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Janas K, Gaweł P, Łatkiewicz A, Lutyk D, Gustafsson L, Cichoń M, Drobniak SM. Sexual dichromatism, size dimorphism, and microscale anatomy of white wing stripe in blue tits. Curr Zool 2021; 67:585-596. [PMID: 34805536 PMCID: PMC8599086 DOI: 10.1093/cz/zoab011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/25/2021] [Indexed: 11/12/2022] Open
Abstract
Achromatic patches are a common element of plumage patterns in many bird species and there is growing body of evidence that in many avian taxa they can play a signaling role in mate choice. Although the blue tit Cyanistes caeruleus is a well-established model species in the studies on coloration, its white wing patch has never been examined in the context of sex-specific trait expression. In this exploratory study, we examined sexual size dimorphism and dichromatism of greater covert’s dots creating white wing patch and analyzed its correlations with current body condition and crown coloration—a trait with established role in sexual selection. Further, we qualitatively analyzed microstructural barb morphology underlying covert’s coloration. We found significant sexual dimorphism in the dot size independent of covert size and sexual dichromatism in both white dot and blue outer covert’s vane spectral characteristics. Internal structure of covert barbs within the white dot was similar to the one found in barbs from the blue part that is, with a medullary area consisting of dead keratinocytes containing channel-type ß-keratin spongy nanostructure and centrally located air cavities. However, it lacked melanosomes which was the main observed difference. Importantly, UV chroma of covert’s blue vane was positively correlated with crown UV chroma and current condition (the latter only in males), which should be a premise for further research on the signal function of the wing stripe.
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Affiliation(s)
- Katarzyna Janas
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30- 387, Kraków, Poland
| | - Paulina Gaweł
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30- 387, Kraków, Poland
| | - Anna Łatkiewicz
- Institute of Geological Sciences, Faculty of Geography and Geology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Dorota Lutyk
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30- 387, Kraków, Poland
| | - Lars Gustafsson
- Department of Animal Ecology/Ecology and Genetics, Uppsala University, Norbyvägen 18 D, 752 36, Uppsala, Sweden
| | - Mariusz Cichoń
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30- 387, Kraków, Poland
| | - Szymon M Drobniak
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30- 387, Kraków, Poland.,School of Biological, Environmental and Earth Sciences, University of New South Wales, Biological Sciences Building (D26), Kensington Sydney, NSW 2052 Australia
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2
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Angelier F. Pigeons in the sun: Thermal constraints of eumelanic plumage in the rock pigeon (Columba livia). J Therm Biol 2020; 90:102601. [PMID: 32479396 DOI: 10.1016/j.jtherbio.2020.102601] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/27/2020] [Accepted: 04/13/2020] [Indexed: 12/28/2022]
Abstract
In wild vertebrates, several species exhibit eumelanic color polymorphism with the coexistence of dark and light morphs. The maintenance of such polymorphism suggests the existence of a selective balance between the morphs and a large body of literature has reported the costs and benefits of darker plumage coloration in birds. Among them, it has been suggested that melanin and dark plumage could entail high energetic costs especially under hot and sunny climates. However, to my knowledge, the thermal constraints of sun exposure have rarely been studied in polymorphic species. Here, we tested the impact of eumelanic plumage coloration on plumage and body temperatures, and evaporative cooling behavior in the polymorphic rock pigeon (Columbia livia). We experimentally exposed light and dark pigeons to direct sun radiation for 1 h while a few birds were maintained in the shade as controls. We found that sun exposure was associated with increased plumage temperature, and this effect was greater for darker pigeons. In addition, we found that sun exposure was also associated with higher cloacal temperature but for dark pigeons only. Finally, light and dark pigeons were more likely to show cooling evaporative behavior when exposed to sun and as their cloacal temperature increases. Altogether, these results suggest that darker pigeons may have a lower ability to cope with heat and solar radiations and that dark plumage can be associated with thermal costs in this polymorphic species.
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Affiliation(s)
- Frédéric Angelier
- Centre d'Etudes Biologiques de Chizé, CNRS, La Rochelle Université, UMR, 7372, Villiers en Bois, France.
