1
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John L, Santon M, Michiels NK. Scorpionfish adjust skin pattern contrast on different backgrounds. Ecol Evol 2024; 14:e11124. [PMID: 38476704 PMCID: PMC10928359 DOI: 10.1002/ece3.11124] [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: 11/15/2023] [Revised: 02/06/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
The two scorpionfish species Scorpaena maderensis and S. porcus are well camouflaged ambush predators that rapidly change body colouration to adjust to background colour in less than 1 min. We tested whether individuals of both species also adjust body pattern to that of the background. We placed fish on backgrounds of different pattern granularity and quantified the change in fish body pattern over 1 min. We used calibrated image analysis to analyse the patterns from the visual perspective of a prey fish species using a granularity (pattern energy) analysis and an image clustering approach. In our experiment, fish did not change their most contrasting pattern components as defined by the dominant marking size, but changed their average marking size. Moreover, fish responded with a change in pattern in contrast to the different experimental backgrounds, especially when compared to the acclimation phase. These results indicate that scorpionfish have one main pattern that can be adjusted by modulating its internal contrast. A reduction in pattern contrast could thereby improve background matching, while an increase could promote camouflage via disruptive colouration.
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Affiliation(s)
- Leonie John
- Animal Evolutionary EcologyInstitute of Evolution and Ecology, University of TübingenTübingenGermany
| | - Matteo Santon
- Ecology of Vision Group, School of Biological SciencesUniversity of BristolBristolUK
| | - Nico K. Michiels
- Animal Evolutionary EcologyInstitute of Evolution and Ecology, University of TübingenTübingenGermany
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2
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Dobson JL, Pike TW, Gonzalez-Rodriguez J, Soulsbury CD. Identifying and locating carotenoids in supra-orbital combs of male black grouse (Lyurus tetrix) using Raman and transmission electron microscopy: A histological study using rehydrated tissue samples. J Morphol 2023; 284:e21652. [PMID: 37990765 DOI: 10.1002/jmor.21652] [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: 02/21/2023] [Revised: 09/28/2023] [Accepted: 10/02/2023] [Indexed: 11/23/2023]
Abstract
Colourful signals have long been implicated as indicators of individual quality in animals. Bare-skin signals are an understudied aspect of avian colouration compared with plumage studies, despite displaying rapid changes in size and colour in response to different environmental or physiological stressors. Even fewer studies have focused on the underlying histology of these structures and the importance this plays in the resulting skin colour. Using the Black Grouse (Lyrurus tetrix), we identified the underlying structure of individual dermal spikes, which make up the red supra-orbital comb (a known integumentary signal of male quality), and highlight visual structural differences between combs of different sizes. In addition, we used Raman spectroscopy to indicate the presence of carotenoids within the tissue, something that had previously only been inferred through characteristic reflectance patterns. An increased understanding of the structural basis of colour of featherless parts of the skin opens up exciting new avenues for interpreting the information content of integumentary signals.
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Affiliation(s)
- Jessica L Dobson
- Department of Life Sciences, School of Life and Environmental Sciences, University of Lincoln, Lincoln, Brayford Pool, UK
| | - Thomas W Pike
- Department of Life Sciences, School of Life and Environmental Sciences, University of Lincoln, Lincoln, Brayford Pool, UK
| | - Jose Gonzalez-Rodriguez
- Joseph Banks Laboratories, School of Chemistry, University of Lincoln, Lincoln, Brayford Pool, UK
| | - Carl D Soulsbury
- Department of Life Sciences, School of Life and Environmental Sciences, University of Lincoln, Lincoln, Brayford Pool, UK
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3
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Moyaho A, Salazar-Bautista JL, Beristain-Castillo E, Amira FU. Iridescent scales signal male fighting ability to access females in the jewelled splitfin Xenotoca variata. JOURNAL OF FISH BIOLOGY 2023; 102:794-802. [PMID: 36648014 DOI: 10.1111/jfb.15316] [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: 06/29/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
Jewelled splitfin males (Xenotoca variata) possess multi-colour iridescent scales (speckles) on the flanks. This study tested the hypothesis that the number of speckles could be a good proxy for predicting fighting ability in contests for access to females. The experiments consisted in observing and recording males' agonistic behaviour, courtship displays and mating attempts in mixed-sex groups. The data were analysed and presented based on a Bayesian approach, which revealed that the density (cm-2 ) of speckles was positively correlated with the increase observed in the proportional frequency of attacks. Similarly, the density of speckles was positively associated with the increase observed in the frequency of courtship behaviour and with the frequency of mating attempts. Male-male aggressions drastically diminished (by eightfold) when females were removed from the observation tanks. These results indicate that the number of speckles is a consistent predictor of successful access to females and therefore, speckled males are likely to be able to gain more mating opportunities. This finding highlights the ubiquitous role iridescent colours play in visual signalling.
