1
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Selescu T, Bivoleanu RA, Iodi Carstens M, Manolache A, Caragea VM, Hutanu DE, Meerupally R, Wei ET, Carstens E, Zimmermann K, Babes A. TRPM8-dependent shaking in mammals and birds. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.27.573364. [PMID: 38234797 PMCID: PMC10793462 DOI: 10.1101/2023.12.27.573364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Removing water from wet fur or feathers is important for thermoregulation in warm-blooded animals. The "wet dog shake" (WDS) behavior has been largely characterized in mammals but to a much lesser extent in birds. Although it is known that TRPM8 is the main molecular transducer of low temperature in mammals, it is not clear if wetness-induced shaking in furred and feathered animals is dependent on TRPM8. Here, we show that a novel TRPM8 agonist induces WDS in rodents and, importantly, in birds, similar to the shaking behavior evoked by water-spraying. Furthermore, the WDS onset depends on TRPM8, as we show in water-sprayed mice. Overall, our results provide multiple evidence for a TRPM8 dependence of WDS behaviors in all tested species. These suggest that a convergent evolution selected similar shaking behaviors to expel water from fur and feathers, with TRPM8 being involved in wetness sensing in both mammals and birds.
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2
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Zhou H, Niu H, Wang H, Lin T. Self-Healing Superwetting Surfaces, Their Fabrications, and Properties. Chem Rev 2023; 123:663-700. [PMID: 36537354 DOI: 10.1021/acs.chemrev.2c00486] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The research on superwetting surfaces with a self-healing function against various damages has progressed rapidly in the recent decade. They are expected to be an effective approach to increasing the durability and application robustness of superwetting materials. Various methods and material systems have been developed to prepare self-healing superwetting surfaces, some of which mimic natural superwetting surfaces. However, they still face challenges, such as being workable only for specific damages, external stimulation to trigger the healing process, and poor self-healing ability in the water, marine, or biological systems. There is a lack of fundamental understanding as well. This article comprehensively reviews self-healing superwetting surfaces, including their fabrication strategies, essential rules for materials design, and self-healing properties. Self-healing triggered by different external stimuli is summarized. The potential applications of self-healing superwetting surfaces are highlighted. This article consists of four main sections: (1) the functional surfaces with various superwetting properties, (2) natural self-healing superwetting surfaces (i.e., plants, insects, and creatures) and their healing mechanism, (3) recent research development in various self-healing superwetting surfaces, their preparation, wetting properties in the air or liquid media, and healing mechanism, and (4) the prospects including existing challenges, our views and potential solutions to the challenges, and future research directions.
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Affiliation(s)
- Hua Zhou
- College of Textiles & Clothing, State Key Laboratory for Biofibers and Eco-textiles, Collaborative Innovation Centre for Eco-textiles of Shandong Province, Qingdao University, Qingdao 266071, China
| | - Haitao Niu
- College of Textiles & Clothing, State Key Laboratory for Biofibers and Eco-textiles, Collaborative Innovation Centre for Eco-textiles of Shandong Province, Qingdao University, Qingdao 266071, China
| | - Hongxia Wang
- Institute for Frontier Materials, Deakin University, Geelong Victoria 3216, Australia.,Institute for Nanofiber Intelligent Manufacture and Applications, School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China
| | - Tong Lin
- Institute for Nanofiber Intelligent Manufacture and Applications, School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China.,State Key Laboratory of Separation Membranes and Membrane Processes, School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China
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3
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Shi K, Zhang H, Gu Y, Liang Z, Zhou H, Liu H, Liu J, Xie G. Electric Spark Deposition of Antibacterial Silver Coating on Microstructured Titanium Surfaces with a Novel Flexible Brush Electrode. ACS OMEGA 2022; 7:47108-47119. [PMID: 36570305 PMCID: PMC9773945 DOI: 10.1021/acsomega.2c06253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Infection caused by orthopedic titanium implants, which results in tissue damage, is a key factor in endosseous implant failure. Given the seriousness of implant infections and the limitations of antibiotic therapy, surface microstructures and antimicrobial silver coatings have emerged as prominent research areas and have displayed certain antimicrobial effects. Researchers are now working to combine the two to produce more effective antimicrobial surfaces. However, building robust and homogeneous coatings on complex microstructured surfaces is a tough task due to the limits of surface modification techniques. In this study, a novel flexible electrode brush (silver brush) instead of a traditional hard electrode was designed with electrical discharge machining, which has the ability to adapt to complex groove interiors. The results showed that the use of flexible electrode brush allowed silver to be deposited uniformly in titanium alloy microgrooves. On the surface of Ag-TC4, a uniformly covered deposit was visible, and it slowly released silver ions into a liquid environment. In vitro bacterial assays showed that a Ag-TC4 microstructured surface reduced bacterial adhesion and bacterial biofilm formation, and the antibacterial activity of Ag-TC4 against Staphylococcus aureus and Escherichia coli was 99.68% ± 0.002 and 99.50% ± 0.007, respectively. This research could lay the groundwork for the study of antimicrobial metal bound to microstructured surfaces and pave the way for future implant surface design.
