1
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Linek N, Yanco SW, Volkmer T, Zuñiga D, Wikelski M, Partecke J. Migratory lifestyle carries no added overall energy cost in a partial migratory songbird. Nat Ecol Evol 2024:10.1038/s41559-024-02545-y. [PMID: 39294404 DOI: 10.1038/s41559-024-02545-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 08/22/2024] [Indexed: 09/20/2024]
Abstract
Seasonal bird migration may provide energy benefits associated with moving to areas with less physiologically challenging climates or increased food availability, but migratory movements themselves may carry high costs. However, time-dynamic energy profiles of free-living migrants-especially small-bodied songbirds-are challenging to measure. Here we quantify energy output and thermoregulatory costs in partially migratory common blackbirds using implanted heart rate and temperature loggers paired with automated radio telemetry and energetic modelling. Our results show that blackbirds save considerable energy in preparation for migration by decreasing heart rate and body temperature 28 days before departure, potentially dwarfing the energy costs of migratory flights. Yet, in warmer wintering areas, migrants do not appear to decrease total daily energy expenditure despite a substantially reduced cost of thermoregulation. These findings indicate differential metabolic programmes across different wintering strategies despite equivalent overall energy expenditure, suggesting that the maintenance of migration is associated with differences in energy allocation rather than with total energy expenditure.
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Affiliation(s)
- Nils Linek
- Max Planck Institute of Animal Behavior, Radolfzell, Germany.
- Department of Biology, University of Konstanz, Konstanz, Germany.
| | - Scott W Yanco
- Center for Biodiversity and Global Change, Yale University, New Haven, CT, USA
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | - Tamara Volkmer
- Max Planck Institute of Animal Behavior, Radolfzell, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Daniel Zuñiga
- Max Planck Institute of Animal Behavior, Radolfzell, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Martin Wikelski
- Max Planck Institute of Animal Behavior, Radolfzell, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Jesko Partecke
- Max Planck Institute of Animal Behavior, Radolfzell, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
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2
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Matsumoto T, Iwata I, Sakamoto T, Hirata S. First noncontact millimeter-wave radar measurement of heart rate in great apes: Validation in chimpanzees (Pan troglodytes). Am J Primatol 2024; 86:e23633. [PMID: 38775638 DOI: 10.1002/ajp.23633] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 03/24/2024] [Accepted: 04/20/2024] [Indexed: 07/18/2024]
Abstract
Heart rate is a crucial vital sign and a valuable indicator for assessing the physical and psychological condition of a target animal. Heart rate contributes to (1) fundamental information for cognitive research, (2) an indicator of psychological and physical stress, and (3) improving the animal welfare of captive animals, especially in nonhuman primate studies. Heart rate has been measured using a contact-type device; however, the device burdens the target animals and that there are risks associated with anesthesia during installation. This study explores the application of heartbeat measurement techniques using millimeter-wave radar, primarily developed for humans, as a remote and noninvasive method for measuring the heart rate of nonhuman primates. Through a measurement test conducted on two chimpanzees, we observed a remarkable correspondence between the peak frequency spectrum of heart rate estimated using millimeter-wave radar and the mean value obtained from electrocardiograph data, thereby validating the accuracy of the method. To the best of our knowledge, this is the first demonstration of the precise measurement of great apes' heart rate using millimeter-wave radar technology. Compared to heart rate measurement using video analysis, the method using millimeter-wave radar has the advantage that it is less susceptible to weather and lighting conditions and that measurement techniques for multiple individuals have been developed for human subjects, while its disadvantage is that validation of measurement from long distances has not been completed. Another disadvantage common to both methods is that measurement becomes difficult when the movement of the target individual is large. The possibility of noncontact measurement of heart rate in wild and captive primates will undoubtedly open up a new research area while taking animal welfare into consideration.
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Affiliation(s)
- Takuya Matsumoto
- Department of Science, Shinshu University, Matsumoto, Nagano, Japan
| | - Itsuki Iwata
- Department of Electrical Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Kyoto, Japan
| | - Takuya Sakamoto
- Department of Electrical Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Kyoto, Japan
| | - Satoshi Hirata
- Kumamoto Sanctuary, Wildlife Research Center, Kyoto University, Uki, Kumamoto, Japan
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3
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Tan S, Li J, Chen J, Fu J. Context-dependent effects of thermal acclimation on physiological correlates of animal personality in Asiatic toads. Proc Biol Sci 2024; 291:20241012. [PMID: 39079664 PMCID: PMC11288686 DOI: 10.1098/rspb.2024.1012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/05/2024] [Accepted: 06/05/2024] [Indexed: 08/03/2024] Open
Abstract
Persistent individual variation in behaviour, or 'personality', is a widespread phenomenon in animals, and understanding the evolution of animal personality is a key task of current biology. Natural selection has been proposed to promote the integration of personality with animal 'intrinsic states', such as metabolic or endocrine traits, and this integration varies with ecological conditions. However, these external ecological modulatory effects have rarely been examined. Here, we investigate the effects of thermal acclimation on between-individual covariations between physiology and behaviour in Asiatic toads (Bufo gargarizans) along an altitudinal gradient. Our results reveal that the thermal modulatory effects on the covariations depend on the altitudinal population. Specifically, at low altitudes, between-individual covariations are highly plastic, with risk-taking behaviour covarying with baseline glucocorticoids (GCs) under warm acclimation, but risk-taking and exploration behaviour covarying with resting metabolic rate (RMR) under cold acclimation. In contrast, between-individual covariations are relatively fixed at high altitudes, with risk-taking behaviour consistently covarying with baseline GCs. Furthermore, at low altitudes, changes in covariations between RMR and personality are associated with adjustment of energy management models. Evidently, animal physiological states that determine or covary with personality can adapt according to the seasonal thermal environment and the thermal evolutionary background of populations. Our findings highlight the importance of a multi-system physiological approach to understand the evolution of animal personality.