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3
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Javůrková VG, Enbody ED, Kreisinger J, Chmel K, Mrázek J, Karubian J. Plumage iridescence is associated with distinct feather microbiota in a tropical passerine. Sci Rep 2019; 9:12921. [PMID: 31501471 PMCID: PMC6733896 DOI: 10.1038/s41598-019-49220-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 08/21/2019] [Indexed: 12/27/2022] Open
Abstract
Birds present a stunning diversity of plumage colors that have long fascinated evolutionary ecologists. Although plumage coloration is often linked to sexual selection, it may impact a number of physiological processes, including microbial resistance. At present, the degree to which differences between pigment-based vs. structural plumage coloration may affect the feather microbiota remains unanswered. Using quantitative PCR and DGGE profiling, we investigated feather microbial load, diversity and community structure among two allopatric subspecies of White-shouldered Fairywren, Malurus alboscapulatus that vary in expression of melanin-based vs. structural plumage coloration. We found that microbial load tended to be lower and feather microbial diversity was significantly higher in the plumage of black iridescent males, compared to black matte females and brown individuals. Moreover, black iridescent males had distinct feather microbial communities compared to black matte females and brown individuals. We suggest that distinctive nanostructure properties of iridescent male feathers or different investment in preening influence feather microbiota community composition and load. This study is the first to point to structural plumage coloration as a factor that may significantly regulate feather microbiota. Future work might explore fitness consequences and the role of microorganisms in the evolution of avian sexual dichromatism, with particular reference to iridescence.
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Affiliation(s)
- Veronika Gvoždíková Javůrková
- Faculty of Agrobiology, Food and Natural Resources, Department of Animal Science, Czech University of Life Sciences, Kamýcká 129, 165 00, Prague, Suchdol, Czech Republic. .,Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 65, Brno, Czech Republic.
| | - Erik D Enbody
- Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA, USA
| | - Jakub Kreisinger
- Faculty of Science, Department of Zoology, Charles University, Viničná 7, 128 44, Prague, Czech Republic
| | - Kryštof Chmel
- Faculty of Science, Department of Zoology, Charles University, Viničná 7, 128 44, Prague, Czech Republic.,Faculty of Science, Department of Zoology, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic
| | - Jakub Mrázek
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Vídeňská 1083, 160 00, Prague-Krč, Czech Republic
| | - Jordan Karubian
- Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA, USA
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Parolini M, Iacobuzio R, Bassano B, Pennati R, Saino N. Melanin-Based Skin Coloration Predicts Antioxidant Capacity in the Brown Trout (Salmo trutta). Physiol Biochem Zool 2018; 91:1026-1035. [PMID: 30084732 DOI: 10.1086/699522] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In many vertebrate species, individuals exhibit large variation in the degree of melanin-based coloration on their body. Dark and pale individuals differ in diverse physiological and behavioral traits, suggesting that melanic coloration may reveal individual quality. However, research into the relationships between physiological and skin traits, in terms of melanin-based skin coloration, in wild fish is scant. Our correlative study aimed at investigating the relationships between physiology and melanin-based coloration of the skin of free-living brown trout (Salmo trutta Linnaeus, 1758). We scrutinized the relationships between body condition (body mass and Fulton's K condition factor), oxidative status (plasma total antioxidant capacity and amount of pro-oxidant molecules), and the degree of melanin-based skin coloration assessed by digital photography and image analysis. We found heavier fish to be, on average, darker colored than paler conspecifics. Moreover, a significant covariation between plasma total antioxidant capacity and melanic coloration was noted. Our findings suggest that the melanin-based coloration of brown trout serves as a signal to communicate a better antioxidant defense to conspecifics.