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Affiliation(s)
- Alejandro Moyaho
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, Puebla, Mexico
| | - José Luis Salazar-Bautista
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, Puebla, Mexico
| | | | - Flores-Urbina Amira
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, Puebla, Mexico
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4
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Penteriani V, Hartasánchez A, García JD, Magadan Ruitiña JR, Mar Delgado MD. Brown bear body patches are temporally stable and represent a unique individual visual signature. URSUS 2023. [DOI: 10.2192/ursus-d-22-00015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Vincenzo Penteriani
- National Museum of Natural Sciences (MNCN), Department of Evolutionary Ecology, Spanish National Research Council (CSIC), c/José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Alfonso Hartasánchez
- FAPAS Fondo para la Protección de los Animales Salvajes, Ctra. AS-228, km 8.9 – Tuñón, 33115 Santo Adriano, Asturias, Spain
| | - Juan Díaz García
- Consejería de Ordenación del Territorio, Infraestructuras y Medio Ambiente, Dirección General de Biodiversidad, Principado de Asturias, 33000 Oviedo, Spain
| | - José Ramón Magadan Ruitiña
- FAPAS Fondo para la Protección de los Animales Salvajes, Ctra. AS-228, km 8.9 – Tuñón, 33115 Santo Adriano, Asturias, Spain
| | - María del Mar Delgado
- Biodiversity Research Institute (IMIB, CSIC-UO-PA), Mieres Campus, 33600 Mieres, Spain
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5
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Discriminant Criteria for Field Sexing in the Eurasian Tree Sparrow by Combining Body Size and Plumage Features. BIRDS 2022. [DOI: 10.3390/birds3040027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
The Eurasian tree sparrow (Passer montanus) is a monomorphic passerine, for which it is impossible to differentiate between males and females based on external characteristics. Being a species frequently captured for ringing, having a reliable method to determine sex from conventional biometric measurements would facilitate its study and be very useful for the correct management and conservation of this declining species. In the present study, we used biometric measurements recorded in 66 individuals captured with mist nets in communal roosts in northern Spain during the winter and sexed them using molecular techniques. We conducted a discriminant function analysis (DFA) to derive equations that allowed us to determine the sex of the specimens from some of the measurements recorded in the field. Significant differences were found between males and females in wing length, third primary length, badge width and height and body weight. The DFA provided two functions that correctly classified the sex of 94.7% of the individuals using wing length and badge width, and 98.2% if weight was added to the analysis. Our results allow sexing from measurements that can be easily recorded in the field with the tools commonly used in banding sessions and without the need for additional training. Considerations of Bergmann’s and Allen’s rules on body size and the use of DFA in different populations are discussed.
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6
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Morandi K, Lindholm AK, Lee DE, Bond ML. Phenotypic matching by spot pattern potentially mediates female giraffe social associations. J Zool (1987) 2022. [DOI: 10.1111/jzo.13009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Morandi
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| | - A. K. Lindholm
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| | - D. E. Lee
- Wild Nature Institute Concord NH USA
- Department of Biology Pennsylvania State University University Park PA USA
| | - M. L. Bond
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
- Wild Nature Institute Concord NH USA
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7
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Hegyi G, Laczi M, Herényi M, Markó G, Nagy G, Rosivall B, Szász E, Török J. Functional integration of multiple sexual ornaments: signal coherence and sexual selection. Am Nat 2022; 200:486-505. [DOI: 10.1086/720620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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8
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Hulse SV, Renoult JP, Mendelson TC. Using deep neural networks to model similarity between visual patterns: Application to fish sexual signals. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2021.101486] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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9
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Goldenberg J, Bisschop K, D'Alba L, Shawkey MD. The link between body size, colouration and thermoregulation and their integration into ecogeographical rules: a critical appraisal in light of climate change. OIKOS 2022. [DOI: 10.1111/oik.09152] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Jonathan Goldenberg
- Evolution and Optics of Nanostructures group, Dept of Biology, Ghent Univ. Ghent Belgium
| | - Karen Bisschop
- Inst. for Biodiversity and Ecosystem Dynamics, Univ. of Amsterdam Amsterdam the Netherlands
- Laboratory of Aquatic Biology, Dept of Biology, KU Leuven KULAK Kortrijk Belgium
| | - Liliana D'Alba
- Evolution and Optics of Nanostructures group, Dept of Biology, Ghent Univ. Ghent Belgium
| | - Matthew D. Shawkey
- Evolution and Optics of Nanostructures group, Dept of Biology, Ghent Univ. Ghent Belgium
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10
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Fülöp A, Lukács D, Fábián PI, Kocsis B, Csöppü G, Bereczki J, Barta Z. Sex-specific signalling of individual personality by a mutual plumage ornament in a passerine. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-02971-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Abstract
The significance of colour signals in species with strong sexual dimorphism and/or elaborated visual ornaments is rather well-understood. Less attention has, however, been devoted to study colour signals in species with weak or no apparent sexual dimorphism. In such species, an interesting possibility arises as both sexes can bear the same colour ornament(s) (i.e. sexes are mutually ornamented), but their signalling value might differ in males and females. We aimed to explore this possibility by investigating the phenotypic correlates of the black bib, a melanin-based plumage ornament, in the Eurasian tree sparrow (Passer montanus). More specifically, we studied the sex-dependent relationships between bib size and three aspects of individuals’ phenotype: body condition (i.e. size-corrected body mass), physiology (i.e. cellular innate immunity/inflammation status, expressed through total leucocyte counts, and chronic physiological stress, expressed through the ratio of heterophils to lymphocytes) and individual personality (i.e. activity in a novel environment). We found that bib size was not associated with body condition and cellular innate immunity/inflammation status, but was positively related to physiological stress levels independent of sex. Furthermore, bib size was negatively associated with activity in males but positively in females. Our findings bring important correlative evidence that mutual ornamental traits may have sex-specific signalling value.
