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Ruf T, Bieber C. Why hibernate? Predator avoidance in the edible dormouse. MAMMAL RES 2022; 68:1-11. [PMID: 36624745 PMCID: PMC9816287 DOI: 10.1007/s13364-022-00652-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 09/29/2022] [Indexed: 01/12/2023]
Abstract
We address the question of ultimate selective advantages of hibernation. Biologists generally seem to accept the notion that multiday torpor is primarily a response to adverse environmental conditions, namely cold climate and low food abundance. We closely examine hibernation, and its summer equivalent estivation, in the edible dormouse, Glis glis. We conclude that in this species, hibernation is not primarily driven by poor conditions. Dormice enter torpor with fat reserves in years that are unfavourable for reproduction but provide ample food supply for animals to sustain themselves and even gain body energy reserves. While staying in hibernacula below ground, hibernators have much higher chances of survival than during the active season. We think that dormice enter prolonged torpor predominantly to avoid predation, mainly nocturnal owls. Because estivation in summer is immediately followed by hibernation, this strategy requires a good body condition in terms of fat reserves. As dormice age, they encounter fewer occasions to reproduce when calorie-rich seeds are available late in the year, and phase advance the hibernation season. By early emergence from hibernation, the best territories can be occupied and the number of mates maximised. However, this advantage comes at the cost of increased predation pressure that is maximal in spring. We argue the predator avoidance is generally one of the primary reasons for hibernation, as increased perceived predation pressure leads to an enhanced torpor use. The edible dormouse may be just an example where this behaviour becomes most obvious, on the population level and across large areas.
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Affiliation(s)
- Thomas Ruf
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstrasse 1, 1160 Vienna, Austria
| | - Claudia Bieber
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstrasse 1, 1160 Vienna, Austria
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2
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Hazan R, Schoemann M, Klutstein M. Endurance of extremely prolonged nutrient prevention across kingdoms of life. iScience 2021; 24:102745. [PMID: 34258566 PMCID: PMC8258982 DOI: 10.1016/j.isci.2021.102745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Numerous observations demonstrate that microorganisms can survive very long periods of nutrient deprivation and starvation. Moreover, it is evident that prolonged periods of starvation are a feature of many habitats, and many cells in all kingdoms of life are found in prolonged starvation conditions. Bacteria exhibit a range of responses to long-term starvation. These include genetic adaptations such as the long-term stationary phase and the growth advantage in stationary phase phenotypes characterized by mutations in stress-signaling genes and elevated mutation rates. Here, we suggest using the term "endurance of prolonged nutrient prevention" (EPNP phase), to describe this phase, which was also recently described in eukaryotes. Here, we review this literature and describe the current knowledge about the adaptations to very long-term starvation conditions in bacteria and eukaryotes, its conceptual and structural conservation across all kingdoms of life, and point out possible directions that merit further research.
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Affiliation(s)
- Ronen Hazan
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, P.O.B. 12272, Ein Kerem, Jerusalem 9112001, Israel
| | - Miriam Schoemann
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, P.O.B. 12272, Ein Kerem, Jerusalem 9112001, Israel
| | - Michael Klutstein
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, P.O.B. 12272, Ein Kerem, Jerusalem 9112001, Israel
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3
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Wilsterman K, Ballinger MA, Williams CM. A unifying, eco‐physiological framework for animal dormancy. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13718] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kathryn Wilsterman
- Biological Sciences University of Montana Missoula MT USA
- Integrative Biology University of California Berkeley CA USA
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4
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Ruf T, Bieber C. Physiological, Behavioral, and Life-History Adaptations to Environmental Fluctuations in the Edible Dormouse. Front Physiol 2020; 11:423. [PMID: 32431626 PMCID: PMC7214925 DOI: 10.3389/fphys.2020.00423] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 04/07/2020] [Indexed: 11/22/2022] Open
