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Henríquez-Piskulich P, Stuart-Fox D, Elgar M, Marusic I, Franklin AM. Dazzled by shine: gloss as an antipredator strategy in fast moving prey. Behav Ecol 2023; 34:862-871. [PMID: 37744168 PMCID: PMC10516678 DOI: 10.1093/beheco/arad046] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/06/2023] [Accepted: 05/23/2023] [Indexed: 09/26/2023] Open
Abstract
Previous studies on stationary prey have found mixed results for the role of a glossy appearance in predator avoidance-some have found that glossiness can act as warning coloration or improve camouflage, whereas others detected no survival benefit. An alternative untested hypothesis is that glossiness could provide protection in the form of dynamic dazzle. Fast moving animals that are glossy produce flashes of light that increase in frequency at higher speeds, which could make it harder for predators to track and accurately locate prey. We tested this hypothesis by presenting praying mantids with glossy or matte targets moving at slow and fast speed. Mantids were less likely to strike glossy targets, independently of speed. Additionally, mantids were less likely to track glossy targets and more likely to hit the target with one out of the two legs that struck rather than both raptorial legs, but only when targets were moving fast. These results support the hypothesis that a glossy appearance may have a function as an antipredator strategy by reducing the ability of predators to track and accurately target fast moving prey.
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Affiliation(s)
| | - Devi Stuart-Fox
- School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Mark Elgar
- School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ivan Marusic
- Department of Mechanical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Amanda M Franklin
- School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia
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2
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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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3
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Pacheco MA, Ferreira FC, Logan CJ, McCune KB, MacPherson MP, Albino Miranda S, Santiago-Alarcon D, Escalante AA. Great-tailed Grackles (Quiscalus mexicanus) as a tolerant host of avian malaria parasites. PLoS One 2022; 17:e0268161. [PMID: 35998118 PMCID: PMC9397854 DOI: 10.1371/journal.pone.0268161] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/29/2022] [Indexed: 11/18/2022] Open
Abstract
Great-tailed Grackles (Quiscalus mexicanus) are a social, polygamous bird species whose populations have rapidly expanded their geographic range across North America over the past century. Before 1865, Great-tailed Grackles were only documented in Central America, Mexico, and southern Texas in the USA. Given the rapid northern expansion of this species, it is relevant to study its role in the dynamics of avian blood parasites. Here, 87 Great-tailed grackles in Arizona (a population in the new center of the range) were screened for haemosporidian parasites using microscopy and PCR targeting the parasite mitochondrial cytochrome b gene. Individuals were caught in the wild from January 2018 until February 2020. Haemosporidian parasite prevalence was 62.1% (54/87). A high Plasmodium prevalence was found (60.9%, 53/87), and one grackle was infected with Haemoproteus (Parahaemoproteus) sp. (lineage SIAMEX01). Twenty-one grackles were infected with P. cathemerium, sixteen with P. homopolare, four with P. relictum (strain GRW04), and eleven with three different genetic lineages of Plasmodium spp. that have not been characterized to species level (MOLATE01, PHPAT01, and ZEMAC01). Gametocytes were observed in birds infected with three different Plasmodium lineages, revealing that grackles are competent hosts for some parasite species. This study also suggests that grackles are highly susceptible and develop chronic infections consistent with parasite tolerance, making them competent to transmit some generalist haemosporidian lineages. It can be hypothesized that, as the Great-tailed Grackle expands its geographic range, it may affect local bird communities by increasing the transmission of local parasites but not introducing new species into the parasite species pool.
