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Eliason CM, Cooper JC, Hackett SJ, Zahnle E, Pequeño Saco TZ, Maddox JD, Hains T, Hauber ME, Bates JM. Interspecific hybridization explains rapid gorget colour divergence in Heliodoxa hummingbirds (Aves: Trochilidae). ROYAL SOCIETY OPEN SCIENCE 2023; 10:221603. [PMID: 36866078 PMCID: PMC9974296 DOI: 10.1098/rsos.221603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
Hybridization is a known source of morphological, functional and communicative signal novelty in many organisms. Although diverse mechanisms of established novel ornamentation have been identified in natural populations, we lack an understanding of hybridization effects across levels of biological scales and upon phylogenies. Hummingbirds display diverse structural colours resulting from coherent light scattering by feather nanostructures. Given the complex relationship between feather nanostructures and the colours they produce, intermediate coloration does not necessarily imply intermediate nanostructures. Here, we characterize nanostructural, ecological and genetic inputs in a distinctive Heliodoxa hummingbird from the foothills of eastern Peru. Genetically, this individual is closely allied with Heliodoxa branickii and Heliodoxa gularis, but it is not identical to either when nuclear data are assessed. Elevated interspecific heterozygosity further suggests it is a hybrid backcross to H. branickii. Electron microscopy and spectrophotometry of this unique individual reveal key nanostructural differences underlying its distinct gorget colour, confirmed by optical modelling. Phylogenetic comparative analysis suggests that the observed gorget coloration divergence from both parentals to this individual would take 6.6-10 My to evolve at the current rate within a single hummingbird lineage. These results emphasize the mosaic nature of hybridization and suggest that hybridization may contribute to the structural colour diversity found across hummingbirds.
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Affiliation(s)
- Chad M. Eliason
- Negaunee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
- Grainger Bioinformatics Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
| | - Jacob C. Cooper
- Negaunee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
- Biodiversity Institute, University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS 66044, USA
- Directora de Monitoreo y Evaluacion de Recursos Naturales del Territorio, Plataforma digital única del Estado Peruano, Iquitos, Perú
| | - Shannon J. Hackett
- Negaunee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
- Pritzker Laboratory for Molecular Systematics and Evolution, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
| | - Erica Zahnle
- Biodiversity Institute, University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS 66044, USA
| | - Tatiana Z. Pequeño Saco
- Laboratorio de Biotecnología y Bioenergética, Universidad Científica del Perú, Iquitos, Perú
| | - Joseph Dylan Maddox
- Pritzker Laboratory for Molecular Systematics and Evolution, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
- Laboratorio de Biotecnología y Bioenergética, Universidad Científica del Perú, Iquitos, Perú
| | - Taylor Hains
- Negaunee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
- Pritzker Laboratory for Molecular Systematics and Evolution, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
| | - Mark E. Hauber
- Department of Evolution, Ecology, and Behaviour, School at Integrative Biology, University of Illinois, Urbana-Champaign, IL 61801, USA
| | - John M. Bates
- Negaunee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA
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Marques P, Zandonà E, Amaral J, Selhorst Y, El-Sabaawi R, Mazzoni R, Castro L, Pilastro A. Using fish to understand how cities affect sexual selection before and after mating. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.928277] [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
Urbanization transforms natural and agricultural areas into built landscapes. Such profound habitat alteration imposes strong pressure on phenotypic trait changes through processes related to natural and/or sexual selection. Evidence of how natural selection drives changes to traits in urban biota is increasing, but little is known about the role of sexual selection. In this study, we assessed the effect of urbanization on the expression and interaction of males' pre-mating traits (body size and color) and a post-mating trait (sperm load). We used a widespread invasive species, the guppy (Poecilia reticulata), which is a wellknown model for studying sexual selection, but have never been studied in urban systems for this purpose. We found that urbanization did not affect mean body size or condition, but it resulted in size-dependent reductions in the expression of orange and iridescent colors, as well as sperm load. The orange color was reduced in small urban guppies, while the iridescent colors were reduced in large urban guppies compared to non-urban guppies. The difference in sperm load was only found in large males, with lower sperm load in urban guppies. The relationship between orange color and sperm load was positive in urban guppies but negative in non-urban guppies, while the association between iridescent color and sperm load followed the opposite pattern. Our findings suggest that sexual selection on pre- and post-mating traits is weaker in urban than in non-urban systems and that interactions between such traits are context dependent. These responses can be related to the pollution and altered visual environment of urban systems and provide an opportunity to advance our understanding of the mechanisms determining adaptation in cities.
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3
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Nordén KK, Eliason CM, Stoddard MC. Evolution of brilliant iridescent feather nanostructures. eLife 2021; 10:e71179. [PMID: 34930526 PMCID: PMC8691833 DOI: 10.7554/elife.71179] [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: 06/11/2021] [Accepted: 11/19/2021] [Indexed: 12/19/2022] Open
Abstract
The brilliant iridescent plumage of birds creates some of the most stunning color displays known in the natural world. Iridescent plumage colors are produced by nanostructures in feathers and have evolved in diverse birds. The building blocks of these structures-melanosomes (melanin-filled organelles)-come in a variety of forms, yet how these different forms contribute to color production across birds remains unclear. Here, we leverage evolutionary analyses, optical simulations, and reflectance spectrophotometry to uncover general principles that govern the production of brilliant iridescence. We find that a key feature that unites all melanosome forms in brilliant iridescent structures is thin melanin layers. Birds have achieved this in multiple ways: by decreasing the size of the melanosome directly, by hollowing out the interior, or by flattening the melanosome into a platelet. The evolution of thin melanin layers unlocks color-producing possibilities, more than doubling the range of colors that can be produced with a thick melanin layer and simultaneously increasing brightness. We discuss the implications of these findings for the evolution of iridescent structures in birds and propose two evolutionary paths to brilliant iridescence.
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Affiliation(s)
- Klara Katarina Nordén
- Department of Ecology and Evolutionary Biology, Princeton UniversityPrincetonUnited States
| | - Chad M Eliason
- Grainger Bioinformatics Center, Field Museum of Natural HistoryChicagoUnited States
| | - Mary Caswell Stoddard
- Department of Ecology and Evolutionary Biology, Princeton UniversityPrincetonUnited States
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4
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White TE, Locke A, Latty T. Heightened condition dependent expression of structural coloration in the faces, but not wings, of male and female flies. Curr Zool 2021; 68:600-607. [PMID: 36324536 PMCID: PMC9616059 DOI: 10.1093/cz/zoab087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022] Open
Abstract
Structurally colored sexual signals are a conspicuous and widespread class of ornament used in mate choice, though the extent to which they encode information on the quality of their bearers is not fully resolved. Theory predicts that signaling traits under strong sexual selection as honest indicators should evolve to be more developmentally integrated and exaggerated than nonsexual traits, thereby leading to heightened condition dependence. Here, we test this prediction through examination of the sexually dimorphic faces and wings of the cursorial fly Lispe cana. Males and females possess structural UV-white and golden faces, respectively, and males present their faces and wings to females during close-range, ground-based courtship displays, thereby creating the opportunity for mutual inspection. Across a field-collected sample of individuals, we found that the appearance of the faces of both sexes scaled positively with individual condition, though along separate axes. Males in better condition expressed brighter faces as modeled according to conspecific flies, whereas condition scaled with facial saturation in females. We found no such relationships for their wing interference pattern nor abdomens, with the latter included as a nonsexual control. Our results suggest that the structurally colored faces, but not the iridescent wings, of male and female L. cana are reliable guides to individual quality and support the broader potential for structural colors as honest signals. They also highlight the potential for mutual mate choice in this system, while arguing for 1 of several alternate signaling roles for wing interferences patterns among the myriad taxa which bear them.
