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Debruyn G, Geltmeyer J, Schoolaert E, Nicolaï MPJ, Xie W, Wynant M, Shawkey MD, De Clerck K, D'Alba L. Hydric Environment and Chemical Composition Shape Non-avian Reptile Eggshell Absorption. Integr Comp Biol 2024; 64:107-119. [PMID: 38755009 DOI: 10.1093/icb/icae040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 04/19/2024] [Accepted: 05/06/2024] [Indexed: 05/18/2024] Open
Abstract
The amniotic egg fulfils a critical role in reproduction by serving as an interface between the external environment and the embryo. Because non-avian reptiles are rarely incubated, they must be heated by, and absorb water from, the oviposition site for the developing embryo. The mechanisms by which they absorb sufficient, but not excess, water and how these mechanisms vary with local habitat is largely unknown, despite its significance to their evolution. Here, we first performed histology, Fourier-transform infrared spectroscopy and dynamic vapor sorption experiments to elucidate the mechanisms of eggshell absorption for 56 reptile species. Then, we used phylogenetic comparative analysis to test the hypothesis that the absorptive capacity of reptile eggshells increases with aridity of the environment. We found that water absorption increases in the presence of a superficial mucopolysaccharide layer and decreases with increased calcium content. We found that eggs from arid environments have highly absorbent eggshells, but only in species with weakly calcified shells. Our results suggest that reptile eggshells have over evolutionary time tuned absorptive capacity to environmental moisture level. Since these eggs often must sustain conflicting constraints, they may serve as inspirations for new biomimetic materials, such as water filtering membranes or humidity sensors.
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Affiliation(s)
- Gerben Debruyn
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Jozefien Geltmeyer
- Center for Textile Science and Engineering, Faculty of Engineering and Architecture, University of Ghent, Tech Lane Science Park 701, B-9052 Ghent, Belgium
| | - Ella Schoolaert
- Center for Textile Science and Engineering, Faculty of Engineering and Architecture, University of Ghent, Tech Lane Science Park 701, B-9052 Ghent, Belgium
| | - Michaël P J Nicolaï
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Wanjie Xie
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Maarten Wynant
- Center for Textile Science and Engineering, Faculty of Engineering and Architecture, University of Ghent, Tech Lane Science Park 701, B-9052 Ghent, Belgium
| | - Matthew D Shawkey
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Karen De Clerck
- Center for Textile Science and Engineering, Faculty of Engineering and Architecture, University of Ghent, Tech Lane Science Park 701, B-9052 Ghent, Belgium
| | - Liliana D'Alba
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000 Ghent, Belgium
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands
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2
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Sulikowska-Drozd A, Maltz TK, Janiszewska K. Flexible embryonic shell allies large offspring size and anti-predatory protection in viviparous snails. Sci Rep 2022; 12:17881. [PMID: 36289315 PMCID: PMC9605993 DOI: 10.1038/s41598-022-22651-w] [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: 05/30/2022] [Accepted: 10/18/2022] [Indexed: 01/20/2023] Open
Abstract
The evolutionary conflicts between viviparous reproductive mode and skeleton shape may occur whenever the space available for embryo development or delivery is limited by hard inflexible structures of a parent (bones, shell, etc.). In tetrapods, offspring size is at odds with female locomotion efficiency, which results in obstetric selection. We suggest a similar relationship for viviparous gastropods, where spacious canal needed for embryo delivery may interfere with anti-predatory role of narrow and toothed shell aperture. We explored this hypothesis in the group of viviparous land snails (Clausiliidae, subfamily Phaedusinae), known for complex apertural barriers protecting the shell interior. Most of the shell structure modifications we recorded facilitate the delivery of embryos but simultaneously reduce the safeguard of a narrow shell opening. However, we also observed highly flexible embryonic shells that may withstand squeezing between apertural barriers during birth. We investigated the microstructure of these flexible embryonic shells, compared to the typical hard shells of clausiliid embryos, which are rigid and unpliable already in the genital tract of the parent. Our results suggest that the unusual flexibility, which is related to a low number of organomineral layers in the shell, evolved in two phylogenetically distant lineages of Phaedusinae. This adaptation reduces mechanical constraints for birth of the neonates but allows to maintain the protective function of the apertural barriers.
