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Terrones-Ramírez AK, Robles-Bello SM, Vázquez-López M, Ramírez-Barrera SM, Zamudio-Beltrán LE, López López A, Arizmendi MDC, Durán-Suárez del Real AP, Eguiarte LE, Hernández-Baños BE. Recent genetic, phenetic and ecological divergence across the Mesoamerican highlands: a study case with Diglossa baritula (Aves: Thraupidae). PeerJ 2024; 12:e16797. [PMID: 38529306 PMCID: PMC10962342 DOI: 10.7717/peerj.16797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 12/24/2023] [Indexed: 03/27/2024] Open
Abstract
The topographical, geological, climatic and biodiversity complexity of Mesoamerica has made it a primary research focus. The Mesoamerican highlands is a region with particularly high species richness and within-species variation. The Cinnamon-bellied Flowerpiercer, Diglossa baritula (Wagler, 1832), is a species endemic to the Mesoamerican highlands, with three allopatric subspecies currently recognized. To characterize divergence within this species, we integrated genomics, morphology, coloration and ecological niche modeling approaches, obtained from sampling individuals across the entire geographic distribution of the species. Our results revealed a clear genomic divergence between the populations to the east versus the west of the Isthmus of Tehuantepec. In contrast to the genomic results, morphology and coloration analyses showed intermediate levels of differentiation, indicating that population groups within D. baritula have probably been under similar selective pressures. Our morphology results indicated that the only sexually dimorphic morphological variable is the wing chord, with males having a longer wing chord than females. Finally, ecological data indicated that there are differences in ecological niche within D. baritula. Our data suggest that D. baritula could contain two or more incipient species at the intermediate phase of the speciation continuum. These results highlight the importance of the geographical barrier of the Isthmus of Tehuantepec and Pleistocene climatic events in driving isolation and population divergence in D. baritula. The present investigation illustrates the speciation potential of the D. baritula complex and the capacity of Mesoamerican highlands to create cryptic biodiversity and endemism.
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Affiliation(s)
- Alondra K. Terrones-Ramírez
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
| | - Sahid M. Robles-Bello
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Melisa Vázquez-López
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Sandra M. Ramírez-Barrera
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Luz E. Zamudio-Beltrán
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Anuar López López
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Maria del Coro Arizmendi
- Laboratorio de Ecología, UBIPRO Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, Mexico
| | - Ana Paula Durán-Suárez del Real
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Luis E. Eguiarte
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
| | - Blanca E. Hernández-Baños
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de México, CdMx, Mexico
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2
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Straight PJ, Gignac PM, Kuenzel WJ. Mapping the avian visual tectofugal pathway using 3D reconstruction. J Comp Neurol 2024; 532:e25558. [PMID: 38047431 DOI: 10.1002/cne.25558] [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: 04/04/2023] [Revised: 06/19/2023] [Accepted: 10/17/2023] [Indexed: 12/05/2023]
Abstract
Image processing in amniotes is usually accomplished by the thalamofugal and/or tectofugal visual systems. In laterally eyed birds, the tectofugal system dominates with functions such as color and motion processing, spatial orientation, stimulus identification, and localization. This makes it a critical system for complex avian behavior. Here, the brains of chicks, Gallus gallus, were used to produce serial brain sections in either coronal, sagittal, or horizontal planes and stained with either Nissl and Gallyas silver myelin or Luxol fast blue stain and cresyl echt violet (CEV). The emerging techniques of diffusible iodine-based contrast-enhanced computed tomography (diceCT) coupled with serial histochemistry in three planes were used to generate a comprehensive three-dimensional (3D) model of the avian tectofugal visual system. This enabled the 3D reconstruction of tectofugal circuits, including the three primary neuronal projections. Specifically, major components of the system included four regions of the retina, layers of the optic tectum, subdivisions of the nucleus rotundus in the thalamus, the entopallium in the forebrain, and supplementary components connecting into or out of this major avian visual sensory system. The resulting 3D model enabled a better understanding of the structural components and connectivity of this complex system by providing a complete spatial organization that occupied several distinct brain regions. We demonstrate how pairing diceCT with traditional histochemistry is an effective means to improve the understanding of, and thereby should generate insights into, anatomical and functional properties of complicated neural pathways, and we recommend this approach to clarify enigmatic properties of these pathways.
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Affiliation(s)
- Parker J Straight
- Poultry Science Department, University of Arkansas, Fayetteville, Arkansas, USA
| | - Paul M Gignac
- Cellular and Molecular Medicine Department, University of Arizona Health Sciences, Tucson, Arizona, USA
- Anatomy and Cell Biology Department, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA
| | - Wayne J Kuenzel
- Poultry Science Department, University of Arkansas, Fayetteville, Arkansas, USA
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3
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Boycott TJ, Sherrard MG, Gall MD, Ronald KL. Deer management influences perception of avian plumage in temperate deciduous forests. Vision Res 2023; 213:108312. [PMID: 37703599 DOI: 10.1016/j.visres.2023.108312] [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] [Received: 01/29/2023] [Revised: 08/07/2023] [Accepted: 08/17/2023] [Indexed: 09/15/2023]
Abstract
Many animals use visual signals to communicate; birds use colorful plumage to attract mates and repel intruders. Visual signal conspicuousness is influenced by the lighting environment, which can be altered by human-induced changes. For example, deer-management efforts can affect vegetation structure and light availability. Whether these changes alter animal communication is still unknown. We investigated the effect of deer management on forest light and the contrast of understory birds against the forest background. We modeled visual perception using: (1) an ultraviolet-sensitive (UVS) avian model and plumage parameters representative of red, yellow, and blue birds (2) species-specific turkey visual and plumage parameters, and (3) individual-specific brown-headed cowbird visual and plumage parameters. Deer management led to greater light irradiance and lowered forest background reflectance. Management increased chromatic contrasts in the UVS model, primarily in deciduous forests and low understory, and across all habitat types in turkey and cowbird models. Deer management did not affect achromatic contrasts in the UVS model, but was associated with lower contrast in mixed forests for turkeys and across habitats for cowbirds. Together, this suggests that management of deer browsing is likely to impact visual signaling for a wide range of avian species. However, we also suspect that species- and individual-specific parameters increased the resolution of models, warranting consideration in future studies. Further work should determine if differences in visual perception translate to biologically relevant consequences. Our results suggest that, at least for some species, deer browsing and anthropogenic change may impose an evolutionary driver on visual communication.
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Affiliation(s)
- Timothy J Boycott
- Department of Biology, Vassar College, 124 Raymond Ave., Poughkeepsie, NY 12604, USA; New York Cooperative Fish and Wildlife Research Unit, Department of Natural Resources and the Environment, Cornell University, 226 Mann Drive, Ithaca, NY 14853, USA
| | - Morgan G Sherrard
- Department of Biology, Hope College, 35 East 12th Street, Holland, MI 49423, USA; University of Detroit Mercy School of Dentistry, 2700 Martin Luther King Jr. Blvd. Detroit, MI 48208-2576, USA
| | - Megan D Gall
- Department of Biology, Vassar College, 124 Raymond Ave., Poughkeepsie, NY 12604, USA; Neuroscience and Behavior Program, Vassar College, 124 Raymond Ave., Poughkeepsie, NY 12604, USA
| | - Kelly L Ronald
- Department of Biology, Hope College, 35 East 12th Street, Holland, MI 49423, USA.
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4
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Jones TM, Llamas AP, Phillips JN. Phenotypic signatures of urbanization? Resident, but not migratory, songbird eye size varies with urban-associated light pollution levels. GLOBAL CHANGE BIOLOGY 2023; 29:6635-6646. [PMID: 37728032 DOI: 10.1111/gcb.16935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 08/18/2023] [Accepted: 08/24/2023] [Indexed: 09/21/2023]
Abstract
Urbanization now exposes large portions of the earth to sources of anthropogenic disturbance, driving rapid environmental change and producing novel environments. Changes in selective pressures as a result of urbanization are often associated with phenotypic divergence; however, the generality of phenotypic change remains unclear. In this study, we examined whether morphological phenotypes in two residential species (Carolina Wren [Thryothorus ludovicianus] and Northern Cardinal [Cardinalis cardinalis]) and two migratory species (Painted Bunting [Passerina ciris], and White-eyed Vireo [Vireo griseus]), differed between urban core and edge habitats in San Antonio, Texas, USA. More specifically, we examined whether urbanization, associated sensory pollution (light and noise) and brightness (open, bright areas cause by anthropogenic land use) influenced measures of avian body (mass and frame size) and lateral eye size. We found no differences in body size between urban core and edge habitats for all species except the Painted Bunting, in which core-urban individuals were smaller. Rather than a direct effect of urbanization, this was due to differences in age structure between habitats, with urban-core areas consisting of higher proportions of younger buntings which are, on average, smaller than older birds. Residential birds inhabiting urban-core areas had smaller eyes compared to their urban-edge counterparts, resulting from a negative association between eye size and light pollution and brightness across study sites; notably, we found no such association in the two migratory species. Our findings demonstrate how urbanization may indirectly influence phenotypes by altering population demographics and highlight the importance of accounting for age when assessing factors driving phenotypic change. We also provide some of the first evidence that birds may adapt to urban environments through changes in their eye morphology, demonstrating the need for future research into relationships among eye size, ambient light microenvironment use, and disassembly of avian communities as a result of urbanization.
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Affiliation(s)
- Todd M Jones
- Department of Life Sciences, Texas A&M University-San Antonio, San Antonio, Texas, USA
- Migratory Bird Center, Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, USA
- Illinois Natural History Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, Illinois, USA
| | - Alfredo P Llamas
- Department of Life Sciences, Texas A&M University-San Antonio, San Antonio, Texas, USA
| | - Jennifer N Phillips
- Department of Life Sciences, Texas A&M University-San Antonio, San Antonio, Texas, USA
- School of the Environment, Washington State University, Pullman, Washington, USA
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5
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McLellan CF, Cuthill IC, Montgomery SH. Warning Coloration, Body Size, and the Evolution of Gregarious Behavior in Butterfly Larvae. Am Nat 2023; 202:64-77. [PMID: 37384762 DOI: 10.1086/724818] [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: 11/20/2023]
Abstract
AbstractMany species gain antipredator benefits by combining gregarious behavior with warning coloration, yet there is debate over which trait evolves first and which is the secondary adaptive enhancement. Body size can also influence how predators receive aposematic signals and potentially constrain the evolution of gregarious behavior. To our knowledge, the causative links between the evolution of gregariousness, aposematism, and larger body sizes have not been fully resolved. Here, using the most recently resolved butterfly phylogeny and an extensive new dataset of larval traits, we reveal the evolutionary interactions between important traits linked to larval gregariousness. We show that larval gregariousness has arisen many times across butterflies, and aposematism is a likely prerequisite for gregariousness to evolve. We also find that body size may be an important factor for determining the coloration of solitary, but not gregarious, larvae. Additionally, by exposing artificial larvae to wild avian predation, we show that undefended, cryptic larvae are heavily predated when aggregated but benefit from solitariness, whereas the reverse is true for aposematic prey. Our data reinforce the importance of aposematism for gregarious larval survival while identifying new questions about the roles of body size and toxicity in the evolution of grouping behavior.