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Affiliation(s)
- M. Andreína Pacheco
- Biology Department/Institute of Genomics and Evolutionary Medicine (iGEM), Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail: (CJL); (MAP); (AAE)
| | - Francisco C. Ferreira
- Center for Conservation Genomics, Smithsonian Conservation Biology Institute, Washington, DC, United States of America
- Center for Vector Biology, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Corina J. Logan
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- * E-mail: (CJL); (MAP); (AAE)
| | - Kelsey B. McCune
- University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Maggie P. MacPherson
- University of California, Santa Barbara, Santa Barbara, California, United States of America
- Louisiana State University Museum of Natural Science, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Sergio Albino Miranda
- Red de Biología y Conservación de Vertebrados, Instituto de Ecología, Xalapa, Veracruz, Mexico
| | - Diego Santiago-Alarcon
- Department of Integrative Biology, University of South Florida, Tampa, Florida, United States of America
| | - Ananias A. Escalante
- Biology Department/Institute of Genomics and Evolutionary Medicine (iGEM), Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail: (CJL); (MAP); (AAE)
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4
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Vector-Borne Blood Parasites of the Great-Tailed Grackle ( Quiscalus mexicanus) in East-Central Texas, USA. Microorganisms 2021; 9:microorganisms9030504. [PMID: 33673608 PMCID: PMC7997132 DOI: 10.3390/microorganisms9030504] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 12/29/2022] Open
Abstract
Great-tailed grackles (Quiscalus mexicanus) have dramatically expanded into North America over the past century. However, little is known about the blood that parasites they support. Here, for the first time, we document an assemblage of trypanosome, haemosporida, and filarial nematodes co-circulating in invasive great-tailed grackles. Between February and July, 2015, 61 individuals were captured in an urban environment of College Station, Texas. Field microscopy and molecular diagnostics indicate that 52% (24/46) were visually infected with filarioid nematodes, 24% (11/46) with avian trypanosomes, and 73% (n = 44/60) with haemosporida parasites, such as Haemoproteus (Parahaemoproteus) and Plasmodium cathemerium. Overall, 87% of great-tailed grackles were infected with blood parasites. Although 50% of individuals hosted parasites from multiple phylum, no patterns of parasite assembly were observed. Results indicate that great-tailed grackles can support a relatively high level of blood parasitism. However, the consequences for avian health remain to be determined.
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Abstract
Amanda M. Franklin and Laura Ospina-Rozo introduce the biology and physics of gloss in nature.
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Shawkey MD, D'Alba L. Interactions between colour-producing mechanisms and their effects on the integumentary colour palette. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0536. [PMID: 28533449 DOI: 10.1098/rstb.2016.0536] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2017] [Indexed: 11/12/2022] Open
Abstract
Animal integumentary coloration plays a crucial role in visual communication and camouflage, and varies extensively among and within species and populations. To understand the pressures underlying such diversity, it is essential to elucidate the mechanisms by which animals have created novel integumentary coloration. Colours can be produced by selective absorption of light by skin pigments, through light scattering by structured or unstructured tissues, or by a combination of pigments and nanostructures. In this review, we highlight our current understanding of the interactions between pigments and structural integumentary tissues and molecules. We analyse the available evidence suggesting that these combined mechanisms are capable of creating colours and optical properties unachievable by either mechanism alone, thereby effectively expanding the animal colour palette. Moreover, structural and pigmentary colour mechanisms frequently interact in unexpected and overlooked ways, suggesting that classification of colours as being of any particular type may be difficult. Finally, we discuss how these mixtures are useful for investigating the largely unknown genetic, developmental and physical processes generating phenotypic diversity.This article is part of the themed issue 'Animal coloration: production, perception, function and application'.
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Affiliation(s)
- Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, Ledeganckstraat 35, Ghent 9000, Belgium
| | - Liliana D'Alba
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, Ledeganckstraat 35, Ghent 9000, Belgium
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7
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Iskandar JP, Eliason CM, Astrop T, Igic B, Maia R, Shawkey MD. Morphological basis of glossy red plumage colours. Biol J Linn Soc Lond 2016. [DOI: 10.1111/bij.12810] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jean-Pierre Iskandar
- Integrated Bioscience Department; The University of Akron; 175 E. Mill St. Akron OH 44325-3908 USA
| | - Chad M. Eliason
- Integrated Bioscience Department; The University of Akron; 175 E. Mill St. Akron OH 44325-3908 USA
- Departments of Geological Sciences and Integrative Bioscience; University of Texas at Austin; 2305 Speedway Stop C1160 Austin TX 78712 USA
| | - Tim Astrop
- Integrated Bioscience Department; The University of Akron; 175 E. Mill St. Akron OH 44325-3908 USA
- Department of Biology & Biochemistry; University of Bath; Bath BA2 7AY UK
| | - Branislav Igic
- Integrated Bioscience Department; The University of Akron; 175 E. Mill St. Akron OH 44325-3908 USA
| | - Rafael Maia
- Integrated Bioscience Department; The University of Akron; 175 E. Mill St. Akron OH 44325-3908 USA
- Department of Ecology; Evolution and Environmental Biology; Columbia University; 1200 Amsterdam Avenue New York NY 10027 USA
| | - Matthew D. Shawkey
- Integrated Bioscience Department; The University of Akron; 175 E. Mill St. Akron OH 44325-3908 USA
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9
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Igic B, Fecheyr-Lippens D, Xiao M, Chan A, Hanley D, Brennan PRL, Grim T, Waterhouse GIN, Hauber ME, Shawkey MD. A nanostructural basis for gloss of avian eggshells. J R Soc Interface 2015; 12:rsif.2014.1210. [PMID: 25505139 DOI: 10.1098/rsif.2014.1210] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The role of pigments in generating the colour and maculation of birds' eggs is well characterized, whereas the effects of the eggshell's nanostructure on the visual appearance of eggs are little studied. Here, we examined the nanostructural basis of glossiness of tinamou eggs. Tinamou eggs are well known for their glossy appearance, but the underlying mechanism responsible for this optical effect is unclear. Using experimental manipulations in conjunction with angle-resolved spectrophotometry, scanning electron microscopy, atomic force microscopy and chemical analyses, we show that the glossy appearance of tinamou eggshells is produced by an extremely smooth cuticle, composed of calcium carbonate, calcium phosphate and, potentially, organic compounds such as proteins and pigments. Optical calculations corroborate surface smoothness as the main factor producing gloss. Furthermore, we reveal the presence of weak iridescence on eggs of the great tinamou (Tinamus major), an optical effect never previously documented for bird eggs. These data highlight the need for further exploration into the nanostructural mechanisms for the production of colour and other optical effects of avian eggshells.