Abstract
The edible dormouse (Glis glis, formerly Myoxus glis) is a small arboreal mammal inhabiting deciduous forests in Europe. This rodent shows behavioral and physiological adaptations to three types of environmental fluctuations: (i) predictable seasonal variation in climate and food resources (ii) unpredictable year-to-year fluctuation in seed-production by trees and (iii) day-to-day variation in ambient temperature and precipitation. They cope with seasonally fluctuating conditions by seasonal fattening and hibernation. Dormice have adjusted to tree-mast fluctuations, i.e., pulsed resources, by sensing future seed availability in spring, and restricting reproduction to years with at least some seed production by beech and oak trees, which are a crucial food-resource for fast-growing juveniles in fall. Finally, dormice respond to short-term drops in ambient temperature by increased use of daily torpor as well as by huddling in groups of up to 24 conspecifics. These responses to environmental fluctuations strongly interact with each other: Dormice are much more prone to using daily torpor and huddling in non-reproductive years, because active gonads can counteract torpor and energy requirements for reproduction may prevent the sharing of food resources associated with huddling. Accordingly, foraging activity in fall is much more intense in reproductive mast years. Also, depending on their energy reserves, dormice may retreat to underground burrows in the summers of non-reproductive years, causing an extension of the hibernation season to up to 11.4 months. In addition to these interactions, responses to environmental fluctuations are modulated by the progression of life-history stages. With increasing age and diminishing chances of future reproduction, females reproduce with increasing frequency even under suboptimal environmental conditions. Simultaneously, older dormice shorten the hibernation season and phase-advance the emergence from hibernation in spring, apparently to occupy good breeding territories early, despite increased predation risk above ground. All of the above adaptions, i.e., huddling, torpor, hibernation, and reproduction skipping do not merely optimize energy-budgets but also help to balance individual predation risk against reproductive success, which adds another layer of complexity to the ability to make flexible adjustments in this species.
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Affiliation(s)
- Thomas Ruf
- Research Institute of Wildlife Ecology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Claudia Bieber
- Research Institute of Wildlife Ecology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine, Vienna, Austria
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5
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Saadeldin IM, Swelum AAA, Zakri AM, Tukur HA, Alowaimer AN. Effects of Acute Hyperthermia on the Thermotolerance of Cow and Sheep Skin-Derived Fibroblasts. Animals (Basel) 2020; 10:ani10040545. [PMID: 32218166 PMCID: PMC7222367 DOI: 10.3390/ani10040545] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 02/07/2023] Open
Abstract
Simple Summary We compared the thermotolerance of cow and sheep fibroblasts after exposure to acute hyperthermia (45 °C for 4 h). The primary culture, first passage, and cryopreserved cow fibroblasts resisted acute hyperthermia in terms of cell viability, proliferation, and migration to close cell scratch, in addition to increased expression of heat shock protein (HSP70 and HSP90) mRNA transcripts. Abstract This study was conducted to compare the effects of acute hyperthermia (45 °C for 4 h) on the viability, proliferation, and migratory activity through wound-healing assays of cow and sheep fibroblasts. The study examined the effects on primary cultures and first passage skin-derived fibroblasts. Relative quantification of HSP70, HSP90, P53, BAX, BCL2, and BECN1 was investigated after normalization to housekeeping genes GAPDH and beta-actin. The results revealed that cultured cow primary fibroblasts exhibited increased viability and reinitiated cell migration to close the cell monolayer scratch earlier than sheep cells. Similar patterns were observed in the first passage fibroblasts, with severe effects on sheep cells. Both cow and sheep cells exhibited decreased cell viability and failed to regain migratory activity after re-exposure of recovered heat-shocked cells. Effects of hyperthermia on sheep cells were potentiated by cell cryopreservation. The qPCR results showed that cow cells significantly increased HSP70 and HSP90 expression, which decreased the elevation of P53, and ameliorated the effects of the increased BAX/BCL2 ratio. The results provide a paradigm to compare thermotolerance among different animal species and revealed that trypsin could be an additional stress, which potentiates the effects of heat shock in in vitro experiments.