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6
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Liu Y, Jiang Y, Xu J, Liao W. Evolution of Avian Eye Size Is Associated with Habitat Openness, Food Type and Brain Size. Animals (Basel) 2023; 13:ani13101675. [PMID: 37238105 DOI: 10.3390/ani13101675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/14/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
The eye is the primary sensory organ that obtains information from the ecological environments and specifically bridges the brain with the extra environment. However, the coevolutionary relationships between eye size and ecological factors, behaviours and brain size in birds remain poorly understood. Here, we investigate whether eye size evolution is associated with ecological factors (e.g., habitat openness, food type and foraging habitat), behaviours (e.g., migration and activity pattern) and brain size among 1274 avian species using phylogenetically controlled comparative analyses. Our results indicate that avian eye size is significantly associated with habitat openness, food type and brain size. Species living in dense habitats and consuming animals exhibit larger eye sizes compared to species living in open habitats and consuming plants, respectively. Large-brained birds tend to possess larger eyes. However, migration, foraging habitat and activity pattern were not found to be significantly associated with eye size in birds, except for nocturnal birds having longer axial lengths than diurnal ones. Collectively, our results suggest that avian eye size is primarily influenced by light availability, food need and cognitive ability.
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Affiliation(s)
- Yating Liu
- School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
| | - Ying Jiang
- School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
| | - Jiliang Xu
- School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
| | - Wenbo Liao
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong 637009, China
- Key Laboratory of Artificial Propagation and Utilization in Anurans of Nanchong City, China West Normal University, Nanchong 637009, China
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7
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Ontogenetic change in the effectiveness of camouflage: growth versus pattern matching in Fowler's toad. Anim Behav 2023. [DOI: 10.1016/j.anbehav.2023.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
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8
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Zhang J, Santema P, Lin Z, Yang L, Liu M, Li J, Deng W, Kempenaers B. Experimental evidence that cuckoos choose host nests following an egg matching strategy. Proc Biol Sci 2023; 290:20222094. [PMID: 36809803 PMCID: PMC9943643 DOI: 10.1098/rspb.2022.2094] [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] [Indexed: 02/23/2023] Open
Abstract
The arms race between brood parasites and their hosts provides a classic model to study coevolution. Hosts often reject the parasitic egg, and brood parasites should therefore select host nests in which the colour of the eggs best matches that of their own. Although this hypothesis has received some support, direct experimental evidence is still lacking. Here, we report on a study of Daurian redstarts, which show a distinct egg-colour dimorphism, with females laying either blue or pink eggs. Redstarts are often parasitized by common cuckoos, which lay light blue eggs. First, we showed that cuckoo eggs were more similar in spectral reflectance to the blue than to the pink redstart egg morph. Second, we report that the natural parasitism rate was higher in blue than in pink host clutches. Third, we performed a field experiment in which we presented a dummy clutch of each colour morph adjacent to active redstart nests. In this set-up, cuckoos almost always chose to parasitize a blue clutch. Our results demonstrate that cuckoos actively choose redstart nests in which the egg colour matches the colour of their own eggs. Our study thus provides direct experimental evidence in support of the egg matching hypothesis.
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Affiliation(s)
- Jinggang Zhang
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, People's Republic of China.,Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen 82319, Germany
| | - Peter Santema
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen 82319, Germany.,Edward Grey Institute, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Zixuan Lin
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Lixing Yang
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, People's Republic of China.,Academy of Forestry Inventory and Planning, National Forestry and Grassland Administration, Beijing 100714, People's Republic of China
| | - Meijun Liu
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Jianqiang Li
- School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, People's Republic of China
| | - Wenhong Deng
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Bart Kempenaers
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen 82319, Germany
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9
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Blount JD, Rowland HM, Mitchell C, Speed MP, Ruxton GD, Endler JA, Brower LP. The price of defence: toxins, visual signals and oxidative state in an aposematic butterfly. Proc Biol Sci 2023; 290:20222068. [PMID: 36651049 PMCID: PMC9845971 DOI: 10.1098/rspb.2022.2068] [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] [Indexed: 01/19/2023] Open
Abstract
In a variety of aposematic species, the conspicuousness of an individual's warning signal and the quantity of its chemical defence are positively correlated. This apparent honest signalling is predicted by resource competition models which assume that the production and maintenance of aposematic defences compete for access to antioxidant molecules that have dual functions as pigments and in protecting against oxidative damage. To test for such trade-offs, we raised monarch butterflies (Danaus plexippus) on different species of their milkweed host plants (Apocynaceae) that vary in quantities of cardenolides to test whether (i) the sequestration of cardenolides as a secondary defence is associated with costs in the form of oxidative lipid damage and reduced antioxidant defences; and (ii) lower oxidative state is associated with a reduced capacity to produce aposematic displays. In male monarchs conspicuousness was explained by an interaction between oxidative damage and sequestration: males with high levels of oxidative damage became less conspicuous with increased sequestration of cardenolides, whereas those with low oxidative damage became more conspicuous with increased levels of cardenolides. There was no significant effect of oxidative damage or concentration of sequestered cardenolides on female conspicuousness. Our results demonstrate a physiological linkage between the production of coloration and oxidative state, and differential costs of sequestration and signalling in monarch butterflies.
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Affiliation(s)
- Jonathan D. Blount
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall TR10 9FE, UK
| | - Hannah M. Rowland
- Research Group Predators and Toxic Prey, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, Jena, 07745, Germany
| | - Christopher Mitchell
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall TR10 9FE, UK
| | - Michael P. Speed
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7BE, UK
| | - Graeme D. Ruxton
- School of Biology, Sir Harold Mitchell Building, Greenside Place, St Andrews, UK
| | - John A. Endler
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | - Lincoln P. Brower
- Department of Biology, Sweet Briar College, Sweet Briar, VA 24595, USA
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10
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Hagen JFD, Roberts NS, Johnston RJ. The evolutionary history and spectral tuning of vertebrate visual opsins. Dev Biol 2023; 493:40-66. [PMID: 36370769 PMCID: PMC9729497 DOI: 10.1016/j.ydbio.2022.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 10/27/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022]
Abstract
Many animals depend on the sense of vision for survival. In eumetazoans, vision requires specialized, light-sensitive cells called photoreceptors. Light reaches the photoreceptors and triggers the excitation of light-detecting proteins called opsins. Here, we describe the story of visual opsin evolution from the ancestral bilaterian to the extant vertebrate lineages. We explain the mechanisms determining color vision of extant vertebrates, focusing on opsin gene losses, duplications, and the expression regulation of vertebrate opsins. We describe the sequence variation both within and between species that has tweaked the sensitivities of opsin proteins towards different wavelengths of light. We provide an extensive resource of wavelength sensitivities and mutations that have diverged light sensitivity in many vertebrate species and predict how these mutations were accumulated in each lineage based on parsimony. We suggest possible natural and sexual selection mechanisms underlying these spectral differences. Understanding how molecular changes allow for functional adaptation of animals to different environments is a major goal in the field, and therefore identifying mutations affecting vision and their relationship to photic selection pressures is imperative. The goal of this review is to provide a comprehensive overview of our current understanding of opsin evolution in vertebrates.
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Affiliation(s)
- Joanna F D Hagen
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Natalie S Roberts
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA.
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11
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Yorzinski JL, Troscianko J, Briolat E, Schapiro SJ, Whitham W. A songbird can detect the eyes of conspecifics under daylight and artificial nighttime lighting. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 313:120000. [PMID: 35995296 DOI: 10.1016/j.envpol.2022.120000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 07/25/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
Eyes convey important information about the external and internal worlds of animals. Individuals can follow the gaze of others to learn about the location of salient objects as well as assess eye qualities to evaluate the health, age or other internal states of conspecifics. Because of the increasing prevalence of artificial lighting at night (ALAN), urbanized individuals can potentially garner information from conspecific eyes under both daylight and ALAN. We tested this possibility using a visual modeling approach in which we estimated the maximum distance at which individuals could detect conspecific eyes under daylight and high levels of ALAN. We also estimated the minimum light level at which individuals could detect conspecific eyes. Great-tailed grackles (Quiscalus mexicanus) were used as our study species because they are highly social and are unusual among birds in that they regularly gather at nocturnal roosts in areas with high levels of ALAN. This visual modelling approach revealed that grackles can detect conspecific eyes under both daylight and ALAN, regardless of iris coloration. The grackles could detect conspecific eyes at farther distances in daylight compared to ALAN. Our results highlight the potential importance of lighting conditions in shaping social interactions.
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Affiliation(s)
- Jessica L Yorzinski
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, USA.
| | - Jolyon Troscianko
- Centre for Ecology & Conservation, University of Exeter, Penryn, United Kingdom
| | - Emmanuelle Briolat
- Centre for Ecology & Conservation, University of Exeter, Penryn, United Kingdom
| | - Steven J Schapiro
- Department of Comparative Medicine, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA
| | - Will Whitham
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, USA; Department of Comparative Medicine, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA
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12
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Luro AB, Hauber ME. Pressure for rapid and accurate mate recognition promotes avian-perceived plumage sexual dichromatism in true thrushes (genus: Turdus). J Evol Biol 2022; 35:1558-1567. [PMID: 36196886 PMCID: PMC9828161 DOI: 10.1111/jeb.14089] [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: 10/20/2021] [Revised: 07/26/2022] [Accepted: 08/06/2022] [Indexed: 01/12/2023]
Abstract
Ecological conditions limiting the time to find a compatible mate or increasing the difficulty in doing so likely promote the evolution of traits used for species and mate recognition. In addition to interspecific character displacement signalling species identity, intraspecific traits that signal an individual's sex and breeding status reduce the challenge of identifying a compatible conspecific mate and should be more common in migratory rather than sedentary species, species with shorter breeding seasons and species breeding under high sympatry with many closely related heterospecifics. Here, we tested this recognition hypothesis for promoting plumage sexual dichromatism in the true thrushes (Turdus spp.), a large and diverse genus of passerine birds. We used receptor-noise limited models of avian vision to quantify avian-perceived chromatic and achromatic visual contrasts between male and female plumage patches and tested the influence of breeding season length, spatial distribution and sympatry with other Turdus species on plumage dichromatism. As predicted, we found that (1) true thrush species with migratory behaviour have greater plumage sexual dichromatism than non-migratory species, (2) species with longer breeding seasons have less plumage sexual dichromatism, and (3) greater numbers of Turdus thrush species breeding in sympatry is associated with more plumage sexual dichromatism. These results suggest that social recognition systems, including species and mate recognition, play a prominent role in the evolution of plumage sexual dichromatism in true thrushes.
