Tanager

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 930 Experts worldwide ranked by ideXlab platform

Manfred Gahr - One of the best experts on this subject based on the ideXlab platform.

  • seasonality at the equator isotope signatures and hormonal correlates of molt phenology in a non migratory amazonian songbird
    Frontiers in Zoology, 2018
    Co-Authors: Rene Quispe, Elizabeth Yohannes, Manfred Gahr
    Abstract:

    Birds, across their annual cycle, progress through sequences of life-history stages such as reproduction and molt. The mechanisms that control annual avian itineraries involve endocrine responses triggered by seasonal environmental factors, including changes in resource availability and/or photoperiod. However, at equatorial latitudes birds are exposed to different degrees of seasonality, and the mechanisms underlying phenology of birds near the equator remain less explored. We studied the silver-beaked Tanager, an endemic Amazonian songbird, from an equatorial lowland population. Remarkably, in this species, song behavior has been shown to be seasonally aligned to minimal changes in day length near the equator. Here, we aimed to further explore the phenology of silver-beaked Tanagers by assessing shifts of food sources utilization as potential ultimate factors. We measured triple isotopic tracers of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) in blood and feathers of birds throughout a whole year. In addition, we assessed the degree of seasonality in the molting activity, in relation to circulating levels of corticosterone, as well as to testosterone as a proxy of the reproductive condition of males. There was important seasonal variation of δ34S values in relation to rainfall patterns and changes in estuarine water composition. Despite the seasonal rainfall, we found no substantial variation in the foraging ecology of birds over seasons. This was accompanied by uniform levels of corticosterone throughout the year, probably associated with the absence of drastic seasonal resource shortages. Even so, silver-beaked Tanagers showed a marked seasonal molting schedule, which was related to variation in the circulating levels of both corticosterone and testosterone. These findings suggest that foraging niche is not life history stage-dependent in silver-beaked Tanagers, and highlight rainfall as an important environmental cue for bird phenology. Our stable isotope results encourage further studies addressing the influence of estuarine water dynamics on bird timing. In addition, the results suggest a primary role of steroid hormones in regulating seasonal life history stages under the absence of a marked photoperiod. Contrary to what might be expected for a tropical songbird, our physiological data in silver-beaked Tanagers do not support reproduction-molt overlapping.

  • Seasonality at the equator: isotope signatures and hormonal correlates of molt phenology in a non-migratory Amazonian songbird
    'Springer Science and Business Media LLC', 2018
    Co-Authors: Rene Quispe, Elizabeth Yohannes, Manfred Gahr
    Abstract:

    Abstract Background Birds, across their annual cycle, progress through sequences of life-history stages such as reproduction and molt. The mechanisms that control annual avian itineraries involve endocrine responses triggered by seasonal environmental factors, including changes in resource availability and/or photoperiod. However, at equatorial latitudes birds are exposed to different degrees of seasonality, and the mechanisms underlying phenology of birds near the equator remain less explored. We studied the silver-beaked Tanager, an endemic Amazonian songbird, from an equatorial lowland population. Remarkably, in this species, song behavior has been shown to be seasonally aligned to minimal changes in day length near the equator. Here, we aimed to further explore the phenology of silver-beaked Tanagers by assessing shifts of food sources utilization as potential ultimate factors. We measured triple isotopic tracers of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) in blood and feathers of birds throughout a whole year. In addition, we assessed the degree of seasonality in the molting activity, in relation to circulating levels of corticosterone, as well as to testosterone as a proxy of the reproductive condition of males. Results There was important seasonal variation of δ34S values in relation to rainfall patterns and changes in estuarine water composition. Despite the seasonal rainfall, we found no substantial variation in the foraging ecology of birds over seasons. This was accompanied by uniform levels of corticosterone throughout the year, probably associated with the absence of drastic seasonal resource shortages. Even so, silver-beaked Tanagers showed a marked seasonal molting schedule, which was related to variation in the circulating levels of both corticosterone and testosterone. Conclusions These findings suggest that foraging niche is not life history stage-dependent in silver-beaked Tanagers, and highlight rainfall as an important environmental cue for bird phenology. Our stable isotope results encourage further studies addressing the influence of estuarine water dynamics on bird timing. In addition, the results suggest a primary role of steroid hormones in regulating seasonal life history stages under the absence of a marked photoperiod. Contrary to what might be expected for a tropical songbird, our physiological data in silver-beaked Tanagers do not support reproduction-molt overlapping

Amy Forsyth - One of the best experts on this subject based on the ideXlab platform.

Nicholas A Mason - One of the best experts on this subject based on the ideXlab platform.