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Affiliation(s)
- Thomas E White
- School of Life and Environmental Sciences, The University of Sydney, Sydney 2106, Australia
| | - Amy Locke
- School of Life and Environmental Sciences, The University of Sydney, Sydney 2106, Australia
| | - Tanya Latty
- School of Life and Environmental Sciences, The University of Sydney, Sydney 2106, Australia
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5
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Jeon DJ, Paik S, Ji S, Yeo JS. Melanin-based structural coloration of birds and its biomimetic applications. Appl Microsc 2021; 51:14. [PMID: 34633588 PMCID: PMC8505553 DOI: 10.1186/s42649-021-00063-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/24/2021] [Indexed: 11/29/2022] Open
Abstract
Melanin has been a widely researched pigment by scientists for decades as it is undoubtedly the most ubiquitous and ancient pigment found in nature. Melanin plays very significant roles in structural plumage colors in birds: it has visible light-absorbing capabilities, and nanoscale structures can be formed by self-assembling melanin granules. Herein, we review recent progress on melanin-based structural coloration research. We hope that this review will provide current understanding of melanin's structural and optical properties, natural coloration mechanisms, and biomimetic methods to implement artificial melanin-based structural colors.
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Affiliation(s)
- Deok-Jin Jeon
- School of Integrated Technology, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea
- Yonsei Institute of Convergence Technology, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea
| | - Suejeong Paik
- 39 Yeonhui-ro 22-gil, Seodaemun-gu, Seoul, 03723, Republic of Korea
| | - Seungmuk Ji
- School of Integrated Technology, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea
- Yonsei Institute of Convergence Technology, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea
| | - Jong-Souk Yeo
- School of Integrated Technology, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea.
- Yonsei Institute of Convergence Technology, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea.
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6
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Price-Waldman R, Stoddard MC. Avian Coloration Genetics: Recent Advances and Emerging Questions. J Hered 2021; 112:395-416. [PMID: 34002228 DOI: 10.1093/jhered/esab015] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
The colorful phenotypes of birds have long provided rich source material for evolutionary biologists. Avian plumage, beaks, skin, and eggs-which exhibit a stunning range of cryptic and conspicuous forms-inspired early work on adaptive coloration. More recently, avian color has fueled discoveries on the physiological, developmental, and-increasingly-genetic mechanisms responsible for phenotypic variation. The relative ease with which avian color traits can be quantified has made birds an attractive system for uncovering links between phenotype and genotype. Accordingly, the field of avian coloration genetics is burgeoning. In this review, we highlight recent advances and emerging questions associated with the genetic underpinnings of bird color. We start by describing breakthroughs related to 2 pigment classes: carotenoids that produce red, yellow, and orange in most birds and psittacofulvins that produce similar colors in parrots. We then discuss structural colors, which are produced by the interaction of light with nanoscale materials and greatly extend the plumage palette. Structural color genetics remain understudied-but this paradigm is changing. We next explore how colors that arise from interactions among pigmentary and structural mechanisms may be controlled by genes that are co-expressed or co-regulated. We also identify opportunities to investigate genes mediating within-feather micropatterning and the coloration of bare parts and eggs. We conclude by spotlighting 2 research areas-mechanistic links between color vision and color production, and speciation-that have been invigorated by genetic insights, a trend likely to continue as new genomic approaches are applied to non-model species.
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7
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Rubenstein DR, Corvelo A, MacManes MD, Maia R, Narzisi G, Rousaki A, Vandenabeele P, Shawkey MD, Solomon J. Feather Gene Expression Elucidates the Developmental Basis of Plumage Iridescence in African Starlings. J Hered 2021; 112:417-429. [PMID: 33885791 DOI: 10.1093/jhered/esab014] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/19/2021] [Indexed: 01/08/2023] Open
Abstract
Iridescence is widespread in the living world, occurring in organisms as diverse as bacteria, plants, and animals. Yet, compared to pigment-based forms of coloration, we know surprisingly little about the developmental and molecular bases of the structural colors that give rise to iridescence. Birds display a rich diversity of iridescent structural colors that are produced in feathers by the arrangement of melanin-containing organelles called melanosomes into nanoscale configurations, but how these often unusually shaped melanosomes form, or how they are arranged into highly organized nanostructures, remains largely unknown. Here, we use functional genomics to explore the developmental basis of iridescent plumage using superb starlings (Lamprotornis superbus), which produce both iridescent blue and non-iridescent red feathers. Through morphological and chemical analyses, we confirm that hollow, flattened melanosomes in iridescent feathers are eumelanin-based, whereas melanosomes in non-iridescent feathers are solid and amorphous, suggesting that high pheomelanin content underlies red coloration. Intriguingly, the nanoscale arrangement of melanosomes within the barbules was surprisingly similar between feather types. After creating a new genome assembly, we use transcriptomics to show that non-iridescent feather development is associated with genes related to pigmentation, metabolism, and mitochondrial function, suggesting non-iridescent feathers are more energetically expensive to produce than iridescent feathers. However, iridescent feather development is associated with genes related to structural and cellular organization, suggesting that, while nanostructures themselves may passively assemble, barbules and melanosomes may require active organization to give them their shape. Together, our analyses suggest that iridescent feathers form through a combination of passive self-assembly and active processes.
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Affiliation(s)
- Dustin R Rubenstein
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY
- Center for Integrative Animal Behavior, Columbia University, New York, NY
| | | | - Matthew D MacManes
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH
| | - Rafael Maia
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY
| | | | - Anastasia Rousaki
- Raman Spectroscopy Research Group, Department of Chemistry, Ghent University, Krigslaan, Ghent, Belgium
| | - Peter Vandenabeele
- Raman Spectroscopy Research Group, Department of Chemistry, Ghent University, Krigslaan, Ghent, Belgium
- Archaeometry Research Group, Department of Archaeology, Ghent University, Sint-Pietersnieuwstraat, Ghent, Belgium
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, Ghent University, Ghent, Belgium
| | - Joseph Solomon
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY
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Rogalla S, Patil A, Dhinojwala A, Shawkey MD, D'Alba L. Enhanced photothermal absorption in iridescent feathers. J R Soc Interface 2021; 18:20210252. [PMID: 34343456 PMCID: PMC8331237 DOI: 10.1098/rsif.2021.0252] [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: 03/24/2021] [Accepted: 07/13/2021] [Indexed: 01/15/2023] Open
Abstract
The diverse colours of bird feathers are produced by both pigments and nanostructures, and can have substantial thermal consequences. This is because reflectance, transmittance and absorption of differently coloured tissues affect the heat loads acquired from solar radiation. Using reflectance measurements and heating experiments on sunbird museum specimens, we tested the hypothesis that colour and their colour producing mechanisms affect feather surface heating and the heat transferred to skin level. As predicted, we found that surface temperatures were strongly correlated with plumage reflectivity when exposed to a radiative heat source and, likewise, temperatures reached at skin level decreased with increasing reflectivity. Indeed, nanostructured melanin-based iridescent feathers (green, purple, blue) reflected less light and heated more than unstructured melanin-based colours (grey, brown, black), as well as olives, carotenoid-based colours (yellow, orange, red) and non-pigmented whites. We used optical and heat modelling to test if differences in nanostructuring of melanin, or the bulk melanin content itself, better explains the differences between melanin-based feathers. These models showed that the greater melanin content and, to a lesser extent, the shape of the melanosomes explain the greater photothermal absorption in iridescent feathers. Our results suggest that iridescence can increase heat loads, and potentially alter birds' thermal balance.