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Affiliation(s)
- Song Tan
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu610041, People’s Republic of China
- College of Life Sciences, Sichuan University, Chengdu610064, People’s Republic of China
- University of the Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing100049, People’s Republic of China
| | - Juan Li
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu610041, People’s Republic of China
| | - Jingfeng Chen
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu610041, People’s Republic of China
- University of the Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing100049, People’s Republic of China
| | - Jinzhong Fu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu610041, People’s Republic of China
- Department of Integrative Biology, University of Guelph, Guelph, OntarioN1G 2W1, Canada
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4
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Yousaf MN, Røn Ø, Keitel-Gröner F, McGurk C, Obach A. Heart rate as an indicator of stress during the critical swimming speed test of farmed Atlantic salmon (Salmo salar L.). JOURNAL OF FISH BIOLOGY 2024; 104:633-646. [PMID: 37903720 DOI: 10.1111/jfb.15602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/25/2023] [Accepted: 10/27/2023] [Indexed: 11/01/2023]
Abstract
A swim tunnel is to fish as a treadmill is to humans, and is a device used for indirect measuring of the metabolic rate. This study aims to explore the fish stress (if any) during the critical swimming test routines (fish handling, confinement, and swimming) using heart rate (fH , heartbeat per minute) bio-loggers in farmed Atlantic salmon (Salmo salar L.). In addition, the recovery dynamics of exercised fish using fH were explored for 48 h post swim tests. Continuous fH data were acquired following the surgical implantation and throughout the trials, such as during fish handling, swim tests (critical swimming speed, Ucrit ), and 48 h post swim tests. After 3 weeks of surgical recovery, fH stabilized at 46.20 ± 1.26 beats min-1 , equalizing a ~38% reduction in fH recorded post-surgical tachycardia (74.13 ± 1.44 beats min-1 ). Interestingly, fH was elevated by ~200% compared to baseline levels not only due to the Ucrit (92.04 ± 0.23 beats min-1 ) but also due to fish handling and confinement in the swim tunnel, which was 66% above the baseline levels (77.48 ± 0.34 beats min-1 ), suggesting fish stress. Moreover, significantly higher plasma cortisol levels (199.56 ± 77.17 ng mL-1 ) corresponding to a ~300% increase compared to baseline levels (47.92 ± 27.70 ng mL-1 ) were identified after Ucrit , predicting post-swim test stress (physiological exhaustion). These findings reinforce the importance of fish acclimation in the swim tunnel prior to the swimming tests. However, fH dropped over the course of the 48-h post-swim test, but remained comparatively higher than the basal levels, suggesting fish should be given at least 48 h to recover from handling stress for better fish welfare. This study further explored the influence of fish tagging on Ucrit , which resulted in reduced swimming capabilities of tagged fish (1.95 ± 0.37 body lengths s-1 ) compared to untagged fish (2.54 ± 0.42 body length s-1 ), although this was not significant (p = 0.06), and therefore future tagging studies are warranted.
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Affiliation(s)
| | - Øyvind Røn
- Skretting Aquaculture Innovation (Skretting AI), Stavanger, Norway
| | | | - Charles McGurk
- Skretting Aquaculture Innovation (Skretting AI), Stavanger, Norway
| | - Alex Obach
- Skretting Aquaculture Innovation (Skretting AI), Stavanger, Norway
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5
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Meehan ZM, Hubbard JA, Moore CC, Mlawer F. Susceptibility to peer influence in adolescents: Associations between psychophysiology and behavior. Dev Psychopathol 2024; 36:69-81. [PMID: 36148857 DOI: 10.1017/s0954579422000967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The current study investigated in-the-moment links between adolescents' autonomic nervous system activity and susceptibility to three types of peer influence (indirect, direct, continuing) on two types of behavior (antisocial, prosocial). The sample included 144 racially ethnically diverse adolescents (46% male, 53% female, 1% other; M age = 16.02 years). We assessed susceptibility to peer influence behaviorally using the Public Goods Game (PGG) while measuring adolescents' mean heart rate (MHR) and pre-ejection period (PEP). Three key findings emerged from bivariate dual latent change score modeling: (1) adolescents whose MHR increased more as they transitioned from playing the PGG alone (pre-influence) to playing while simply observed by peers (indirect influence) displayed more prosocial behavior; (2) adolescents whose PEP activity increased more (greater PEP activity = shorter PEP latency) as they transitioned from indirect influence to being encouraged by peers to engage in antisocial behavior (direct influence) engaged in more antisocial behavior; and (3) adolescents whose PEP activity decreased less as they transitioned from direct influence on prosocial behavior to playing the PGG alone again (continuing influence) displayed more continuing prosocial behavior (marginal effect). The discussion focuses on the role of psychophysiology in understanding adolescents' susceptibility to peer influence.
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Affiliation(s)
- Zachary M Meehan
- Department of Psychological and Brain Sciences, University of Delaware, Delaware, 105 The Green, 108 Wolf Hall, Newark, DE19716, USA
| | - Julie A Hubbard
- Department of Psychological and Brain Sciences, University of Delaware, Delaware, 105 The Green, 108 Wolf Hall, Newark, DE19716, USA
| | - Christina C Moore
- Department of Psychological and Brain Sciences, University of Delaware, Delaware, 105 The Green, 108 Wolf Hall, Newark, DE19716, USA
| | - Fanny Mlawer
- Department of Psychological and Brain Sciences, University of Delaware, Delaware, 105 The Green, 108 Wolf Hall, Newark, DE19716, USA
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6
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Birch G, Meniri M, Cant MA, Blount JD. Defence against the intergenerational cost of reproduction in males: oxidative shielding of the germline. Biol Rev Camb Philos Soc 2024; 99:70-84. [PMID: 37698166 DOI: 10.1111/brv.13012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 08/09/2023] [Accepted: 08/11/2023] [Indexed: 09/13/2023]
Abstract
Reproduction is expected to carry an oxidative cost, yet in many species breeders appear to sustain lower levels of oxidative damage compared to non-breeders. This paradox may be explained by considering the intergenerational costs of reproduction. Specifically, a reduction in oxidative damage upon transitioning to a reproductive state may represent a pre-emptive shielding strategy to protect the next generation from intergenerational oxidative damage (IOD) - known as the oxidative shielding hypothesis. Males may be particularly likely to transmit IOD, because sperm are highly susceptible to oxidative damage. Yet, the possibility of male-mediated IOD remains largely uninvestigated. Here, we present a conceptual and methodological framework to assess intergenerational costs of reproduction and oxidative shielding of the germline in males. We discuss variance in reproductive costs and expected payoffs of oxidative shielding according to species' life histories, and the expected impact on offspring fitness. Oxidative shielding presents an opportunity to incorporate intergenerational effects into the advancing field of life-history evolution.
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Affiliation(s)
- Graham Birch
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
| | - Magali Meniri
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
| | - Michael A Cant
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
| | - Jonathan D Blount
- Centre for Ecology & Conservation, Faculty of Environment, Science & Economy, University of Exeter, Penryn Campus, Cornwall, TR10 9FE, UK
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7
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Sadhir S, Pontzer H. Impact of energy availability and physical activity on variation in fertility across human populations. J Physiol Anthropol 2023; 42:1. [PMID: 36829218 PMCID: PMC9951524 DOI: 10.1186/s40101-023-00318-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 02/08/2023] [Indexed: 02/26/2023] Open
Abstract
Human reproduction is energetically costly, even more so than other primates. In this review, we consider how the energy cost of physical activity impacts reproductive tasks. Daily energy expenditure appears to be constrained, leading to trade-offs between activity and reproduction expenditures in physically active populations. High workloads can lead to suppression of basal metabolic rate and low gestational weight gain during pregnancy and longer interbirth intervals. These responses lead to variation in fertility, including age at first reproduction and interbirth interval. The influence of energetics is evident even in industrialized populations, where cultural and economic factors predominate. With the decoupling of skills acquisition from food procurement, extrasomatic resources and investment in individual offspring becomes very costly. The result is greater investment in fewer offspring. We present a summary of age at first reproduction and interbirth interval trends across a diverse, global sample representing 44 countries and two natural fertility populations. While economic factors impact fertility, women in energy-rich, industrialized populations are capable of greater reproductive output than women in energy-stressed populations. Thus, energetic factors can be disentangled from cultural and economic impacts on fertility. Future research should focus on objective measurements of energy intake, energy expenditure, and physical activity in a broader sample of populations to elucidate the role of energetics in shaping reproductive outcomes and health.