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Affiliation(s)
- Kaihui Shi
- Guangzhou
Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious
Diseases, KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou510182, PR China
| | - Hao Zhang
- State
Key Laboratory of Precision Electronic Manufacturing Technology and
Equipment, Guangdong University of Technology, Guangzhou510006, PR China
| | - Yuyan Gu
- Guangzhou
Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious
Diseases, KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou510182, PR China
| | - Zhijie Liang
- State
Key Laboratory of Precision Electronic Manufacturing Technology and
Equipment, Guangdong University of Technology, Guangzhou510006, PR China
| | - Huanyu Zhou
- Guangzhou
Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious
Diseases, KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou510182, PR China
| | - Haojie Liu
- Guangzhou
Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious
Diseases, KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou510182, PR China
| | - Jiangwen Liu
- State
Key Laboratory of Precision Electronic Manufacturing Technology and
Equipment, Guangdong University of Technology, Guangzhou510006, PR China
| | - Guie Xie
- Guangzhou
Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious
Diseases, KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou510182, PR China
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4
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Rasmussen MH, Holler KR, Baio JE, Jaye C, Fischer DA, Gorb SN, Weidner T. Evidence that gecko setae are coated with an ordered nanometre-thin lipid film. Biol Lett 2022; 18:20220093. [PMID: 35857888 DOI: 10.1098/rsbl.2022.0093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The fascinating adhesion of gecko to virtually any material has been related to surface interactions of myriads of spatula at the tips of gecko feet. Surprisingly, the molecular details of the surface chemistry of gecko adhesion are still largely unknown. Lipids have been identified within gecko adhesive pads. However, the location of the lipids, the extent to which spatula are coated with lipids, and how the lipids are structured are still open questions. Lipids can modulate adhesion properties and surface hydrophobicity and may play an important role in adhesion. We have therefore studied the molecular structure of lipids at spatula surfaces using near-edge X-ray absorption fine structure imaging. We provide evidence that a nanometre-thin layer of lipids is present at the spatula surfaces of the tokay gecko (Gekko gecko) and that the lipids form ordered, densely packed layers. Such dense, thin lipid layers can effectively protect the spatula proteins from dehydration by forming a barrier against water evaporation. Lipids can also render surfaces hydrophobic and thereby support the gecko adhesive system by enhancement of hydrophobic-hydrophobic interactions with surfaces.