Significance statement
The signalling role of elaborated colourful ornaments, that are usually possessed only by males in sexually dimorphic species, is well-established. The function of various colour traits which are borne by both sexes (i.e. mutual ornaments), however, is less obvious. Do they have a signalling value in both sexes? If yes, do they signal the same information in males and females? Or, most intriguingly, can they convey different information in the two sexes? To test these alternatives, we studied the signalling value of the black bib, a melanin-based mutual plumage ornament, in Eurasian tree sparrows (Passer montanus). Apart from being correlated with chronic stress in both sexes, bib size was positively related to activity in females but negatively in males. Our results suggest that the information content of the same colour trait in males and females can be different in mutually ornamented species.
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11
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Penteriani V, Te WS, May CL, Wah SY, Crudge B, Broadis N, Bombieri G, Valderrábano E, Russo LF, Mar Delgado MD. Characteristics of sun bear chest marks and their patterns of individual variation. URSUS 2021. [DOI: 10.2192/ursus-d-19-00027.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Vincenzo Penteriani
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, 33600 Mieres, Spain
| | - Wong Siew Te
- Bornean Sun Bear Conservation Centre, PPM 219, Elopura, 90000 Sandakan, Sabah, Malaysia (https://www.bsbcc.org.my/)
| | - Chiew Lin May
- Bornean Sun Bear Conservation Centre, PPM 219, Elopura, 90000 Sandakan, Sabah, Malaysia (https://www.bsbcc.org.my/)
| | - Seng Yen Wah
- Bornean Sun Bear Conservation Centre, PPM 219, Elopura, 90000 Sandakan, Sabah, Malaysia (https://www.bsbcc.org.my/)
| | - Brian Crudge
- Free the Bears, P.O. Box 273, Phnom Penh, Cambodia (https://freethebears.org/)
| | - Nev Broadis
- Free the Bears, P.O. Box 273, Phnom Penh, Cambodia (https://freethebears.org/)
| | - Giulia Bombieri
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, 33600 Mieres, Spain
| | - Esther Valderrábano
- COPAR Research Group, Faculty of Veterinary, University of Santiago de Compostela, Avda. Carballo Calero s/n, 27002, Lugo, Spain
| | - Luca Francesco Russo
- Università degli Studi del Molise, Dipartimento Bioscienze e Territorio, Contrada Fonte Lappone, 86090 Pesche (IS), Italy
| | - María Del Mar Delgado
- Research Unit of Biodiversity (UMIB, CSIC-UO-PA), Mieres Campus, 33600 Mieres, Spain
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12
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Goldenberg J, D'Alba L, Bisschop K, Vanthournout B, Shawkey MD. Substrate thermal properties influence ventral brightness evolution in ectotherms. Commun Biol 2021; 4:26. [PMID: 33398079 PMCID: PMC7782800 DOI: 10.1038/s42003-020-01524-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 11/25/2020] [Indexed: 01/29/2023] Open
Abstract
The thermal environment can affect the evolution of morpho-behavioral adaptations of ectotherms. Heat is transferred from substrates to organisms by conduction and reflected radiation. Because brightness influences the degree of heat absorption, substrates could affect the evolution of integumentary optical properties. Here, we show that vipers (Squamata:Viperidae) inhabiting hot, highly radiative and superficially conductive substrates have evolved bright ventra for efficient heat transfer. We analyzed the brightness of 4161 publicly available images from 126 species, and we found that substrate type, alongside latitude and body mass, strongly influences ventral brightness. Substrate type also significantly affects dorsal brightness, but this is associated with different selective forces: activity-pattern and altitude. Ancestral estimation analysis suggests that the ancestral ventral condition was likely moderately bright and, following divergence events, some species convergently increased their brightness. Vipers diversified during the Miocene and the enhancement of ventral brightness may have facilitated the exploitation of arid grounds. We provide evidence that integument brightness can impact the behavioral ecology of ectotherms.
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Affiliation(s)
- Jonathan Goldenberg
- Evolution and Optics of Nanostructures group, Department of Biology, Ghent University, 9000, Ghent, Belgium.
| | - Liliana D'Alba
- Evolution and Optics of Nanostructures group, Department of Biology, Ghent University, 9000, Ghent, Belgium
| | - Karen Bisschop
- Terrestrial Ecology Unit, Department of Biology, Ghent University, 9000, Ghent, Belgium
- Theoretical Research in Evolutionary Life Sciences, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9700 CC, Groningen, The Netherlands
| | - Bram Vanthournout
- Evolution and Optics of Nanostructures group, Department of Biology, Ghent University, 9000, Ghent, Belgium
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures group, Department of Biology, Ghent University, 9000, Ghent, Belgium
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13
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Potash AD, Greene DU, Foursa GA, Mathis VL, Conner LM, McCleery RA. A comparison of animal color measurements using a commercially available digital color sensor and photograph analysis. Curr Zool 2020; 66:601-606. [PMID: 33391358 PMCID: PMC7769579 DOI: 10.1093/cz/zoaa016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 03/21/2020] [Indexed: 11/14/2022] Open
Abstract
An animal's pelage, feather, or skin color can serve a variety of functions, so it is important to have multiple standardized methods for measuring color. One of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of animals. New technology in the form of a commercially available handheld digital color sensor could provide an alternative to photography-based animal color measurements. To determine whether a digital color sensor could be used to measure animal coloration, we tested the ability of a digital color sensor to measure coloration of mammalian, avian, and lepidopteran museums specimens. We compared results from the sensor to measurements taken using traditional photography methods. Our study yielded significant differences between photography-based and digital color sensor measurements of brightness (light to dark) and colors along the green to red spectrum. There was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow spectrum. The average difference in recorded color (ΔE) by the 2 methods was above the threshold at which humans can perceive a difference. There were significant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring tool. However, the sensor's small aperture and narrow light spectrum range designed for human-vision limit its value for ecological research. We discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field.