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Affiliation(s)
- Srishti Sadhir
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA.
| | - Herman Pontzer
- grid.26009.3d0000 0004 1936 7961Department of Evolutionary Anthropology, Duke University, Durham, NC USA ,grid.26009.3d0000 0004 1936 7961Duke Global Health Institute, Duke University, Durham, NC USA
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8
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Pronounced differences in heart rate and metabolism distinguish daily torpor and short-term hibernation in two bat species. Sci Rep 2022; 12:21721. [PMID: 36522368 PMCID: PMC9755216 DOI: 10.1038/s41598-022-25590-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 12/01/2022] [Indexed: 12/23/2022] Open
Abstract
Torpor, and its differential expression, is essential to the survival of many mammals and birds. Physiological characteristics of torpor appear to vary between those species that express strict daily heterothermy and those capable of multiday hibernation, but comparisons are complicated by the temperature-dependence of variables. Previous reviews have compared these different torpor strategies by measuring the depth and duration of torpor in multiple species. However, direct comparison of multiple physiological parameters under similar thermal conditions are lacking. Here, we quantified three physiological variables; body temperature, metabolic rate (MR) and heart rate (HR) of two small heterothermic bats (daily heterotherm Syconycteris australis, and hibernator Nyctophilus gouldi) under comparable thermal conditions and torpor bout durations. When normothermic and resting both MR and HR were similar for the two species. However, during torpor the minimum HR was more than fivefold higher, and minimum MR was 6.5-fold higher for the daily heterotherm than for the hibernator at the same subcutaneous Tb (16 ± 0.5 °C). The data show that the degree of heterothermy defined using Tb is not necessarily a precise proxy for physiological capacity during torpor in these bats and is unlikely to reveal accurate energy budgets. Our study provides evidence supporting a distinction between daily torpor in a daily heterotherm and short term torpor in a hibernator, at least within the Chiroptera with regard to these physiological variables. This exists even when individuals display the same degree of Tb reduction, which has clear implications for the modelling of their energy expenditure.
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9
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Wascher CAF, Arnold W, Kotrschal K. Effects of severe anthropogenic disturbance on the heart rate and body temperature in free-living greylag geese ( Anser anser). CONSERVATION PHYSIOLOGY 2022; 10:coac050. [PMID: 36033970 PMCID: PMC9406602 DOI: 10.1093/conphys/coac050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 06/12/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Anthropogenic disturbances are a major concern for the welfare and conservation of wildlife. We recorded heart rate and body temperature of 20 free-living greylag geese in response to a major regularly re-occurring anthropogenic disturbance-New Year's Eve fireworks. Heart rate and body temperature were significantly higher in the first and second hour of the new year, compared with the same hour on the 31st of December, the average during December and the average during January. Heart rate and body temperature was not significantly affected by sex or age. From 0200 to 0300 onwards, 1st of January heart rates did not significantly differ from the other periods; however, body temperatures were significantly increased until 0300-0400. From 0400 to 0500, heart rate was not affected by any of the investigated factors, whereas body temperature was significantly increased on the 1st of January compared with the 31st of December and the December average but not compared with the January average. To conclude, our results show that New Year's Eve fireworks cause a substantial physiological response, indicative of a stress response in greylag geese, which is costly in terms of energy expenditure.
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Affiliation(s)
- Claudia A F Wascher
- Corresponding author: School of Life Sciences, Anglia Ruskin University, East Road, Cambridge, CB1 1PT, UK. Tel: +4369912381419.
| | - Walter Arnold
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, A-1160 Vienna, Austria
| | - Kurt Kotrschal
- Core Facility Konrad Lorenz Forschungsstelle for Behaviour and Cognition, University of Vienna, 4645 Grünau im Almtal, Austria
- Department of Behavioural Biology, University of Vienna, 1090 Vienna, Austria
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10
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Pontzer H, McGrosky A. Balancing growth, reproduction, maintenance, and activity in evolved energy economies. Curr Biol 2022; 32:R709-R719. [PMID: 35728556 DOI: 10.1016/j.cub.2022.05.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Economic models predominate in life history research, which investigates the allocation of an organism's resources to growth, reproduction, and maintenance. These approaches typically employ a heuristic Y model of resource allocation, which predicts trade-offs among tasks within a fixed budget. The common currency among tasks is not always specified, but most models imply that metabolic energy, either from food or body stores, is the critical resource. Here, we review the evidence for metabolic energy as the common currency of growth, reproduction, and maintenance, focusing on studies in humans and other vertebrates. We then discuss the flow of energy to competing physiological tasks (physical activity, maintenance, and reproduction or growth) and its effect on life history traits. We propose a Ψ model of energy flow to these tasks, which provides an integrative framework for examining the influence of environmental factors and the expansion and contraction of energy budgets in the evolution of life history strategies.
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Affiliation(s)
- Herman Pontzer
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA; Duke Global Health Institute, Duke University, Durham, NC, USA.
| | - Amanda McGrosky
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
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11
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Baškiera S, Gvoždík L. Individual Variation in Thermal Reaction Norms Reveals Metabolic-Behavioral Relationships in an Ectotherm. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.850941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ectothermic organisms respond to rapid environmental change through a combination of behavioral and physiological adjustments. As behavioral and physiological traits are often functionally linked, an effective ectotherm response to environmental perturbation will depend on the direction and magnitude of their association. The role of various modifiers in behavioral-physiological relationships remains largely unexplored. We applied a repeated-measures approach to examine the influence of body temperature and individual variation on the link between resting metabolic rate (RMR) and exploratory locomotor activity (ELA) in juvenile Alpine newts, Ichthyosaura alpestris. We analyzed trait relationships at two body temperatures separately and as parameters, intercepts and slopes, of thermal reaction norms for both traits. Body temperature affected the level of detectable among-individual variation in two different directions. Among-individual variation in ELA was detected at 12°C, while RMR was repeatable at 22°C. We found no support for a link between RMR and ELA at either temperature. While analysis of intercepts revealed among-individual variation in both traits, among-individual variation in slopes was detected in RMR only. Intercepts were positively associated at the individual, but not the whole-phenotypic, level. For ELA, the target of selection should be individual trait values across temperatures, rather than their thermal sensitivities. The positive association between intercepts of thermal reaction norms for ELA and RMR suggests that phenotypic selection acts on both traits in a correlated fashion. Measurements at one body temperature and within-individual variation hide the metabolic-behavioral relations. We conclude that correlative studies on flexible behavioral and physiological traits in ectotherms require repeated measurement at two or more body temperatures in order to avoid misleading results. This approach is needed to fully understand ectotherm responses to environmental change and its impact on their population dynamics.