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Affiliation(s)
- Svana Rogalla
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Anvay Patil
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, OH 44325, USA
| | - Ali Dhinojwala
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, OH 44325, USA
| | - Matthew D. Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Liliana D'Alba
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
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9
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D'Alba L, Meadows M, Maia R, Jong-Souk Y, Manceau M, Shawkey M. Morphogenesis of iridescent feathers in Anna's hummingbird Calypte anna. Integr Comp Biol 2021; 61:1502-1510. [PMID: 34104966 DOI: 10.1093/icb/icab123] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/01/2021] [Accepted: 06/07/2021] [Indexed: 12/15/2022] Open
Abstract
Color is a phenotypic trait of utmost importance, particularly in birds, which are known for their diverse color signals and color-producing mechanisms including pigment-based colors, light scattering from nanostructured feather tissues and combinations thereof. Bright iridescent plumage colors of hummingbirds are caused by light scattering by an organized array of flattened, pigment organelles, containing air-filled vesicles, called melanosomes. These hollow platelets are organized in multilayer arrays that contain numerous sharp air/melanin refractive index interfaces, producing brilliant iridescent colors. Despite their ecological significance and potential for inspiration of new optical materials, how platelets form and spatially arrange in nanostructures in growing feathers remains unknown. Here, we tested the hypothesis that melanosome formation and organization occurs mostly through passive self-assembly processes by assembling a developmental time series of growing hummingbird feathers using optical and electron microscopy. We show that hummingbird platelets contain air bubbles or vesicles upon their formation in pigment-producing cells, melanocytes. When melanosomes are transferred to neighboring keratinocytes (the cells shaping barbule structure) they drastically expand in size; and variation in this enlargement appears to be driven by physical constraints caused by the placement of the melanosomes within the barbule plate and their proximity to other melanosomes. As the barbule elongates and narrows, polymerizing feather corneous beta protein (CβP) orients melanosomes unilaterally, forcing them into a stacked configuration. These results reveal potentially novel forces driving the self-assembly of the nanostructures producing some of the brightest colors in nature.<.
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Affiliation(s)
- Liliana D'Alba
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, Ledeganckstraat 35, Ghent 9000, Belgium
| | - Melissa Meadows
- Department of Biology, University of Florida, 220 Bartram Hall, Gainesville, FL 32611-8525
| | - Rafael Maia
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY
| | - Yeo Jong-Souk
- School of Integrated Technology, Yonsei University, Incheon, 21983, Republic of Korea
| | - Marie Manceau
- Center for Interdisciplinary Research in Biology, CNRS 7241, INSERM U1050, Collège de France, Paris, France
| | - Matthew Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, Ledeganckstraat 35, Ghent 9000, Belgium
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10
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Decoding the Evolution of Melanin in Vertebrates. Trends Ecol Evol 2021; 36:430-443. [DOI: 10.1016/j.tree.2020.12.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 12/18/2020] [Accepted: 12/23/2020] [Indexed: 02/08/2023]
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11
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Saranathan V, Finet C. Cellular and developmental basis of avian structural coloration. Curr Opin Genet Dev 2021; 69:56-64. [PMID: 33684846 DOI: 10.1016/j.gde.2021.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 10/22/2022]
Abstract
Vivid structural colors in birds are a conspicuous and vital part of their phenotype. They are produced by a rich diversity of integumentary photonic nanostructures in skin and feathers. Unlike pigmentary coloration, whose genetic basis is being elucidated, little is known regarding the pathways underpinning organismal structural coloration. Here, we review available data on the development of avian structural colors. In particular, feather photonic nanostructures are understood to be intracellularly self-assembled by physicochemical forces typically seen in soft colloidal systems. We identify promising avenues for future research that can address current knowledge gaps, which are also highly relevant for the sustainable engineering of advanced bioinspired and biomimetic materials.
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Affiliation(s)
- Vinodkumar Saranathan
- Division of Science, Yale-NUS College, 10 College Avenue West, 138609, Singapore; NUS Nanotechnology and Nanoscience Initiative, National University of Singapore, 117581, Singapore.
| | - Cédric Finet
- Division of Science, Yale-NUS College, 10 College Avenue West, 138609, Singapore
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12
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Inaba M, Chuong CM. Avian Pigment Pattern Formation: Developmental Control of Macro- (Across the Body) and Micro- (Within a Feather) Level of Pigment Patterns. Front Cell Dev Biol 2020; 8:620. [PMID: 32754601 PMCID: PMC7365947 DOI: 10.3389/fcell.2020.00620] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 06/22/2020] [Indexed: 12/13/2022] Open
Abstract
Animal color patterns are of interest to many fields, such as developmental biology, evolutionary biology, ethology, mathematical biology, bio-mimetics, etc. The skin provides easy access to experimentation and analysis enabling the developmental pigment patterning process to be analyzed at the cellular and molecular level. Studies in animals with distinct pigment patterns (such as zebrafish, horse, feline, etc.) have revealed some genetic information underlying color pattern formation. Yet, how the complex pigment patterns in diverse avian species are established remains an open question. Here we summarize recent progress. Avian plumage shows color patterns occurring at different spatial levels. The two main levels are macro- (across the body) and micro- (within a feather) pigment patterns. At the cellular level, colors are mainly produced by melanocytes generating eumelanin (black) and pheomelanin (yellow, orange). These melanin-based patterns are regulated by melanocyte migration, differentiation, cell death, and/or interaction with neighboring skin cells. In addition, non-melanin chemical pigments and structural colors add more colors to the available palette in different cell types or skin regions. We discuss classic and recent tissue transplantation experiments that explore the avian pigment patterning process and some potential molecular mechanisms. We find color patterns can be controlled autonomously by melanocytes but also non-autonomously by dermal cells. Complex plumage color patterns are generated by the combination of these multi-scale patterning mechanisms. These interactions can be further modulated by environmental factors such as sex hormones, which generate striking sexual dimorphic colors in avian integuments and can also be influenced by seasons and aging.
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Affiliation(s)
- Masafumi Inaba
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Cheng-Ming Chuong
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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13
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Eliason CM, Clarke JA. Cassowary gloss and a novel form of structural color in birds. SCIENCE ADVANCES 2020; 6:eaba0187. [PMID: 32426504 PMCID: PMC7220335 DOI: 10.1126/sciadv.aba0187] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 02/13/2020] [Indexed: 06/11/2023]
Abstract
One of the two lineages of extant birds resulting from its deepest split, Palaeognathae, has been reported not to exhibit structural coloration in feathers, affecting inferences of ancestral coloration mechanisms in extant birds. Structural coloration in facial skin and eggshells has been shown in this lineage, but has not been reported in feathers. We present the first evidence for two distinct mechanisms of structural color in palaeognath feathers. One extinct volant clade, Lithornithidae, shows evidence of elongate melanin-containing organelles uniquely associated with glossy/iridescent color, a structural color mechanism found in fossil outgroups and neognath birds. We also demonstrate a structural basis for the exceptional gloss in extant cassowary feathers. We propose gloss as an intermediate phenotype between matte and iridescent plumage, conferred by a thick and smooth feather rachis. Rachis-based structural color has not been previously investigated. The new data illuminate the relationships between avian melanin-based coloration and feather structure.
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Affiliation(s)
- Chad M. Eliason
- Grainger Bioinformatics Center, Field Museum of Natural History, Chicago, IL, USA
- Jackson School of Geosciences and Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Julia A. Clarke
- Jackson School of Geosciences and Integrative Biology, University of Texas at Austin, Austin, TX, USA
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14
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Abstract
Colourful ornaments often communicate salient information to mates, and theory predicts covariance between signal expression and individual quality. This has borne out among pigment-based signals, but the potential for 'honesty' in structural coloration is unresolved. Here, I synthesized the available evidence to test this prediction via meta-analysis and found that, overall, the expression of structurally coloured sexual signals is positively associated with individual quality. The effects varied by the measure of quality, however, with body condition and immune function reliably encoded across taxa, but not age nor parasite resistance. The relationship was apparent for both the colour and brightness of signals and was slightly stronger for iridescent ornaments. These results suggest diverse pathways to the encoding and exchange of information among structural colours while highlighting outstanding questions as to the development, visual ecology and evolution of this striking adornment.