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Affiliation(s)
- Alec B. Luro
- Department of Evolution, Ecology, and Behavior, School of Integrative BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
| | - Mark E. Hauber
- Department of Evolution, Ecology, and Behavior, School of Integrative BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
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13
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Miller AE, Hogan BG, Stoddard MC. Color in motion: Generating 3-dimensional multispectral models to study dynamic visual signals in animals. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.983369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Analyzing color and pattern in the context of motion is a central and ongoing challenge in the quantification of animal coloration. Many animal signals are spatially and temporally variable, but traditional methods fail to capture this dynamism because they use stationary animals in fixed positions. To investigate dynamic visual displays and to understand the evolutionary forces that shape dynamic colorful signals, we require cross-disciplinary methods that combine measurements of color, pattern, 3-dimensional (3D) shape, and motion. Here, we outline a workflow for producing digital 3D models with objective color information from museum specimens with diffuse colors. The workflow combines multispectral imaging with photogrammetry to produce digital 3D models that contain calibrated ultraviolet (UV) and human-visible (VIS) color information and incorporate pattern and 3D shape. These “3D multispectral models” can subsequently be animated to incorporate both signaler and receiver movement and analyzed in silico using a variety of receiver-specific visual models. This approach—which can be flexibly integrated with other tools and methods—represents a key first step toward analyzing visual signals in motion. We describe several timely applications of this workflow and next steps for multispectral 3D photogrammetry and animation techniques.
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Rotov AY, Goriachenkov AA, Cherbunin RV, Firsov ML, Chernetsov N, Astakhova LA. Magnetoreceptory Function of European Robin Retina: Electrophysiological and Morphological Non-Homogeneity. Cells 2022; 11:cells11193056. [PMID: 36231018 PMCID: PMC9564291 DOI: 10.3390/cells11193056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 09/24/2022] [Accepted: 09/26/2022] [Indexed: 11/16/2022] Open
Abstract
The avian magnetic compass allows orientation during migration and is shown to function properly under short-wavelength but not long-wavelength visible light. Therefore, the magnetoreceptive system is assumed to be light- and wavelength-dependent and localized in the retina of the eye. Putative candidates for the role of primary magnetosensory molecules are the cryptochromes that are known to be expressed in the avian retina and must be able to interact with phototransduction proteins. Previously, we reported that in migratory birds change in magnetic field direction induces significant effects on electroretinogram amplitude in response to blue flashes, and such an effect was observed only in the nasal quadrant of the retina. Here, we report new electroretinographic, microscopic and microspectrophotometric data on European robins, confirming the magnetosensitivity of the retinal nasal quadrant after applying the background illumination. We hypothesized that magnetoreceptive distinction of this region may be related to its morphology and analyzed the retinal distribution and optical properties of oil droplets, the filtering structures within cones. We found that the nasal quadrant contains double cones with the most intensely colorized oil droplets compared to the rest of the retina, which may be related to its magnetosensory function.
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Affiliation(s)
- Alexander Yu. Rotov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
| | - Arsenii A. Goriachenkov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
| | - Roman V. Cherbunin
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
- Spin Optics Laboratory, Physics Faculty, St. Petersburg State University, 198504 St. Petersburg, Russia
| | - Michael L. Firsov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
| | - Nikita Chernetsov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
- Department of Vertebrate Zoology, Biological Faculty, St. Petersburg State University, 199034 St. Petersburg, Russia
- Ornithology Lab, Zoological Institute RAS, 199034 St. Petersburg, Russia
| | - Luba A. Astakhova
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
- Correspondence:
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15
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de Alcantara Viana JV, Lourenço Garcia de Brito V, de Melo C. Colour matching by arthropods in burned and unburned backgrounds in a Neotropical savanna. AUSTRAL ECOL 2022. [DOI: 10.1111/aec.13225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- João Vitor de Alcantara Viana
- Programa de Pós‐Graduação em Ecologia e Conservação de Recursos Naturais, Laboratório de Ornitologia e Bioacústica Universidade Federal de Uberlândia (UFU) Uberlândia Brazil
- Programa de Pós‐Graduação em Ecologia, Laboratório de Interações Multitróficas e Biodiversidade, Instituto de Biologia Universidade Estadual de Campinas (UNICAMP) Campinas
- Laboratório de Interações Multitróficas e Biodiversidade Departamento de Biologia Animal, Instituto de Biologia Universidade Estadual de Campinas CP 6109, CEP 13083-970 Campinas São Paulo Brazil
| | | | - Celine de Melo
- Instituto de Biologia Universidade Federal de Uberlândia Uberlândia Brazil
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16
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Šulc M, Hughes AE, Mari L, Troscianko J, Tomášek O, Albrecht T, Jelínek V. Nest sanitation as an effective defence against brood parasitism. Anim Cogn 2022; 25:991-1002. [PMID: 35778546 DOI: 10.1007/s10071-022-01646-0] [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: 01/31/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 11/28/2022]
Abstract
Egg rejection is a crucial defence strategy against brood parasitism that requires the host to correctly recognise the foreign egg. Rejection behaviour has, thus, evolved in many hosts, facilitated by the visual differences between the parasitic and host eggs, and driving hosts to rely on colour and pattern cues. On the other hand, the need to recognise non-egg-shaped objects to carry out nest sanitation led birds to evolve the ability to discriminate and eject objects using mainly shape cues. However, little is known regarding the evolutionary significance of rejection behaviour in general and the cognitive processes underlying it. Here, we investigated the response of the barn swallow (Hirundo rustica) during pre-laying and laying stages to four objects types that differed in shape (eggs vs stars) and colour/pattern (mimetic vs non-mimetic) to investigate (1) what cognitive mechanisms are involved in object discrimination and (2) whether egg rejection is a direct defence against brood parasitism, or simply a product of nest sanitation. We found that swallows ejected stars more often than eggs in both stages, indicating that swallows possess a template for the shape of their eggs. Since the effect of colour/pattern on ejection decisions was minor, we suggest that barn swallows have not evolved a direct defence against brood parasitism but instead, egg ejection might be a product of their well-developed nest sanitation behaviour. Nonetheless, the fact that mimetic eggs were ejected especially in the pre-laying stage shows that nest sanitation could be an effective defence against poorly timed brood parasitism.
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Affiliation(s)
- Michal Šulc
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic.
| | - Anna E Hughes
- Department of Psychology, University of Essex, Colchester, UK
| | - Lisandrina Mari
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
| | - Jolyon Troscianko
- Centre for Life and Environmental Sciences, University of Exeter, Penryn, UK
| | - Oldřich Tomášek
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic.,Department of Zoology, Masaryk University, Brno, Czech Republic
| | - Tomáš Albrecht
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic.,Department of Zoology, Charles University, Prague, Czech Republic
| | - Václav Jelínek
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
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17
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Silva DJA, Erickson MF, dos Santos Guidi R, Pessoa DMA. Thin-fingered fiddler crabs display a natural preference for UV light cues but show no sensory bias to other hypertrophied claw coloration. Behav Processes 2022; 200:104667. [DOI: 10.1016/j.beproc.2022.104667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 05/06/2022] [Accepted: 05/30/2022] [Indexed: 12/27/2022]
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18
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Chetverikova R, Dautaj G, Schwigon L, Dedek K, Mouritsen H. Double cones in the avian retina form an oriented mosaic which might facilitate magnetoreception and/or polarized light sensing. J R Soc Interface 2022; 19:20210877. [PMID: 35414212 PMCID: PMC9006000 DOI: 10.1098/rsif.2021.0877] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To navigate between breeding and wintering grounds, night-migratory songbirds are aided by a light-dependent magnetic compass sense and maybe also by polarized light vision. Although the underlying mechanisms for magnetoreception and polarized light sensing remain unclear, double cone photoreceptors in the avian retina have been suggested to represent the primary sensory cells. To use these senses, birds must be able to separate the directional information from the Earth's magnetic field and/or light polarization from variations in light intensity. Theoretical considerations suggest that this could be best achieved if neighbouring double cones were oriented in an ordered pattern. Therefore, we investigate the orientation patterns of double cones in European robins (Erithacus rubecula) and domestic chickens (Gallus gallus domesticus). We used whole-mounted retinas labelled with double cone markers to quantify the orientations of individual double cones in relation to their nearest neighbours. In both species, our data show that the double cone array is highly ordered: the angles between neighbouring double cones were more likely to be 90°/-90° in the central retina and 180°/0° in the peripheral retina, respectively. The observed regularity in double cone orientation could aid the cells' putative function in light-dependent magnetoreception and/or polarized light sensing.
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Affiliation(s)
- Raisa Chetverikova
- Animal Navigation/Neurosensorics Group, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
| | - Glen Dautaj
- Animal Navigation/Neurosensorics Group, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
| | - Leonard Schwigon
- Animal Navigation/Neurosensorics Group, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
| | - Karin Dedek
- Animal Navigation/Neurosensorics Group, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany.,Research Center Neurosensory Science, University of Oldenburg, Oldenburg, Germany
| | - Henrik Mouritsen
- Animal Navigation/Neurosensorics Group, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany.,Research Center Neurosensory Science, University of Oldenburg, Oldenburg, Germany
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Cheney KL, Hudson J, de Busserolles F, Luehrmann M, Shaughnessy A, van den Berg C, Green NF, Marshall NJ, Cortesi F. Seeing Picasso: an investigation into the visual system of the triggerfish Rhinecanthus aculeatus. J Exp Biol 2022; 225:jeb243907. [PMID: 35244167 PMCID: PMC9080752 DOI: 10.1242/jeb.243907] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 02/25/2022] [Indexed: 11/20/2022]
Abstract
Vision is used by animals to find food and mates, avoid predators, defend resources and navigate through complex habitats. Behavioural experiments are essential for understanding animals' perception but are often challenging and time-consuming; therefore, using species that can be trained easily for complex tasks is advantageous. Picasso triggerfish, Rhinecanthus aculeatus, have been used in many behavioural studies investigating vision and navigation. However, little is known about the molecular and anatomical basis of their visual system. We addressed this knowledge gap here and behaviourally tested achromatic and chromatic acuity. In terms of visual opsins, R. aculeatus possessed one rod opsin gene (RH1) and at least nine cone opsins: one violet-sensitive SWS2B gene, seven duplicates of the blue-green-sensitive RH2 gene (RH2A, RH2B, RH2C1-5) and one red-sensitive LWS gene. However, only five cone opsins were expressed: SWS2B expression was consistent, while RH2A, RH2C-1 and RH2C-2 expression varied depending on whether fish were sampled from the field or aquaria. Levels of LWS expression were very low. Using fluorescence in situ hybridisation, we found SWS2B was expressed exclusively in single cones, whereas RH2A and RH2Cs were expressed in opposite double cone members. Anatomical resolution estimated from ganglion cell densities was 6.8 cycles per degree (cpd), which was significantly higher than values obtained from behavioural testing for black-and-white achromatic stimuli (3.9 cpd) and chromatic stimuli (1.7-1.8 cpd). These measures were twice as high as previously reported. This detailed information on their visual system will help inform future studies with this emerging focal species.