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Gaillard M, Scriba MF, Roulin A. Melanism is related to behavioural lateralization in nestling barn owls. Behav Processes 2017; 140:139-143. [PMID: 28483429 DOI: 10.1016/j.beproc.2017.05.006] [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: 03/13/2017] [Revised: 05/04/2017] [Accepted: 05/04/2017] [Indexed: 12/27/2022]
Abstract
Behavioural laterality is a commonly observed phenomenon in many species suggesting there might be an advantage of using dominantly one side over the other for certain tasks. Indeed, lateralized individuals were often shown to be more successful in cognitive tasks compared to non-lateralized conspecifics. However, stressed individuals are also often, but not always, more strongly lateralized. Because barn owl (Tyto alba) females displaying larger black spots on the tip of their ventral feathers produce offspring that are more resistant to a variety of environmental stressful factors, we examined whether laterality is associated with melanin-based coloration. We recorded whether nestlings use more often the right or left foot to scratch their body and whether they preen more often one side of the body or the other using their bills. We found that the strength of lateralization of preening and scratching was less pronounced in individuals born from heavily spotted mothers. This result might be explained by plumage-related variation in the ability to resist stressful rearing conditions.
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Affiliation(s)
| | - Madeleine F Scriba
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland.
| | - Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
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Moreno-Rueda G. Preen oil and bird fitness: a critical review of the evidence. Biol Rev Camb Philos Soc 2017; 92:2131-2143. [PMID: 28231637 DOI: 10.1111/brv.12324] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 01/23/2017] [Accepted: 01/27/2017] [Indexed: 11/28/2022]
Abstract
The uropygial gland is a holocrine complex exclusive to birds that produces an oleaginous secretion (preen oil) whose function is still debated. Herein, I examine critically the evidence for the many hypotheses of potential functions of this gland. The main conclusion is that our understanding of this gland is still in its infancy. Even for functions that are considered valid by most researchers, real evidence is scarce. Although it seems clear that preen oil contributes to plumage maintenance, we do not know whether this is due to a role in reducing mechanical abrasion or in reducing feather degradation by keratinophilic organisms. Evidence for a function against pathogenic bacteria is mixed, as preen oil has been demonstrated to act against bacteria in vitro, but not in vivo. Nor is it clear whether preen oil can combat pathogenic bacteria on eggshells to improve hatching success. Studies on the effect of preen oil against dermatophytes are very scarce and there is no evidence of a function against chewing lice. It seems clear, however, that preen oil improves waterproofing, but it is unclear whether this acts by creating a hydrophobic layer or simply by improving plumage structure. Several hypotheses proposed for the function of preen oil have been poorly studied, such as reduction of drag in flight. Similarly, we do not know whether preen oil functions as repellent against predators or parasites, makes birds unpalatable, or functions to camouflage birds with ambient odours. On the other hand, a growing body of work shows the important implications of volatiles in preen oil with regard to social communication in birds. Moreover, preen oil clearly alters plumage colouration. Finally, studies examining the impact of preen oil on fitness are lacking, and the costs or limitations of preen-oil production also remain poorly known. The uropygial gland appears to have several non-mutually exclusive functions in birds, and thus is likely to be subject to several selective pressures. Therefore, future studies should consider how the inevitable trade-offs among different functions drive the evolution of uropygial gland secretions.
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Affiliation(s)
- Gregorio Moreno-Rueda
- Departamento de Zoología, Facultad de Ciencias, Universidad de Granada, E-18071, Granada, Spain
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Seddon RJ, Hews DK. Phenotypic correlates of melanization in two Sceloporus occidentalis (Phrynosomatidae) populations: Behavior, androgens, stress reactivity, and ectoparasites. Physiol Behav 2016; 163:70-80. [PMID: 27137079 DOI: 10.1016/j.physbeh.2016.04.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 04/04/2016] [Accepted: 04/22/2016] [Indexed: 11/19/2022]
Abstract
Mechanisms underlying production of animal coloration can affect key traits besides coloration. Melanin, and molecules regulating melanin, can directly and indirectly affect other phenotypic traits including aggression, stress-reactivity, and immune function. We studied correlation of melanization with these other traits, comparing within- and between-population differences of adult male western fence lizards, Sceloporus occidentalis. We compared one high- and one low-elevation population in California where individuals are increasingly darker at higher elevations, working during comparable periods of the breeding season at each site (first egg clutch). We measured agonistic behaviors of free-ranging males in response to staged territorial intrusions (STIs). In other sets of males we measured baseline testosterone and corticosterone levels, and hormonal-reactivity to a stress handling paradigm. We counted ectoparasite loads for all males. There were no significant associations between individual variation in melanization and individual variation in any of the variables measured. However, analysis of behavior from the STIs revealed that males in the darker high-elevation population responded with more aggressive behavior compared to males in the lighter low-elevation population. Males in the low-elevation population had significantly higher mean baseline testosterone, but the two populations did not differ in adrenal function (baseline corticosterone or corticosterone after 1-h confinement stress). Males in the darker high-elevation population had higher mean mite loads compared to males in the lighter population. This array of phenotypic differences between the two populations, and the absence of trait associations when assessing individual variation, do not parallel the patterns in other vertebrates. We describe potential differences in selective regimes that could produce these different patterns across vertebrates. These data suggest that hormonal pleiotropy does not constrain phenotypic variation.