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Affiliation(s)
- Islam M Saadeldin
- Department of Animal Production, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
- Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt
| | - Ayman Abdel-Aziz Swelum
- Department of Animal Production, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
- Department of Theriogenology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44519, Egypt
| | - Adel M Zakri
- Plant Protection Department, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
| | - Hammed A Tukur
- Department of Animal Production, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
| | - Abdullah N Alowaimer
- Department of Animal Production, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
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6
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Regan JC, Froy H, Walling CA, Moatt JP, Nussey DH. Dietary restriction and insulin‐like signalling pathways as adaptive plasticity: A synthesis and re‐evaluation. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13418] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Jennifer C. Regan
- Institute of Immunology and Infection Research, School of Biological Sciences University of Edinburgh Edinburgh UK
| | - Hannah Froy
- Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
| | - Craig A. Walling
- Institute for Evolutionary Biology, School of Biological Sciences University of Edinburgh Edinburgh UK
| | - Joshua P. Moatt
- Institute for Evolutionary Biology, School of Biological Sciences University of Edinburgh Edinburgh UK
| | - Daniel H. Nussey
- Institute of Immunology and Infection Research, School of Biological Sciences University of Edinburgh Edinburgh UK
- Institute for Evolutionary Biology, School of Biological Sciences University of Edinburgh Edinburgh UK
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Abstract
While human hibernation would provide many advantages for medical applications and space exploration, the intrinsic risks of the procedure itself, as well as those involved if the procedure were to be misused, need to be assessed. Moreover, the distinctive brain state that is present during a hibernation-like state raises questions regarding the state of consciousness of the subject. Since, in animal studies, the cortical activity of this state differs from that of sleep, coma, or even general anesthesia, and resembles a sort of "slowed wakefulness", it is uncertain whether residual consciousness may still be present. In this review, I will present a brief summary of the literature on hibernation and of the current state of the art in inducing a state of artificial hibernation (synthetic torpor); I will then focus on the brain changes that are observed during hibernation, on how these could modify the neural substrate of consciousness, and on the possible use of hibernation as a model for quantum biology. Finally, some ethical considerations on the use of synthetic torpor technology will be presented.
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Affiliation(s)
- Matteo Cerri
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Piazza di Porta S.Donato, 2, 40126, Bologna, Italy. Tel.: +39 051 2091731; Fax: +39 051 2091737; E-mail:
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8
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Kordonowy L, MacManes M. Characterizing the reproductive transcriptomic correlates of acute dehydration in males in the desert-adapted rodent, Peromyscus eremicus. BMC Genomics 2017; 18:473. [PMID: 28645248 PMCID: PMC5481918 DOI: 10.1186/s12864-017-3840-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 06/02/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The understanding of genomic and physiological mechanisms related to how organisms living in extreme environments survive and reproduce is an outstanding question facing evolutionary and organismal biologists. One interesting example of adaptation is related to the survival of mammals in deserts, where extreme water limitation is common. Research on desert rodent adaptations has focused predominantly on adaptations related to surviving dehydration, while potential reproductive physiology adaptations for acute and chronic dehydration have been relatively neglected. This study aims to explore the reproductive consequences of acute dehydration by utilizing RNAseq data in the desert-specialized cactus mouse (Peromyscus eremicus). RESULTS We exposed 22 male cactus mice to either acute dehydration or control (fully hydrated) treatment conditions, quasimapped testes-derived reads to a cactus mouse testes transcriptome, and then evaluated patterns of differential transcript and gene expression. Following statistical evaluation with multiple analytical pipelines, nine genes were consistently differentially expressed between the hydrated and dehydrated mice. We hypothesized that male cactus mice would exhibit minimal reproductive responses to dehydration; therefore, this low number of differentially expressed genes between treatments aligns with current perceptions of this species' extreme desert specialization. However, these differentially expressed genes include Insulin-like 3 (Insl3), a regulator of male fertility and testes descent, as well as the solute carriers Slc45a3 and Slc38a5, which are membrane transport proteins that may facilitate osmoregulation. CONCLUSIONS These results suggest that in male cactus mice, acute dehydration may be linked to reproductive modulation via Insl3, but not through gene expression differences in the subset of other a priori tested reproductive hormones. Although water availability is a reproductive cue in desert-rodents exposed to chronic drought, potential reproductive modification via Insl3 in response to acute water-limitation is a result which is unexpected in an animal capable of surviving and successfully reproducing year-round without available external water sources. Indeed, this work highlights the critical need for integrative research that examines every facet of organismal adaptation, particularly in light of global climate change, which is predicted, amongst other things, to increase climate variability, thereby exposing desert animals more frequently to the acute drought conditions explored here.