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Affiliation(s)
- Karen L. Cheney
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Jemma Hudson
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Fanny de Busserolles
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Martin Luehrmann
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Abigail Shaughnessy
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Cedric van den Berg
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Naomi F. Green
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - N. Justin Marshall
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Fabio Cortesi
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
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20
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Yeager J, Barnett JB. Continuous Variation in an Aposematic Pattern Affects Background Contrast, but Is Not Associated With Differences in Microhabitat Use. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.803996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Variation in aposematic signals was once predicted to be rare, yet in recent years it has become increasingly well documented. Despite increases in the frequency with which polytypism and polymorphism have been suggested to occur, population-wide variance is rarely quantified. We comprehensively sampled a subpopulation of the poison frog Oophaga sylvatica, a species which is polytypic across its distribution and also shows considerable within-population polymorphism. On one hand, color pattern polymorphism could be the result of multifarious selection acting to balance different signaling functions and leading to the evolution of discrete sub-morphs which occupy different fitness peaks. Alternatively, variance could simply be due to relaxed selection, where variation would be predicted to be continuous. We used visual modeling of conspecific and heterospecific observers to quantify the extent of within population phenotypic variation and assess whether this variation produced distinct signals. We found that, despite considerable color pattern variation, variance could not be partitioned into distinct groups, but rather all viewers would be likely to perceive variation as continuous. Similarly, we found no evidence that frog color pattern contrast was either enhanced or diminished in the frogs’ chosen microhabitats compared to alternative patches in which conspecifics were observed. Within population phenotypic variance therefore does not seem to be indicative of strong selection toward multiple signaling strategies, but rather pattern divergence has likely arisen due to weak purifying selection, or neutral processes, on a signal that is highly salient to both conspecifics and predators.
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21
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Wang B, Yu L, Ma N, Zhang Z, Gong D, Liu R, Li D, Zhang S. Conspicuous cruciform silk decorations deflect avian predator attacks. Integr Zool 2021; 17:689-703. [PMID: 34958514 DOI: 10.1111/1749-4877.12621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although camouflage as an effective antipredator defence strategy is widespread across animals, highly conspicuous color patterning is not uncommon either. Many orb-web spiders adorn their webs with extra, bright white silk. These conspicuous decorations are hypothesized to deter predators by warning the presence of sticky webs, camouflaging spiders, acting as a decoy, or intimidating predators by their apparent size. The decorations may also deflect predator attacks from spiders. However, empirical evidence for this deflection function remains limited. Here we tested this hypothesis using the X-shaped silk cruciform decorations built by females of Argiope minuta. We employed visual modelling to quantify the conspicuousness of spiders and decorations from a perspective of avian predators. Then we determined actual predation risk on spiders using naïve chicks as predators. Spider bodies and decorations were conspicuous against natural backgrounds to the avian visual systems. Chicks attacked the spider main bodies significantly less frequently on the decorated webs than on the undecorated webs, thus reducing predation risk. When both spiders and decorations were present, chicks also attacked the spider main bodies and their legs or decorations, and not randomly: they attacked the legs or decorations sooner and more frequently than they attacked the main bodies, independence of the ratio of the surface area between the decoration and spider size. Despite the increase in detectability, incorporating a conspicuous cruciform decoration to the web effectively defends the spider by diverting the attack towards the decoration or leg, but not by camouflaging or intimidating, thus, supporting the deflection hypothesis. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Bingjun Wang
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China
| | - Long Yu
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China.,Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543
| | - Nina Ma
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China
| | - Zengtao Zhang
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China
| | - Deyong Gong
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China
| | - Rui Liu
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China
| | - Daiqin Li
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543
| | - Shichang Zhang
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China
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22
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Victory N, Segovia Y, García M. Cone distribution and visual resolution of the yellow-legged gull, Larus michahellis (Naumann, 1840). Anat Histol Embryol 2021; 51:197-214. [PMID: 34939688 DOI: 10.1111/ahe.12779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 10/21/2021] [Accepted: 11/27/2021] [Indexed: 01/21/2023]
Abstract
The morphological characteristics of the yellow-legged gull's photoreceptors and cone distribution were studied using light and electron microscopy. In wholemount fresh retinas, five different coloured oil droplets located in the cone inner segments could be seen and characterized by colour, diameter and stratification. The photoreceptors were classified by comparing the fresh and fixed vertical sections under a light and electron microscope. Rods were easily distinguished from cones based on the outer segment morphology and the absence of oil droplets in their inner segments. Four types of single cones were associated with red, yellow, colourless and transparent oil droplets. Unequal double cones comprised a long principal member with a green oil droplet and an accessory short member containing a green microdroplet which was highly electron-dense under electron microscopy. The different types of oil droplets were counted from microphotographs of fresh retinal samples in 20 regions. The density, percentage and diameter of the oil droplets were determined. The results showed that central regions had the highest oil droplet density which decreased towards the retinal periphery in all quadrants. Moreover, the oil droplet density was higher in the dorsotemporal quadrant than in other retinal regions. The average density of the red oil droplets was highest in the central areas, whereas colourless oil droplets had the highest density throughout the retina. In contrast, transparent oil droplets had the lowest density across all the regions of the retina. Finally, the retinal resolution was 52.61 cycles/degree. It was calculated using the posterior nodal distance and the oil droplet diameter. The work concludes by discussing the significance of the relative proportion of different cone types across the retina.
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Affiliation(s)
- Noemi Victory
- Department of Biotechnology, Faculty of Science, University of Alicante, Alicante, Spain
| | - Yolanda Segovia
- Department of Biotechnology, Faculty of Science, University of Alicante, Alicante, Spain
| | - Magdalena García
- Department of Biotechnology, Faculty of Science, University of Alicante, Alicante, Spain
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23
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Pinna CS, Vilbert M, Borensztajn S, Daney de Marcillac W, Piron-Prunier F, Pomerantz A, Patel NH, Berthier S, Andraud C, Gomez D, Elias M. Mimicry can drive convergence in structural and light transmission features of transparent wings in Lepidoptera. eLife 2021; 10:e69080. [PMID: 34930525 PMCID: PMC8691843 DOI: 10.7554/elife.69080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 11/19/2021] [Indexed: 01/30/2023] Open
Abstract
Müllerian mimicry is a positive interspecific interaction, whereby co-occurring defended prey species share a common aposematic signal. In Lepidoptera, aposematic species typically harbour conspicuous opaque wing colour patterns with convergent optical properties among co-mimetic species. Surprisingly, some aposematic mimetic species have partially transparent wings, raising the questions of whether optical properties of transparent patches are also convergent, and of how transparency is achieved. Here, we conducted a comparative study of wing optics, micro and nanostructures in neotropical mimetic clearwing Lepidoptera, using spectrophotometry and microscopy imaging. We show that transparency, as perceived by predators, is convergent among co-mimics in some mimicry rings. Underlying micro- and nanostructures are also sometimes convergent despite a large structural diversity. We reveal that while transparency is primarily produced by microstructure modifications, nanostructures largely influence light transmission, potentially enabling additional fine-tuning in transmission properties. This study shows that transparency might not only enable camouflage but can also be part of aposematic signals.
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Affiliation(s)
- Charline Sophie Pinna
- Institut de Systématique, Evolution, Biodiversité (ISYEB), CNRS, Muséum national d'Histoire naturelle, Sorbonne Université, EPHE, Université des AntillesParisFrance
| | - Maëlle Vilbert
- Centre de Recherche sur la Conservation (CRC), CNRS, MNHN, Ministère de la CultureParisFrance
| | - Stephan Borensztajn
- Institut de Physique du Globe de Paris (IPGP), Université de Paris, CNRSParisFrance
| | | | - Florence Piron-Prunier
- Institut de Systématique, Evolution, Biodiversité (ISYEB), CNRS, Muséum national d'Histoire naturelle, Sorbonne Université, EPHE, Université des AntillesParisFrance
| | - Aaron Pomerantz
- Marine Biological LaboratoryWoods HoleUnited States
- Department Integrative Biology, University of California BerkeleyBerkeleyUnited States
| | | | - Serge Berthier
- Institut des NanoSciences de Paris (INSP), Sorbonne Université, CNRSParisFrance
| | - Christine Andraud
- Centre de Recherche sur la Conservation (CRC), CNRS, MNHN, Ministère de la CultureParisFrance
| | - Doris Gomez
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), CNRS, Univ MontpellierMontpellierFrance
| | - Marianne Elias
- Institut de Systématique, Evolution, Biodiversité (ISYEB), CNRS, Muséum national d'Histoire naturelle, Sorbonne Université, EPHE, Université des AntillesParisFrance
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24
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Ontogenetic colour change of a sexual ornament in males of a damselfly: female mimicry, crypsis or both? Naturwissenschaften 2021; 109:2. [PMID: 34874492 DOI: 10.1007/s00114-021-01775-5] [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: 10/18/2021] [Revised: 11/25/2021] [Accepted: 11/29/2021] [Indexed: 10/19/2022]
Abstract
Female mimicry by males is a widespread phenomenon in several taxa and may be involved in aggression avoidance or facilitated access to resources. In early developmental stages, female mimicry may be a mechanism involved in signalling sexual immaturity or, when coupled with strategies related to visual camouflage, may be involved in the avoidance of male-male agonistic interactions. Here, we addressed whether the delayed colour maturation of a sexual ornament in males of Mnesarete pudica damselflies might be a case of crypsis, female mimicry or both. We analysed how conspecifics and predators perceive the pigmented wings of juvenile males by contrasting the wing spectra against a savannah background and the wings of both juvenile and sexually mature males and females. Our results based on the modelled visual system of conspecifics and predators suggest that the colour maturation of juvenile males may function as both crypsis and female mimicry. We discuss whether these results related to age- and sexual-dichromatism might be a mechanism to avoid unwanted intraspecific interactions or to avoid territorial and aggressive males. We conclude that the female mimicry and crypsis in juvenile males of M. pudica are mechanisms involved in avoidance of predators and unwanted intraspecific interactions, and the signalling of sexual maturity.
