Climate underpins continent‐wide patterns of carotenoid‐based feather colour consistent with Gloger's observations

Journal of Animal Ecology, Journal Year: 2025, Volume and Issue: unknown

Published: March 25, 2025

Animal coloration has long been predicted to vary across geographic and climatic gradients in accordance with a long-standing ecogeographical rule. But further his widely supported predictions that melanin pigmentation increases towards the Equator, Gloger observed reds yellows are more vivid warm regions thus prevalent at lower latitudes, prediction by Görnitz, who suggested these colours would be intense areas higher rainfall. Yet, studies of associations between geography or climate carotenoid-based plumage test observations continental scale scarce. Here, we investigated extent which yellow red feather colour varies according hypotheses Pogoniulus tinkerbirds distributions sub-Saharan Africa. We tested first for along latitudinal elevational gradients, then factors rainfall temperature may underpin variation on scales. find evidence consistent Görnitz's saturated warmer hues latitudes were primarily attributed relationship underpart By contrast, forecrown colour, trait previously associated sexual selection, had complex association climate, hue rainfall, but intensity showing contrasting patterns latitude. highlight nature coloration, suggesting although environmental affect abundance carotenoid availability, is also influenced other selective pressures.

Language: Английский

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A genomic basis of vocal rhythm in birds

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 23, 2024

Abstract Vocal rhythm plays a fundamental role in sexual selection and species recognition birds, but little is known of its genetic basis due to the confounding effect vocal learning model systems. Uncovering could facilitate identifying genes potentially important speciation. Here we investigate genomic underpinnings non-learning Pogoniulus tinkerbirds using 135 individual whole genomes distributed across southern African hybrid zone. We find speed associated with two that are also affect human speech, Neurexin-1 Coenzyme Q8A. Models leveraging ancestry reveal these candidate loci impact rhythmic stability, trait linked motor performance which an indicator quality. Character displacement stability suggests possible reinforcement against hybridization, supported by evidence asymmetric assortative mating producing faster, more stable rhythms. Because omnipresent animal communication, identified here may shape birds other vertebrates.

Language: Английский

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Avian colouration in a polluted world: a meta‐analysis

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2024, Volume and Issue: 99(4), P. 1261 - 1277

Published: March 17, 2024

ABSTRACT Brilliant, diverse colour ornaments of birds were one the crucial cues that led Darwin to idea sexual selection. Although avian colouration plays many functions, including concealment, thermoregulation, or advertisement as a distasteful prey, quality‐signalling role in selection has attracted most research attention. Sexually selected are thought be more susceptible external stressors than naturally traits, and such, they might used test for environmental quality. For this reason, last two decades have seen numerous studies on impact anthropogenic pollution expression various traits. Herein, we provide first meta‐analytical summary these results examine whether there is an interaction between mechanism production (carotenoid‐based, melanin‐based structural) type factor (categorised heavy metals, persistent organic pollutants, urbanisation, other). Following assumption heightened condition dependence under selection, also expected magnitude effect sizes higher males. The overall size was close significance negative, supporting general detrimental pollutants colouration. In contrast expectations, no types colour‐producing mechanisms. Yet significant differences sensitivity mechanisms, with carotenoid‐based being affected by disturbances. Moreover, observed tendency towards We identified publication gap structural colouration, which, compared pigment‐based remains markedly understudied should thus prioritised future research. Finally, call unification methods quantification ecological ensure comparability among studies.

Language: Английский

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Decoding ladybird's colours: structural mechanisms of colour production and pigment modulation.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 21, 2025

Abstract This study investigates the mechanisms underlying colour production in family Coccinellidae, focusing on two model species: A. bipunctata (L) and C. quatuordecimguttata . In this family, colours have traditionally been attributed primarily to pigments such as carotenoids melanins. We propose an alternative perspective, considering elytra integrated optical medium whose properties result from both its architectural design of constituent materials, including matrix pigments. present work, several methods were used, ranging electron microscopies, light-based techniques, LC-HRMS analyses. Through local pigment analyses, microstructural examination elytra, modelling interaction with light, we show that, while are central patterning contribute colour, overall also results one or more physical that may operate simultaneously. light these results, assume complex diverse colouration Coccinellidae can only be elucidated by interplay elytron cuticle.

Language: Английский

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Inbreeding and competitor’s genetic relatedness affect dynamic male color-ornament expression in a cichlid fish

The American Naturalist, Journal Year: 2025, Volume and Issue: unknown

Published: April 16, 2025

Language: Английский

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Subtle, but perceptible, sexual dichromatism and disassortative mating based on plumage reflectance in Black Terns (Chlidonias niger)

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 12, 2024

In birds, sexual selection on plumage often leads to dichromatism and male ornamentation. However, even in drab species with no obvious dichromatism, both sexes may still use for mate choice. A previous study found weak size dimorphism North American Black Terns (Chlidonias niger surinamensis), but assortative mating based morphology. the relevance of variation choice is yet untested. Here, using reflectance spectrometry avian visual modeling revealed that Tern males females exhibited a subtle significant difference brightness (males darker). Importantly, achromatic contrast between should be perceptible during Moreover, there was evidence disassortative color, not brightness: more black saturated birds paired gray unsaturated birds. There relationship color or body mass. This finding suggests signals unrelated condition relevant The pattern unexpected, potential benefits choosing dissimilar from oneself are discussed. highlights importance considering system when studying elusive human observers.

