. There may also be variation in terms of the ecological correlates of torpor within a species, as is the case in the Freckled Nightjar Caprimulgus tristigma.
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Affiliation(s)
- Andrew E McKechnie
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa.
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Lovegrove BG. The evolution of endothermy in Cenozoic mammals: a plesiomorphic-apomorphic continuum. Biol Rev Camb Philos Soc 2011; 87:128-62. [DOI: 10.1111/j.1469-185x.2011.00188.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Geiser F, Stawski C, Bondarenco A, Pavey CR. Torpor and activity in a free-ranging tropical bat: implications for the distribution and conservation of mammals? Naturwissenschaften 2011; 98:447-52. [DOI: 10.1007/s00114-011-0779-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Revised: 02/22/2011] [Accepted: 02/24/2011] [Indexed: 11/29/2022]
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