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25
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Rojas Ripari JM, Ursino CA, Reboreda JC, De Mársico MC. Tricking Parents: A Review of Mechanisms and Signals of Host Manipulation by Brood-Parasitic Young. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.725792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Obligate avian brood parasites depend entirely on heterospecific hosts for rearing their offspring. From hatching until independence, the young parasites must deal with the challenge of obtaining sufficient parental care from foster parents that are attuned to provisioning their own offspring. Parent-offspring communication is mediated by complex begging displays in which nestlings and fledglings exhibit visual (e.g., gaping and postures) and vocal (e.g., begging calls) traits that serve as signals to parents to adjust and allocate parental effort. Parasites can manipulate host parental behavior by exploiting these stable parent-offspring communication systems in their favor. During the past 30 years, the study of host exploitation by parasitic chicks has yielded important insights into the function and evolution of manipulative signals in brood parasites. However, despite these major advances, there are still important gaps in our knowledge about how parasitic nestling and fledglings tune into the host’s communication channels and the adaptive value of the visual and acoustic signals they exhibit. Here we review the literature pertaining to host manipulation by parasitic young, focusing on four non-mutually exclusive mechanisms (i.e., host chick mimicry, begging exaggeration, host-attuned begging calls, and sensory exploitation) and the function and evolution of the signals involved, with the aim to summarize and discuss putative adaptations for stimulating parental feeding and escaping host discrimination. Finally, we bring some concluding remarks and suggest directions for future research on the ways in which brood parasites adapt to the communication systems of other birds to exploit the necessary parental care.
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26
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Ogilvie JG, Van Belleghem S, Range R, Papa R, McMillan OW, Chouteau M, Counterman BA. Balanced polymorphisms and their divergence in a Heliconius butterfly. Ecol Evol 2021; 11:18319-18330. [PMID: 35003675 PMCID: PMC8717333 DOI: 10.1002/ece3.8423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/15/2021] [Accepted: 11/19/2021] [Indexed: 11/10/2022] Open
Abstract
The evolution of mimicry in similarly defended prey is well described by the Müllerian mimicry theory, which predicts the convergence of warning patterns in order to gain the most protection from predators. However, despite this prediction, we can find great diversity of color patterns among Müllerian mimics such as Heliconius butterflies in the neotropics. Furthermore, some species have evolved the ability to maintain multiple distinct warning patterns in single populations, a phenomenon known as polymorphic mimicry. The adaptive benefit of these polymorphisms is questionable since variation from the most common warning patterns is expected to be disadvantageous as novel signals are punished by predators naive to them. In this study, we use artificial butterfly models throughout Central and South America to characterize the selective pressures maintaining polymorphic mimicry in Heliconius doris. Our results highlight the complexity of positive frequency-dependent selection, the principal selective pressure driving convergence among Müllerian mimics, and its impacts on interspecific variation of mimetic warning coloration. We further show how this selection regime can both limit and facilitate the diversification of mimetic traits.
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Affiliation(s)
- James G. Ogilvie
- Department of Biological SciencesAuburn UniversityAuburnAlabamaUSA
- Smithsonian Tropical Research InstitutePanama CityPanama
| | | | - Ryan Range
- Department of Biological SciencesAuburn UniversityAuburnAlabamaUSA
| | - Riccardo Papa
- Department of BiologyUniversity of Puerto RicoRio PiedrasPuerto Rico
| | | | - Mathieu Chouteau
- Laboratoire Écologie, Évolution, Interactions des Systèmes Amazoniens (LEEISA)Université de GuyaneCNRSIFREMERCayenneFrench Guiana
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27
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Rowe ZW, Austin DJD, Chippington N, Flynn W, Starkey F, Wightman EJ, Scott-Samuel NE, Cuthill IC. Background complexity can mitigate poor camouflage. Proc Biol Sci 2021; 288:20212029. [PMID: 34814749 PMCID: PMC8611345 DOI: 10.1098/rspb.2021.2029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 11/02/2021] [Indexed: 11/12/2022] Open
Abstract
Avoiding detection through camouflage is often key to survival. However, an animal's appearance is not the only factor affecting conspicuousness: background complexity also alters detectability. This has been experimentally demonstrated for both artificially patterned backgrounds in the laboratory and natural backgrounds in the wild, but only for targets that already match the background well. Do habitats of high visual complexity provide concealment to even relatively poorly camouflaged animals? Using artificial prey which differed in their degrees of background matching to tree bark, we were able to determine their survival, under bird predation, with respect to the natural complexity of the background. The latter was quantified using low-level vision metrics of feature congestion (or 'visual clutter') adapted for bird vision. Higher background orientation clutter (edges with varying orientation) reduced the detectability of all but the poorest background-matching camouflaged treatments; higher background luminance clutter (varying achromatic lightness) reduced average mortality for all treatments. Our results suggest that poorer camouflage can be mitigated by more complex backgrounds, with implications for both camouflage evolution and habitat preferences.
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Affiliation(s)
- Zeke W. Rowe
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Daniel J. D. Austin
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Nicol Chippington
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - William Flynn
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Finn Starkey
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Edward J. Wightman
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | | | - Innes C. Cuthill
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
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28
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Nokelainen O, de Moraes Rezende F, Valkonen JK, Mappes J. Context-dependent coloration of prey and predator decision making in contrasting light environments. Behav Ecol 2021; 33:77-86. [PMID: 35197807 PMCID: PMC8857938 DOI: 10.1093/beheco/arab111] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 08/17/2021] [Accepted: 09/15/2021] [Indexed: 12/01/2022] Open
Abstract
A big question in behavioral ecology is what drives diversity of color signals. One possible explanation is that environmental conditions, such as light environment, may alter visual signaling of prey, which could affect predator decision-making. Here, we tested the context-dependent predator selection on prey coloration. In the first experiment, we tested detectability of artificial visual stimuli to blue tits (Cyanistes caeruleus) by manipulating stimulus luminance and chromatic context of the background. We expected the presence of the chromatic context to facilitate faster target detection. As expected, blue tits found targets on chromatic yellow background faster than on achromatic grey background whereas in the latter, targets were found with smaller contrast differences to the background. In the second experiment, we tested the effect of two light environments on the survival of aposematic, color polymorphic wood tiger moth (Arctia plantaginis). As luminance contrast should be more detectable than chromatic contrast in low light intensities, we expected birds, if they find the moths aversive, to avoid the white morph which is more conspicuous than the yellow morph in low light (and vice versa in bright light). Alternatively, birds may attack first moths that are more detectable. We found birds to attack yellow moths first in low light conditions, whereas white moths were attacked first more frequently in bright light conditions. Our results show that light environments affect predator foraging decisions, which may facilitate context-dependent selection on visual signals and diversity of prey phenotypes in the wild.
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Affiliation(s)
- Ossi Nokelainen
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Francisko de Moraes Rezende
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Janne K Valkonen
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Johanna Mappes
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikki Biocenter 3, Helsinki, Finland
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29
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Olsson P, Lind O, Mitkus M, Delhey K, Kelber A. Lens and cornea limit UV vision of birds - a phylogenetic perspective. J Exp Biol 2021; 224:jeb243129. [PMID: 34581400 PMCID: PMC8601714 DOI: 10.1242/jeb.243129] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/21/2021] [Indexed: 12/03/2022]
Abstract
Most vertebrates have UV-sensitive vision, but the UV sensitivity of their eyes is limited by the transmittance of the ocular media, and the specific contribution of the different media (cornea, lens) has remained unclear. Here, we describe the transmittance of all ocular media (OMT), as well as that of lenses and corneas of birds. For 66 species belonging to 18 orders, the wavelength at which 50% of light is transmitted through the ocular media to the retina (λT0.5) ranges from 310 to 398 nm. Low λT0.5 corresponds to more UV light transmitted. Corneal λT0.5 varies only between 300 and 345 nm, whereas lens λT0.5 values are more variable (between 315 and 400 nm) and tend to be the limiting factor, determining OMT in the majority of species. OMT λT0.5 is positively correlated with eye size, but λT0.5 of corneas and lenses are not correlated with their thickness when controlled for phylogeny. Corneal and lens transmittances do not differ between birds with UV- and violet-sensitive SWS1 opsin when controlling for eye size and phylogeny. Phylogenetic relatedness is a strong predictor of OMT, and ancestral state reconstructions suggest that from ancestral intermediate OMT, highly UV-transparent ocular media (low λT0.5) evolved at least five times in our sample of birds. Some birds have evolved in the opposite direction towards a more UV-opaque lens, possibly owing to pigmentation, likely to mitigate UV damage or reduce chromatic aberration.
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Affiliation(s)
- Peter Olsson
- Department of Biology, Lund University, 22362 Lund, Sweden
| | - Olle Lind
- Department of Biology, Lund University, 22362 Lund, Sweden
- Department of Philosophy, Lund University, 22100 Lund, Sweden
| | | | - Kaspar Delhey
- Max Planck Institute for Ornithology, 78315 Seewiesen, Germany
- School of Biological Sciences, Monash University, 3800 Clayton, Victoria, Australia
| | - Almut Kelber
- Department of Biology, Lund University, 22362 Lund, Sweden
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30
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Arias M, Leroy L, Madec C, Matos L, Tedore C, Elias M, Gomez D. Partial wing transparency works better when disrupting wing edges: Evidence from a field experiment. J Evol Biol 2021; 34:1840-1846. [PMID: 34601773 DOI: 10.1111/jeb.13943] [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: 05/27/2021] [Revised: 09/04/2021] [Accepted: 09/19/2021] [Indexed: 11/28/2022]
Abstract
Lepidoptera-a group of insects in which wing transparency has arisen multiple times-exhibits much variation in the size and position of transparent wing zones. However, little is known as to how this variability affects detectability. Here, we test how the size and position of transparent elements affect the predation of artificial moths by wild birds in the field. Morphs with transparent elements touching wing borders showed a reduced predation risk, with the effect being the same regardless of the number of wing borders being touched. By contrast, transparent element size had little to no effect on predation risk. Overall, this experiment shows for the first time that transparency offers higher protection when it disrupts prey contour in terrestrial habitats.
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Affiliation(s)
- Mónica Arias
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Montpellier, France.,ISYEB, CNRS, MNHN, Sorbonne Univ, EPHE, Univ. Antilles, 45 rue Buffon CP50, Paris, France
| | - Lucie Leroy
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Montpellier, France
| | - Clément Madec
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Montpellier, France
| | - Louane Matos
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Montpellier, France
| | - Cynthia Tedore
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Montpellier, France.,Faculty of Mathematics, Informatics and Natural Sciences, Institute of Zoology, Univ. Hamburg, Hamburg, Germany
| | - Marianne Elias
- ISYEB, CNRS, MNHN, Sorbonne Univ, EPHE, Univ. Antilles, 45 rue Buffon CP50, Paris, France
| | - Doris Gomez
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Montpellier, France.,INSP, CNRS, Sorbonne Univ., Paris, France
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31
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Yeager J, Barnett JB. The influence of ultraviolet reflectance differs between conspicuous aposematic signals in neotropical butterflies and poison frogs. Ecol Evol 2021; 11:13633-13640. [PMID: 34707805 PMCID: PMC8525173 DOI: 10.1002/ece3.7942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 11/07/2022] Open
Abstract
Warning signals are often characterized by highly contrasting, distinctive, and memorable colors. Greater chromatic (hue) and achromatic (brightness) contrast have both been found to contribute to greater signal efficacy, making longwave colored signals (e.g., red and yellow), that are perceived by both chromatic and achromatic visual pathways, particularly common. Conversely, shortwave colors (e.g., blue and ultraviolet) do not contribute to luminance perception yet are also commonly found in warning signals. Our understanding of the role of UV in aposematic signals is currently incomplete as UV perception is not universal, and evidence for its utility is at best mixed. We used visual modeling to quantify how UV affects signal contrast in aposematic heliconiian butterflies and poison frogs both of which reflect UV wavelengths, occupy similar habitats, and share similar classes of predators. Previous work on butterflies has found that UV reflectance does not affect predation risk but is involved in mate choice. As the butterflies, but not the frogs, have UV-sensitive vision, the function of UV reflectance in poison frogs is currently unknown. We found that despite showing up strongly in UV photographs, UV reflectance only appreciably affected visual contrast in the butterflies. As such, these results support the notion that although UV reflectance is associated with intraspecific communication in butterflies, it appears to be nonfunctional in frogs. Consequently, our data highlight that we should be careful when assigning a selection-based benefit to the presence of UV reflectance.