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Affiliation(s)
- Thomas E White
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales 2106, Australia
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15
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Eliason CM, Maia R, Parra JL, Shawkey MD. Signal evolution and morphological complexity in hummingbirds (Aves:
Trochilidae
). Evolution 2020; 74:447-458. [DOI: 10.1111/evo.13893] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 11/11/2019] [Accepted: 11/12/2019] [Indexed: 02/04/2023]
Affiliation(s)
- Chad M. Eliason
- Grainger Bioinformatics Center Field Museum of Natural History Chicago
| | - Rafael Maia
- Grainger Bioinformatics Center Field Museum of Natural History Chicago
| | - Juan L. Parra
- Grupo de Ecología y Evolución de Vertebrados, Instituto de Biología Universidad de Antioquia Medellín Colombia
| | - Matthew D. Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology University of Ghent 9000 Ghent Belgium
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16
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Babarović F, Puttick MN, Zaher M, Learmonth E, Gallimore EJ, Smithwick FM, Mayr G, Vinther J. Characterization of melanosomes involved in the production of non-iridescent structural feather colours and their detection in the fossil record. J R Soc Interface 2019; 16:20180921. [PMID: 31238836 DOI: 10.1098/rsif.2018.0921] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Non-iridescent structural colour in avian feathers is produced by coherent light scattering through quasi-ordered nanocavities in the keratin cortex of the barbs. To absorb unscattered light, melanosomes form a basal layer underneath the nanocavities. It has been shown that throughout Aves, melanosome morphology reflects broad categories of melanin-based coloration, as well as iridescence, allowing identification of palaeocolours in exceptionally preserved fossils. However, no studies have yet investigated the morphology of melanosomes in non-iridescent structural colour. Here, we analyse a wide sample of melanosomes from feathers that express non-iridescent structural colour from a phylogenetically broad range of extant avians to describe their morphology and compare them with other avian melanosome categories. We find that investigated melanosomes are typically wide (approx. 300 nm) and long (approx. 1400 nm), distinct from melanosomes found in black, brown and iridescent feathers, but overlapping significantly with melanosomes from grey feathers. This may suggest a developmental, and perhaps evolutionary, relationship between grey coloration and non-iridescent structural colours. We show that through analyses of fossil melanosomes, melanosomes indicative of non-iridescent structural colour can be predicted in an Eocene stem group roller ( Eocoracias: Coraciiformes) and with phylogenetic comparative methods the likely hue can be surmised. The overlap between melanosomes from grey and non-iridescent structurally coloured feathers complicates their distinction in fossil samples where keratin does not preserve. However, the abundance of grey coloration relative to non-iridescent structural coloration makes the former a more likely occurrence except in phylogenetically bracketed specimens like the specimen of Eocoracias studied here.
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Affiliation(s)
- Frane Babarović
- 1 Department of Animal and Plant Sciences, University of Sheffield , Sheffield S10 2TN , UK.,3 School of Earth Sciences, University of Bristol , Wills Memorial Building, Queen's Road, Bristol BS8 1RJ , UK
| | - Mark N Puttick
- 2 Department of Biology and Biochemistry, University of Bath , Claverton Down, Bath BA2 7AY , UK
| | - Marta Zaher
- 3 School of Earth Sciences, University of Bristol , Wills Memorial Building, Queen's Road, Bristol BS8 1RJ , UK
| | - Elizabeth Learmonth
- 4 School of Biological Sciences , Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TH , UK
| | - Emily-Jane Gallimore
- 4 School of Biological Sciences , Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TH , UK
| | - Fiann M Smithwick
- 3 School of Earth Sciences, University of Bristol , Wills Memorial Building, Queen's Road, Bristol BS8 1RJ , UK
| | - Gerald Mayr
- 5 Senckenberg Research Institute, Section of Ornithology , Senckenberganlage 25, 60325 Frankfurt am Main , Germany
| | - Jakob Vinther
- 3 School of Earth Sciences, University of Bristol , Wills Memorial Building, Queen's Road, Bristol BS8 1RJ , UK.,4 School of Biological Sciences , Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TH , UK
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17
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D'Alba L, Shawkey MD. Melanosomes: Biogenesis, Properties, and Evolution of an Ancient Organelle. Physiol Rev 2019; 99:1-19. [PMID: 30255724 DOI: 10.1152/physrev.00059.2017] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Melanosomes are organelles that produce and store melanin, a widespread biological pigment with a unique suite of properties including high refractive index, semiconducting capabilities, material stiffness, and high fossilization potential. They are involved in numerous critical biological functions in organisms across the tree of life. Individual components such as melanin chemistry and melanosome development have recently been addressed, but a broad synthesis is needed. Here, we review the hierarchical structure, development, functions, and evolution of melanosomes. We highlight variation in melanin chemistry and melanosome morphology and how these may relate to function. For example, we review what is known of the chemical differences between different melanin types (eumelanin, pheomelanin, allomelanin) and whether/how melanosome morphology relates to chemistry and color. We integrate the distribution of melanin across living organisms with what is known from the fossil record and produce hypotheses on its evolution. We suggest that melanin was present in life forms early in evolutionary history and that melanosomes evolved at the origin of organelles. Throughout, we discuss the (sometimes gaping) holes in our knowledge and suggest areas that need particular attention as we move forward in our understanding of these still-mysterious organelles and the materials that they contain.
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Affiliation(s)
- Liliana D'Alba
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent , Ghent , Belgium
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent , Ghent , Belgium
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18
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Airoldi CA, Ferria J, Glover BJ. The cellular and genetic basis of structural colour in plants. CURRENT OPINION IN PLANT BIOLOGY 2019; 47:81-87. [PMID: 30399605 DOI: 10.1016/j.pbi.2018.10.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/04/2018] [Accepted: 10/08/2018] [Indexed: 05/23/2023]
Abstract
While the pathways that produce plant pigments have been well studied for decades, the use by plants of nanoscale structures to produce colour effects has only recently begun to be studied. A variety of plants from across the plant kingdom have been shown to use different mechanism to generate structural colours in tissues as diverse as leaves, flowers and fruits. In this review we explore the cellular mechanisms by which these nanoscale structures are built and discuss the first insights that have been published into the genetic pathways underpinning these traits.
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Affiliation(s)
- Chiara A Airoldi
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
| | - Jordan Ferria
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
| | - Beverley J Glover
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
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19
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Nordén KK, Faber JW, Babarović F, Stubbs TL, Selly T, Schiffbauer JD, Peharec Štefanić P, Mayr G, Smithwick FM, Vinther J. Melanosome diversity and convergence in the evolution of iridescent avian feathers-Implications for paleocolor reconstruction. Evolution 2019; 73:15-27. [PMID: 30411346 PMCID: PMC6587736 DOI: 10.1111/evo.13641] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 10/22/2018] [Indexed: 12/15/2022]
Abstract
Some of the most varied colors in the natural world are created by iridescent nanostructures in bird feathers, formed by layers of melanin-containing melanosomes. The morphology of melanosomes in iridescent feathers is known to vary, but the extent of this diversity, and when it evolved, is unknown. We use scanning electron microscopy to quantify the diversity of melanosome morphology in iridescent feathers from 97 extant bird species, covering 11 orders. In addition, we assess melanosome morphology in two Eocene birds, which are the stem lineages of groups that respectively exhibit hollow and flat melanosomes today. We find that iridescent feathers contain the most varied melanosome morphologies of all types of bird coloration sampled to date. Using our extended dataset, we predict iridescence in an early Eocene trogon (cf. Primotrogon) but not in the early Eocene swift Scaniacypselus, and neither exhibit the derived melanosome morphologies seen in their modern relatives. Our findings confirm that iridescence is a labile trait that has evolved convergently in several lineages extending down to paravian theropods. The dataset provides a framework to detect iridescence with more confidence in fossil taxa based on melanosome morphology.