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Affiliation(s)
| | | | - Joe E Baio
- The School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, USA
| | - Cherno Jaye
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Daniel A Fischer
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Stanislav N Gorb
- Department of Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Kiel, Germany
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
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5
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Barraza B, Olate-Moya F, Montecinos G, Ortega JH, Rosenkranz A, Tamburrino A, Palza H. Superhydrophobic SLA 3D printed materials modified with nanoparticles biomimicking the hierarchical structure of a rice leaf. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2022; 23:300-321. [PMID: 35557509 PMCID: PMC9090350 DOI: 10.1080/14686996.2022.2063035] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/31/2022] [Accepted: 04/03/2022] [Indexed: 06/15/2023]
Abstract
The rice leaf, combining the surface properties of lotus leaves and shark skin, presents outstanding superhydrophobic properties motivating its biomimesis. We created a novel biomimetic rice-leaf superhydrophobic surface by a three-level hierarchical structure, using for a first time stereolithographic (SLA) 3D printed channels (100µm width) with an intrinsic roughness from the printing filaments (10µm), and coated with TiO2 nanoparticles (22 and 100nm). This structure presents a maximum advancing contact angle of 165° characterized by lower both anisotropy and hysteresis contact angles than other 3D printed surfaces, due to the presence of air pockets at the surface/water interface (Cassie-Baxter state). Dynamic water-drop tests show that the biomimetic surface presents self-cleaning, which is reduced under UV-A irradiation. The biomimetic surface further renders an increased floatability to 3D printed objects meaning a drag-reduction due to reduced water/solid contact area. Numerical simulations of a channel with a biomimetic wall confirm that the presence of air is essential to understand our results since it increases the average velocity and decreases the friction factor due to the presence of a wall-slip velocity. Our findings show that SLA 3D printing is an appropriate approach to develop biomimetic superhydrophobic surfaces for future applications in anti-fouling and drag-reduction devices.
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Affiliation(s)
- Belén Barraza
- Matemáticas, Universidad de ChileDepartamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y, Santiago, Chile
- Núcleo Milenio en Metamateriales Mecánicos Suaves e Inteligentes (Millennium Nucleus on Smart Soft Mechanical Metamaterials)
- Advanced Mining Technology Center, Universidad de Chile, Santiago, Chile
| | - Felipe Olate-Moya
- Matemáticas, Universidad de ChileDepartamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y, Santiago, Chile
- Núcleo Milenio en Metamateriales Mecánicos Suaves e Inteligentes (Millennium Nucleus on Smart Soft Mechanical Metamaterials)
| | - Gino Montecinos
- Departamento de Ingeniería Matemática, Universidad de la Frontera, Temuco, Chile
| | - Jaime H. Ortega
- Departamento de Ingeniería Matemática, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
- Centro de Modelamiento Matemático, IRL 2807 CNRS-UChile, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Andreas Rosenkranz
- Matemáticas, Universidad de ChileDepartamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y, Santiago, Chile
| | - Aldo Tamburrino
- Departamento de Ingeniería Civil, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Humberto Palza
- Matemáticas, Universidad de ChileDepartamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y, Santiago, Chile
- Núcleo Milenio en Metamateriales Mecánicos Suaves e Inteligentes (Millennium Nucleus on Smart Soft Mechanical Metamaterials)
- Advanced Mining Technology Center, Universidad de Chile, Santiago, Chile
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6
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Mérai L, Deák Á, Dékány I, Janovák L. Fundamentals and utilization of solid/ liquid phase boundary interactions on functional surfaces. Adv Colloid Interface Sci 2022; 303:102657. [PMID: 35364433 DOI: 10.1016/j.cis.2022.102657] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 12/16/2022]
Abstract
The affinity of macroscopic solid surfaces or dispersed nano- and bioparticles towards liquids plays a key role in many areas from fluid transport to interactions of the cells with phase boundaries. Forces between solid interfaces in water become especially important when the surface texture or particles are in the colloidal size range. Although, solid-liquid interactions are still prioritized subjects of materials science and therefore are extensively studied, the related literature still lacks in conclusive approaches, which involve as much information on fundamental aspects as on recent experimental findings related to influencing the wetting and other wetting-related properties and applications of different surfaces. The aim of this review is to fill this gap by shedding light on the mechanism-of-action and design principles of different, state-of-the-art functional macroscopic surfaces, ranging from self-cleaning, photoreactive or antimicrobial coatings to emulsion separation membranes, as these surfaces are gaining distinguished attention during the ongoing global environmental and epidemic crises. As there are increasing numbers of examples for stimulus-responsive surfaces and their interactions with liquids in the literature, as well, this overview also covers different external stimulus-responsive systems, regarding their mechanistic principles and application possibilities.