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Affiliation(s)
- Justin Yeager
- Biodiversidad Medio Ambiente y Salud Universidad de Las Américas Quito Ecuador
| | - James B Barnett
- Psychology, Neuroscience & Behaviour McMaster University Hamilton ON Canada
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32
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Guidi RDS, São-Pedro VDA, da Silva HR, Costa GC, Pessoa DMA. The trade-off between color and size in lizards' conspicuous tails. Behav Processes 2021; 192:104496. [PMID: 34492324 DOI: 10.1016/j.beproc.2021.104496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/25/2021] [Accepted: 09/01/2021] [Indexed: 12/29/2022]
Abstract
A tail of conspicuous coloration is hypothesized to be an advantageous trait for many species of lizards. Predator attacks would be directed to a non-vital, and autotomizable, body part, increasing the chance of survival. However, as body size increases it also increases the signaling area that could attract predators from greater distances, increasing the overall chance of predation. Here, we test the hypothesis that there is a trade-off between tail color and size, affecting predation probabilities. We used plasticine replicas of lizards to study the predation patterns of small and large lizards with red and blue tails. In a natural environment, we exposed six hundred replicas to the attacks of free-ranging predators. Large red-tailed replicas were more attacked by birds. Mammals and unidentified predators showed no preference for any size or colors. The attacks were not primarily directed to conspicuous tails when compared to the bodies/heads of our replicas. Our study suggests that red color signals in large lizards could enhance their detection by visually oriented predators (i.e., birds). The efficacy of conspicuous tails as a decoy may rely on associated behavioral displays, which are hard to test with static replicas.
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Affiliation(s)
- Raiane Dos Santos Guidi
- Laboratory of Sensory Ecology, Department of Physiology & Behavior, Federal University of Rio Grande do Norte, Natal, RN, Brazil
| | - Vinicius de Avelar São-Pedro
- Laboratory of Sensory Ecology, Department of Physiology & Behavior, Federal University of Rio Grande do Norte, Natal, RN, Brazil; Center of Natural Sciences, Federal University of São Carlos -Campus Lagoa do Sino, Buri, SP, Brazil
| | - Holda Ramos da Silva
- Laboratory of Sensory Ecology, Department of Physiology & Behavior, Federal University of Rio Grande do Norte, Natal, RN, Brazil
| | - Gabriel Correa Costa
- Department of Biology and Environmental Sciences, Auburn University at Montgomery, Montgomery, AL, USA
| | - Daniel Marques Almeida Pessoa
- Laboratory of Sensory Ecology, Department of Physiology & Behavior, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
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33
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Gomez D, Pinna C, Pairraire J, Arias M, Barbut J, Pomerantz A, Daney de Marcillac W, Berthier S, Patel N, Andraud C, Elias M. Wing transparency in butterflies and moths: structural diversity, optical properties, and ecological relevance. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Doris Gomez
- CEFE University of Montpellier CNRS, EPHE, IRD Montpellier France
| | - Charline Pinna
- ISYEB UMR 7205 CNRS, MNHN EPHE Sorbonne University Paris France
| | | | - Mónica Arias
- CEFE University of Montpellier CNRS, EPHE, IRD Montpellier France
- ISYEB UMR 7205 CNRS, MNHN EPHE Sorbonne University Paris France
| | - Jérôme Barbut
- ISYEB UMR 7205 CNRS, MNHN EPHE Sorbonne University Paris France
| | - Aaron Pomerantz
- Marine Biological Laboratory Woods Hole Massachusetts 02543 USA
- Department Integrative Biology University of California Berkeley Berkeley California 94720 USA
| | | | | | - Nipam Patel
- Marine Biological Laboratory Woods Hole Massachusetts 02543 USA
- University of Chicago Chicago Illinois 60607 USA
| | | | - Marianne Elias
- ISYEB UMR 7205 CNRS, MNHN EPHE Sorbonne University Paris France
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34
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Wang B, Yu L, Ma N, Zhang Z, Liu Q, Fan W, Rong Y, Zhang S, Li D. Discoid decorations function to shield juvenile Argiope spiders from avian predator attacks. Behav Ecol 2021. [DOI: 10.1093/beheco/arab089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Decorating behavior is common in various animal taxa and serves a variety of functions from camouflage to communication. One predominant function cited for decoration is to avoid predators. Conspicuous, disc-like (discoid) silk decorations spun by orb-web Argiope juvenile spiders are hypothesized, among others, to defend spiders against visual predators by concealing spider outlines on the web, deflecting attacks, shielding them from view, or masquerading as bird-droppings. However, the direct evidence is limited for a specific mechanism by which discoid decorations may deter predators. Here we evaluate the mechanisms by which discoid decorations may defend Argiope juveniles against naïve chicks. Using visual modeling, we show that avian predators are able to distinguish spiders from discoid decorations. Using chick predation experiments, we found that the naïve chicks readily pecked any objects, ruling out the possibility of their neophobia. Significantly more chicks attacked spiders when they were exposed to chicks, regardless of whether their webs had discoid decorations, but few chicks attacked spiders when they were behind the decorations. We also found that significantly few chicks attacked decorations when spiders were absent or behind the decorations. We thus conclude that discoid decorations function to deter avian predators by shielding the spider from view or distracting, not by deflecting attacks, concealing the spider’s outline, or masquerading as bird-droppings. This study sheds light on the study of other similar anti-predator strategies, in a wide range of spider species and other animals that use decorating strategies.
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Affiliation(s)
- Bingjun Wang
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Long Yu
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Nina Ma
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Zengtao Zhang
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Qian Liu
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Wenrui Fan
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Yu Rong
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Shichang Zhang
- Centre for Behavioural Ecology and Evolution, State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, China
| | - Daiqin Li
- Department of Biological Sciences, National University of Singapore, Singapore
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35
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Nahid MI, Fossøy F, Stokke BG, Abernathy V, Begum S, Langmore NE, Røskaft E, Ranke PS. No evidence of host-specific egg mimicry in Asian koels. PLoS One 2021; 16:e0253985. [PMID: 34242287 PMCID: PMC8270166 DOI: 10.1371/journal.pone.0253985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 06/16/2021] [Indexed: 11/19/2022] Open
Abstract
Avian brood parasitism is costly for the host, in many cases leading to the evolution of defenses like discrimination of parasitic eggs. The parasite, in turn, may evolve mimetic eggs as a counter-adaptation to host egg rejection. Some generalist parasites have evolved host-specific races (gentes) that may mimic the eggs of their main hosts, while others have evolved ‘jack-of-all-trades’ egg phenotypes that mimic key features of the eggs of several different host species. The Asian koel (Eudynamys scolopaceus) is a widely distributed generalist brood parasite that exploits a wide range of host species. Based on human vision, previous studies have described Asian koel eggs as resembling those of its main host, the house crow (Corvus splendens). Using measurements of egg length and breadth, digital image analysis, reflectance spectrophotometry and avian visual modelling, we examined Asian koel egg variation and potential mimicry in egg size and shape, and eggshell pattern and color in three sympatrically occurring host species in Bangladesh: the common myna (Acridotheres tristis), house crow, and long-tailed shrike (Lanius schach). We found some differences among Asian koel eggs laid in different host nests: a) Asian koel eggs in long-tailed shrike nests were larger than those laid in common myna and house crow nests, and b) Asian koel eggs in house crow nests were less elongated than those in common myna nests. However, these changes in Asian koel egg volume and shape were in the opposite direction with respect to their corresponding host egg characteristics. Thus, our study found no evidence for Asian koel host-specific egg mimicry in three sympatrically occurring host species.
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Affiliation(s)
- Mominul Islam Nahid
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Jahangirnagar University, Savar, Dhaka, Bangladesh
- * E-mail:
| | - Frode Fossøy
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway
| | - Bård G. Stokke
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway
| | - Virginia Abernathy
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Sajeda Begum
- Jahangirnagar University, Savar, Dhaka, Bangladesh
| | - Naomi E. Langmore
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Eivin Røskaft
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Peter S. Ranke
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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36
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Briolat ES, Gaston KJ, Bennie J, Rosenfeld EJ, Troscianko J. Artificial nighttime lighting impacts visual ecology links between flowers, pollinators and predators. Nat Commun 2021; 12:4163. [PMID: 34230463 PMCID: PMC8260664 DOI: 10.1038/s41467-021-24394-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 06/15/2021] [Indexed: 11/18/2022] Open
Abstract
The nighttime environment is being altered rapidly over large areas worldwide through introduction of artificial lighting, from streetlights and other sources. This is predicted to impact the visual ecology of many organisms, affecting both their intra- and interspecific interactions. Here, we show the effects of different artificial light sources on multiple aspects of hawkmoth visual ecology, including their perception of floral signals for pollination, the potential for intraspecific sexual signalling, and the effectiveness of their visual defences against avian predators. Light sources fall into three broad categories: some that prevent use of chromatic signals for these behaviours, others that more closely mimic natural lighting conditions, and, finally, types whose effects vary with light intensity and signal colour. We find that Phosphor Converted (PC) amber LED lighting – often suggested to be less harmful to nocturnal insects – falls into this third disruptive group, with unpredictable consequences for insect visual ecology depending on distance from the light source and the colour of the objects viewed. The diversity of impacts of artificial lighting on hawkmoth visual ecology alone argues for a nuanced approach to outdoor lighting in environmentally sensitive areas, employing intensities and spectra designed to limit those effects of most significant concern. Artificial light at night is a major way in which humans are altering the environment, impacting the ecology and behaviour of other species. Modelling how nocturnal hawkmoths see and are seen under multiple light sources suggests a range of potentially disruptive impacts on key behaviours.