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Affiliation(s)
- Ryan J Seddon
- Department of Biology, Indiana State University, Terre Haute, IN 47809, USA.
| | - Diana K Hews
- Department of Biology, Indiana State University, Terre Haute, IN 47809, USA
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Walsh J, Shriver WG, Olsen BJ, Kovach AI. Differential introgression and the maintenance of species boundaries in an advanced generation avian hybrid zone. BMC Evol Biol 2016; 16:65. [PMID: 27000833 PMCID: PMC4802838 DOI: 10.1186/s12862-016-0635-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/10/2016] [Indexed: 12/31/2022] Open
Abstract
Background Evolutionary processes, including selection and differential fitness, shape the introgression of genetic material across a hybrid zone, resulting in the exchange of some genes but not others. Differential introgression of molecular or phenotypic markers can thus provide insight into factors contributing to reproductive isolation. We characterized patterns of genetic variation across a hybrid zone between two tidal marsh birds, Saltmarsh (Ammodramus caudacutus) and Nelson’s (A. nelsoni) sparrows (n = 286), and compared patterns of introgression among multiple genetic markers and phenotypic traits. Results Geographic and genomic cline analyses revealed variable patterns of introgression among marker types. Most markers exhibited gradual clines and indicated that introgression exceeds the spatial extent of the previously documented hybrid zone. We found steeper clines, indicating strong selection for loci associated with traits related to tidal marsh adaptations, including for a marker linked to a gene region associated with metabolic functions, including an osmotic regulatory pathway, as well as for a marker related to melanin-based pigmentation, supporting an adaptive role of darker plumage (salt marsh melanism) in tidal marshes. Narrow clines at mitochondrial and sex-linked markers also offer support for Haldane’s rule. We detected patterns of asymmetrical introgression toward A. caudacutus, which may be driven by differences in mating strategy or differences in population density between the two species. Conclusions Our findings offer insight into the dynamics of a hybrid zone traversing a unique environmental gradient and provide evidence for a role of ecological divergence in the maintenance of pure species boundaries despite ongoing gene flow. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0635-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jennifer Walsh
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, USA. .,Cornell Lab of Ornithology, Cornell University, Ithaca, NY, USA.