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7
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Homage to Reptiles and Amphibians as Model Systems: One Ecologist's View. J HERPETOL 2022. [DOI: 10.1670/21-020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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8
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Baeckens S, Temmerman M, Gorb SN, Neto C, Whiting MJ, Van Damme R. Convergent evolution of skin surface microarchitecture and increased skin hydrophobicity in semi-aquatic anole lizards. J Exp Biol 2021; 224:272432. [PMID: 34642763 PMCID: PMC8541734 DOI: 10.1242/jeb.242939] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 09/10/2021] [Indexed: 11/23/2022]
Abstract
Animals that habitually cross the boundary between water and land face specific challenges with respect to locomotion, respiration, insulation, fouling and waterproofing. Many semi-aquatic invertebrates and plants have developed complex surface microstructures with water-repellent properties to overcome these problems, but equivalent adaptations of the skin have not been reported for vertebrates that encounter similar environmental challenges. Here, we document the first evidence of evolutionary convergence of hydrophobic structured skin in a group of semi-aquatic tetrapods. We show that the skin surface of semi-aquatic species of Anolis lizards is characterized by a more elaborate microstructural architecture (i.e. longer spines and spinules) and a lower wettability relative to closely related terrestrial species. In addition, phylogenetic comparative models reveal repeated independent evolution of enhanced skin hydrophobicity associated with the transition to a semi-aquatic lifestyle, providing evidence of adaptation. Our findings invite a new and exciting line of inquiry into the ecological significance, evolutionary origin and developmental basis of hydrophobic skin surfaces in semi-aquatic lizards, which is essential for understanding why and how the observed skin adaptations evolved in some and not other semi-aquatic tetrapod lineages. Summary: Multiple Anolis lineages independently evolved a similar skin surface microarchitecture with water-repellent properties as an adaptation to a semi-aquatic lifestyle.
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Affiliation(s)
- Simon Baeckens
- Laboratory for Functional Morphology, Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium.,Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia.,Laboratory for the Evolution and Optics of Nanostructures, Department of Biology, Ghent University, 9000 Gent,Belgium
| | - Marie Temmerman
- Laboratory for Functional Morphology, Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium
| | - Stanislav N Gorb
- Functional Morphology and Biomechanics, Zoological Institute of the Christian Albrecht Universität zu Kiel, Am Botanischen Garten 9, 24118 Kiel, Germany
| | - Chiara Neto
- School of Chemistry and Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia
| | - Martin J Whiting
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Raoul Van Damme
- Laboratory for Functional Morphology, Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium
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9
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Boccia CK, Swierk L, Ayala-Varela FP, Boccia J, Borges IL, Estupiñán CA, Martin AM, Martínez-Grimaldo RE, Ovalle S, Senthivasan S, Toyama KS, Del Rosario Castañeda M, García A, Glor RE, Mahler DL. Repeated evolution of underwater rebreathing in diving Anolis lizards. Curr Biol 2021; 31:2947-2954.e4. [PMID: 33984265 DOI: 10.1016/j.cub.2021.04.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/15/2021] [Accepted: 04/15/2021] [Indexed: 02/07/2023]
Abstract
Air-based respiration limits the use of aquatic environments by ancestrally terrestrial animals. To overcome this challenge, diving arthropods have evolved to respire without resurfacing using air held between their cuticle and surrounding water.1-4 Inspired by natural history observations in Haiti (unpublished data) and Costa Rica,5,6 we conducted experiments documenting routine air-based underwater respiration in several distantly related semi-aquatic Anolis lizard species. Semi-aquatic anoles live along neotropical streams and frequently dive for refuge or food,7-12 remaining underwater for up to 18 min. While submerged, these lizards iteratively expire and re-inspire narial air bubbles-underwater "rebreathing." Rebreathed air is used in respiration, as the partial pressure of oxygen in the bubbles decreases with experimental submersion time in living anoles, but not in mechanical controls. Non-aquatic anoles occasionally rebreathe when submerged but exhibit more rudimentary rebreathing behaviors. Anole rebreathing is facilitated by a thin air layer (i.e., a "plastron," sensu Brocher13) supported by the animal's rugose skin upon submergence. We suggest that hydrophobic skin, which we observed in all sampled anoles,14,15 may have been exaptative, facilitating the repeated evolution of specialized rebreathing in species that regularly dive. Phylogenetic analyses strongly suggest that specialized rebreathing is adaptive for semi-aquatic habitat specialists. Air-based rebreathing may enhance dive performance by incorporating dead space air from the buccal cavity or plastron into the lungs, facilitating clearance of carbon dioxide, or allowing uptake of oxygen from surrounding water (i.e., a "physical gill" mechanism4,16).