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Affiliation(s)
| | - Kevin J Gaston
- Environment & Sustainability Institute, University of Exeter, Penryn, UK
| | - Jonathan Bennie
- Environment & Sustainability Institute, University of Exeter, Penryn, UK
| | - Emma J Rosenfeld
- Environment & Sustainability Institute, University of Exeter, Penryn, UK
| | - Jolyon Troscianko
- Centre for Ecology & Conservation, University of Exeter, Penryn, UK.
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37
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Caves EM, Dixit T, Colebrook-Robjent JFR, Hamusikili L, Stevens M, Thorogood R, Spottiswoode CN. Hosts elevate either within-clutch consistency or between-clutch distinctiveness of egg phenotypes in defence against brood parasites. Proc Biol Sci 2021; 288:20210326. [PMID: 34157874 PMCID: PMC8220279 DOI: 10.1098/rspb.2021.0326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In host-parasite arms races, hosts can evolve signatures of identity to enhance the detection of parasite mimics. In theory, signatures are most effective when within-individual variation is low ('consistency'), and between-individual variation is high ('distinctiveness'). However, empirical support for positive covariation in signature consistency and distinctiveness across species is mixed. Here, we attempt to resolve this puzzle by partitioning distinctiveness according to how it is achieved: (i) greater variation within each trait, contributing to elevated 'absolute distinctiveness' or (ii) combining phenotypic traits in unpredictable combinations ('combinatorial distinctiveness'). We tested how consistency covaries with each type of distinctiveness by measuring variation in egg colour and pattern in two African bird families (Cisticolidae and Ploceidae) that experience mimetic brood parasitism. Contrary to predictions, parasitized species, but not unparasitized species, exhibited a negative relationship between consistency and combinatorial distinctiveness. Moreover, regardless of parasitism status, consistency was negatively correlated with absolute distinctiveness across species. Together, these results suggest that (i) selection from parasites acts on how traits combine rather than absolute variation in traits, (ii) consistency and distinctiveness are alternative rather than complementary elements of signatures and (iii) mechanistic constraints may explain the negative relationship between consistency and absolute distinctiveness across species.
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Affiliation(s)
- Eleanor M Caves
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn TR10 9FE, UK
| | - Tanmay Dixit
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | | | | | - Martin Stevens
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn TR10 9FE, UK
| | - Rose Thorogood
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,HiLIFE Helsinki Institute of Life Sciences, University of Helsinki, Helsinki FI-00011, Finland.,Research Programme in Organismal and Evolutionary Biology, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki FI-00011, Finland
| | - Claire N Spottiswoode
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch 7701, South Africa
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38
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Pinzon-Rodriguez A, Muheim R. Cryptochrome expression in avian UV cones: revisiting the role of CRY1 as magnetoreceptor. Sci Rep 2021; 11:12683. [PMID: 34135416 PMCID: PMC8209128 DOI: 10.1038/s41598-021-92056-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 06/03/2021] [Indexed: 02/05/2023] Open
Abstract
Cryptochromes (CRY) have been proposed as putative magnetoreceptors in vertebrates. Localisation of CRY1 in the UV cones in the retinas of birds suggested that it could be the candidate magnetoreceptor. However, recent findings argue against this possibility. CRY1 is a type II cryptochrome, a subtype of cryptochromes that may not be inherently photosensitive, and it exhibits a clear circadian expression in the retinas of birds. Here, we reassessed the localisation and distribution of CRY1 in the retina of the zebra finch. Zebra finches have a light-dependent magnetic compass based on a radical-pair mechanism, similar to migratory birds. We found that CRY1 colocalised with the UV/V opsin (SWS1) in the outer segments of UV cones, but restricted to the tip of the segments. CRY1 was found in all UV cones across the entire retina, with the highest densities near the fovea. Pre-exposure of birds to different wavelengths of light did not result in any difference in CRY1 detection, suggesting that CRY1 did not undergo any detectable functional changes as result of light activation. Considering that CRY1 is likely not involved in magnetoreception, our findings open the possibility for an involvement in different, yet undetermined functions in the avian UV/V cones.
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Affiliation(s)
- Atticus Pinzon-Rodriguez
- grid.4514.40000 0001 0930 2361Department of Biology, Lund University, Biology Building B, 223 62 Lund, Sweden
| | - Rachel Muheim
- grid.4514.40000 0001 0930 2361Department of Biology, Lund University, Biology Building B, 223 62 Lund, Sweden
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39
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Ausprey IJ. Adaptations to light contribute to the ecological niches and evolution of the terrestrial avifauna. Proc Biol Sci 2021; 288:20210853. [PMID: 33975477 PMCID: PMC8113912 DOI: 10.1098/rspb.2021.0853] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The role of light in structuring the ecological niche remains a frontier in understanding how vertebrate communities assemble and respond to global change. For birds, eyes represent the primary external anatomical structure specifically evolved to interpret light, yet eye morphology remains understudied compared to movement and dietary traits. Here, I use Stanley Ritland's unpublished measurements of transverse eye diameter from preserved specimens to explore the ecological and phylogenetic drivers of eye morphology for a third of terrestrial avian diversity (N = 2777 species). Species with larger eyes specialized in darker understory and forested habitats, foraging manoeuvres and prey items requiring long-distance optical resolution and were more likely to occur in tropical latitudes. When compared to dietary and movement traits, eye size was a top predictor for habitat, foraging manoeuvre, diet and latitude, adding 8-28% more explanatory power. Eye size was phylogenetically conserved (λ = 0.90), with phylogeny explaining 61% of eye size variation. I suggest that light has contributed to the evolution and assembly of global vertebrate communities and that eye size provides a useful predictor to assess community response to global change.
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Affiliation(s)
- Ian J Ausprey
- Department of Biology and Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
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40
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Páez E, Valkonen JK, Willmott KR, Matos-Maraví P, Elias M, Mappes J. Hard to catch: experimental evidence supports evasive mimicry. Proc Biol Sci 2021; 288:20203052. [PMID: 33715434 DOI: 10.1098/rspb.2020.3052] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Most research on aposematism has focused on chemically defended prey, but the signalling difficulty of capture remains poorly explored. Similar to classical Batesian and Müllerian mimicry related to distastefulness, such 'evasive aposematism' may also lead to convergence in warning colours, known as evasive mimicry. A prime candidate group for evasive mimicry are Adelpha butterflies, which are agile insects and show remarkable colour pattern convergence. We tested the ability of naive blue tits to learn to avoid and generalize Adelpha wing patterns associated with the difficulty of capture and compared their response to that of birds that learned to associate the same wing patterns with distastefulness. Birds learned to avoid all wing patterns tested and generalized their aversion to other prey to some extent, but learning was faster with evasive prey compared to distasteful prey. Our results on generalization agree with longstanding observations of striking convergence in wing colour patterns among Adelpha species, since, in our experiments, perfect mimics of evasive and distasteful models were always protected during generalization and suffered the lowest attack rate. Moreover, generalization on evasive prey was broader compared to that on distasteful prey. Our results suggest that being hard to catch may deter predators at least as effectively as distastefulness. This study provides empirical evidence for evasive mimicry, a potentially widespread but poorly understood form of morphological convergence driven by predator selection.
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Affiliation(s)
- Erika Páez
- Institut de Systématique, Evolution, Biodiversité, Museum National d'Histoire Naturelle, CNRS, SU, EPHE, UA, Paris, France
| | - Janne K Valkonen
- Department of Biological and Environmental Science, University of Jyväskylä, Finland
| | - Keith R Willmott
- McGuire Center for Lepidoptera and Biodiversity, Florida Museum of Natural History, University of Florida, Gainesville, USA
| | - Pável Matos-Maraví
- Biology Centre CAS, Institute of Entomology, Branišovská 31, České Budějovice, Czech Republic
| | - Marianne Elias
- Institut de Systématique, Evolution, Biodiversité, Museum National d'Histoire Naturelle, CNRS, SU, EPHE, UA, Paris, France
| | - Johanna Mappes
- Department of Biological and Environmental Science, University of Jyväskylä, Finland.,Organismal and Evolutionary Biology Research Program Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
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41
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Detectability is in the eye of the beholder—the role of UV reflectance on tadpole detection and predation by a passerine bird. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-02983-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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42
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Silvasti SA, Valkonen JK, Nokelainen O. Behavioural thresholds of blue tit colour vision and the effect of background chromatic complexity. Vision Res 2021; 182:46-57. [PMID: 33596523 DOI: 10.1016/j.visres.2020.11.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 10/23/2020] [Accepted: 11/04/2020] [Indexed: 01/09/2023]
Abstract
Vision is a vital attribute to foraging, navigation, mate selection and social signalling in animals, which often have a very different colour perception in comparison to humans. For understanding how animal colour perception works, vision models provide the smallest colour difference that animals of a given species are assumed to detect. To determine the just-noticeable-difference, or JND, vision models use Weber fractions that set discrimination thresholds of a stimulus compared to its background. However, although vision models are widely used, they rely on assumptions of Weber fractions since the exact fractions are unknown for most species. Here, we test; i) which Weber fractions in long-, middle- and shortwave (i.e. L, M, S) colour channels best describe the blue tit (Cyanistes caeruleus) colour discrimination, ii) how changes in hue of saturated colours and iii) chromatic background noise impair search behaviour in blue tits. We show that the behaviourally verified Weber fractions on achromatic backgrounds were L: 0.05, M: 0.03 and S: 0.03, indicating a high colour sensitivity. In contrast, on saturated chromatic backgrounds, the correct Weber fractions were considerably higher for L: 0.20, M: 0.17 and S: 0.15, indicating a less detailed colour perception. Chromatic complexity of backgrounds affected the longwave channel, while middle- and shortwave channels were mostly unaffected. We caution that using a vision model whereby colour discrimination is determined in achromatic viewing conditions, as they often are, can lead to misleading interpretations of biological interactions in natural - colourful - environments.
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Affiliation(s)
- Sanni A Silvasti
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland.
| | - Janne K Valkonen
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Ossi Nokelainen
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
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43
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Yamamoto N, Sota T. Evolutionary fine-tuning of background-matching camouflage among geographical populations in the sandy beach tiger beetle. Proc Biol Sci 2020; 287:20202315. [PMID: 33323087 PMCID: PMC7779511 DOI: 10.1098/rspb.2020.2315] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/20/2020] [Indexed: 11/12/2022] Open
Abstract
Background-matching camouflage is a widespread adaptation in animals; however, few studies have thoroughly examined its evolutionary process and consequences. The tiger beetle Chaetodera laetescripta exhibits pronounced variation in elytral colour pattern among sandy habitats of different colour in the Japanese Archipelago. In this study, we performed digital image analysis with avian vision modelling to demonstrate that elytral luminance, which is attributed to proportions of elytral colour components, is fine-tuned to match local backgrounds. Field predation experiments with model beetles showed that better luminance matching resulted in a lower attack rate and corresponding lower mortality. Using restriction site-associated DNA (RAD) sequence data, we analysed the dispersal and evolution of colour pattern across geographical locations. We found that sand colour matching occurred irrespective of genetic and geographical distances between populations, suggesting that locally adapted colour patterns evolved after the colonization of these habitats. Given that beetle elytral colour patterns presumably have a quantitative genetic basis, our findings demonstrate that fine-tuning of background-matching camouflage to local habitat conditions can be attained through selection by visual predators, as predicted by the earliest proponent of natural selection.