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Affiliation(s)
- A. Sulikowska-Drozd
- grid.10789.370000 0000 9730 2769Department of Invertebrate Zoology and Hydrobiology, University of Lodz, Lodz, Poland
| | - T. K. Maltz
- grid.8505.80000 0001 1010 5103Museum of Natural History, University of Wrocław, Wrocław, Poland
| | - K. Janiszewska
- grid.413454.30000 0001 1958 0162Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland
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3
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Legendre LJ, Choi S, Clarke JA. The diverse terminology of reptile eggshell microstructure and its effect on phylogenetic comparative analyses. J Anat 2022; 241:641-666. [PMID: 35758681 DOI: 10.1111/joa.13723] [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: 02/24/2022] [Revised: 05/05/2022] [Accepted: 06/16/2022] [Indexed: 11/29/2022] Open
Abstract
Reptile eggshell ensures water and gas exchange during incubation and plays a key role in reproductive success. The diversity of reptilian incubation and life history strategies has led to many clade-specific structural adaptations of their eggshell, which have been studied in extant taxa (i.e. birds, crocodilians, turtles, and lepidosaurs). Most studies on non-avian eggshells were performed over 30 years ago and categorized reptile eggshells into two main types: "hard" and "soft" - sometimes with a third intermediate category, "semi-rigid." In recent years, however, debate over the evolution of eggshell structure of major reptile clades has revealed how definitions of hard and soft eggshells influence inferred deep-time evolutionary patterns. Here, we review the diversity of extant and fossil eggshell with a focus on major reptile clades, and the criteria that have been used to define hard, soft, and semi-rigid eggshells. We show that all scoring approaches that retain these categories discretize continuous quantitative traits (e.g. eggshell thickness) and do not consider independent variation of other functionally important microstructural traits (e.g. degree of calcification, shell unit inner structure). We demonstrate the effect of three published approaches to discretizing eggshell type into hard, semi-rigid, and soft on ancestral state reconstructions using 200+ species representing all major extant and extinct reptile clades. These approaches result in different ancestral states for all major clades including Archosauria and Dinosauria, despite a difference in scoring for only 1-4% of the sample. Proposed scenarios of reptile eggshell evolution are highly conditioned by sampling, tree calibration, and lack of congruence between definitions of eggshell type. We conclude that the traditional "soft/hard/semi-rigid" classification of reptilian eggshells should be abandoned and provide guidelines for future descriptions focusing on specific functionally relevant characteristics (e.g. inner structures of shell units, pores, and membrane elements), analyses of these traits in a phylogenetic context, and sampling of previously undescribed taxa, including fossil eggs.
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Affiliation(s)
- Lucas J Legendre
- Department of Geological Sciences, University of Texas at Austin, Austin, Texas, USA
| | - Seung Choi
- Department of Earth Sciences, Montana State University, Bozeman, Montana, USA.,Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
| | - Julia A Clarke
- Department of Geological Sciences, University of Texas at Austin, Austin, Texas, USA
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4
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Kulshreshtha G, D’Alba L, Dunn IC, Rehault-Godbert S, Rodriguez-Navarro AB, Hincke MT. Properties, Genetics and Innate Immune Function of the Cuticle in Egg-Laying Species. Front Immunol 2022; 13:838525. [PMID: 35281050 PMCID: PMC8914949 DOI: 10.3389/fimmu.2022.838525] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 01/31/2022] [Indexed: 01/13/2023] Open
Abstract
Cleidoic eggs possess very efficient and orchestrated systems to protect the embryo from external microbes until hatch. The cuticle is a proteinaceous layer on the shell surface in many bird and some reptile species. An intact cuticle forms a pore plug to occlude respiratory pores and is an effective physical and chemical barrier against microbial penetration. The interior of the egg is assumed to be normally sterile, while the outer eggshell cuticle hosts microbes. The diversity of the eggshell microbiome is derived from both maternal microbiota and those of the nesting environment. The surface characteristics of the egg, outer moisture layer and the presence of antimicrobial molecules composing the cuticle dictate constituents of the microbial communities on the eggshell surface. The avian cuticle affects eggshell wettability, water vapor conductance and regulates ultraviolet reflectance in various ground-nesting species; moreover, its composition, thickness and degree of coverage are dependent on species, hen age, and physiological stressors. Studies in domestic avian species have demonstrated that changes in the cuticle affect the food safety of eggs with respect to the risk of contamination by bacterial pathogens such as Salmonella and Escherichia coli. Moreover, preventing contamination of internal egg components is crucial to optimize hatching success in bird species. In chickens there is moderate heritability (38%) of cuticle deposition with a potential for genetic improvement. However, much less is known about other bird or reptile cuticles. This review synthesizes current knowledge of eggshell cuticle and provides insight into its evolution in the clade reptilia. The origin, composition and regulation of the eggshell microbiome and the potential function of the cuticle as the first barrier of egg defense are discussed in detail. We evaluate how changes in the cuticle affect the food safety of table eggs and vertical transmission of pathogens in the production chain with respect to the risk of contamination. Thus, this review provides insight into the physiological and microbiological characteristics of eggshell cuticle in relation to its protective function (innate immunity) in egg-laying birds and reptiles.