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Affiliation(s)
- Lauren Kordonowy
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Rudman Hall (MCBS), 46 College Road, Durham, 03824 NH USA
| | - Matthew MacManes
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Rudman Hall (MCBS), 46 College Road, Durham, 03824 NH USA
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9
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Sisa C, Turroni S, Amici R, Brigidi P, Candela M, Cerri M. Potential role of the gut microbiota in synthetic torpor and therapeutic hypothermia. World J Gastroenterol 2017; 23:406-413. [PMID: 28210076 PMCID: PMC5291845 DOI: 10.3748/wjg.v23.i3.406] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 11/18/2016] [Accepted: 12/19/2016] [Indexed: 02/06/2023] Open
Abstract
Therapeutic hypothermia is today used in several clinical settings, among them the gut related diseases that are influenced by ischemia/reperfusion injury. This perspective paved the way to the study of hibernation physiology, in natural hibernators, highlighting an unexpected importance of the gut microbial ecosystem in hibernation and torpor. In natural hibernators, intestinal microbes adaptively reorganize their structural configuration during torpor, and maintain a mutualistic configuration regardless of long periods of fasting and cold temperatures. This allows the gut microbiome to provide the host with metabolites, which are essential to keep the host immunological and metabolic homeostasis during hibernation. The emerging role of the gut microbiota in the hibernation process suggests the importance of maintaining a mutualistic gut microbiota configuration in the application of therapeutic hypothermia as well as in the development of new strategy such as the use of synthetic torpor in humans. The possible utilization of tailored probiotics to mold the gut ecosystem during therapeutic hypothermia can also be taken into consideration as new therapeutic strategy.
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10
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Abstract
Autonomic thermoregulation is a recently acquired function, as it appears for the first time in mammals and provides the brain with the ability to control energy expenditure. The importance of such control can easily be highlighted by the ability of a heterogeneous group of mammals to actively reduce metabolic rate and enter a condition of regulated hypometabolism known as torpor. The central neural circuits of thermoregulatory cold defense have been recently unraveled and could in theory be exploited to reduce energy expenditure in species that do not normally use torpor, inducing a state called synthetic torpor. This approach may represent the first steps toward the development of a technology to induce a safe and reversible state of hypometabolism in humans, unlocking many applications ranging from new medical procedures to deep space travel.
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Affiliation(s)
- Matteo Cerri
- Department of Biomedical and Neuromotor Sciences, Physiology Division, Alma Mater Studiorum, University of Bologna, 40126 Bologna, Italy;
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11
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Wu CW, Storey KB. Life in the cold: links between mammalian hibernation and longevity. Biomol Concepts 2016; 7:41-52. [PMID: 26820181 DOI: 10.1515/bmc-2015-0032] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Accepted: 01/09/2016] [Indexed: 01/07/2023] Open
Abstract
The biological process of aging is the primary determinant of lifespan, but the factors that influence the rate of aging are not yet clearly understood and remain a challenging question. Mammals are characterized by >100-fold differences in maximal lifespan, influenced by relative variances in body mass and metabolic rate. Recent discoveries have identified long-lived mammalian species that deviate from the expected longevity quotient. A commonality among many long-lived species is the capacity to undergo metabolic rate depression, effectively re-programming normal metabolism in response to extreme environmental stress and enter states of torpor or hibernation. This stress tolerant phenotype often involves a reduction in overall metabolic rate to just 1-5% of the normal basal rate as well as activation of cytoprotective responses. At the cellular level, major energy savings are achieved via coordinated suppression of many ATP-expensive cell functions; e.g. global rates of protein synthesis are strongly reduced via inhibition of the insulin signaling axis. At the same time, various studies have shown activation of stress survival signaling during hibernation including up-regulation of protein chaperones, increased antioxidant defenses, and transcriptional activation of pro-survival signaling such as the FOXO and p53 pathways. Many similarities and parallels exist between hibernation phenotypes and different long-lived models, e.g. signal transduction pathways found to be commonly regulated during hibernation are also known to induce lifespan extension in animals such as Drosophila melanogaster and Caenorhabditis elegans. In this review, we highlight some of the molecular mechanisms that promote longevity in classic aging models C. elegans, Drosophila, and mice, while providing a comparative analysis to how they are regulated during mammalian hibernation.