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Affiliation(s)
- Nayuta Yamamoto
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Teiji Sota
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
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44
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Yeager J, Barnett JB. Ultraviolet components offer minimal contrast enhancement to an aposematic signal. Ecol Evol 2020; 10:13576-13582. [PMID: 33391663 PMCID: PMC7771128 DOI: 10.1002/ece3.6969] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/23/2020] [Accepted: 09/28/2020] [Indexed: 12/03/2022] Open
Abstract
Aposematic and sexual signals are often characterized by bright, highly contrasting colors. Many species can see colors beyond the human visible spectrum, and ultraviolet (UV) reflection has been found to play an important role in communication and sexual selection. However, the role of UV in aposematic signals is poorly explored. Poison frogs frequently produce high-contrast signals that have been linked to both aposematism and intraspecific communication. Yet despite considerable efforts studying interspecific and intraspecific diversity in color, poison frogs are not known to perceive UV, and UV reflection of the integument has not been described. We report UV-reflective spots in a population of Oophaga sylvatica and quantify the effect of UV on visual contrast with models of avian vision. We found that the frogs are highly contrasting, but UV had a minimal effect on signal saliency. These data highlight the importance of considering UV reflectance within aposematic signals, but that UV should not necessarily be regarded as an independent signal.
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Affiliation(s)
- Justin Yeager
- Biodiversidad Medio Ambiente y SaludUniversidad de Las AméricasQuitoEcuador
| | - James B. Barnett
- Department of Psychology, Neuroscience & BehaviourMcMaster UniversityHamiltonONCanada
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45
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Luro AB, Fernández-Juricic E, Baumhardt P, Hauber ME. Visual acuity and egg spatial chromatic contrast predict egg rejection behavior of American robins. J Exp Biol 2020; 223:jeb229609. [PMID: 32895322 DOI: 10.1242/jeb.229609] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 08/29/2020] [Indexed: 08/25/2023]
Abstract
Color and spatial vision is critical for recognition and discrimination tasks affecting fitness, including finding food and mates, and recognizing offspring. For example, as a counter defense to avoid the cost of raising the unrelated offspring of obligate interspecific avian brood parasites, many host species routinely view, recognize and remove the foreign egg(s) from their nests. Recent research has shown that host species visually attend to both chromatic and spatial pattern features of eggs; yet how hosts simultaneously integrate these features together when recognizing eggs remains an open question. Here, we tested egg rejection responses of American robins (Turdus migratorius) using a range of 3D-printed model eggs covered with blue and yellow checkered patterns differing in relative square sizes. We predicted that robins would reject a model egg if they could visually resolve the blue and yellow squares as separate features, or accept it if the squares blended together and appeared similar in color to the natural blue-green color of robin eggs as perceived by the avian visual system. As predicted, the probability of robins rejecting a model egg increased with greater sizes of its blue and yellow squares. Our results suggest that chromatic visual acuity and viewing distance have the potential to limit the ability of a bird to recognize a foreign egg in its nest, thus providing a limitation to host egg recognition that obligate interspecific avian brood parasites may exploit.
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Affiliation(s)
- Alec B Luro
- Department of Evolution, Ecology and Behavior, School of Integrative Biology, University of Illinois, Urbana-Champaign, IL 61801, USA
| | - Esteban Fernández-Juricic
- Department of Biological Sciences, College of Science, Purdue University, West Lafayette, IN 47907, USA
| | - Patrice Baumhardt
- Department of Biological Sciences, College of Science, Purdue University, West Lafayette, IN 47907, USA
| | - Mark E Hauber
- Department of Evolution, Ecology and Behavior, School of Integrative Biology, University of Illinois, Urbana-Champaign, IL 61801, USA
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46
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Chen Z, Niu Y, Liu CQ, Sun H. Red flowers differ in shades between pollination systems and across continents. ANNALS OF BOTANY 2020; 126:837-848. [PMID: 32478385 PMCID: PMC7539362 DOI: 10.1093/aob/mcaa103] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 05/26/2020] [Indexed: 05/14/2023]
Abstract
BACKGROUND AND AIMS Floral colour is a primary signal in plant-pollinator interactions. The association between red flowers and bird pollination is well known, explained by the 'bee avoidance' and 'bird attraction' hypotheses. Nevertheless, the relative importance of these two hypotheses has rarely been investigated on a large scale, even in terms of colour perception per se. METHODS We collected reflectance spectra for 130 red flower species from different continents and ascertained their pollination systems. The spectra were analysed using colour vision models for bees and (three types of) birds, to estimate colour perception by these pollinators. The differences in colour conspicuousness (chromatic and achromatic contrast, purity) and in spectral properties between pollination systems and across continents were analysed. KEY RESULTS Compared with other floral colours, red flowers are very conspicuous to birds and much less conspicuous to bees. The red flowers pollinated by bees and by birds are more conspicuous to their respective pollinators. Compared with the bird flowers in the Old World, the New World ones are less conspicuous to bees and may be more conspicuous not only to violet-sensitive but also to ultraviolet-sensitive birds. These differences can be explained by the different properties of the secondary reflectance peak (SP). SP intensity is higher in red flowers pollinated by bees than those pollinated by birds (especially New World bird flowers). A transition from high SP to low SP in red flowers can induce chromatic contrast changes, with a greater effect on reducing attraction to bees than enhancing attraction to birds. CONCLUSIONS Shades of red flowers differ between pollination systems. Moreover, red bird flowers are more specialized in the New World than in the Old World. The evolution towards colour specialization is more likely to result in higher efficiency of bee avoidance than bird attraction.
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Affiliation(s)
- Zhe Chen
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yang Niu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Chang-Qiu Liu
- Center for Gardens and Horticultural Studies, Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin, Guangxi, China
| | - Hang Sun
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
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47
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Wilts BD. Fruit Coloration: Attractive, Fatty Blue Colours? Curr Biol 2020; 30:R1078-R1080. [PMID: 33022238 DOI: 10.1016/j.cub.2020.07.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The use of visible colours as honest signals to attract seed-dispersers is a well-known property of fruits. While most of these colours are due to pigments, it has now been discovered that the evergreen Viburnum tinus shrubs display their edible and nutritious fruit with a blue structural colour based on lipid inclusions in the epidermal cells.
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Affiliation(s)
- Bodo D Wilts
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland.
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48
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Krishnan A, Singh A, Tamma K. Visual signal evolution along complementary color axes in four bird lineages. Biol Open 2020; 9:bio052316. [PMID: 32878876 PMCID: PMC7520455 DOI: 10.1242/bio.052316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 08/17/2020] [Indexed: 11/20/2022] Open
Abstract
Avian color patterns function in varied behavioral contexts, most being produced by only a handful of mechanisms including feather nanostructures and pigments. Within a clade, colors may not occupy the entire available space, and incorporating complementary colors may increase the contrast and efficacy of visual signals. Here, we describe plumage patterns in four ecologically and phylogenetically diverse bird families to test whether they possess complementary colors. We present evidence that plumage colors in each clade cluster along a line in tetrachromatic color space. Additionally, we present evidence that in three of these clades, this line contains colors on opposite sides of a line passing through the achromatic point (putatively complementary colors, presenting higher chromatic contrast). Finally, interspecific color variation over at least some regions of the body is not constrained by phylogenetic relatedness. By describing plumage patterns in four diverse lineages, we add to the growing body of literature suggesting that the diversity of bird visual signals is constrained. Further, we tentatively hypothesize that in at least some clades possessing bright colors, species-specific plumage patterns may evolve by swapping the distributions of a complementary color pair. Further research on other bird clades may help confirm whether these patterns are general across bird families.
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Affiliation(s)
- Anand Krishnan
- Department of Biology, Indian Institute of Science Education and Research, Pashan Road, Pune 411008, India
| | | | - Krishnapriya Tamma
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru 560012, India
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49
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Ma N, Yu L, Gong D, Hua Z, Zeng H, Chen L, Mao A, Chen Z, Cai R, Ma Y, Zhang Z, Li D, Luo J, Zhang S. Detritus decorations as the extended phenotype deflect avian predator attack in an orb‐web spider. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13636] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Nina Ma
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Long Yu
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Deyong Gong
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Zeyuan Hua
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Hua Zeng
- State Key Laboratory of Protein and Plant Gene Research Peking‐Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary Studies Peking University Beijing China
| | - Luyao Chen
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Aijia Mao
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Zhizhao Chen
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Ruxing Cai
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Yubing Ma
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Zengtao Zhang
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Daiqin Li
- Department of Biological Sciences National University of Singapore Singapore Singapore
| | - Jing Luo
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
| | - Shichang Zhang
- Centre for Behavioral Ecology and Evolution State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life Sciences Hubei University Wuhan China
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50
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Jamie GA, Van Belleghem SM, Hogan BG, Hamama S, Moya C, Troscianko J, Stoddard MC, Kilner RM, Spottiswoode CN. Multimodal mimicry of hosts in a radiation of parasitic finches. Evolution 2020; 74:2526-2538. [PMID: 32696463 DOI: 10.1111/evo.14057] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 06/27/2020] [Accepted: 07/02/2020] [Indexed: 01/16/2023]
Abstract
Brood parasites use the parental care of others to raise their young and sometimes employ mimicry to dupe their hosts. The brood-parasitic finches of the genus Vidua are a textbook example of the role of imprinting in sympatric speciation. Sympatric speciation is thought to occur in Vidua because their mating traits and host preferences are strongly influenced by their early host environment. However, this alone may not be sufficient to isolate parasite lineages, and divergent ecological adaptations may also be required to prevent hybridization collapsing incipient species. Using pattern recognition software and classification models, we provide quantitative evidence that Vidua exhibit specialist mimicry of their grassfinch hosts, matching the patterns, colors and sounds of their respective host's nestlings. We also provide qualitative evidence of mimicry in postural components of Vidua begging. Quantitative comparisons reveal small discrepancies between parasite and host phenotypes, with parasites sometimes exaggerating their host's traits. Our results support the hypothesis that behavioral imprinting on hosts has not only enabled the origin of new Vidua species, but also set the stage for the evolution of host-specific, ecological adaptations.
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Affiliation(s)
- Gabriel A Jamie
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Steven M Van Belleghem
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,Department of Biology, University of Puerto Rico-Rio Piedras, San Juan, Puerto Rico
| | - Benedict G Hogan
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey
| | | | | | - Jolyon Troscianko
- Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall, United Kingdom
| | - Mary Caswell Stoddard
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey
| | - Rebecca M Kilner
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Claire N Spottiswoode
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, Cape Town, South Africa
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