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Affiliation(s)
- Garima Kulshreshtha
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Liliana D’Alba
- Evolutionary Ecology, Naturalis Biodiversity Center, Leiden, Netherlands
| | - Ian C. Dunn
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | | | | | - Maxwell T. Hincke
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Department of Innovation in Medical Education, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
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5
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Ke Y, Wu R, Zelenitsky DK, Brinkman D, Hu J, Zhang S, Jiang H, Han F. A large and unusually thick-shelled turtle egg with embryonic remains from the Upper Cretaceous of China. Proc Biol Sci 2021; 288:20211239. [PMID: 34403631 PMCID: PMC8370798 DOI: 10.1098/rspb.2021.1239] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/22/2021] [Indexed: 11/12/2022] Open
Abstract
Turtle eggs containing embryos are exceedingly rare in the fossil record. Here, we provide the first description and taxonomic identification, to our knowledge, of a fossilized embryonic turtle preserved in an egg, a fossil recovered from the Upper Cretaceous Xiaguan Formation of Henan Province, China. The specimen is attributed to the Nanhsiungchelyidae (Pan-Trionychia), an extinct group of large terrestrial turtles (possibly the species Yuchelys nanyangensis). The egg is rigid, spherical, and is one of the largest and thickest shelled Mesozoic turtle eggs known. Importantly, this specimen allowed identification of other nanhsiungchelyid egg clutches and comparison to those of Adocidae, as Nanhsiungchelyidae and Adocidae form the basal extinct clade Adocusia of the Pan-Trionychia (includes living soft-shelled turtles). Despite the differences in habitat adaptations, nanhsiungchelyids (terrestrial) and adocids (aquatic) shared several reproductive traits, including relatively thick eggshells, medium size clutches and relatively large eggs, which may be primitive for trionychoids (including Adocusia and Carrettochelyidae). The unusually thick calcareous eggshell of nanhsiungchelyids compared to those of all other turtles (including adocids) may be related to a nesting style adaptation to an extremely harsh environment.
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Affiliation(s)
- Yuzheng Ke
- School of Earth Science, China University of Geosciences (Wuhan), Wuhan 430074, People's Republic of China
| | - Rui Wu
- School of Earth Science, China University of Geosciences (Wuhan), Wuhan 430074, People's Republic of China
| | - Darla K. Zelenitsky
- Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Don Brinkman
- Royal Tyrrell Museum of Palaeontology, Box 7500, Drumheller, Alberta T0J 0Y0, Canada
| | - Jinfeng Hu
- School of Earth Science, China University of Geosciences (Wuhan), Wuhan 430074, People's Republic of China
| | - Shukang Zhang
- Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China
| | - Haishui Jiang
- School of Earth Science, China University of Geosciences (Wuhan), Wuhan 430074, People's Republic of China
| | - Fenglu Han
- School of Earth Science, China University of Geosciences (Wuhan), Wuhan 430074, People's Republic of China
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6
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D'Alba L, Goldenberg J, Nallapaneni A, Parkinson DY, Zhu C, Vanthournout B, Shawkey MD. Evolution of eggshell structure in relation to nesting ecology in non-avian reptiles. J Morphol 2021; 282:1066-1079. [PMID: 33713039 DOI: 10.1002/jmor.21347] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/01/2021] [Accepted: 02/21/2021] [Indexed: 12/14/2022]
Abstract
Amniotic eggs are multifunctional structures that enabled early tetrapods to colonize the land millions of years ago, and are now the reproductive mode of over 70% of all terrestrial amniotes. Eggshell morphology is at the core of animal survival, mediating the interactions between embryos and their environment, and has evolved into a massive diversity of forms and functions in modern reptiles. These functions are critical to embryonic survival and may serve as models for new antimicrobial and/or breathable membranes. However, we still lack critical data on the basic structural and functional properties of eggs, particularly of reptiles. Here, we first characterized egg shape, shell thickness, porosity, and mineralization of eggs from 91 reptile species using optical images, scanning electron microscopy, and micro computed tomography, and collected data on nesting ecology from the literature. We then used comparative analyses to test hypotheses on the selective pressures driving their evolution. We hypothesized that eggshell morphology has evolved to protect shells from physical damage and desiccation, and, in support, found a positive relationship between thickness and precipitation, and a negative relationship between porosity and temperature. Although mineralization varied extensively, it was not correlated with nesting ecology variables. Ancestral state reconstructions show thinning and increased porosity over evolutionary time in squamates, but the opposite in turtles and crocodilians. Egg shape, size, porosity and calcification were correlated, suggesting potential structural or developmental tradeoffs. This study provides new data and insights into the morphology and evolution of reptile eggs, and raises numerous questions for additional research.