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12
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Parlin AF, Schaeffer PJ. Cardiovascular contributions and energetic costs of thermoregulation in ectothermic vertebrates. J Exp Biol 2022; 225:274253. [PMID: 35119074 DOI: 10.1242/jeb.243095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/27/2021] [Indexed: 11/20/2022]
Abstract
Ectothermic vertebrates use a suite of physiological and behavioral mechanisms to thermoregulate, which result in various thermoregulatory strategies from thermoconformity to thermoregulation. Here, we present a novel synthesis of theoretical and empirical methods to determine cardiovascular contributions to heat transfer in free-living ectothermic vertebrates. We start by identifying the fundamental components of heat transfer and the cardiovascular mechanisms for physiological modulation of heat exchange, and then integrate these components into a single, integrative framework: the cardiovascular heat exchange framework (CHEF). We demonstrate that this framework can identify details of the thermoregulatory strategy in two turtle species, most notably the preponderance of instances where turtles use physiological mechanisms to avoid overheating, suggesting vulnerability to climate change. As modulated physiological contributions to heat flow incur a greater energy demand than relying on unmodulated passive heat transfer, we then asked whether we could characterize the energetic costs of thermoregulation. We measured field metabolic rate (FMR) in free-living turtles and used the CHEF to determine FMR while actively or passively thermoregulating. Comparing an individual's actual FMR to the rate calculated assuming absence of thermoregulation revealed that painted turtles, a partial thermoregulator, elevate their daily energy expenditure (DEE) by about 25%, while box turtles, a thermoconformer, have a DEE that is nearly unchanged as a result of thermoregulation. This integrative framework builds a new paradigm that provides a mechanism to explain correlations between energy demand and thermoregulatory strategy, quantifies the energetic costs of thermoregulation, and identifies the role of cardiovascular contributions to thermoregulation in free-living animals.
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Affiliation(s)
- Adam F Parlin
- Department of Biology, Miami University, Oxford, OH 45056, USA
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13
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Abdeen A, Agnani P, Careau V. The active mouse rests within: Energy management among and within individuals. Funct Ecol 2022. [DOI: 10.1111/1365-2435.13979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Aly Abdeen
- Department of Biology University of Ottawa Ottawa ON Canada
| | - Paul Agnani
- Department of Biology University of Ottawa Ottawa ON Canada
| | - Vincent Careau
- Department of Biology University of Ottawa Ottawa ON Canada
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14
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Bennison A, Giménez J, Quinn JL, Green JA, Jessopp M. A bioenergetics approach to understanding sex differences in the foraging behaviour of a sexually monomorphic species. ROYAL SOCIETY OPEN SCIENCE 2022; 9:210520. [PMID: 35116139 PMCID: PMC8790366 DOI: 10.1098/rsos.210520] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
Many animals show sexually divergent foraging behaviours reflecting different physiological constraints or energetic needs. We used a bioenergetics approach to examine sex differences in foraging behaviour of the sexually monomorphic northern gannet. We derived a relationship between dynamic body acceleration and energy expenditure to quantify the energetic cost of prey capture attempts (plunge dives). Fourteen gannets were tracked using GPS, time depth recorders (TDR) and accelerometers. All plunge dives in a foraging trip represented less than 4% of total energy expenditure, with no significant sex differences in expenditure. Despite females undertaking significantly more dives than males, this low energetic cost resulted in no sex differences in overall energy expenditure across a foraging trip. Bayesian stable isotope mixing models based on blood samples highlighted sex differences in diet; however, calorific intake from successful prey capture was estimated to be similar between sexes. Females experienced 10.28% higher energy demands, primarily due to unequal chick provisioning. Estimates show a minimum of 19% of dives have to be successful for females to meet their daily energy requirements, and 26% for males. Our analyses suggest northern gannets show sex differences in foraging behaviour primarily related to dive rate and success rather than the energetic cost of foraging or energetic content of prey.
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Affiliation(s)
- Ashley Bennison
- Centre for Marine Renewable Energy, University College Cork, Ireland
- School of Biological, Earth and Environmental Sciences, College of Science, Engineering and Food Science, University College Cork, Ireland
| | - Joan Giménez
- Centre for Marine Renewable Energy, University College Cork, Ireland
- Marine Renewable Resources Department, Institute of Marine Science (ICM-CSIC), Barcelona, Spain
| | - John L. Quinn
- School of Biological, Earth and Environmental Sciences, College of Science, Engineering and Food Science, University College Cork, Ireland
| | - Jonathan A. Green
- School of Environmental Sciences, University of Liverpool, Liverpool L69 3GP, UK
| | - Mark Jessopp
- Centre for Marine Renewable Energy, University College Cork, Ireland
- School of Biological, Earth and Environmental Sciences, College of Science, Engineering and Food Science, University College Cork, Ireland
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15
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Careau V, Halsey LG, Pontzer H, Ainslie PN, Andersen LF, Anderson LJ, Arab L, Baddou I, Bedu-Addo K, Blaak EE, Blanc S, Bonomi AG, Bouten CVC, Buchowski MS, Butte NF, Camps SGJA, Close GL, Cooper JA, Das SK, Cooper R, Dugas LR, Eaton SD, Ekelund U, Entringer S, Forrester T, Fudge BW, Goris AH, Gurven M, Hambly C, El Hamdouchi A, Hoos MB, Hu S, Joonas N, Joosen AM, Katzmarzyk P, Kempen KP, Kimura M, Kraus WE, Kushner RF, Lambert EV, Leonard WR, Lessan N, Martin CK, Medin AC, Meijer EP, Morehen JC, Morton JP, Neuhouser ML, Nicklas TA, Ojiambo RM, Pietiläinen KH, Pitsiladis YP, Plange-Rhule J, Plasqui G, Prentice RL, Rabinovich RA, Racette SB, Raichlen DA, Ravussin E, Reilly JJ, Reynolds RM, Roberts SB, Schuit AJ, Sjödin AM, Stice E, Urlacher SS, Valenti G, Van Etten LM, Van Mil EA, Wells JCK, Wilson G, Wood BM, Yanovski J, Yoshida T, Zhang X, Murphy-Alford AJ, Loechl CU, Luke AH, Rood J, Sagayama H, Schoeller DA, Wong WW, Yamada Y, Speakman JR. Energy compensation and adiposity in humans. Curr Biol 2021; 31:4659-4666.e2. [PMID: 34453886 PMCID: PMC8551017 DOI: 10.1016/j.cub.2021.08.016] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/30/2021] [Accepted: 08/04/2021] [Indexed: 12/26/2022]
Abstract
Understanding the impacts of activity on energy balance is crucial. Increasing levels of activity may bring diminishing returns in energy expenditure because of compensatory responses in non-activity energy expenditures.1-3 This suggestion has profound implications for both the evolution of metabolism and human health. It implies that a long-term increase in activity does not directly translate into an increase in total energy expenditure (TEE) because other components of TEE may decrease in response-energy compensation. We used the largest dataset compiled on adult TEE and basal energy expenditure (BEE) (n = 1,754) of people living normal lives to find that energy compensation by a typical human averages 28% due to reduced BEE; this suggests that only 72% of the extra calories we burn from additional activity translates into extra calories burned that day. Moreover, the degree of energy compensation varied considerably between people of different body compositions. This association between compensation and adiposity could be due to among-individual differences in compensation: people who compensate more may be more likely to accumulate body fat. Alternatively, the process might occur within individuals: as we get fatter, our body might compensate more strongly for the calories burned during activity, making losing fat progressively more difficult. Determining the causality of the relationship between energy compensation and adiposity will be key to improving public health strategies regarding obesity.