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Affiliation(s)
- Branislav Igic
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH 44325, USA
| | - Daphne Fecheyr-Lippens
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH 44325, USA
| | - Ming Xiao
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Andrew Chan
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Daniel Hanley
- Department of Zoology and Laboratory of Ornithology, Palacký University, Olomouc 77146, Czech Republic
| | - Patricia R L Brennan
- Organismic and Evolutionary Biology Graduate Program, Department of Psychology, University of Massachusetts Amherst, Amherst, MA 01003, USA Department of Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Tomas Grim
- Department of Zoology and Laboratory of Ornithology, Palacký University, Olomouc 77146, Czech Republic
| | - Geoffrey I N Waterhouse
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Mark E Hauber
- Department of Psychology, Hunter College and the Graduate Center, The City University of New York, New York, NY 10065, USA
| | - Matthew D Shawkey
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH 44325, USA
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10
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Cahn MD, Brown AC, Clotfelter ED. Guanine-based structural coloration as an indicator of oxidative stress in a cichlid fish. ACTA ACUST UNITED AC 2015; 323:359-67. [DOI: 10.1002/jez.1926] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 01/30/2015] [Accepted: 02/02/2015] [Indexed: 01/09/2023]
Affiliation(s)
- Matthew D. Cahn
- Department of Biology; Amherst College; Amherst Massachusetts
| | - Alexandria C. Brown
- Department of Biology; Amherst College; Amherst Massachusetts
- Graduate Program in Organismic and Evolutionary Biology; University of Massachusetts; Amherst Massachusetts
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11
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Dalrymple RL, Hui FKC, Flores-Moreno H, Kemp DJ, Moles AT. Roses are red, violets are blue - so how much replication should you do? An assessment of variation in the colour of flowers and birds. Biol J Linn Soc Lond 2014. [DOI: 10.1111/bij.12402] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Rhiannon L. Dalrymple
- Evolution and Ecology Research Centre; School of Biological, Earth and Environmental Sciences; The University of New South Wales; Sydney NSW 2052 Australia
| | - Francis K. C. Hui
- Evolution and Ecology Research Centre; School of Biological, Earth and Environmental Sciences; The University of New South Wales; Sydney NSW 2052 Australia
- School of Mathematics and Statistics; University of New South Wales; Sydney NSW 2052 Australia
| | - Habacuc Flores-Moreno
- Evolution and Ecology Research Centre; School of Biological, Earth and Environmental Sciences; The University of New South Wales; Sydney NSW 2052 Australia
| | - Darrell J. Kemp
- Department of Biological Sciences; Macquarie University; Sydney NSW 2109 Australia
| | - Angela T. Moles
- Evolution and Ecology Research Centre; School of Biological, Earth and Environmental Sciences; The University of New South Wales; Sydney NSW 2052 Australia
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12
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Jiang L, Dong B, Liu X, Liu F, Zi J. Structural origin of sexual dichromatic coloration and luster in the beetle Goliathus cacicus. CHINESE SCIENCE BULLETIN-CHINESE 2012. [DOI: 10.1007/s11434-012-5343-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Li Q, Gao KQ, Meng Q, Clarke JA, Shawkey MD, D'Alba L, Pei R, Ellison M, Norell MA, Vinther J. Reconstruction ofMicroraptorand the Evolution of Iridescent Plumage. Science 2012; 335:1215-9. [PMID: 22403389 DOI: 10.1126/science.1213780] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Quanguo Li
- Beijing Museum of Natural History, 126 Tianqiao South Street, Beijing 100050, People's Republic of China
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Whitney HM, Rands SA, Elton NJ, Ellis AG. A technique for measuring petal gloss, with examples from the Namaqualand flora. PLoS One 2012; 7:e29476. [PMID: 22253729 PMCID: PMC3254604 DOI: 10.1371/journal.pone.0029476] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 11/29/2011] [Indexed: 11/19/2022] Open
Abstract
The degree of floral gloss varies between species. However, little is known about this distinctive floral trait, even though it could be a key feature of floral biotic and abiotic interactions. One reason for the absence of knowledge is the lack of a simple, repeatable method of gloss measurement that can be used in the field to study floral gloss. A protocol is described for measuring gloss in petal samples collected in the field, using a glossmeter. Repeatability of the technique is assessed. We demonstrate a simple yet highly accurate and repeatable method that can easily be implemented in the field. We also highlight the huge variety of glossiness found within flowers and between species in a sample of spring-blooming flowers collected in Namaqualand, South Africa. We discuss the potential uses of this method and its applications for furthering studies in plant-pollinator interactions. We also discuss the potential functions of gloss in flowers.