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Affiliation(s)
- Alex D Potash
- Department of Wildlife Ecology and Conservation, University of Florida Institute of Food and Agricultural Science, Gainesville, FL 32611, USA
| | - Daniel U Greene
- Weyerhaeuser Company, Environmental Research South, Columbus, MS 39701, USA
| | - Gabrielle A Foursa
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Verity L Mathis
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | | | - Robert A McCleery
- Department of Wildlife Ecology and Conservation, University of Florida Institute of Food and Agricultural Science, Gainesville, FL 32611, USA
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14
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Hyeun-Ji L, Rendón MÁ, Liedtke HC, Gomez-Mestre I. Shifts in the developmental rate of spadefoot toad larvae cause decreased complexity of post-metamorphic pigmentation patterns. Sci Rep 2020; 10:19624. [PMID: 33184389 PMCID: PMC7665075 DOI: 10.1038/s41598-020-76578-1] [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: 07/28/2020] [Accepted: 10/27/2020] [Indexed: 11/18/2022] Open
Abstract
Amphibian larvae are plastic organisms that can adjust their growth and developmental rates to local environmental conditions. The consequences of such developmental alterations have been studied in detail, both at the phenotypic and physiological levels. While largely unknown, it is of great importance to assess how developmental alterations affect the pigmentation pattern of the resulting metamorphs, because pigmentation is relevant for communication, mate choice, and camouflage and hence influences the overall fitness of the toads. Here we quantify the variation in several aspects of the pigmentation pattern of juvenile spadefoot toads experimentally induced to accelerate their larval development in response to decreased water level. It is known that induced developmental acceleration comes at the cost of reduced size at metamorphosis, higher metabolic rate, and increased oxidative stress. In this study, we show that spadefoot toads undergoing developmental acceleration metamorphosed with a less complex, more homogeneous, darker dorsal pattern consisting of continuous blotches, compared to the more contrasted pattern with segregated blotches and higher fractal dimension in normally developing individuals, and at a smaller size. We also observed a marked effect of population of origin in the complexity of the pigmentation pattern. Complexity of the post-metamorphic dorsal pigmentation could therefore be linked to pre-metamorphic larval growth and development.
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Affiliation(s)
- Lee Hyeun-Ji
- Ecology, Evolution, and Development Group, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
| | - Miguel Ángel Rendón
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
| | - Hans Christoph Liedtke
- Ecology, Evolution, and Development Group, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
| | - Ivan Gomez-Mestre
- Ecology, Evolution, and Development Group, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain.
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain.
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15
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Badejo O, Skaldina O, Gilev A, Sorvari J. Benefits of insect colours: a review from social insect studies. Oecologia 2020; 194:27-40. [PMID: 32876763 PMCID: PMC7561587 DOI: 10.1007/s00442-020-04738-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 08/19/2020] [Indexed: 11/28/2022]
Abstract
Insect colours assist in body protection, signalling, and physiological adaptations. Colours also convey multiple channels of information. These channels are valuable for species identification, distinguishing individual quality, and revealing ecological or evolutionary aspects of animals' life. During recent years, the emerging interest in colour research has been raised in social hymenopterans such as ants, wasps, and bees. These insects provide important ecosystem services and many of those are model research organisms. Here we review benefits that various colour types give to social insects, summarize practical applications, and highlight further directions. Ants might use colours principally for camouflage, however the evolutionary function of colour in ants needs more attention; in case of melanin colouration there is evidence for its interrelation with thermoregulation and pathogen resistance. Colours in wasps and bees have confirmed linkages to thermoregulation, which is increasingly important in face of global climate change. Besides wasps use colours for various types of signalling. Colour variations of well chemically defended social insects are the mimetic model for unprotected organisms. Despite recent progress in molecular identification of species, colour variations are still widely in use for species identification. Therefore, further studies on variability is encouraged. Being closely interconnected with physiological and biochemical processes, insect colouration is a great source for finding new ecological indicators and biomarkers. Due to novel digital imaging techniques, software, and artificial intelligence there are emerging possibilities for new advances in this topic. Further colour research in social insects should consider specific features of sociality.