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Affiliation(s)
- Vincent Careau
- Department of Biology, University of Ottawa, Ottawa, ON, Canada.
| | - Lewis G Halsey
- School of Life and Health Sciences, University of Roehampton, London, UK.
| | - Herman Pontzer
- Evolutionary Anthropology, Duke University, Durham, NC, USA; Duke Global Health Institute, Duke University, Durham, NC, USA.
| | - Philip N Ainslie
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Lene F Andersen
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway
| | | | - Lenore Arab
- David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Issad Baddou
- Unité Mixte de Recherche en Nutrition et Alimentation, CNESTEN, Université Ibn Tofail URAC39, Regional Designated Center of Nutrition Associated with AFRA/IAEA, Kénitra, Morocco
| | - Kweku Bedu-Addo
- Department of Physiology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Stephane Blanc
- Nutritional Sciences, University of Georgia, Athens, GA, USA; Institut Pluridisciplinaire Hubert Curien, CNRS Université de Strasbourg, Strasbourg UMR7178, France
| | | | - Carlijn V C Bouten
- Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Maciej S Buchowski
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, Vanderbilt University, Nashville, TN, USA
| | - Nancy F Butte
- Department of Pediatrics, Baylor College of Medicine, USDA/ARS Children's Nutrition Research Center, Houston, TX, USA
| | | | - Graeme L Close
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Jamie A Cooper
- Nutritional Sciences, University of Georgia, Athens, GA, USA
| | - Sai Krupa Das
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington Street, Boston, MA 02111, USA
| | - Richard Cooper
- Department of Public Health Sciences, Parkinson School of Health Sciences and Public Health, Loyola University, Maywood, IL, USA
| | - Lara R Dugas
- Department of Public Health Sciences, Parkinson School of Health Sciences and Public Health, Loyola University, Maywood, IL, USA; Division of Epidemiology and Biostatistics, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
| | - Simon D Eaton
- Developmental Biology & Cancer Department, University College London, London, UK
| | - Ulf Ekelund
- Department of Sport Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Sonja Entringer
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Institute of Medical Psychology, Berlin, Germany; University of California, Irvine, Irvine, CA, USA
| | - Terrence Forrester
- Solutions for Developing Countries, University of the West Indies, Mona, Kingston, Jamaica
| | | | | | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Catherine Hambly
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - Asmaa El Hamdouchi
- Unité Mixte de Recherche en Nutrition et Alimentation, CNESTEN, Université Ibn Tofail URAC39, Regional Designated Center of Nutrition Associated with AFRA/IAEA, Kénitra, Morocco
| | | | - Sumei Hu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Noorjehan Joonas
- Central Health Laboratory, Ministry of Health and Wellness, Port Louis, Mauritius
| | | | | | | | - Misaka Kimura
- National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan
| | | | | | - Estelle V Lambert
- Health through Physical Activity, Lifestyle and Sport Research Centre (HPALS), FIMS International Collaborating Centre of Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - William R Leonard
- Department of Anthropology, Northwestern University, Evanston, IL, USA
| | - Nader Lessan
- Imperial College London Diabetes Centre, Abu Dhabi, UAE, Imperial College London, London, UK
| | - Corby K Martin
- Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - Anine C Medin
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway; Department of Nutrition and Public Health, Faculty of Health and Sport Sciences, University of Agder, 4630 Kristiansand, Norway
| | | | - James C Morehen
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK; The FA Group, Burton-Upon-Trent, Staffordshire, UK
| | - James P Morton
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Marian L Neuhouser
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center and School of Public Health, University of Washington, Seattle, WA, USA
| | - Theresa A Nicklas
- Department of Pediatrics, Baylor College of Medicine, USDA/ARS Children's Nutrition Research Center, Houston, TX, USA
| | - Robert M Ojiambo
- Moi University, Eldoret, Kenya; University of Global Health Equity, Kigali, Rwanda
| | - Kirsi H Pietiläinen
- Obesity Research Unit, Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki and Obesity Center, Abdominal Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | | | - Jacob Plange-Rhule
- Department of Physiology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Guy Plasqui
- Department of Nutrition and Movement Sciences, Maastricht University, Maastricht, the Netherlands
| | - Ross L Prentice
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center and School of Public Health, University of Washington, Seattle, WA, USA
| | | | - Susan B Racette
- Program in Physical Therapy and Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - David A Raichlen
- Biological Sciences and Anthropology, University of Southern California, Los Angeles, CA, USA
| | - Eric Ravussin
- Central Health Laboratory, Ministry of Health and Wellness, Port Louis, Mauritius
| | | | - Rebecca M Reynolds
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Susan B Roberts
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington Street, Boston, MA 02111, USA
| | | | - Anders M Sjödin
- Department of Nutrition, Exercise and Sports, Copenhagen University, Copenhagen, Denmark
| | | | | | | | | | - Edgar A Van Mil
- Maastricht University, Maastricht and Lifestyle Medicine Center for Children, Jeroen Bosch Hospital's-Hertogenbosch, Maastricht, the Netherlands
| | - Jonathan C K Wells
- Population, Policy and Practice Research and Teaching Department, UCL Great Ormond Street Institute of Child Health, London, UK
| | - George Wilson
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Brian M Wood
- University of California, Los Angeles, Los Angeles, USA; Max Planck Institute for Evolutionary Anthropology, Department of Human Behavior, Ecology, and Culture, Leipzig, Germany
| | - Jack Yanovski
- Growth and Obesity, Division of Intramural Research, NIH, Bethesda, MD, USA
| | - Tsukasa Yoshida
- Institute for Active Health, Kyoto University of Advanced Science, Kyoto, Japan
| | - Xueying Zhang
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Alexia J Murphy-Alford
- Nutritional and Health Related Environmental Studies Section, Division of Human Health, International Atomic Energy Agency, Vienna, Austria
| | - Cornelia U Loechl
- Nutritional and Health Related Environmental Studies Section, Division of Human Health, International Atomic Energy Agency, Vienna, Austria
| | - Amy H Luke
- Department of Public Health Sciences, Loyola University Chicago, Maywood, IL, USA.
| | - Jennifer Rood
- Pennington Biomedical Research Center, Baton Rouge, LA, USA.
| | - Hiroyuki Sagayama
- Faculty of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan.
| | - Dale A Schoeller
- Biotech Center and Nutritional Sciences, University of Wisconsin, Madison, WI, USA.
| | - William W Wong
- Department of Pediatrics, Baylor College of Medicine, USDA/ARS Children's Nutrition Research Center, Houston, TX, USA.
| | - Yosuke Yamada
- National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan; Institute for Active Health, Kyoto University of Advanced Science, Kyoto, Japan.
| | - John R Speakman
- Center for Energy Metabolism and Reproduction, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China; Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; Shenzhen Key Laboratory of Metabolic Health, CAS Center of Excellence in Animal Evolution and Genetics, Kunming, China.