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Affiliation(s)
- Heather M Whitney
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom.
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15
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Shawkey MD, Maia R, D'Alba L. Proximate bases of silver color in anhinga (Anhinga anhinga) feathers. J Morphol 2011; 272:1399-407. [PMID: 21755527 DOI: 10.1002/jmor.10993] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 05/03/2011] [Accepted: 05/21/2011] [Indexed: 11/08/2022]
Abstract
Colors of living organisms are produced by selective light absorption from pigments and/or by light scattering from highly ordered nanostructures (i.e., structural color). While the physical bases of metallic colors of arthropods and fish are fairly well-known, those of birds are not. Here we examine structurally based silver color and its production in feathers of the waterbird species Anhinga. This achromatic color is distinguished from grey by high specular reflectance, from white by low diffuse reflectance, and from both by high gloss. Light and electron microscopy revealed three modifications of feathers likely leading to silver color. First, proximal barbules were highly elongated and contained glossy black color at their base and white color at their pennulum. Second, this glossy black portion contained a single outer layer of keratin weakly bounded by melanosomes. Finally, the white portion contained a disordered amorphous matrix of keratin and air. Optical analyzes suggest that these structures produce, respectively, glossy black color through thin-film interference and white color through incoherent light scattering. Silver color likely results from the combined reflectance of these adjacent structures. This represents a distinct mechanism for attaining silver colors that may have been partially derived through selection for display, thermoregulation or decreased hydrophobicity.
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Affiliation(s)
- Matthew D Shawkey
- Integrated Bioscience Program, Department of Biology, The University of Akron, Akron, Ohio 44325, USA.
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16
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Maia R, D'Alba L, Shawkey MD. What makes a feather shine? A nanostructural basis for glossy black colours in feathers. Proc Biol Sci 2010; 278:1973-80. [PMID: 21123257 DOI: 10.1098/rspb.2010.1637] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Colours in feathers are produced by pigments or by nanostructurally organized tissues that interact with light. One of the simplest nanostructures is a single layer of keratin overlying a linearly organized layer of melanosomes that create iridescent colours of feather barbules through thin-film interference. Recently, it has been hypothesized that glossy (i.e. high specular reflectance) black feathers may be evolutionarily intermediate between matte black and iridescent feathers, and thus have a smooth keratin layer that produces gloss, but not the layered organization of melanosomes needed for iridescence. However, the morphological bases of glossiness remain unknown. Here, we use a theoretical approach to generate predictions about morphological differences between matte and glossy feathers that we then empirically test. Thin-film models predicted that glossy spectra would result from a keratin layer 110-180 nm thick and a melanin layer greater than 115 nm thick. Transmission electron microscopy data show that nanostructure of glossy barbules falls well within that range, but that of matte barbules does not. Further, glossy barbules had a thinner and more regular keratin cortex, as well as a more continuous underlying melanin layer, than matte barbules. Thus, their quasi-ordered nanostructures are morphologically intermediate between matte black and iridescent feathers, and perceived gloss may be a form of weakly chromatic iridescence.
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Affiliation(s)
- Rafael Maia
- Department of Biology, Integrated Bioscience Program, University of Akron, Akron, OH 44325-3908, USA.
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