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Affiliation(s)
- Klara K. Nordén
- School of Earth SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
- Current address: Department of Ecology and Evolutionary BiologyPrinceton UniversityPrincetonNJ08544USA
| | - Jaeike W. Faber
- School of Earth SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
- Current address: Department of Medical BiologyAcademic Medical CenterUniversity of AmsterdamMeibergdreef 151105 AZAmsterdamThe Netherlands
| | - Frane Babarović
- Current address: Department of Animal and Plant SciencesUniversity of SheffieldS10 2TNSheffieldUK
- Department of Biology, Faculty of ScienceUniversity of ZagrebRooseveltov trg 610 000ZagrebCroatia
| | - Thomas L. Stubbs
- School of Earth SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
| | - Tara Selly
- X‐ray Microanalysis Core FacilityUniversity of Missouri101 Geological Sciences BuildingColumbiaMO65211USA
- Department of Geological SciencesUniversity of Missouri101 Geological Sciences BuildingColumbiaMO65211USA
| | - James D. Schiffbauer
- X‐ray Microanalysis Core FacilityUniversity of Missouri101 Geological Sciences BuildingColumbiaMO65211USA
- Department of Geological SciencesUniversity of Missouri101 Geological Sciences BuildingColumbiaMO65211USA
| | - Petra Peharec Štefanić
- Department of Biology, Faculty of ScienceUniversity of ZagrebRooseveltov trg 610 000ZagrebCroatia
| | - Gerald Mayr
- Senckenberg Research Institute FrankfurtSenckenberganlage 2560325FrankfurtGermany
| | - Fiann M. Smithwick
- School of Earth SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
| | - Jakob Vinther
- School of Earth SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
- School of Biological SciencesUniversity of Bristol24 Tyndall AvenueBristolBS8 1TQUK
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20
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Sarpong K, Madliger CL, Harris CM, Love OP, Doucet SM, Bitton PP. Baseline corticosterone does not reflect iridescent plumage traits in female tree swallows. Gen Comp Endocrinol 2019; 270:123-130. [PMID: 30392885 DOI: 10.1016/j.ygcen.2018.10.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 10/03/2018] [Accepted: 10/23/2018] [Indexed: 01/08/2023]
Abstract
The production of high quality secondary sexual traits can be constrained by trade-offs in the allocation of energy and nutrients with other metabolic activities, and is mediated by physiological processes. In birds, the factors influencing male plumage quality have been well studied; however, factors affecting female plumage quality are poorly understood. Furthermore, it remains uncertain which physiological traits mediate the relationship between body condition and ornaments. In this three-year study of after-second-year female tree swallows (Tachycineta bicolor), we investigated (1) the relationship between baseline corticosterone near the end of the brood-rearing period (CORTBR) and feather colour characteristics (hue, saturation, brightness) the following year, and (2) the relationship between baseline corticosterone measured during incubation (CORTI) and brood rearing (CORTBR), and feather colour in the same year. To control for reproductive effort, we included reproductive parameters as covariates in all analyses. In this first study between CORT and the plumage colour characteristics of a species bearing iridescent feathers, we did not find any relationship between CORTBR and the colour of subsequently-produced feathers, nor did we find any relationship between CORT and the colour of feathers displayed during that breeding season. If CORT levels at the end of breeding carry over to influence the immediately subsequent moult period as we expect, our results generally indicate that structural plumage quality may not be as sensitive to circulating CORT levels compared to carotenoid-based colouration. Future studies, particularly those employing experimental manipulations of CORT during moult in species with iridescent traits, are necessary to fully determine the role glucocorticoids play in mediating the quality of secondary sexual characteristics.
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Affiliation(s)
- Keneth Sarpong
- Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
| | - Christine L Madliger
- Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
| | - Christopher M Harris
- Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
| | - Oliver P Love
- Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
| | - Stéphanie M Doucet
- Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
| | - Pierre-Paul Bitton
- Department of Biological Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
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21
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Wilts BD, Saranathan V. A Literal Elytral Rainbow: Tunable Structural Colors Using Single Diamond Biophotonic Crystals in Pachyrrhynchus congestus Weevils. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1802328. [PMID: 30112799 DOI: 10.1002/smll.201802328] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 07/24/2018] [Indexed: 05/21/2023]
Abstract
The brilliant colors of many insects arise from the interference of incident light with complex nanostructured biomaterials that are present in their cuticle. Here, the rainbow-colored spots on the elytra of a snout weevil, Pachyrrhynchus congestus pavonius (Coleoptera: Curculionidae), are investigated using synchrotron small-angle X-ray scattering, scanning electron microscopy, microspectrophotometry, and photonic bandgap modeling. It is shown that the iridescent scales present in the rainbow-hued spots are due to a 3D photonic crystal network of chitin in air with a single diamond (Fd-3m) symmetry. In many insects, different orientations of photonic crystal domains are used to create various hues. In this weevil, however, both the chitin volume fractions as well as the lattice parameters of the biologically self-assembled single diamond nanostructure are varied to achieve the remarkable tuning of the structural colors across the visible light spectrum on a scale-by-scale basis. Uncovering the precise mechanism of color tuning employed by this weevil has important implications for further structural and developmental research on biophotonic nanostructures and may provide fresh impetus for bioinspired and biomimetic multifunctional applications, as synthesis of photonic crystals at visible length scales is currently challenging.
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Affiliation(s)
- Bodo D Wilts
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Vinodkumar Saranathan
- Division of Science, Yale-NUS College, 10 College Avenue West, Singapore, 138609, Singapore
- NUS Nanotechnology and Nanoscience Initiative (NUSNNI-NanoCore), National University of Singapore, Singapore, 117576, Singapore
- Department of Biological Science, National University of Singapore, Singapore, 117543, Singapore
- Lee Kong Chian Natural History Museum, National University of Singapore, Singapore, 117377, Singapore
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22
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Gao G, Xu M, Bai C, Yang Y, Li G, Xu J, Wei Z, Min J, Su G, Zhou X, Guo J, Hao Y, Zhang G, Yang X, Xu X, Widelitz RB, Chuong CM, Zhang C, Yin J, Zuo Y. Comparative genomics and transcriptomics of Chrysolophus provide insights into the evolution of complex plumage coloration. Gigascience 2018; 7:5091803. [PMID: 30192940 PMCID: PMC6204425 DOI: 10.1093/gigascience/giy113] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 08/29/2018] [Indexed: 01/05/2023] Open
Abstract
Background As one of the most recognizable characteristics in birds, plumage color has a high impact on understanding the evolution and mechanisms of coloration. Feather and skin are ideal tissues to explore the genomics and complexity of color patterns in vertebrates. Two species of the genus Chrysolophus, golden pheasant (Chrysolophus pictus) and Lady Amherst's pheasant (Chrysolophus amherstiae), exhibit brilliant colors in their plumage, but with extreme phenotypic differences, making these two species great models to investigate plumage coloration mechanisms in birds. Results We sequenced and assembled a genome of golden pheasant with high coverage and annotated 15,552 protein-coding genes. The genome of Lady Amherst's pheasant is sequenced with low coverage. Based on the feather pigment identification, a series of genomic and transcriptomic comparisons were conducted to investigate the complex features of plumage coloration. By identifying the lineage-specific sequence variations in Chrysolophus and golden pheasant against different backgrounds, we found that four melanogenesis biosynthesis genes and some lipid-related genes might be candidate genomic factors for the evolution of melanin and carotenoid pigmentation, respectively. In addition, a study among 47 birds showed some candidate genes related to carotenoid coloration in a broad range of birds. The transcriptome data further reveal important regulators of the two colorations, particularly one splicing transcript of the microphthalmia-associated transcription factor gene for pheomelanin synthesis. Conclusions Analysis of the golden pheasant and its sister pheasant genomes, as well as comparison with other avian genomes, are helpful to reveal the underlying regulation of their plumage coloration. The present study provides important genomic information and insights for further studies of avian plumage evolution and diversity.