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16
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Abstract
AbstractThe received wisdom on how activity affects energy expenditure is that the more activity is undertaken, the more calories will have been burned by the end of the day. Yet traditional hunter-gatherers, who lead physically hard lives, burn no more calories each day than Western populations living in labor-saving environments. Indeed, there is now a wealth of data, both for humans and other animals, demonstrating that long-term lifestyle changes involving increases in exercise or other physical activities do not result in commensurate increases in daily energy expenditure (DEE). This is because humans and other animals exhibit a degree of energy compensation at the organismal level, ameliorating some of the increases in DEE that would occur from the increased activity by decreasing the energy expended on other biological processes. And energy compensation can be sizable, reaching many hundreds of calories in humans. But the processes that are downregulated in the long-term to achieve energy compensation are far from clear, particularly in humans-we do not know how energy compensation is achieved. My review here of the literature on relevant exercise intervention studies, for both humans and other species, indicates conflict regarding the role, if any, of basal metabolic rate (BMR) or low-level activity such as fidgeting play, particularly once changes in body composition are factored out. In situations where BMR and low-level activity are not major components of energy compensation, what then drives it? I discuss how changes in mitochondrial efficiency and changes in circadian fluctuations in BMR may contribute to our understanding of energy management. Currently unexplored, these mechanisms and others may provide important insights into the mystery of how energy compensation is achieved.
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17
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Trondrud LM, Pigeon G, Albon S, Arnold W, Evans AL, Irvine RJ, Król E, Ropstad E, Stien A, Veiberg V, Speakman JR, Loe LE. Determinants of heart rate in Svalbard reindeer reveal mechanisms of seasonal energy management. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200215. [PMID: 34176322 PMCID: PMC8237166 DOI: 10.1098/rstb.2020.0215] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2021] [Indexed: 02/02/2023] Open
Abstract
Seasonal energetic challenges may constrain an animal's ability to respond to changing individual and environmental conditions. Here, we investigated variation in heart rate, a well-established proxy for metabolic rate, in Svalbard reindeer (Rangifer tarandus platyrhynchus), a species with strong seasonal changes in foraging and metabolic activity. In 19 adult females, we recorded heart rate, subcutaneous temperature and activity using biologgers. Mean heart rate more than doubled from winter to summer. Typical drivers of energy expenditure, such as reproduction and activity, explained a relatively limited amount of variation (2-6% in winter and 16-24% in summer) compared to seasonality, which explained 75% of annual variation in heart rate. The relationship between heart rate and subcutaneous temperature depended on individual state via body mass, age and reproductive status, and the results suggested that peripheral heterothermy is an important pathway of energy management in both winter and summer. While the seasonal plasticity in energetics makes Svalbard reindeer well-adapted to their highly seasonal environment, intraseasonal constraints on modulation of their heart rate may limit their ability to respond to severe environmental change. This study emphasizes the importance of encompassing individual state and seasonal context when studying energetics in free-living animals. This article is part of the theme issue 'Measuring physiology in free-living animals (Part II)'.
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Affiliation(s)
- L. Monica Trondrud
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway
| | - Gabriel Pigeon
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec, Canada, J1 K 2R1
| | - Steve Albon
- The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK
| | - Walter Arnold
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstr. 1, 1160 Vienna, Austria
| | - Alina L. Evans
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Campus Evenstad, 2418 Elverum, Norway
| | - R. Justin Irvine
- The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK
- Frankfurt Zoological Society, PO Box 100003, South Africa Street, Addis Ababa, Ethiopia
| | - Elżbieta Król
- School of Biological Sciences, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
| | - Erik Ropstad
- Faculty of Veterinary Science, Norwegian University of Life Sciences, PO Box 8146, NO-0033 Oslo, Norway
| | - Audun Stien
- Department of Arctic and Marine Biology, The Arctic University of Norway, PO Box 6050 Langnes, NO-9037 Tromsø, Norway
| | - Vebjørn Veiberg
- Norwegian Institute for Nature Research, PO Box 5685 Torgarden, NO-7485 Trondheim, Norway
| | - John R. Speakman
- School of Biological Sciences, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
- Center for Energy Metabolism and Reproduction, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
- CAS Center of Excellence in Animal Evolution and Genetics, Kunming 650223, People's Republic of China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Leif Egil Loe
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, NO-1432 Ås, Norway
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18
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Wascher CAF. Heart rate as a measure of emotional arousal in evolutionary biology. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200479. [PMID: 34176323 PMCID: PMC8237168 DOI: 10.1098/rstb.2020.0479] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2021] [Indexed: 12/18/2022] Open
Abstract
How individuals interact with their environment and respond to changes is a key area of research in evolutionary biology. A physiological parameter that provides an instant proxy for the activation of the automatic nervous system, and can be measured relatively easily, is modulation of heart rate. Over the past four decades, heart rate has been used to assess emotional arousal in non-human animals in a variety of contexts, including social behaviour, animal cognition, animal welfare and animal personality. In this review, I summarize how measuring heart rate has provided new insights into how social animals cope with challenges in their environment. I assess the advantages and limitations of different technologies used to measure heart rate in this context, including wearable heart rate belts and implantable transmitters, and provide an overview of prospective research avenues using established and new technologies, with a special focus on implications for applied research on animal welfare. This article is part of the theme issue 'Measuring physiology in free-living animals (Part II)'.
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Affiliation(s)
- Claudia A. F. Wascher
- Behavioural Ecology Research Group, School of Life Sciences, Anglia Ruskin University, East Road, Cambridge CB1 1PT, United Kingdom
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19
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Tan S, Li P, Yao Z, Liu G, Yue B, Fu J, Chen J. Metabolic cold adaptation in the Asiatic toad: intraspecific comparison along an altitudinal gradient. J Comp Physiol B 2021; 191:765-776. [PMID: 34089366 DOI: 10.1007/s00360-021-01381-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/07/2021] [Accepted: 05/19/2021] [Indexed: 11/26/2022]
Abstract
The metabolic cold adaptation (MCA) hypothesis predicts an increase in metabolic rate and thermal sensitivity of poikilotherms from cold environments as compared to those from warm environments, when measured under standardized conditions. This compensatory response is also expected to evolve in life history and behavioral traits if the reductions in these phenotypic traits at low temperature involves in a reduction in fitness. We investigated the extent to which the level of energy intake (measured as feeding rate), energy turnover (measured as standard metabolic rate, SMR) and the energy budget (energy allocation to growth and physical activity) are influenced by climatic conditions in three populations of the Asiatic toad (Bufo gargarizans) distributed across an altitudinal gradient of 1350 m in the Qionglai Mountains of Western China. We found a similar thermal reaction norm of SMR at both population and individual levels; therefore, the data did not support the MCA hypothesis. However, there was a co-gradient variation (CoGV) for mass change rate in which the high and medium altitudinal populations displayed slower mass change rates than their counterparts from low altitudes. Moreover, this CoGV pattern was accompanied by a low feeding rate and high physical activity for the high- and medium-altitude populations. Our results highlight that adjustments in energy intake and energy allocation to behaviors, but not energy allocation to metabolism of maintenance, could act as an energetic strategy to accommodate the varied growth efficiency in Asiatic toads along an altitudinal gradient.
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Affiliation(s)
- Song Tan
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
- College of Life Sciences, Sichuan University, Chengdu, 610064, China
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Ping Li
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Zhongyi Yao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
- College of Life Sciences, Sichuan University, Chengdu, 610064, China
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Gaohui Liu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
- Chinese Research Academy of Environmental Sciences, No.8, Dayangfang, Beiyuan, Beijing, 100012, China
| | - Bisong Yue
- College of Life Sciences, Sichuan University, Chengdu, 610064, China
| | - Jinzhong Fu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.
- Department of Integrative Biology, University of Guelph, Guelph, N1G 2W1, Canada.
| | - Jingfeng Chen
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, China.