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Affiliation(s)
- Liliana D'Alba
- Department of Biology, EON-Unit, Universiteit Gent, Ghent, Belgium
| | | | - Asritha Nallapaneni
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Dilworth Y Parkinson
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Chenhui Zhu
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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7
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Piazza MV, Fernández MS, Leiva PML, Piña CI, Simoncini MS. "Intracascaral space" an eggshell structure of Caiman latirostris eggs. Sci Rep 2021; 11:5579. [PMID: 33692431 PMCID: PMC7970913 DOI: 10.1038/s41598-021-85113-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 02/25/2021] [Indexed: 11/09/2022] Open
Abstract
In recent decades, eggshells of eggs from large-bodied reptiles have been studied by many researchers, to describe the eggshell, to compare them to extinct lineages that once inhabited our planet and also to understand how the egg provides the embryo specific conditions during incubation. In previous studies we described and characterized normal and pathologic Caiman latirostris eggshells; we also evaluated how the eggshell changes during incubation. In a study relating temperature variation and eggshell structures of successful eggs, we observed empty structures not previously described that we termed “intracascaral space”. The aim of this study is to describe this structure of C. latirostris eggshells. We hypothesize about the possible functions which it would perform during incubation and for development of the embryos.
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Affiliation(s)
- Mila V Piazza
- Facultad de Ciencias Agrarias, Universidad Nacional de Rosario, Campo Experimental Villarino C.C. 14, Zavalla, Santa Fe, Argentina
| | - Mariela S Fernández
- Instituto de Investigaciones en Biodiversidad y Medioambiente-Consejo Nacional de Investigaciones Científicas y Técnicas, Quintral 1250, 8300, Bariloche, Río Negro, Argentina.
| | - Pamela M L Leiva
- Centro de Investigación Científica y de Transferencia Tecnológica a la Producción-Consejo Nacional de Investigaciones Científicas y Técnicas, España 149, 3105, Diamante, Entre Ríos, Argentina.,Proyecto Yacaré, Laboratorio de Zoología Aplicada: Anexo Vertebrados (Facultad de Humanidades y Ciencias - Universidad de Nacional del Litoral / Ministerio de Aguas, Servicios Públicos y Medio Ambiente), Aristóbulo del Valle 8700, 3000, Santa Fe, Santa Fe, Argentina.,Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Tratado del Pilar 314, 3105, Diamante, Entre Ríos, Argentina
| | - Carlos I Piña
- Centro de Investigación Científica y de Transferencia Tecnológica a la Producción-Consejo Nacional de Investigaciones Científicas y Técnicas, España 149, 3105, Diamante, Entre Ríos, Argentina.,Proyecto Yacaré, Laboratorio de Zoología Aplicada: Anexo Vertebrados (Facultad de Humanidades y Ciencias - Universidad de Nacional del Litoral / Ministerio de Aguas, Servicios Públicos y Medio Ambiente), Aristóbulo del Valle 8700, 3000, Santa Fe, Santa Fe, Argentina.,Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Tratado del Pilar 314, 3105, Diamante, Entre Ríos, Argentina
| | - Melina S Simoncini
- Centro de Investigación Científica y de Transferencia Tecnológica a la Producción-Consejo Nacional de Investigaciones Científicas y Técnicas, España 149, 3105, Diamante, Entre Ríos, Argentina. .,Proyecto Yacaré, Laboratorio de Zoología Aplicada: Anexo Vertebrados (Facultad de Humanidades y Ciencias - Universidad de Nacional del Litoral / Ministerio de Aguas, Servicios Públicos y Medio Ambiente), Aristóbulo del Valle 8700, 3000, Santa Fe, Santa Fe, Argentina. .,Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Tratado del Pilar 314, 3105, Diamante, Entre Ríos, Argentina.
