1
|
Lara‐Reséndiz RA, Miles DB, Rosen PC, Sinervo B. Micro and macroclimatic constraints on the activity of a vulnerable tortoise: a mechanistic approach under a thermal niche view. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Rafael A. Lara‐Reséndiz
- Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas y Naturales, Centro de Zoología Aplicada and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Diversidad y Ecología Animal (IDEA) Córdoba Argentina
- Centro de Investigaciones Biológicas del Noroeste S. C. La Paz Baja California Sur México
| | - Donald B. Miles
- Department of Biological Sciences Ohio University Athens Ohio USA
| | - Philip C. Rosen
- School of Natural Resources and the Environment University of Arizona Tucson AZ USA
| | - Barry Sinervo
- Department of Ecology and Evolutionary Biology University of California California USA
| |
Collapse
|
2
|
González-Morales JC, Rivera-Rea J, Moreno-Rueda G, Bastiaans E, Díaz-Albiter H, Díaz de la Vega-Pérez AH, Bautista A, Fajardo V. To be small and dark is advantageous for gaining heat in mezquite lizards, Sceloporus grammicus (Squamata: Phrynosomatidae). Biol J Linn Soc Lond 2020. [DOI: 10.1093/biolinnean/blaa176] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Body temperature is important in determining individual performance in ectotherms such as lizards. Environmental temperature decreases with increasing altitude, but nevertheless many lizards inhabit high-altitude environments. The ‘thermal melanism hypothesis’ proposes that a dark dorsal coloration enables darker individuals to heat up faster because they absorb more solar radiation and thus being darker may be advantageous in cold habitats. The aim of the present study is to evaluate how heating rate, cooling rate and net heat gain vary with body size and dorsal skin coloration in Sceloporus grammicus lizards along an altitudinal gradient. We measured these traits multiple times in the same individuals with a radiation heat source and spectrophotometry under laboratory conditions. Our results showed that S. grammicus lizards are smaller and darker at high elevations than at low elevations. In addition, the smallest and darkest lizards showed the greatest heating rate and net heat gain. Therefore, in S. grammicus, we suggest that small body size and dark dorsal coloration provide thermoregulatory benefits in high-altitude environments. Hence, this study supports the thermal melanism hypothesis in a lizard species under varied thermal environments.
Collapse
Affiliation(s)
- Juan Carlos González-Morales
- Posgrado en Ciencias Biológicas, Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Km 1.5 Carretera Tlaxcala-Puebla S/N, AP, Tlaxcala, México
- Instituto para la Conservación de la cordillera Neovolcánica ante al Cambio Climático, Lago Atitlán, Colonia Nueva Oxtotitlán, Toluca, Estado de México, C.P., México
| | - Jimena Rivera-Rea
- Instituto para la Conservación de la cordillera Neovolcánica ante al Cambio Climático, Lago Atitlán, Colonia Nueva Oxtotitlán, Toluca, Estado de México, C.P., México
- Posgrado en Ciencias Agropecuarias y Recursos Naturales, Universidad Autónoma del Estado de México, México. Instituto Literario, Colonia Centro, Toluca, Estado de México, C.P., México
| | - Gregorio Moreno-Rueda
- Departamento de Zoología, Facultad de Ciencias, Universidad de Granada, Avda. Fuentenueva S/N, Granada, Spain
| | - Elizabeth Bastiaans
- Biology Department, State University of New York College at Oneonta, Oneonta, NY, USA
| | - Héctor Díaz-Albiter
- Centro Tlaxcala de Biología de Conducta, Universidad Autónoma de Tlaxcala, Km 1.5 Carretera Tlaxcala-Puebla S/N, Tlaxcala, México
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | | | - Amando Bautista
- Unidad Villahermosa, El Colegio de la Frontera Sur (ECOSUR), Tabasco CP, México
| | - Víctor Fajardo
- Instituto para la Conservación de la cordillera Neovolcánica ante al Cambio Climático, Lago Atitlán, Colonia Nueva Oxtotitlán, Toluca, Estado de México, C.P., México
- Universidad del Istmo, Campus Juchitán, Carretera Transísmica Juchitán - La Ventosa Km. 14, La Ventosa, C.P. Oaxaca, México
| |
Collapse
|
3
|
Sannolo M, Mangiacotti M, Sacchi R, Scali S. Keeping a cool mind: head-body temperature differences in the common wall lizard. J Zool (1987) 2014. [DOI: 10.1111/jzo.12121] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- M. Sannolo
- Museo Civico di Storia Naturale di Milano; Milano Italy
| | | | - R. Sacchi
- Dipartimento di Scienze della Terra e dell'Ambiente; Università di Pavia; Pavia Italy
| | - S. Scali
- Museo Civico di Storia Naturale di Milano; Milano Italy
| |
Collapse
|
4
|