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20
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Twiss SD, Brannan N, Shuert CR, Bishop AM, Pomeroy PP, Moss S. An external telemetry system for recording resting heart rate variability and heart rate in free-ranging large wild mammals. PLoS One 2021; 16:e0252013. [PMID: 34086713 PMCID: PMC8177659 DOI: 10.1371/journal.pone.0252013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 05/09/2021] [Indexed: 11/30/2022] Open
Abstract
Measures of heart rate variability (and heart rate more generally) are providing powerful insights into the physiological drivers of behaviour. Resting heart rate variability (HRV) can be used as an indicator of individual differences in temperament and reactivity to physical and psychological stress. There is increasing interest in deriving such measures from free ranging wild animals, where individuals are exposed to the natural and anthropogenic stressors of life. We describe a robust, externally mounted heart rate monitor for use in wild mammals, deployed here on wild breeding adult female grey seals (Halichoerus grypus), that delivers millisecond precise measures of inter beat intervals (IBIs), allowing computation of resting HRV parameters. Based on Firstbeat™ heart rate belts, our system allows for remote, continuous recording of IBI data from over 30 individuals simultaneously at ranges of up to 200m. We assessed the accuracy of the IBI data provided by the Firstbeat™ system using concurrent IBI data derived from in-field electrocardiogram (ECG) recordings. Bland-Altmann analyses demonstrated high correspondence between the two sets of IBI data, with a mean difference of 0.87±0.16ms. We used generalized additive mixed-effects models to examine the impact of the default Firstbeat™ software artefact correction procedure upon the generation of anomalous data (flats and stairs). Artefact correction and individual activity were major causes of flats and stairs. We used simulations and models to assess the impact of these errors on estimates of resting HRV and to inform criteria for subsampling relatively error free IBI traces. These analyses allowed us to establish stringent filtering procedures to remove traces with excessive numbers of artefacts, including flats and stairs. Even with strict criteria for removing potentially erroneous data, the abundance of data yielded by the Firstbeat™ system provides the potential to extract robust estimates of resting HRV. We discuss the advantages and limitations of our system for applications beyond the study system described here.
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Affiliation(s)
- Sean D. Twiss
- Department of Biosciences, Durham University, Durham, United Kingdom
- * E-mail:
| | - Naomi Brannan
- Department of Biosciences, Durham University, Durham, United Kingdom
| | | | - Amanda M. Bishop
- Department of Biosciences, Durham University, Durham, United Kingdom
| | - Patrick. P. Pomeroy
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews, United Kingdom
| | - Simon Moss
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews, United Kingdom
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21
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Abstract
Temperature is an important environmental factor governing the ability of organisms to grow, survive and reproduce. Thermal performance curves (TPCs), with some caveats, are useful for charting the relationship between body temperature and some measure of performance in ectotherms, and provide a standardized set of characteristics for interspecific comparisons. Endotherms, however, have a more complicated relationship with environmental temperature, as endothermy leads to a decoupling of body temperature from external temperature through use of metabolic heat production, large changes in insulation and variable rates of evaporative heat loss. This has impeded our ability to model endothermic performance in relation to environmental temperature as well as to readily compare performance between species. In this Commentary, we compare the strengths and weaknesses of potential TPC analogues (including other useful proxies for linking performance to temperature) in endotherms and suggest several ways forward in the comparative ecophysiology of endotherms. Our goal is to provide a common language with which ecologists and physiologists can evaluate the effects of temperature on performance. Key directions for improving our understanding of endotherm thermoregulatory physiology include a comparative approach to the study of the level and precision of body temperature, measuring performance directly over a range of body temperatures and building comprehensive mechanistic models of endotherm responses to environmental temperatures. We believe the answer to the question posed in the title could be 'yes', but only if 'performance' is well defined and understood in relation to body temperature variation, and the costs and benefits of endothermy are specifically modelled.
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Affiliation(s)
| | - Katie E Marshall
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
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22
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Hicks O, Kato A, Angelier F, Wisniewska DM, Hambly C, Speakman JR, Marciau C, Ropert-Coudert Y. Acceleration predicts energy expenditure in a fat, flightless, diving bird. Sci Rep 2020; 10:21493. [PMID: 33299039 PMCID: PMC7726140 DOI: 10.1038/s41598-020-78025-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 11/18/2020] [Indexed: 12/15/2022] Open
Abstract
Energy drives behaviour and life history decisions, yet it can be hard to measure at fine scales in free-moving animals. Accelerometry has proven a powerful tool to estimate energy expenditure, but requires calibration in the wild. This can be difficult in some environments, or for particular behaviours, and validations have produced equivocal results in some species, particularly air-breathing divers. It is, therefore, important to calibrate accelerometry across different behaviours to understand the most parsimonious way to estimate energy expenditure in free-living conditions. Here, we combine data from miniaturised acceleration loggers on 58 free-living Adélie penguins with doubly labelled water (DLW) measurements of their energy expenditure over several days. Across different behaviours, both in water and on land, dynamic body acceleration was a good predictor of independently measured DLW-derived energy expenditure (R2 = 0.72). The most parsimonious model suggested different calibration coefficients are required to predict behaviours on land versus foraging behaviour in water (R2 = 0.75). Our results show that accelerometry can be used to reliably estimate energy expenditure in penguins, and we provide calibration equations for estimating metabolic rate across several behaviours in the wild.
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Affiliation(s)
- Olivia Hicks
- Centre D'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR 7372, Villiers-en-Bois, France.
| | - Akiko Kato
- Centre D'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR 7372, Villiers-en-Bois, France
| | - Frederic Angelier
- Centre D'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR 7372, Villiers-en-Bois, France
| | - Danuta M Wisniewska
- Centre D'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR 7372, Villiers-en-Bois, France
| | - Catherine Hambly
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - John R Speakman
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Coline Marciau
- Centre D'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR 7372, Villiers-en-Bois, France
| | - Yan Ropert-Coudert
- Centre D'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR 7372, Villiers-en-Bois, France
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23
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Green JA. Assessing the functional significance of metabolism and activity in niche diversification. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Jonathan A. Green
- School of Environmental Sciences University of Liverpool Liverpool UK
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24
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Kozłowski J, Konarzewski M, Czarnoleski M. Coevolution of body size and metabolic rate in vertebrates: a life-history perspective. Biol Rev Camb Philos Soc 2020; 95:1393-1417. [PMID: 32524739 PMCID: PMC7540708 DOI: 10.1111/brv.12615] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 05/05/2020] [Accepted: 05/07/2020] [Indexed: 12/30/2022]
Abstract
Despite many decades of research, the allometric scaling of metabolic rates (MRs) remains poorly understood. Here, we argue that scaling exponents of these allometries do not themselves mirror one universal law of nature but instead statistically approximate the non-linearity of the relationship between MR and body mass. This 'statistical' view must be replaced with the life-history perspective that 'allows' organisms to evolve myriad different life strategies with distinct physiological features. We posit that the hypoallometric allometry of MRs (mass scaling with an exponent smaller than 1) is an indirect outcome of the selective pressure of ecological mortality on allocation 'decisions' that divide resources among growth, reproduction, and the basic metabolic costs of repair and maintenance reflected in the standard or basal metabolic rate (SMR or BMR), which are customarily subjected to allometric analyses. Those 'decisions' form a wealth of life-history variation that can be defined based on the axis dictated by ecological mortality and the axis governed by the efficiency of energy use. We link this variation as well as hypoallometric scaling to the mechanistic determinants of MR, such as metabolically inert component proportions, internal organ relative size and activity, cell size and cell membrane composition, and muscle contributions to dramatic metabolic shifts between the resting and active states. The multitude of mechanisms determining MR leads us to conclude that the quest for a single-cause explanation of the mass scaling of MRs is futile. We argue that an explanation based on the theory of life-history evolution is the best way forward.