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8
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Norris D, Michalski F, Gibbs JP. Community based actions save Yellow-spotted river turtle ( Podocnemis unifilis) eggs and hatchlings flooded by rapid river level rises. PeerJ 2020; 8:e9921. [PMID: 32995087 PMCID: PMC7501802 DOI: 10.7717/peerj.9921] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/21/2020] [Indexed: 11/27/2022] Open
Abstract
The conservation and recovery of increasingly threatened tropical freshwater turtle populations depends on effective management plans and actions. Here we show that community-based actions saved Yellow-spotted river turtle (Podocnemis unifilis) eggs submerged by unseasonal flooding and ensured the release of hatchlings. We recovered 926 eggs and 65 premature hatchlings from 74 submerged nests at 16 flooded nesting areas along 75 km of waterways. The rescued eggs were transferred to a rearing center and incubated. Hatchlings emerged from eggs that had remained underwater for up to two days. Hatchlings were maintained in 250–500 L nursery tanks until yolk sac scars had closed. Healthy hatchlings were then immediately released around the original nesting areas. We released 599 hatchlings (60.4%) from 991 submerged eggs and hatchlings. Egg survival (61.7% (571/926)) was substantially less than hatchling survival (94.2% (599/636)) but within the expected range of values reported for this species. These findings suggest that Yellow-spotted river turtle eggs and embryos are resistant to short-term submersion, which could help explain the widespread distribution of this species across highly seasonal Amazonian rivers. Management plans should take the possible survival of submerged eggs into consideration as part of species conservation and recovery actions.
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Affiliation(s)
- Darren Norris
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil.,Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil.,School of Environmental Sciences, Federal University of Amapá, Macapá, Amapá, Brazil
| | - Fernanda Michalski
- Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil.,Postgraduate Programme in Tropical Biodiversity, Federal University of Amapá, Macapá, Amapá, Brazil.,Pro-Carnivores Institute, Atibaia, São Paulo, Brazil
| | - James P Gibbs
- Department of Environmental and Forest Biology, State University of New York, Syracuse, NY, USA
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9
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Price ER, Sotherland PR, Wallace BP, Spotila JR, Dzialowski EM. Physiological determinants of the internesting interval in sea turtles: a novel 'water-limitation' hypothesis. Biol Lett 2019; 15:20190248. [PMID: 31164061 DOI: 10.1098/rsbl.2019.0248] [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] [Indexed: 11/12/2022] Open
Abstract
The internesting interval separates successive clutches of sea turtle eggs, and its duration varies both among and within species. Here, we review the potential physiological limits to this interval, and develop the hypothesis that desalination capacity limits the internesting interval owing to the requirement for water deposition in eggs. Sea turtles deposit 1-4 kg of water per clutch in egg albumen; for most species, this represents about 2% of adult body mass. We calculate how quickly turtles can recover this water by estimating maximal salt excretion rates, metabolic water production and urinary losses. From this water balance perspective, the 'water-limitation' hypothesis is plausible for green turtles but not for leatherbacks. Some plasma biochemistry studies indicate dehydration in sea turtles during the nesting season, although this is not a universal finding and these data have rarely been collected during the internesting interval itself. There is mixed support for a trade-off between clutch size and the length of the interval. We conclude that the 'water-limitation' hypothesis is plausible for most sea turtle species, but requires direct experimentation.
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Affiliation(s)
- Edwin R Price
- 1 Department of Biological Sciences, University of North Texas , Denton, TX 76203 , USA
| | - Paul R Sotherland
- 2 Department of Biology, Kalamazoo College , Kalamazoo, MI 49007 , USA
| | - Bryan P Wallace
- 3 Ecolibrium, Inc. , Boulder, CO 80303 , USA.,4 Nicholas School of the Environment, Duke University Marine Lab , Beaufort, NC 28516 , USA
| | - James R Spotila
- 5 Department of Biodiversity, Earth and Environmental Science, Drexel University , Philadelphia, PA 19104 , USA
| | - Edward M Dzialowski
- 1 Department of Biological Sciences, University of North Texas , Denton, TX 76203 , USA
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10
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Warner DA, Du WG, Georges A. Introduction to the special issue-Developmental plasticity in reptiles: Physiological mechanisms and ecological consequences. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:153-161. [PMID: 29956505 DOI: 10.1002/jez.2199] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/30/2018] [Accepted: 06/04/2018] [Indexed: 12/13/2022]
Abstract
Scientific interest in developmental plasticity spans many disciplines, and research on reptiles has provided many insights into this field. We highlight these contributions, review the field's history, and introduce the special issue on this topic .
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Affiliation(s)
- Daniel A Warner
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Wei-Guo Du
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Arthur Georges
- Institute for Applied Ecology, University of Canberra, Canberra, Australia
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