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12
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Bondarenco A, Körtner G, Geiser F. How to keep cool in a hot desert: Torpor in two species of free-ranging bats in summer. Temperature (Austin) 2016; 3:476-483. [PMID: 28349087 PMCID: PMC5079220 DOI: 10.1080/23328940.2016.1214334] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 07/14/2016] [Accepted: 07/14/2016] [Indexed: 11/23/2022] Open
Abstract
Small insectivorous tree-roosting bats are among the most taxonomically diverse group of mammals in Australia's desert, yet little is known about their thermal physiology, torpor patterns and roosting ecology, especially during summer. We used temperature-telemetry to quantify and compare thermal biology and roost selection by broad-nosed bats Scotorepens greyii (6.3 g; n = 11) and Scotorepens balstoni (9.9 g; n = 5) in Sturt National Park (NSW Australia) over 3 summers (2010-13). Both vespertilionids used torpor often and the total time bats spent torpid was ∼7 h per day. Bats rewarmed using entirely passive rewarming on 44.8% (S. greyii) and 29.4% (S. balstoni) of all torpor arousals. Both bat species roosted in hollow, cracked dead trees relatively close to the ground (∼3 m) in dense tree stands. Our study shows that torpor and passive rewarming are 2 common and likely crucial survival traits of S. greyii and S. balstoni.
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Affiliation(s)
- Artiom Bondarenco
- Centre for Behavioural and Physiological Ecology, Zoology, University of New England, Armidale NSW, Australia
| | - Gerhard Körtner
- Centre for Behavioural and Physiological Ecology, Zoology, University of New England, Armidale NSW, Australia
| | - Fritz Geiser
- Centre for Behavioural and Physiological Ecology, Zoology, University of New England, Armidale NSW, Australia
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13
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Abstract
Extended bouts of fasting are ingrained in the ecology of many organisms, characterizing aspects of reproduction, development, hibernation, estivation, migration, and infrequent feeding habits. The challenge of long fasting episodes is the need to maintain physiological homeostasis while relying solely on endogenous resources. To meet that challenge, animals utilize an integrated repertoire of behavioral, physiological, and biochemical responses that reduce metabolic rates, maintain tissue structure and function, and thus enhance survival. We have synthesized in this review the integrative physiological, morphological, and biochemical responses, and their stages, that characterize natural fasting bouts. Underlying the capacity to survive extended fasts are behaviors and mechanisms that reduce metabolic expenditure and shift the dependency to lipid utilization. Hormonal regulation and immune capacity are altered by fasting; hormones that trigger digestion, elevate metabolism, and support immune performance become depressed, whereas hormones that enhance the utilization of endogenous substrates are elevated. The negative energy budget that accompanies fasting leads to the loss of body mass as fat stores are depleted and tissues undergo atrophy (i.e., loss of mass). Absolute rates of body mass loss scale allometrically among vertebrates. Tissues and organs vary in the degree of atrophy and downregulation of function, depending on the degree to which they are used during the fast. Fasting affects the population dynamics and activities of the gut microbiota, an interplay that impacts the host's fasting biology. Fasting-induced gene expression programs underlie the broad spectrum of integrated physiological mechanisms responsible for an animal's ability to survive long episodes of natural fasting.