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Affiliation(s)
- Jan Kozłowski
- Institute of Environmental SciencesJagiellonian UniversityGronostajowa7, 30‐387KrakówPoland
| | - Marek Konarzewski
- Institute of BiologyUniversity of BiałystokCiołkowskiego 1J, 15‐245, BiałystokPoland
| | - Marcin Czarnoleski
- Institute of Environmental SciencesJagiellonian UniversityGronostajowa7, 30‐387KrakówPoland
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25
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Baškiera S, Gvoždík L. Thermal independence of energy management in a tailed amphibian. JOURNAL OF VERTEBRATE BIOLOGY 2020. [DOI: 10.25225/jvb.20057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Senka Baškiera
- Department of Botany and Zoology, Masaryk University, Brno, Czech Republic; e-mail:
| | - Lumír Gvoždík
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic; e-mail:
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26
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Flack A, Schaeffer PJ, Taylor JRE, Müller I, Wikelski M, Fiedler W. Daily energy expenditure in white storks is lower after fledging than in the nest. J Exp Biol 2020; 223:jeb219337. [PMID: 31900347 DOI: 10.1242/jeb.219337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 12/17/2019] [Indexed: 01/26/2023]
Abstract
Many juvenile birds turn into long-distance migrants within weeks of fledging. This transition involves upheavals in their energy management as major changes in growth and activity occur. Understanding such ontogenetic transitions in energy allocation has been difficult because collecting continuous data on energy costs in wild developing birds was previously largely impossible. Here, we continuously measured heart rate and fine-scale movements of 20 free-living juvenile white storks (Ciconia ciconia) using on-board bio-loggers to explore individual and environmental factors relating to daily mean heart rate. In addition, we explored which specific energy management strategy storks use during these crucial early life stages. We found that daily mean heart rate increased with overall movement activity, and increasing body temperature, but that it decreased with age. Further, we found that during the nestling period, when growth costs are high, activity costs are low, and post-fledging that activity costs are increased while maintenance costs are low, indicating a constraint on overall energy use in both phases. Our observations are consistent with the hypothesis that individuals invested more energy per unit time while still in the nest than after fledging despite the high costs of flight.
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Affiliation(s)
- Andrea Flack
- Department of Migration, Max Planck Institute of Animal Behavior, 78315 Radolfzell, Germany
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, D-78468 Konstanz, Germany
| | - Paul J Schaeffer
- Department of Biology, Miami University, 212 Pearson Hall, 700 E. High Street, Oxford, OH 45056, USA
| | - Jan R E Taylor
- Faculty of Biology, University of Białystok, ul. Ciołkowskiego 1J, 15-245 Białystok, Poland
| | - Inge Müller
- Department of Migration, Max Planck Institute of Animal Behavior, 78315 Radolfzell, Germany
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, D-78468 Konstanz, Germany
| | - Martin Wikelski
- Department of Migration, Max Planck Institute of Animal Behavior, 78315 Radolfzell, Germany
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, D-78468 Konstanz, Germany
| | - Wolfgang Fiedler
- Department of Migration, Max Planck Institute of Animal Behavior, 78315 Radolfzell, Germany
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, D-78468 Konstanz, Germany
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27
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Jahn M, Seebacher F. Cost of transport is a repeatable trait but is not determined by mitochondrial efficiency in zebrafish ( Danio rerio). ACTA ACUST UNITED AC 2019; 222:jeb.201400. [PMID: 30962281 DOI: 10.1242/jeb.201400] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/02/2019] [Indexed: 01/05/2023]
Abstract
The energy used to move a given distance (cost of transport; CoT) varies significantly between individuals of the same species. A lower CoT allows animals to allocate more of their energy budget to growth and reproduction. A higher CoT may cause animals to adjust their movement across different environmental gradients to reduce energy allocated to movement. The aim of this project was to determine whether CoT is a repeatable trait within individuals, and to determine its physiological causes and ecological consequences. We found that CoT is a repeatable trait in zebrafish (Danio rerio). We rejected the hypothesis that mitochondrial efficiency (P/O ratios) predicted CoT. We also rejected the hypothesis that CoT is modulated by temperature acclimation, exercise training or their interaction, although CoT increased with increasing acute test temperature. There was a weak but significant negative correlation between CoT and dispersal, measured as the number of exploration decisions made by fish, and the distance travelled against the current in an artificial stream. However, CoT was not correlated with the voluntary speed of fish moving against the current. The implication of these results is that CoT reflects a fixed physiological phenotype of an individual, which is not plastic in response to persistent environmental changes. Consequently, individuals may have fundamentally different energy budgets as they move across environments, and may adjust movement patterns as a result of allocation trade-offs. It was surprising that mitochondrial efficiency did not explain differences in CoT, and our working hypothesis is that the energetics of muscle contraction and relaxation may determine CoT. The increase in CoT with increasing acute environmental temperature means that warming environments will increase the proportion of the energy budget allocated to locomotion unless individuals adjust their movement patterns.
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Affiliation(s)
- Miki Jahn
- School of Life and Environmental Sciences A08, University of Sydney, Sydney, NSW 2006, Australia
| | - Frank Seebacher
- School of Life and Environmental Sciences A08, University of Sydney, Sydney, NSW 2006, Australia
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28
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Halsey LG, Perna A. Regression dilution in energy management patterns. ACTA ACUST UNITED AC 2019; 222:jeb.197434. [PMID: 30833460 DOI: 10.1242/jeb.197434] [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: 01/10/2019] [Accepted: 02/26/2019] [Indexed: 02/04/2023]
Abstract
Analysis of some experimental biology data involves linear regression and interpretation of the resulting slope value. Usually, the x-axis measurements include noise. Noise in the x-variable can create regression dilution, and many biologists are not aware of the implications: regression dilution results in an underestimation of the true slope value. This is particularly problematic when the slope value is diagnostic. For example, energy management strategies of animals can be determined from the regression slope estimate of mean energy expenditure against resting energy expenditure. Typically, energy expenditure is represented by a proxy such as heart rate, which adds substantive measurement error. With simulations and analysis of empirical data, we explore the possible effect of regression dilution on interpretations of energy management strategies. We conclude that unless the coefficient of determination r 2 is very high, there is a good possibility that regression dilution will affect qualitative interpretation. We recommend some ways to contend with regression dilution, including the application of alternative available regression approaches under certain circumstances.
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Affiliation(s)
- Lewis G Halsey
- Department of Life Sciences, University of Roehampton, London SW15 4JD, UK
| | - Andrea Perna
- Department of Life Sciences, University of Roehampton, London SW15 4JD, UK
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