Language: Английский

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Carotenoid skin ornaments as flexible indicators of male foraging behavior in a marine predator: Variation among Mexican colonies of brown booby (Sula leucogaster)

Marine Biology, Journal Year: 2024, Volume and Issue: 171(5)

Published: April 24, 2024

Abstract Carotenoid-dependent ornaments can reflect animals’ diet and foraging behaviors. However, this association should be spatially flexible variable among populations to account for geographic variation in optimal We tested hypothesis using of a marine predator (the brown booby, Sula leucogaster ) that forage across gradient ocean depth near the Gulf California. Specifically, we quantified green chroma two skin traits (foot gular color) their relationship location males, as measured via global positioning system tracking stable carbon isotope analysis blood plasma. Our three focal colonies varied which attributes were linked carotenoid-rich ornaments. For skin, our data showed shift from benthic prey-green shallow waters north pelagic deepest south. Mean trip duration distance site coast also predicted coloration some colonies. Finally, booby trait versus was associated with metrics. Overall, results indicate male quality foraging–information may help females select mates who are adapted local conditions therefore, likely provide better parental care. More broadly, stress diet-dependent closely environments cannot assume or ornament signal content ubiquitous within species, even when appear similar populations.

Language: Английский

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Feather Carotenoids of the American Redstart (Setophaga Ruticilla) Across Age and Sex Classes and the Reliability of Standard Color Metrics to Capture Pigment Variation

Published: Jan. 1, 2024

Plumage ornaments act as important sexual signals, though the extent to which these honest signals—and physiological mechanisms that maintain honesty—remain poorly understood. We studied pigmentary basis of tail color in American Redstart (Setophaga ruticilla), a species songbird with dichromatism and delayed plumage maturation; younger males resemble females, only replacing their yellow feathers for bright orange ones after first breeding season. The rectrices females young older largely contain same pigments, but vastly different proportions. Whereas primarily lutein, 3'-dehydro-lutein canary-xanthophylls, those red 4-keto-carotenoids. relatively uncommon hue results from presence lutein predominance α-doradexanthin 4-keto-carotenoid, pigment shortened chain conjugated double bonds compared keto-carotenoids commonly found feathers. Since coloration redstart combination yellow, orange, this is system where slight adjustments types carotenoids deposited could drastically alter hue. Factors either work against achieving most oxidized state or maintained through stabilizing selection favored color. metrics Carotenoid Chroma, Visible Hue, λR50 tetrahedral θ best captured differences concentration make-up, are recommended future spectrophotometric studies carotenoid-based traits.

Language: Английский

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Feather carotenoids of the American Redstart (Setophaga ruticilla) across age and sex classes and the reliability of standard color metrics to capture pigment variation

Comparative Biochemistry and Physiology Part B Biochemistry and Molecular Biology, Journal Year: 2024, Volume and Issue: 275, P. 111027 - 111027

Published: Aug. 29, 2024

Language: Английский

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Alternative Pathways for Carotenoid Transformation Could Reduce Colour Production Efficiency in Wild Common Crossbills (Loxia Curvirostra)

Published: Jan. 1, 2024

ABSTRACT: In many vertebrates, dietary yellow carotenoids are enzymatically transformed into 4C-ketocarotenoid pigments, leading to conspicuous red colourations. These colourations may evolve as signals of individual quality under sexual or social selection. To signals, they must transmit reliable information benefiting both the receiver and signaler. Some argue that reliability 4C-ketocarotenoid-based is ensured by tight link between cell (mitochondrial) metabolism, which supposedly involved in transforming carotenoids. We studied how a range covary feathers blood plasma large number (n > 140) wild male common crossbills (Loxia curvirostra). Plumage redness was mainly due 3-hydroxy-echinenone (3HOE). Two other 4C-ketocarotenoids, although less abundant (astaxanthin canthaxanthin), could have contributed feather colour redder pigments. This demonstrated for astaxanthin but not canthaxanthin, whose levels were uncorrelated colouration. Moreover, moulting carried more 3HOE than non-moulting ones, canthaxanthin did differ. Canthaxanthin formed from echinenone, product β-carotene ketolation. Echinenone ketolated hydroxylated produce 3HOE, respectively. birds, positively correlated its precursor, negatively levels. Redder birds also had lower values. An imbalance activity (or level) ketolases (e.g. CYP2J19) hydroxylases (unknown) explain production. hypothesise colouration indicate birds' ability avoid inefficiencies complex enzymatic pathways.

Language: Английский

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