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Affiliation(s)
- Guangqi Gao
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Meng Xu
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Chunling Bai
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Yulan Yang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Guangpeng Li
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China
| | - Junyang Xu
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Zhuying Wei
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Jiumeng Min
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Guanghua Su
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Xianqiang Zhou
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Jun Guo
- College of Life Science, Inner Mongolia Agricultural University, No.306, Zhaowuda Road, Saihan District, Hohhot, Inner Mongolia, 010018
| | - Yu Hao
- College of Life Science, Inner Mongolia Agricultural University, No.306, Zhaowuda Road, Saihan District, Hohhot, Inner Mongolia, 010018
| | - Guiping Zhang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Xukui Yang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Xiaomin Xu
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Randall B Widelitz
- Department of Pathology, Keck School of Medicine, Universit of Southern California, 2011 Zonal Avenue, HMR315B, Los Angeles, CA90033, USA
| | - Cheng-Ming Chuong
- Department of Pathology, Keck School of Medicine, Universit of Southern California, 2011 Zonal Avenue, HMR315B, Los Angeles, CA90033, USA
| | - Chi Zhang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Jun Yin
- College of Life Science, Inner Mongolia Agricultural University, No.306, Zhaowuda Road, Saihan District, Hohhot, Inner Mongolia, 010018
| | - Yongchun Zuo
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
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23
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Hegyi G, Laczi M, Kötél D, Csizmadia T, Lőw P, Rosivall B, Szöllősi E, Török J. Reflectance variation in the blue tit crown in relation to feather structure. ACTA ACUST UNITED AC 2018; 221:jeb.176727. [PMID: 29615523 DOI: 10.1242/jeb.176727] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 03/21/2018] [Indexed: 11/20/2022]
Abstract
Structural plumage colour is one of the most enigmatic sexually selected traits. The information content of structural colour variation is debated, and the heterogeneity of the findings is hard to explain because the proximate background of within-species colour differences is very scarcely studied. We combined measurements of feather macrostructure and nanostructure to explain within-population variability in blue tit crown reflectance. We found that sexual dichromatism in aspects of crown reflectance was explained only by feather macrostructure, whereas nanostructural predictors accounted for some of the age-related differences in reflectance. Moreover, we found that both mean reflectance and spectral shape traits reflected a combination of quantity and regularity aspects in macrostructure and nanostructure. This rich proximate background provides ample scope for reflectance to convey various types of information on individual quality.
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Affiliation(s)
- Gergely Hegyi
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - Miklós Laczi
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary.,The Barn Owl Foundation, Temesvári út 8, H-8744 Orosztony, Hungary
| | - Dóra Kötél
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - Tamás Csizmadia
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - Péter Lőw
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - Balázs Rosivall
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - Eszter Szöllősi
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - János Török
- Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary.,Ecology Research Group of the Hungarian Academy of Sciences, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
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24
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Shawkey MD, Igic B, Rogalla S, Goldenberg J, Clusella-Trullas S, D'Alba L. Beyond colour: consistent variation in near infrared and solar reflectivity in sunbirds (Nectariniidae). Naturwissenschaften 2017; 104:78. [PMID: 28871351 DOI: 10.1007/s00114-017-1499-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 08/15/2017] [Accepted: 08/20/2017] [Indexed: 11/30/2022]
Abstract
The visible spectrum represents a fraction of the sun's radiation, a large portion of which is within the near infrared (NIR). However, wavelengths outside of the visible spectrum that are reflected by coloured tissues have rarely been considered, despite their potential significance to thermal effects. Here, we report the reflectivity from 300 to 2100 nm of differently coloured feathers. We measured reflectivity across the UV-Vis-NIR spectra of different (a) body parts, (b) colour-producing mechanisms and (c) sexes for 252 individuals of 68 sunbird (family: Nectariniidae) species. Breast plumage was the most reflective and cap plumage the least. Female plumage had greater reflectivity than males. Carotenoid-based colours had the greatest reflectivity, followed by non-iridescent and iridescent melanin-based colours. As ordered arrays of melanin-filled organelles (melanosomes) produce iridescent colours, this suggests that nanostructuring may affect reflectance across the spectrum. Our results indicate that differently coloured feathers consistently vary in their thermal, as well as obvious visual, properties.
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Affiliation(s)
- Matthew D Shawkey
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000, Ghent, Belgium.
| | - Branislav Igic
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000, Ghent, Belgium.,Division of Ecology & Evolution, Research School of Biology, Australian National University, Canberra, 2601, ACT, Australia
| | - Svana Rogalla
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000, Ghent, Belgium
| | - Jonathan Goldenberg
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000, Ghent, Belgium
| | - Susana Clusella-Trullas
- Department of Botany and Zoology & Centre for Invasion Biology, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Liliana D'Alba
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, 9000, Ghent, Belgium
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25
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Galván I, García-Campa J, Negro JJ. Complex Plumage Patterns Can Be Produced Only with the Contribution of Melanins. Physiol Biochem Zool 2017; 90:600-604. [DOI: 10.1086/693962] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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26
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Chatelain M, Pessato A, Frantz A, Gasparini J, Leclaire S. Do trace metals influence visual signals? Effects of trace metals on iridescent and melanic feather colouration in the feral pigeon. OIKOS 2017. [DOI: 10.1111/oik.04262] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Marion Chatelain
- Sorbonne Universités, UPMC Univ Paris 06, UPEC, Paris 7, CNRS, INRA, IRD, Inst. d'Ecologie et des Sciences de l'Environnement de Paris; Paris France
- Warsaw Univ., Center of New Technologies, S. Banacha 2c; PL-02-097 Warsaw Poland
| | - Anaϊs Pessato
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS; Montpellier France
| | - Adrien Frantz
- Sorbonne Universités, UPMC Univ Paris 06, UPEC, Paris 7, CNRS, INRA, IRD, Inst. d'Ecologie et des Sciences de l'Environnement de Paris; Paris France
| | - Julien Gasparini
- Sorbonne Universités, UPMC Univ Paris 06, UPEC, Paris 7, CNRS, INRA, IRD, Inst. d'Ecologie et des Sciences de l'Environnement de Paris; Paris France
| | - Sarah Leclaire
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS; Montpellier France
- Laboratoire Evolution and Diversité Biologique, UMR 5174 (CNRS, Université Paul Sabatier, ENFA); Toulouse France
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27
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Quantitative characterization and comparative study of feather melanosome internal morphology using surface analysis. Micron 2016; 82:17-24. [PMID: 26760226 DOI: 10.1016/j.micron.2015.12.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 12/20/2015] [Accepted: 12/20/2015] [Indexed: 11/21/2022]
Abstract
A successful feather development implies in a precise orchestration of cells in the follicle, which culminates in one of the most complex epidermal structures in nature. Melanocytes contribute to the final structure by delivering melanosomes to the barb and barbule cells. Disturbance to the tissue during the feather growth can damage the final structure. Here, melanosomes seen in an unusual outgrowth on the barb cortex of a flight feather are reported and compared to commonly observed melanosomes embedded in the cortex. Transmission Electron Microscopy in scanning-transmission mode (STEM) generated images coupled with secondary electron detection. The two classes of melanosomes were registered on images combining transmitted and secondary electron signals. Image processing allowed surface analyses of roughness and texture of the internal morphology of these organelles. Results showed that the two classes of melanosomes are significantly distinct internally, indicating that different physiological processes up to feather maturation could have occurred. Surface analysis methods are not regularly used in cell biology studies, but here it is shown that it has great potential for microscopic image analysis, which could add robust information to studies of cell biology events.