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Affiliation(s)
- Oluwatobi Badejo
- Department of Environmental and Biological Sciences, University of Eastern Finland, Yliopistonranta 1, P.O. Box 1627, 70211, Kuopio, Finland
| | - Oksana Skaldina
- Department of Environmental and Biological Sciences, University of Eastern Finland, Yliopistonranta 1, P.O. Box 1627, 70211, Kuopio, Finland.
| | - Aleksei Gilev
- Institute of Plant and Animal Ecology (IPAE), Ural Centre of the Russian Academy of Sciences, 8 Marta Street, 202, 620144, Yekaterinburg, Russia.,Institute of Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences, Ural Federal University, Mira Street, 19, 620002, Ekaterinburg, Russia
| | - Jouni Sorvari
- Department of Environmental and Biological Sciences, University of Eastern Finland, Yliopistonranta 1, P.O. Box 1627, 70211, Kuopio, Finland.,Department of Biology, University of Turku, 20014, Turku, Finland
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16
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Prinsloo ND, Postma M, de Bruyn PJN. How unique is unique? Quantifying geometric differences in stripe patterns of Cape mountain zebra, Equus zebra zebra (Perissodactyla: Equidae). Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlaa036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Quantified coat pattern dissimilarity provides a visible surface for individual animal traceability to populations. We determined the feasibility in quantifying uniqueness of stripe patterns of Cape mountain zebra (CMZ; Equus zebra zebra) using geometric morphometrics. We photogrammetrically created dense surface models of CMZ (N = 56). Stripe edges were landmarked, superimposed and compared for shape variation across replicates and the population. Significant allometry in stripe patterns prompted allometric correction to remove increased curvature of stripes at the rump, belly and back with larger adult individuals, to facilitate equilibrated comparison between individuals. Re-landmarked replicates showed lower dissimilarity (Di) than non-replicates (Dp), representing minimal landmarking error. Individuals were 78.07 ± 1.79% unique (U=1−DiDp×100%) relative to the study population. Size, the number of torso stripes and degree of branching in four rear torso stripes described the most shape variation (36.79%) but a significant portion could only be distinguished with geometric morphometrics (41.82%). This is the first known use of geometric morphometrics to quantify coat pattern uniqueness, using a model species to provide baseline individual morphological variation. Measures of coat pattern similarity have a place in phenotypic monitoring and identification.
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Affiliation(s)
- Nicolas D Prinsloo
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
| | - Martin Postma
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
| | - P J Nico de Bruyn
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
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17
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Stoddard MC, Hogan BG, Stevens M, Spottiswoode CN. Higher-level pattern features provide additional information to birds when recognizing and rejecting parasitic eggs. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180197. [PMID: 30967078 DOI: 10.1098/rstb.2018.0197] [Citation(s) in RCA: 12] [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
Despite a recent explosion of research on pattern recognition, in both neuroscience and computer vision, we lack a basic understanding of how most animals perceive and respond to patterns in the wild. Avian brood parasites and their hosts provide an ideal study system for investigating the mechanisms of pattern recognition. The cuckoo finch, Anomalospiza imberbis, and its host the tawny-flanked prinia, Prinia subflava, lay highly polymorphic eggs with a great deal of variation in colour and patterning, with the cuckoo finch capable of close egg mimicry. Behavioural experiments in Zambia have previously shown that prinias use colour and multiple 'low-level' (occurring in early stages of visual processing) pattern attributes, derived from spatial frequency analysis, when rejecting foreign eggs. Here, we explore the extent to which host birds might also use 'higher-level' pattern attributes, derived from a feature detection algorithm, to make rejection decisions. Using a SIFT-based pattern recognition algorithm, NaturePatternMatch, we show that hosts are more likely to reject a foreign egg if its higher-level pattern features-which capture information about the shape and orientation of markings-differ from those of the host eggs. A revised statistical model explains about 37% variance in egg rejection behaviour, and differences in colour, low-level and higher-level pattern features all predict rejection, accounting for 42, 44 and 14% of the explained variance, respectively. Thus, higher-level pattern features provide a small but measurable improvement to the original model and may be especially useful when colour and low-level pattern features provide hosts with little information. Understanding the relative importance of low- and higher-level pattern features is a valuable goal for future work on animal coloration, especially in the contexts of mimicry, camouflage and individual recognition. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.
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Affiliation(s)
- Mary Caswell Stoddard
- 1 Department of Ecology and Evolutionary Biology, Princeton University , Princeton, NJ 08544 , USA
| | - Benedict G Hogan
- 1 Department of Ecology and Evolutionary Biology, Princeton University , Princeton, NJ 08544 , USA
| | - Martin Stevens
- 2 Centre for Ecology and Conservation, University of Exeter , Penryn Campus, Penryn, Cornwall TR10 9FE , UK
| | - Claire N Spottiswoode
- 3 Department of Zoology, University of Cambridge , Cambridge CB2 3EJ , UK.,4 FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town , Rondebosch 7701, Cape Town , South Africa
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18
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Abstract
Abstract
Lures are deceptive strategies that exploit sensory biases in prey, usually mimicking a prey’s mate or food item. Several predators exploit plant–pollinator systems, where visual signals are an essential part of interspecific interactions. Many diurnal, and even nocturnal, orb-web spiders present conspicuous body coloration or bright color patches. These bright colors are regarded as color-based lures that exploit biases present in insect visual systems, possibly mimicking flower colors. The prey attraction hypothesis was proposed more than 20 years ago to explain orb-web spider coloration. Although most data gathered so far has corroborated the predictions of the prey attraction hypothesis, there are several studies that refute these predictions. We conducted a multilevel phylogenetic meta-analysis to assess the magnitude of the effect of conspicuous orb-web spider body coloration on prey attraction. We found a positive effect in favor of the prey attraction hypothesis; however, there was substantial heterogeneity between studies. Experimental designs comparing conspicuous spiders to painted spiders or empty webs did not explain between-studies heterogeneity. The lack of theoretical explanation behind the prey attraction hypothesis makes it challenging to address which components influence prey attraction. Future studies could evaluate whether color is part of a multicomponent signal and test alternative hypotheses for the evolution of spider colors, such as predator avoidance and thermoregulation.