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Affiliation(s)
- Stephen M Secor
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA
| | - Hannah V Carey
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin, USA
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14
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Abstract
Many environmental conditions can constrain the ability of animals to obtain sufficient food energy, or transform that food energy into useful chemical forms. To survive extended periods under such conditions animals must suppress metabolic rate to conserve energy, water, or oxygen. Amongst small endotherms, this metabolic suppression is accompanied by and, in some cases, facilitated by a decrease in core body temperature-hibernation or daily torpor-though significant metabolic suppression can be achieved even with only modest cooling. Within some ectotherms, winter metabolic suppression exceeds the passive effects of cooling. During dry seasons, estivating ectotherms can reduce metabolism without changes in body temperature, conserving energy reserves, and reducing gas exchange and its inevitable loss of water vapor. This overview explores the similarities and differences of metabolic suppression among these states within adult animals (excluding developmental diapause), and integrates levels of organization from the whole animal to the genome, where possible. Several similarities among these states are highlighted, including patterns and regulation of metabolic balance, fuel use, and mitochondrial metabolism. Differences among models are also apparent, particularly in whether the metabolic suppression is intrinsic to the tissue or depends on the whole-animal response. While in these hypometabolic states, tissues from many animals are tolerant of hypoxia/anoxia, ischemia/reperfusion, and disuse. These natural models may, therefore, serve as valuable and instructive models for biomedical research.
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Affiliation(s)
- James F Staples
- Department of Biology, University of Western Ontario, London, Ontario, Canada
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15
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Frey JK. Variation in phenology of hibernation and reproduction in the endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus). PeerJ 2015; 3:e1138. [PMID: 26290794 PMCID: PMC4540022 DOI: 10.7717/peerj.1138] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 07/09/2015] [Indexed: 12/02/2022] Open
Abstract
Hibernation is a key life history feature that can impact many other crucial aspects of a species’ biology, such as its survival and reproduction. I examined the timing of hibernation and reproduction in the federally endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus), which occurs across a broad range of latitudes and elevations in the American Southwest. Data from museum specimens and field studies supported predictions for later emergence and shorter active intervals in montane populations relative to lower elevation valley populations. A low-elevation population located at Bosque del Apache National Wildlife Refuge (BANWR) in the Rio Grande valley was most similar to other subspecies of Z. hudsonius: the first emergence date was in mid-May and there was an active interval of 162 days. In montane populations of Z. h. luteus, the date of first emergence was delayed until mid-June and the active interval was reduced to ca 124–135 days, similar to some populations of the western jumping mouse (Z. princeps). Last date of immergence into hibernation occurred at about the same time in all populations (mid to late October). In montane populations pregnant females are known from July to late August and evidence suggests that they have a single litter per year. At BANWR two peaks in reproduction were expected based on similarity of active season to Z. h. preblei. However, only one peak was clearly evident, possibly due to later first reproduction and possible torpor during late summer. At BANWR pregnant females are known from June and July. Due to the short activity season and geographic variation in phenology of key life history events of Z. h. luteus, recommendations are made for the appropriate timing for surveys for this endangered species.
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Affiliation(s)
- Jennifer K Frey
- Department of Fish, Wildlife, and Conservation Ecology, New Mexico State University , Las Cruces, NM , United States of America
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16
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Malan A. The Evolution of Mammalian Hibernation: Lessons from Comparative Acid-Base Physiology. Integr Comp Biol 2014; 54:484-96. [DOI: 10.1093/icb/icu002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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17
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Muñoz-Garcia A, Ben-Hamo M, Korine C, Pinshow B, Williams JB. A new thermoregulatory index for heterothermy. Methods Ecol Evol 2013. [DOI: 10.1111/2041-210x.12131] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Agustí Muñoz-Garcia
- Department of Evolution; Ecology and Organismal Biology; Ohio State University, Aronoff Laboratory; 318 W 12th Ave., Columbus, OH 43210 USA
| | - Miriam Ben-Hamo
- Mitrani Department of Desert Ecology; Jacob blaustein Institutes for desert Research; Ben-Gurion University of the Negev 84900 Midreshet Ben-Gurion Israel
| | - Carmi Korine
- Mitrani Department of Desert Ecology; Jacob blaustein Institutes for desert Research; Ben-Gurion University of the Negev 84900 Midreshet Ben-Gurion Israel
| | - Berry Pinshow
- Mitrani Department of Desert Ecology; Jacob blaustein Institutes for desert Research; Ben-Gurion University of the Negev 84900 Midreshet Ben-Gurion Israel
| | - Joseph B. Williams
- Department of Evolution; Ecology and Organismal Biology; Ohio State University, Aronoff Laboratory; 318 W 12th Ave., Columbus, OH 43210 USA
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