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28
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Vinther J. Fossil melanosomes or bacteria? A wealth of findings favours melanosomes: Melanin fossilises relatively readily, bacteria rarely, hence the need for clarification in the debate over the identity of microbodies in fossil animal specimens. Bioessays 2015; 38:220-5. [PMID: 26692172 DOI: 10.1002/bies.201500168] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The discovery of fossil melanosomes has resulted in a wealth of research over the last 7 years, notably the reconstruction of colour in dinosaurs and fossil mammals. In spite of these discoveries some authors persist in arguing that the observed microbodies could represent preserved bacteria. They contend that bacteria fossilise easily and everywhere, which means that one can never be certain that a microbody is a melanosome without an extraordinary burden of evidence. However, this critique mischaracterises the morphological and structural evidence for interpreting microbodies as fossil melanosomes, and hence the basis for using them in reconstructing prehistoric colours. The claims for bacterial omnipresence in the fossil record are themselves not supported, thus tipping the scales strongly towards melanosomes in the bacteria-versus-melanosome controversy.
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Affiliation(s)
- Jakob Vinther
- Schools of Earth Sciences and Biological Sciences, Life Sciences Building University of Bristol, Bristol, United Kingdom
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29
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Abstract
Dopamine-melanin nanospheres are promising materials for photoprotection, structural coloration, and thermoregulation due to their unusual optical and chemical properties. Here, we report the experimental parameters which influence size of dopamine-melanin nanospheres and uniformity. Dopamine precursors are oxidatively polymerized in basic aqueous medium. Therefore, concentration of hydroxide ions significantly influences reaction rate and size of nanospheres. To investigate the effect of hydroxide ions, we adjust three different parameters which affect pH of medium: concentration of sodium hydroxide and dopamine hydrochloride, and reaction temperature. At constant temperature, concentration of hydroxide ions is linearly proportional to initial reaction rates which determine the number of nuclei for nanosphere growth. Temperature alters not only initial reaction rate but also diffusivity of molecules, leading to deviation from the relation between the reaction rate and the number of nuclei. The diameter of dopamine-melanin nanospheres can be readily controlled in a range of 80-490nm through adjusting concentration of dopamine precursor, while maintaining uniform-size distribution and dispersion stability. The synthesized nanospheres are analyzed to confirm the chemical structure, which is composed of approximately 6 indole units. Moreover, surface and chemical properties of the nanospheres are characterized to provide valuable information for surface modification and application.
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Affiliation(s)
- Soojeong Cho
- BK21+ program, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Shin-Hyun Kim
- BK21+ program, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea.
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30
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Eliason CM, Maia R, Shawkey MD. Modular color evolution facilitated by a complex nanostructure in birds. Evolution 2015; 69:357-67. [DOI: 10.1111/evo.12575] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 11/11/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Chad M. Eliason
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325
- Current address: Department of Integrative Biology; University of Texas; Austin Texas 78712
| | - Rafael Maia
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325
| | - Matthew D. Shawkey
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325
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31
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Shawkey MD, D'Alba L, Xiao M, Schutte M, Buchholz R. Ontogeny of an iridescent nanostructure composed of hollow melanosomes. J Morphol 2014; 276:378-84. [DOI: 10.1002/jmor.20347] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 10/20/2014] [Accepted: 11/09/2014] [Indexed: 01/05/2023]
Affiliation(s)
- Matthew D. Shawkey
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325-3908 USA
| | - Liliana D'Alba
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325-3908 USA
| | - Ming Xiao
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325-3908 USA
- Department of Polymer Science; The University of Akron; Akron Ohio 44325-3909 USA
| | - Matthew Schutte
- Department of Biology and Integrated Bioscience Program; The University of Akron; Akron Ohio 44325-3908 USA
| | - Richard Buchholz
- Department of Biology; University of Mississippi; University; Mississippi 38677-1848 USA
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32
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Xiao M, Dhinojwala A, Shawkey M. Nanostructural basis of rainbow-like iridescence in common bronzewing Phaps chalcoptera feathers. OPTICS EXPRESS 2014; 22:14625-14636. [PMID: 24977558 DOI: 10.1364/oe.22.014625] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Structural colors are common in nature. Generally single feathers or other integuments contain only one structural color, but those of the common bronzewing display a consistent color gradient from blue to red (462-647 nm) over the proximo-distal length of individual barbs. We used optical microscopy and macro- and micro-spectrophotometry to characterize this color gradient, and transmission electron microscopy to investigate the nanostructure. Combining optical modeling and experimental results, we demonstrate that the rainbow-like iridescence is caused by multilayer interference from organized arrays of melanosome rods in a keratin matrix and that the color gradient results from subtle shifts in both diameter and spacing of melanosome rods. This result illustrates tight developmental control feathers and may provide inspiration for the design of multi-colored coatings or fibers.
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33
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Eliason CM, Shawkey MD. Antireflection-enhanced color by a natural graded refractive index (GRIN) structure. OPTICS EXPRESS 2014; 22 Suppl 3:A642-A650. [PMID: 24922372 DOI: 10.1364/oe.22.00a642] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nanostructured materials like graded refractive index (GRIN) structures in moth eyes have inspired the design of novel antireflective coatings. Such structures are more flexible than uniform coatings, but applications have been mainly limited to broadband antireflection in solar cells and LEDs. Here we show that cylindrical pigment granules in two bird species (Polyplectron bicalcaratum and Patagioenas fasciata) form a GRIN that suppresses interference and expands the range of colors produced by a multilayer. These results demonstrate that a GRIN structure can function like a pigment (i.e. through selective, independent wavelength blocking) to generate unique colors and may inspire the design of novel antireflective and structurally colored coatings.
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34
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Eliason CM, Bitton PP, Shawkey MD. How hollow melanosomes affect iridescent colour production in birds. Proc Biol Sci 2013; 280:20131505. [PMID: 23902909 DOI: 10.1098/rspb.2013.1505] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Developmental constraints and trade-offs can limit diversity, but organisms have repeatedly evolved morphological innovations that overcome these limits by expanding the range and functionality of traits. Iridescent colours in birds are commonly produced by melanin-containing organelles (melanosomes) organized into nanostructured arrays within feather barbules. Variation in array type (e.g. multilayers and photonic crystals, PCs) is known to have remarkable effects on plumage colour, but the optical consequences of variation in melanosome shape remain poorly understood. Here, we used a combination of spectrophotometric, experimental and theoretical methods to test how melanosome hollowness--a morphological innovation largely restricted to birds--affects feather colour. Optical analyses of hexagonal close-packed arrays of hollow melanosomes in two species, wild turkeys (Meleagris gallopavo) and violet-backed starlings (Cinnyricinclus leucogaster), indicated that they function as two-dimensional PCs. Incorporation of a larger dataset and optical modelling showed that, compared with solid melanosomes, hollow melanosomes allow birds to produce distinct colours with the same energetically favourable, close-packed configurations. These data suggest that a morphological novelty has, at least in part, allowed birds to achieve their vast morphological and colour diversity.
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Affiliation(s)
- Chad M Eliason
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH, USA.
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35
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36
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Roulin A, Ducrest AL. Genetics of colouration in birds. Semin Cell Dev Biol 2013; 24:594-608. [PMID: 23665152 DOI: 10.1016/j.semcdb.2013.05.005] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Revised: 04/19/2013] [Accepted: 05/01/2013] [Indexed: 01/01/2023]
Abstract
Establishing the links between phenotype and genotype is of great importance for resolving key questions about the evolution, maintenance and adaptive function of phenotypic variation. Bird colouration is one of the most studied systems to investigate the role of natural and sexual selection in the evolution of phenotypic diversity. Given the recent advances in molecular tools that allow discovering genetic polymorphisms and measuring gene and protein expression levels, it is timely to review the literature on the genetics of bird colouration. The present study shows that melanin-based colour phenotypes are often associated with mutations at melanogenic genes. Differences in melanin-based colouration are caused by switches of eumelanin to pheomelanin production or by changes in feather keratin structure, melanoblast migration and differentiation, as well as melanosome structure. Similar associations with other types of colourations are difficult to establish, because our knowledge about the molecular genetics of carotenoid-based and structural colouration is quasi inexistent. This discrepancy stems from the fact that only melanin-based colouration shows pronounced heritability estimates, i.e. the resemblance between related individuals is usually mainly explained by genetic factors. In contrast, the expression of carotenoid-based colouration is phenotypically plastic with a high sensitivity to variation in environmental conditions. It therefore appears that melanin-based colour traits are prime systems to understand the genetic basis of phenotypic variation. In this context, birds have a great potential to bring us to new frontiers where many exciting discoveries will be made on the genetics of phenotypic traits, such as colouration. In this context, a major goal of our review is to suggest a number of exciting future avenues.