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19
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Wu S, Chang CM, Mai GS, Rubenstein DR, Yang CM, Huang YT, Lin HH, Shih LC, Chen SW, Shen SF. Artificial intelligence reveals environmental constraints on colour diversity in insects. Nat Commun 2019; 10:4554. [PMID: 31591404 PMCID: PMC6779759 DOI: 10.1038/s41467-019-12500-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 09/10/2019] [Indexed: 11/09/2022] Open
Abstract
Explaining colour variation among animals at broad geographic scales remains challenging. Here we demonstrate how deep learning-a form of artificial intelligence-can reveal subtle but robust patterns of colour feature variation along an ecological gradient, as well as help identify the underlying mechanisms generating this biogeographic pattern. Using over 20,000 images with precise GPS locality information belonging to nearly 2,000 moth species from Taiwan, our deep learning model generates a 2048-dimension feature vector that accurately predicts each species' mean elevation based on colour and shape features. Using this multidimensional feature vector, we find that within-assemblage image feature variation is smaller in high elevation assemblages. Structural equation modeling suggests that this reduced image feature diversity is likely the result of colder environments selecting for darker colouration, which limits the colour diversity of assemblages at high elevations. Ultimately, with the help of deep learning, we will be able to explore the endless forms of natural morphological variation at unpreceded depths.
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Affiliation(s)
- Shipher Wu
- Biodiversity Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Chun-Min Chang
- Institute of Information Science, Academia Sinica, Taipei, 11529, Taiwan
| | - Guan-Shuo Mai
- Biodiversity Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Dustin R Rubenstein
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, 10027, USA
- Center for Integrative Animal Behavior, Columbia University, New York, NY, 10027, USA
| | - Chen-Ming Yang
- Institute of Information Science, Academia Sinica, Taipei, 11529, Taiwan
| | - Yu-Ting Huang
- Institute of Information Science, Academia Sinica, Taipei, 11529, Taiwan
| | - Hsu-Hong Lin
- Taiwan Endemic Species Research Institute, Nantou, 552, Taiwan
| | - Li-Cheng Shih
- Taiwan Endemic Species Research Institute, Nantou, 552, Taiwan
| | - Sheng-Wei Chen
- Institute of Information Science, Academia Sinica, Taipei, 11529, Taiwan.
| | - Sheng-Feng Shen
- Biodiversity Research Center, Academia Sinica, Taipei, 11529, Taiwan.
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20
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Javůrková VG, Enbody ED, Kreisinger J, Chmel K, Mrázek J, Karubian J. Plumage iridescence is associated with distinct feather microbiota in a tropical passerine. Sci Rep 2019; 9:12921. [PMID: 31501471 PMCID: PMC6733896 DOI: 10.1038/s41598-019-49220-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 08/21/2019] [Indexed: 12/27/2022] Open
Abstract
Birds present a stunning diversity of plumage colors that have long fascinated evolutionary ecologists. Although plumage coloration is often linked to sexual selection, it may impact a number of physiological processes, including microbial resistance. At present, the degree to which differences between pigment-based vs. structural plumage coloration may affect the feather microbiota remains unanswered. Using quantitative PCR and DGGE profiling, we investigated feather microbial load, diversity and community structure among two allopatric subspecies of White-shouldered Fairywren, Malurus alboscapulatus that vary in expression of melanin-based vs. structural plumage coloration. We found that microbial load tended to be lower and feather microbial diversity was significantly higher in the plumage of black iridescent males, compared to black matte females and brown individuals. Moreover, black iridescent males had distinct feather microbial communities compared to black matte females and brown individuals. We suggest that distinctive nanostructure properties of iridescent male feathers or different investment in preening influence feather microbiota community composition and load. This study is the first to point to structural plumage coloration as a factor that may significantly regulate feather microbiota. Future work might explore fitness consequences and the role of microorganisms in the evolution of avian sexual dichromatism, with particular reference to iridescence.
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Affiliation(s)
- Veronika Gvoždíková Javůrková
- Faculty of Agrobiology, Food and Natural Resources, Department of Animal Science, Czech University of Life Sciences, Kamýcká 129, 165 00, Prague, Suchdol, Czech Republic.
- Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 65, Brno, Czech Republic.