| | - W Gregory Shriver
- Department of Entomology and Wildlife Ecology, University of Delaware, Newark, DE, USA
| | - Brian J Olsen
- School of Biology and Ecology, University of Maine, Orono, ME, USA
| | - Adrienne I Kovach
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, USA
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Roulin A, Mangels J, Wakamatsu K, Bachmann T. Sexually dimorphic melanin-based colour polymorphism, feather melanin content, and wing feather structure in the barn owl (Tyto alba). Biol J Linn Soc Lond 2013. [DOI: 10.1111/bij.12078] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexandre Roulin
- Department of Ecology and Evolution; Université de Lausanne; Lausanne; Switzerland
| | - Jule Mangels
- Institute for Fluid Mechanics and Aerodynamics; Technische Universität Darmstadt; Darmstadt; Germany
| | - Kazumasa Wakamatsu
- Department of Chemistry; School of Health Sciences; Fujita Health University; Toyoake; Aichi; Japan
| | - Thomas Bachmann
- Institute for Fluid Mechanics and Aerodynamics; Technische Universität Darmstadt; Darmstadt; Germany
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Moreno-Rueda G, Hoi H. Female house sparrows prefer big males with a large white wing bar and fewer feather holes caused by chewing lice. Behav Ecol 2011. [DOI: 10.1093/beheco/arr182] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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MORENO-RUEDA G. Experimental test of a trade-off between moult and immune response in house sparrows Passer domesticus. J Evol Biol 2010; 23:2229-2237. [DOI: 10.1111/j.1420-9101.2010.02090.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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12
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Griggio M, Hoi H, Pilastro A. Plumage maintenance affects ultraviolet colour and female preference in the budgerigar. Behav Processes 2010; 84:739-44. [DOI: 10.1016/j.beproc.2010.05.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 04/14/2010] [Accepted: 05/04/2010] [Indexed: 12/01/2022]
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Tanaka K. Does the Thermal Advantage of Melanism Produce Size Differences in Color-dimorphic Snakes? Zoolog Sci 2009; 26:698-703. [DOI: 10.2108/zsj.26.698] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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VERGARA PABLO, FARGALLO JUANA, MARTÍNEZ-PADILLA JESÚS, LEMUS JESÚSA. Inter-annual variation and information content of melanin-based coloration in female Eurasian kestrels. Biol J Linn Soc Lond 2009. [DOI: 10.1111/j.1095-8312.2009.01263.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Roulin A. Melanin-based coloration covaries with ovary size in an age-specific manner in the barn owl. Naturwissenschaften 2009; 96:1177-84. [PMID: 19575175 DOI: 10.1007/s00114-009-0579-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Revised: 05/18/2009] [Accepted: 05/20/2009] [Indexed: 11/28/2022]
Abstract
While the adaptive function of black eumelanin-based coloration is relatively well known, the function of reddish-brown pheomelanin-based coloration is still unclear. Only a few studies have shown or suggested that the degree of reddish-brownness is associated with predator-prey relationships, reproductive parameters, growth rate and immunity. To gain insight into the physiological correlates of melanin-based coloration, I collected barn owl (Tyto alba) cadavers and examined the covariation between this colour trait and ovary size, an organ that increases in size before reproduction. A relationship is expected because melanin-based coloration often co-varies with sexual activity. The results showed that reddish-brown juveniles had larger ovaries than whiter juveniles particularly in individuals in poor condition and outside the breeding season, while in birds older than 2 years lightly coloured females had larger ovaries than reddish-brown conspecifics. As barn owls become less reddish-brown between the first and second year of age, the present study suggests that reddish-brown pheomelanic and whitish colorations are associated with juvenile- and adult-specific adaptations, respectively.
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Affiliation(s)
- Alexandre Roulin
- Department of Ecology and Evolution, Biophore, University of Lausanne, Lausanne, Switzerland.
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Wedekind C, Jacob A, Evanno G, Nusslé S, Müller R. Viability of brown trout embryos positively linked to melanin-based but negatively to carotenoid-based colours of their fathers. Proc Biol Sci 2008; 275:1737-44. [PMID: 18445560 PMCID: PMC2453293 DOI: 10.1098/rspb.2008.0072] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
‘Good-genes’ models of sexual selection predict significant additive genetic variation for fitness-correlated traits within populations to be revealed by phenotypic traits. To test this prediction, we sampled brown trout (Salmo trutta) from their natural spawning place, analysed their carotenoid-based red and melanin-based dark skin colours and tested whether these colours can be used to predict offspring viability. We produced half-sib families by in vitro fertilization, reared the resulting embryos under standardized conditions, released the hatchlings into a streamlet and identified the surviving juveniles 20 months later with microsatellite markers. Embryo viability was revealed by the sires' dark pigmentation: darker males sired more viable offspring. However, the sires' red coloration correlated negatively with embryo survival. Our study demonstrates that genetic variation for fitness-correlated traits is revealed by male colour traits in our study population, but contrary to predictions from other studies, intense red colours do not signal good genes.
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Affiliation(s)
- Claus Wedekind
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland.
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Piault R, Gasparini J, Bize P, Paulet M, McGraw KJ, Roulin A. Experimental support for the makeup hypothesis in nestling tawny owls (Strix aluco). Behav Ecol 2008. [DOI: 10.1093/beheco/arm152] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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