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Affiliation(s)
- Christopher K Boccia
- Department of Ecology and Evolutionary Biology, University of Toronto, ON M5S 3B2, Canada.
| | - Lindsey Swierk
- Department of Biological Sciences, Binghamton University, State University of New York, New York, NY 13902, USA; Environmental Studies Program, Binghamton University, State University of New York, New York, NY 13902, USA
| | - Fernando P Ayala-Varela
- Museo de Zoología, Escuela de Biología, Pontificia Universidad Católica del Ecuador, 12 de Octubre y Roca, Quito, Ecuador
| | - James Boccia
- Department of Ecology and Evolutionary Biology, University of Toronto, ON M5S 3B2, Canada
| | - Isabela L Borges
- Department of Integrative Biology, College of Natural Sciences, Michigan State University, East Lansing, MI 48824, USA; W.K. Kellogg Biological Station, Michigan State University, 3700 E. Gull Lake Drive, Hickory Corners, MI 49060, USA
| | - Camilo Andres Estupiñán
- Departamento de Ciencias Biológicas, Facultad de Ciencias Naturales, Universidad Icesi, Cali, Colombia
| | - Alexandra M Martin
- Department of Biological Sciences, Binghamton University, State University of New York, New York, NY 13902, USA
| | - Ramón E Martínez-Grimaldo
- Posgrado en Ciencias Biológicas, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Sebastian Ovalle
- Departamento de Ciencias Biológicas, Facultad de Ciencias Naturales, Universidad Icesi, Cali, Colombia
| | - Shreeram Senthivasan
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Ken S Toyama
- Department of Ecology and Evolutionary Biology, University of Toronto, ON M5S 3B2, Canada
| | | | - Andrés García
- Estación de Biología Chamela, Instituto de Biología, Universidad Nacional Autónoma de México, A.P. 21, San Patricio-Melaque, Jalisco, México
| | - Richard E Glor
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
| | - D Luke Mahler
- Department of Ecology and Evolutionary Biology, University of Toronto, ON M5S 3B2, Canada.
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10
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Riedel J, Zozaya SM, Hoskin CJ, Schwarzkopf L. Parallel evolution of toepads in rock-dwelling lineages of a terrestrial gecko (Gekkota: Gekkonidae: Heteronotia binoei). Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlaa167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Abstract
Selection for effective locomotion can lead to specialized morphological structures. Adhesive toepads, which have arisen independently in different lizard clades, facilitate the use of vertical and inverted substrates. Their evolution is poorly understood because functionally intermediate morphological configurations between padless and pad-bearing forms are rare. To shed light on toepad evolution, we assessed the subdigital morphology of phylogenetically distinct lineages of the Bynoe’s gecko species complex (Heteronotia binoei). Most populations of H. binoei are terrestrial, but two relatively distantly related saxicoline (rock-dwelling) lineages have enlarged terminal subdigital scales resembling toepads. We reconstructed the ancestral terminal subdigital scale size of nine lineages of H. binoei in eastern Australia, including these two saxicoline lineages. Additionally, we compared the subdigital microstructures of four lineages: the two saxicoline lineages and their respective terrestrial sister-lineages. Surprisingly, all four lineages had fully developed setae, but the setae of the two saxicoline lineages were significantly longer, branched more often and were more widely spaced than the terrestrial sister-lineages. We conclude that the saxicoline lineages represent examples of parallel evolution of enlarged adhesive structures in response to vertical substrate use, and their morphology represents a useful model as an intermediate state in toepad evolution.
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Affiliation(s)
- Jendrian Riedel
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - Stephen M Zozaya
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - Conrad J Hoskin
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - Lin Schwarzkopf
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
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