| | - Erik D Enbody
- Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA, USA
| | - Jakub Kreisinger
- Faculty of Science, Department of Zoology, Charles University, Viničná 7, 128 44, Prague, Czech Republic
| | - Kryštof Chmel
- Faculty of Science, Department of Zoology, Charles University, Viničná 7, 128 44, Prague, Czech Republic
- Faculty of Science, Department of Zoology, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic
| | - Jakub Mrázek
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Vídeňská 1083, 160 00, Prague-Krč, Czech Republic
| | - Jordan Karubian
- Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA, USA
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21
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Sibeaux A, Cole GL, Endler JA. The relative importance of local and global visual contrast in mate choice. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.06.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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22
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Liao H, Liao C, Blamires SJ, Tso I. Multifunctionality of an arthropod predator’s body coloration. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13326] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Hsien‐Chun Liao
- Department of Life Science Tunghai University Taichung Taiwan
| | - Chen‐Pan Liao
- Department of Life Science Tunghai University Taichung Taiwan
- Department of Biology National Museum of Natural Science Taichung Taiwan
| | - Sean J. Blamires
- Department of Life Science Tunghai University Taichung Taiwan
- Evolution and Ecology Research Centre University of New South Wales Sydney New South Wales
| | - I‐Min Tso
- Department of Life Science Tunghai University Taichung Taiwan
- Center for Tropical Ecology and Biodiversity Tunghai University Taichung Taiwan
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23
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Renoult JP, Mendelson TC. Processing bias: extending sensory drive to include efficacy and efficiency in information processing. Proc Biol Sci 2019; 286:20190165. [PMID: 30940061 DOI: 10.1098/rspb.2019.0165] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Communication signals often comprise an array of colours, lines, spots, notes or odours that are arranged in complex patterns, melodies or blends. Receiver perception is assumed to influence preference and thus the evolution of signal design, but evolutionary biologists still struggle to understand how perception, preference and signal design are mechanistically linked. In parallel, the field of empirical aesthetics aims to understand why people like some designs more than others. The model of processing bias discussed here is rooted in empirical aesthetics, which posits that preferences are influenced by the emotional system as it monitors the dynamics of information processing and that attractive signals have effective designs that maximize information transmission, efficient designs that allow information processing at low metabolic cost, or both. We refer to the causal link between preference and the emotionally rewarding experience of effective and efficient information processing as the processing bias, and we apply it to the evolutionary model of sensory drive. A sensory drive model that incorporates processing bias hypothesizes a causal chain of relationships between the environment, perception, pleasure, preference and ultimately the evolution of signal design, both simple and complex.
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Affiliation(s)
- Julien P Renoult
- 1 Centre of Evolutionary and Functional Ecology (CEFE UMR5175), CNRS-University of Montpellier-University Paul-Valery Montpellier-EPHE) , 1919 route de Mende, 34293 Montpellier , France
| | - Tamra C Mendelson
- 2 Department of Biological Sciences, University of Maryland Baltimore County , 1000 Hilltop Circle, Baltimore, MD 21250 , USA
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24
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Klonoski K, Bi K, Rosenblum EB. Phenotypic and genetic diversity in aposematic Malagasy poison frogs (genus Mantella). Ecol Evol 2019; 9:2725-2742. [PMID: 30891212 PMCID: PMC6406014 DOI: 10.1002/ece3.4943] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/07/2018] [Accepted: 01/02/2019] [Indexed: 12/17/2022] Open
Abstract
Intraspecific color variation has long fascinated evolutionary biologists. In species with bright warning coloration, phenotypic diversity is particularly compelling because many factors, including natural and sexual selection, contribute to intraspecific variation. To better understand the causes of dramatic phenotypic variation in Malagasy poison frogs, we quantified genetic structure and color and pattern variation across three closely related species, Mantella aurantiaca, Mantella crocea, and Mantella milotympanum. Although our restriction site-associated DNA (RAD) sequencing approach identified clear genetic clusters, they do not align with current species designations, which has important conservation implications for these imperiled frogs. Moreover, our results suggest that levels of intraspecific color variation within this group have been overestimated, while species diversity has been underestimated. Within major genetic clusters, we observed distinct patterns of variation including: populations that are phenotypically similar yet genetically distinct, populations where phenotypic and genetic breaks coincide, and populations that are genetically similar but have high levels of within-population phenotypic variation. We also detected admixture between two of the major genetic clusters. Our study suggests that several mechanisms-including hybridization, selection, and drift-are contributing to phenotypic diversity. Ultimately, our work underscores the need for a reevaluation of how polymorphic and polytypic populations and species are classified, especially in aposematic organisms.
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Affiliation(s)
- Karina Klonoski
- Department of Environmental Science, Policy, and ManagementUniversity of California, BerkeleyBerkeleyCalifornia
- Museum of Vertebrate ZoologyUniversity of California, BerkeleyBerkeleyCalifornia
| | - Ke Bi
- Museum of Vertebrate ZoologyUniversity of California, BerkeleyBerkeleyCalifornia
- Computational Genomics Resource Laboratory (CGRL), California Institute for Quantitative Biosciences (QB3)University of California, BerkeleyBerkeleyCalifornia
| | - Erica Bree Rosenblum
- Department of Environmental Science, Policy, and ManagementUniversity of California, BerkeleyBerkeleyCalifornia
- Museum of Vertebrate ZoologyUniversity of California, BerkeleyBerkeleyCalifornia
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25
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Stoddard MC, Osorio D. Animal Coloration Patterns: Linking Spatial Vision to Quantitative Analysis. Am Nat 2019; 193:164-186. [DOI: 10.1086/701300] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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26
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Chan IZW, Stevens M, Todd PA. pat‐geom