Pincebourde S, Sanford E, Helmuth B. Survival and arm abscission are linked to regional heterothermy in an intertidal sea star. ACTA ACUST UNITED AC 2013; 216:2183-91. [PMID: 23720798 DOI: 10.1242/jeb.083881] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Body temperature is a more pertinent variable to physiological stress than ambient air temperature. Modeling and empirical studies on the impacts of climate change on ectotherms usually assume that body temperature within organisms is uniform. However, many ectotherms show significant within-body temperature heterogeneity. The relationship between regional heterothermy and the response of ectotherms to sublethal and lethal conditions remains underexplored. We quantified within-body thermal heterogeneity in an intertidal sea star (Pisaster ochraceus) during aerial exposure at low tide to examine the lethal and sublethal effects of temperatures of different body regions. In manipulative experiments, we measured the temperature of the arms and central disc, as well as survival and arm abscission under extreme aerial conditions. Survival was related strongly to central disc temperature. Arms were generally warmer than the central disc in individuals that survived aerial heating, but we found the reverse in those that died. When the central disc reached sublethal temperatures of 31-35°C, arms reached temperatures of 33-39°C, inducing arm abscission. The absolute temperature of individual arms was a poor predictor of arm abscission, but the arms lost were consistently the hottest at the within-individual scale. Therefore, the vital region of this sea star may remain below the lethal threshold under extreme conditions, possibly through water movement from the arms to the central disc and/or evaporative cooling, but at the cost of increased risk of arm abscission. Initiation of arm abscission seems to reflect a whole-organism response while death occurs as a result of stress acting directly on central disc tissues.
Collapse
Affiliation(s)
- Sylvain Pincebourde
- Institut de Recherche sur la Biologie de l'Insecte (IRBI, CNRS UMR 7261), Université François Rabelais, Faculté des Sciences et Techniques, 37200 Tours, France.
| | | | | |
Collapse
|
5
|
Sagonas K, Meiri S, Valakos ED, Pafilis P. The effect of body size on the thermoregulation of lizards on hot, dry Mediterranean islands. J Therm Biol 2013. [DOI: 10.1016/j.jtherbio.2012.11.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
6
|
Fei T, Skidmore AK, Venus V, Wang T, Schlerf M, Toxopeus B, van Overjijk S, Bian M, Liu Y. A body temperature model for lizards as estimated from the thermal environment. J Therm Biol 2012. [DOI: 10.1016/j.jtherbio.2011.10.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
7
|
Bulté G, Blouin-Demers G. Implications of extreme sexual size dimorphism for thermoregulation in a freshwater turtle. Oecologia 2009; 162:313-22. [DOI: 10.1007/s00442-009-1469-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 08/27/2009] [Indexed: 11/28/2022]
|
8
|
Are Locomotor Performances Coadapted to Preferred Basking Temperature in the Northern Map Turtle (Graptemys geographica)? J HERPETOL 2008. [DOI: 10.1670/07-1881.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
9
|
Seebacher F, Franklin CE. Redistribution of blood within the body is important for thermoregulation in an ectothermic vertebrate (Crocodylus porosus). J Comp Physiol B 2007; 177:841-8. [PMID: 17639414 DOI: 10.1007/s00360-007-0181-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Revised: 06/18/2007] [Accepted: 06/19/2007] [Indexed: 10/23/2022]
Abstract
Changes in blood flow are a principal mechanism of thermoregulation in vertebrates. Changes in heart rate will alter blood flow, although multiple demands for limited cardiac output may compromise effective thermoregulation. We tested the hypothesis that regional differences in blood flow during heating and cooling can occur independently from changes in heart rate. We measured heart rate and blood pressure concurrently with blood flow in the crocodile, Crocodylus porosus. We measured changes in blood flow by laser Doppler flowmetry, and by injecting coloured microspheres. All measurements were made under different heat loads, with and without blocking cholinergic and beta-adrenergic receptors (autonomic blockade). Heart rates were significantly faster during heating than cooling in the control animals, but not when autonomic receptors were blocked. There were no significant differences in blood flow distribution between the control and autonomic blockade treatments. In both treatments, blood flow was directed to the dorsal skin and muscle and away from the tail and duodenum during heating. When the heat source was switched off, there was a redistribution of blood from the dorsal surface to the duodenum. Blood flow to the leg skin and muscle, and to the liver did not change significantly with thermal state. Blood pressure was significantly higher during the autonomic blockade than during the control. Thermal time constants of heating and cooling were unaffected by the blockade of autonomic receptors. We concluded that animals partially compensated for a lack of differential heart rates during heating and cooling by redistributing blood within the body, and by increasing blood pressure to increase flow. Hence, measures of heart rate alone are insufficient to assess physiological thermoregulation in reptiles.