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Affiliation(s)
- Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.
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37
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Walker LK, Stevens M, Karadaş F, Kilner RM, Ewen JG. A window on the past: male ornamental plumage reveals the quality of their early-life environment. Proc Biol Sci 2013; 280:20122852. [PMID: 23407833 DOI: 10.1098/rspb.2012.2852] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
It is well established that the expression of many ornamental traits is dependent on the current condition of the bearer. However, conditions experienced in early life are also known to be important for an individual's subsequent fitness and therefore, directly or indirectly, for the fitness of their mate. Specifically, a recent hypothesis suggests that sexually selected traits might be sensitive to conditions experienced during early-life development and thereby function as honest indicators of developmental history. Whether this applies to colourful male plumage, however, is largely unknown. We tested this idea with a field experiment by manipulating neonatal nutrition in a sexually dichromatic passerine, the hihi (Notymystis cincta). We found that carotenoid supplementation increased nestling plasma carotenoid concentration, which was in turn correlated with increased yellow saturation in male breeding plumage after moulting. We also found that the post-moult luminance (lightness) of the white ear-tufts tended to be reduced in males that had received an all-round nutritional supplement as nestlings. Black breeding plumage was not affected by neonatal nutritional treatment. Although the mechanisms that generate colourful plumage are evidently diverse, our results show that at least some parts of this display are accurate indicators of environmental conditions during development.
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Affiliation(s)
- Leila K Walker
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
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38
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Meadows MG, Roudybush TE, McGraw KJ. Dietary protein level affects iridescent coloration in Anna's hummingbirds, Calypte anna. J Exp Biol 2012; 215:2742-50. [PMID: 22837446 DOI: 10.1242/jeb.069351] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Many animal displays involve colorful ornamental traits that signal an individual's quality as a mate or rival. Brilliant iridescent ornaments are common, but little is currently known about their production cost and signaling value. One potential cost of colorful ornaments is the acquisition of limited dietary resources that may be involved, directly or indirectly, in their production. Protein, the primary component of bird feathers and of many nanostructural components of iridescent traits, is naturally restricted in hummingbird diets (comprised mostly of sugars), suggesting that iridescent coloration may be especially challenging to produce in these animals. In this study, we experimentally investigated the effect of dietary protein availability during molt on iridescent color expression in male Anna's hummingbirds (Calypte anna). We fed captive birds either a 6% (high) or a 3% (low) protein diet and stimulated molt by plucking half the gorget and crown ornaments on each bird as well as the non-ornamental iridescent green tail feathers. We found that birds receiving more protein grew significantly more colorful crown feathers (higher red chroma and redder hue) than those fed the low-protein diet. Diet did not affect gorget coloration, but regrowth of feathers in captivity affected both gorget and crown coloration. Additionally, birds on the high-protein diet grew yellower (higher hue) green tail feathers than birds on the low-protein diet. These results indicate that iridescent ornamental feathers are sensitive to diet quality and may serve as honest signals of nutrition to mates or rivals. Further, because both ornamental and non-ornamental iridescent coloration were affected by conditions during their growth, iridescent color in these birds appears to be generally condition dependent.
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Affiliation(s)
- Melissa G Meadows
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA.
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39
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Maia R, Brasileiro L, Lacava RV, Macedo RH. Social environment affects acquisition and color of structural nuptial plumage in a sexually dimorphic tropical passerine. PLoS One 2012; 7:e47501. [PMID: 23082172 PMCID: PMC3474847 DOI: 10.1371/journal.pone.0047501] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Accepted: 09/14/2012] [Indexed: 11/25/2022] Open
Abstract
Structural colors result from the physical interaction of light with organic materials of differing refractive indexes organized at nanoscale dimensions to produce significant interference effects. Because color properties emerge from these finely organized nanostructures, the production of structural coloration could respond to environmental factors and be developmentally more plastic than expected, functioning as an indicator of individual quality. However, there are many unknown factors concerning the function and mechanisms regulating structural coloration, especially relative to social environment. We hypothesized that social environment, in the form of competitive settings, can influence the developmental pathways involving production of feather structural coloration. We experimentally assessed the impact of social environment upon body condition, molt and spectral properties of two types of structural color that compose the nuptial plumage in blue-black grassquits: black iridescent plumage and white underwing patches. We manipulated male social environment during nine months by keeping individuals in three treatments: (1) pairs; (2) all-male groups; and (3) male-female mixed groups. All morphological characters and spectral plumage measures varied significantly through time, but only acquisition of nuptial plumage coverage and nuptial plumage color were influenced by social environment. Compared with males in the paired treatment, those in treatments with multiple males molted into nuptial plumage faster and earlier, and their plumage was more UV-purple-shifted. Our results provide experimental evidence that social context strongly influences development and expression of structural plumage. These results emphasize the importance of long-term experimental studies to identify the phenotypic consequences of social dynamics relative to ornament expression.
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Affiliation(s)
- Rafael Maia
- Programa de Pós-Graduação em Ecologia, Universidade de Brasília, Brasília, DF, Brazil
- Department of Biology, Integrated Bioscience Program, The University of Akron, Akron, Ohio, United States of America
| | - Luiza Brasileiro
- Programa de Pós-Graduação em Ecologia, Universidade de Brasília, Brasília, DF, Brazil
- Laboratório de Comportamento Animal, Departamento de Zoologia, Universidade de Brasília, Brasília, DF, Brazil
| | - Roberto V. Lacava
- Programa de Pós-Graduação em Ecologia, Universidade de Brasília, Brasília, DF, Brazil
- Laboratório de Comportamento Animal, Departamento de Zoologia, Universidade de Brasília, Brasília, DF, Brazil
| | - Regina H. Macedo
- Laboratório de Comportamento Animal, Departamento de Zoologia, Universidade de Brasília, Brasília, DF, Brazil
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40
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Eliason CM, Shawkey MD. A photonic heterostructure produces diverse iridescent colours in duck wing patches. J R Soc Interface 2012; 9:2279-89. [PMID: 22491981 DOI: 10.1098/rsif.2012.0118] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The colours of birds are diverse but limited relative to the colours they can perceive. This mismatch may be partially caused by the properties of their colour-production mechanisms. Aside from pigments, several classes of highly ordered nanostructures (thin films, amorphous three-dimensional arrays) can produce a range of colours. However, the variability of any single nanostructural class has rarely been explored. Dabbling ducks are a speciose clade with substantial interspecific variation in the iridescent coloration of their wing patches (specula). Here, we use electron microscopy, spectrophotometry, polarization and refractive index-matching experiments, and optical modelling to examine these colours. We show that, in all species examined, speculum colour is produced by a photonic heterostructure consisting of both a single thin-film of keratin and a two-dimensional hexagonal lattice of melanosomes in feather barbules. Although the range of possible variations of this heterostructure is theoretically broad, only relatively close-packed, energetically stable variants producing more saturated colours were observed, suggesting that ducks are either physically constrained to these configurations or are under selection for the colours that they produce. These data thus reveal a previously undescribed biophotonic structure and suggest that both physical variability and constraints within single nanostructural classes may help explain the broader patterns of colour across Aves.
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Affiliation(s)
- Chad M Eliason
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH, USA.
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41
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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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