: A software package for the analysis of animal patterns. Methods Ecol Evol 2019. [DOI: 10.1111/2041-210x.13131] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ian Z. W. Chan
- Experimental Marine Ecology LaboratoryDepartment of Biological SciencesNational University of Singapore Singapore
| | - Martin Stevens
- Centre for Ecology and ConservationUniversity of Exeter Penryn Cornwall UK
| | - Peter A. Todd
- Experimental Marine Ecology LaboratoryDepartment of Biological SciencesNational University of Singapore Singapore
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27
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Vargas R, Mackenzie S, Rey S. 'Love at first sight': The effect of personality and colouration patterns in the reproductive success of zebrafish (Danio rerio). PLoS One 2018; 13:e0203320. [PMID: 30231039 PMCID: PMC6145548 DOI: 10.1371/journal.pone.0203320] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 08/17/2018] [Indexed: 01/07/2023] Open
Abstract
Individual differences in animal personality and external appearance such as colouration patterns have both been extensively studied separately. A significant body of research has explored many of pertinent ecological and biological aspects that can be affected by them and their impact upon fitness. Currently little is known about how both factors interact and their effect on reproductive success. In this study, we evaluated two major parameters contributing to the fitness of the species: reproduction and offspring survival. We selected two different phenotypes of the zebrafish (Danio rerio) selected by their colouration patterns: phenotype 1) named Wild type, UAB line (WT-UAB) with a homogeneous colouration pattern (clear and defined lateral stripes) and phenotype 2) Wild type indefinite (WT-I) had a heterogeneous colouration pattern and different degrees of lateral stripe definition. All animals were also screened for personality. We then compared their reproductive success (spawning rate) and offspring survival at different stages, from egg to larvae, and for 2 successive generations (parental generation was G0; First and second generations were G1 and G2 respectively). Our results show that personality traits were the main source of variability between the fitness components measured: both personalities had similar total numbers of eggs spawned but proactive animals, for both colour phenotypes, had higher reproductive success. This was reflected in a higher percentage of spawning viability at 1day post fertilization (dpf), higher total survival and growth rates at larval stages. Proactive phenotypes from WT-UAB population had a higher overall fitness in comparison to the other phenotypes studied. Our findings imply that fitness of this species when kept under similar husbandry conditions is significantly influenced by parental personality and not by their external appearance. Under these conditions the reproductive success is enhanced. The implications of this study are important for zebrafish breeding and husbandry in captivity and are relevant toward understanding the underlying drivers of trait selection in natural environments.
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Affiliation(s)
- Reynaldo Vargas
- Departamento de Biología Marina y Limnología, Extensión Universitaria de Aguadulce, Universidad de Panamá, Aguadulce, Coclé, República de Panamá
| | - Simon Mackenzie
- Institute of Aquaculture, University of Stirling, Stirling, Scotland, United Kingdom
| | - Sonia Rey
- Institute of Aquaculture, University of Stirling, Stirling, Scotland, United Kingdom
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28
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Cantarero A, Carrasco Naranjo J, Casas F, Mougeot F, Viñuela J, Alonso-Alvarez C. The fractal dimension of a conspicuous ornament varies with mating status and shows assortative mating in wild red-legged partridges (Alectoris rufa). THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 2018; 105:45. [PMID: 29959540 DOI: 10.1007/s00114-018-1565-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 04/26/2018] [Accepted: 05/21/2018] [Indexed: 11/27/2022]
Abstract
Complex body designs, such as plumage ornaments in birds, can be described by fractal geometry. These complex patterns could have a role as visual signals during courtship and social interactions, but an empirical validation in the wild is currently lacking. Here, we investigated whether the fractal dimension (FD) of a complex plumage pattern displayed by red-legged partridges Alectoris rufa could function as a potential sexual signal. We captured wild birds early in the breeding season and tested if mated and unmated birds differed in the FD of their conspicuous melanin-based black bib. We also tested if the FD of the black bib was correlated within the pair, looking for evidence of assortative mating based on the expression of this trait. We simultaneously assessed similar effects in other ornamental traits (black bib size, white throat patch and black flank band surface, redness of the eye rings and bill). Mated birds showed higher black bib FD values than unmated ones. Mated males, but not females, also displayed a larger black bib. Moreover, the black bib FD (but not the trait size) and the white throat patch surface showed assortative mating. Finally, females with higher black bib FD showed smaller black flank band surface, suggesting a trade-off in the expression of the two melanin-pigmented plumage traits. This provides unique and novel indication for the shape complexity of a pigmented trait, here described by its fractal dimension, to be potentially under sexual selection in a wild animal.
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Affiliation(s)
- Alejandro Cantarero
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain.
| | - Jesús Carrasco Naranjo
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo 12, 13005, Ciudad Real, Spain
| | - Fabián Casas
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo 12, 13005, Ciudad Real, Spain
- Estación Experimental de Zonas Áridas (EEZA-CSIC), Carretera de Sacramento s/n. 04120 La Cañada de San Urbano, Almería, Spain
- Department of Biology, University of Maryland, College Park, MD, 20742, USA
| | - Francois Mougeot
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo 12, 13005, Ciudad Real, Spain
| | - Javier Viñuela
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo 12, 13005, Ciudad Real, Spain
| | - Carlos Alonso-Alvarez
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain
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29
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Soma M, Garamszegi LZ. Evolution of patterned plumage as a sexual signal in estrildid finches. Behav Ecol 2018. [DOI: 10.1093/beheco/ary021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Masayo Soma
- Department of Biology, Faculty of Science, Hokkaido University, Kita-ku, Sapporo, Hokkaido, Japan
| | - László Zsolt Garamszegi
- Department of Evolutionary Ecology, Estación Biológica de Doñana-CSIC, c/Americo Vespucio, Seville, Spain
- MTA-ELTE, Theoretical Biology and Evolutionary Ecology Research Group, Department of Plant Systematics, Ecology and Theoretical Biology, Eötvös Loránd University, Pázmány Péter sétány, Budapest, Hungary
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