Collapse
Affiliation(s)
- Frank Seebacher
- School of Biological Sciences A08, The University of Sydney, NSW 2006, Sydney, Australia.
| | | |
Collapse
|
10
|
|
11
|
Christian KA, Tracy CR, Tracy CR. Evaluating thermoregulation in reptiles: an appropriate null model. Am Nat 2006; 168:421-30. [PMID: 16947116 DOI: 10.1086/506528] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Accepted: 05/22/2006] [Indexed: 11/03/2022]
Abstract
Established indexes of thermoregulation in ectotherms compare body temperatures of real animals with a null distribution of operative temperatures from a physical or mathematical model with the same size, shape, and color as the actual animal but without mass. These indexes, however, do not account for thermal inertia or the effects of inertia when animals move through thermally heterogeneous environments. Some recent models have incorporated body mass, to account for thermal inertia and the physiological control of warming and cooling rates seen in most reptiles, and other models have incorporated movement through the environment, but none includes all pertinent variables explaining body temperature. We present a new technique for calculating the distribution of body temperatures available to ectotherms that have thermal inertia, random movements, and different rates of warming and cooling. The approach uses a biophysical model of heat exchange in ectotherms and a model of random interaction with thermal environments over the course of a day to create a null distribution of body temperatures that can be used with conventional thermoregulation indexes. This new technique provides an unbiased method for evaluating thermoregulation in large ectotherms that store heat while moving through complex environments, but it can also generate null models for ectotherms of all sizes.
Collapse
Affiliation(s)
- Keith A Christian
- School of Science, Charles Darwin University, Darwin, Northern Territory, 0909, Australia.
| | | | | |
Collapse
|
12
|
Angilletta MJ, Bennett AF, Guderley H, Navas CA, Seebacher F, Wilson RS. Coadaptation: A Unifying Principle in Evolutionary Thermal Biology. Physiol Biochem Zool 2006; 79:282-94. [PMID: 16555188 DOI: 10.1086/499990] [Citation(s) in RCA: 199] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2005] [Indexed: 11/03/2022]
Abstract
Over the last 50 yr, thermal biology has shifted from a largely physiological science to a more integrated science of behavior, physiology, ecology, and evolution. Today, the mechanisms that underlie responses to environmental temperature are being scrutinized at levels ranging from genes to organisms. From these investigations, a theory of thermal adaptation has emerged that describes the evolution of thermoregulation, thermal sensitivity, and thermal acclimation. We review and integrate current models to form a conceptual model of coadaptation. We argue that major advances will require a quantitative theory of coadaptation that predicts which strategies should evolve in specific thermal environments. Simply combining current models, however, is insufficient to understand the responses of organisms to thermal heterogeneity; a theory of coadaptation must also consider the biotic interactions that influence the net benefits of behavioral and physiological strategies. Such a theory will be challenging to develop because each organism's perception of and response to thermal heterogeneity depends on its size, mobility, and life span. Despite the challenges facing thermal biologists, we have never been more pressed to explain the diversity of strategies that organisms use to cope with thermal heterogeneity and to predict the consequences of thermal change for the diversity of communities.
Collapse
Affiliation(s)
- Michael J Angilletta
- Department of Ecology and Organismal Biology, Indiana State University, Terre Haute, Indiana 47809, USA.
| | | | | | | | | | | |
Collapse
|
13
|
Seebacher F, Franklin CE. Physiological mechanisms of thermoregulation in reptiles: a review. J Comp Physiol B 2005; 175:533-41. [PMID: 16047177 DOI: 10.1007/s00360-005-0007-1] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Revised: 04/29/2005] [Accepted: 05/20/2005] [Indexed: 10/25/2022]
Abstract
The thermal dependence of biochemical reaction rates means that many animals regulate their body temperature so that fluctuations in body temperature are small compared to environmental temperature fluctuations. Thermoregulation is a complex process that involves sensing of the environment, and subsequent processing of the environmental information. We suggest that the physiological mechanisms that facilitate thermoregulation transcend phylogenetic boundaries. Reptiles are primarily used as model organisms for ecological and evolutionary research and, unlike in mammals, the physiological basis of many aspects in thermoregulation remains obscure. Here, we review recent research on regulation of body temperature, thermoreception, body temperature set-points, and cardiovascular control of heating and cooling in reptiles. The aim of this review is to place physiological thermoregulation of reptiles in a wider phylogenetic context. Future research on reptilian thermoregulation should focus on the pathways that connect peripheral sensing to central processing which will ultimately lead to the thermoregulatory response.
Collapse
Affiliation(s)
- Frank Seebacher
- Integrative Physiology, School of Biological Sciences A08, University of Sydney, NSW, Australia.
| | | |
Collapse
|