  • a genus level classification of the family thraupidae class aves order passeriformes
    Zootaxa, 2016
    Co-Authors: Kevin J Burns, Philip Unitt, Nicholas A Mason
    Abstract:

    The Tanagers (Thraupidae) are a major component of the Neotropical avifauna, and vary in plumage colors, behaviors, morphologies, and ecologies. Globally, they represent nearly 4% of all avian species and are the largest family of songbirds. However, many currently used Tanager genera are not monophyletic, based on analyses of molecular data that have accumulated over the past 25 years. Current genus-level classifications of Tanagers have not been revised according to newly documented relationships of Tanagers for various reasons: 1) the lack of a comprehensive phylogeny, 2) reluctance to lump existing genera into larger groups, and 3) the lack of available names for newly defined smaller groups. Here, we present two alternative classifications based on a newly published comprehensive phylogeny of Tanagers. One of these classifications uses existing generic names, but defines them broadly. The other, which we advocate and follow here, provides new generic names for more narrowly defined groups. Under the latter, we propose eleven new genera (Asemospiza, Islerothraupis, Maschalethraupis, Chrysocorypha, Kleinothraupis, Castanozoster, Ephippiospingus, Chionodacryon, Pseudosaltator, Poecilostreptus, Stilpnia), and resurrect several generic names to form monophyletic taxa. Either of these classifications would allow taxonomic authorities to reconcile classification with current understanding of Tanager phylogenetic relationships. Having a more phylogenetically accurate classification for Tanagers will facilitate the study and conservation of this important Neotropical radiation of songbirds.

  • phylogenetics and diversification of Tanagers passeriformes thraupidae the largest radiation of neotropical songbirds
    Molecular Phylogenetics and Evolution, 2014
    Co-Authors: Kevin J Burns, Nicholas A Mason, Allison J Shultz, Pascal O Title, Keith F Barker, John Klicka, Scott M Lanyon
    Abstract:

    Thraupidae is the second largest family of birds and represents about 4% of all avian species and 12% of the Neotropical avifauna. Species in this family display a wide range of plumage colors and patterns, foraging behaviors, vocalizations, ecotypes, and habitat preferences. The lack of a complete phylogeny for Tanagers has hindered the study of this evolutionary diversity. Here, we present a comprehensive, species-level phylogeny for Tanagers using six molecular markers. Our analyses identified 13 major clades of Tanagers that we designate as subfamilies. In addition, two species are recognized as distinct branches on the Tanager tree. Our topologies disagree in many places with previous estimates of relationships within Tanagers, and many long-recognized genera are not monophyletic in our analyses. Our trees identify several cases of convergent evolution in plumage ornaments and bill morphology, and two cases of social mimicry. The phylogeny produced by this study provides a robust framework for studying macroevolutionary patterns and character evolution. We use our new phylogeny to study diversification processes, and find that Tanagers show a background model of exponentially declining diversification rates. Thus, the evolution of Tanagers began with an initial burst of diversification followed by a rate slowdown. In addition to this background model, two later, clade-specific rate shifts are supported, one increase for Darwin’s finches and another increase for some species of Sporophila. The rate of diversification within these two groups is exceptional, even when compared to the overall rapid rate of diversification found within Tanagers. This study provides the first robust assessment of diversification rates for the Darwin’s finches in the context of the larger group within which they evolved.

Rene Quispe - One of the best experts on this subject based on the ideXlab platform.

  • seasonality at the equator isotope signatures and hormonal correlates of molt phenology in a non migratory amazonian songbird
    Frontiers in Zoology, 2018
    Co-Authors: Rene Quispe, Elizabeth Yohannes, Manfred Gahr
    Abstract:

    Birds, across their annual cycle, progress through sequences of life-history stages such as reproduction and molt. The mechanisms that control annual avian itineraries involve endocrine responses triggered by seasonal environmental factors, including changes in resource availability and/or photoperiod. However, at equatorial latitudes birds are exposed to different degrees of seasonality, and the mechanisms underlying phenology of birds near the equator remain less explored. We studied the silver-beaked Tanager, an endemic Amazonian songbird, from an equatorial lowland population. Remarkably, in this species, song behavior has been shown to be seasonally aligned to minimal changes in day length near the equator. Here, we aimed to further explore the phenology of silver-beaked Tanagers by assessing shifts of food sources utilization as potential ultimate factors. We measured triple isotopic tracers of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) in blood and feathers of birds throughout a whole year. In addition, we assessed the degree of seasonality in the molting activity, in relation to circulating levels of corticosterone, as well as to testosterone as a proxy of the reproductive condition of males. There was important seasonal variation of δ34S values in relation to rainfall patterns and changes in estuarine water composition. Despite the seasonal rainfall, we found no substantial variation in the foraging ecology of birds over seasons. This was accompanied by uniform levels of corticosterone throughout the year, probably associated with the absence of drastic seasonal resource shortages. Even so, silver-beaked Tanagers showed a marked seasonal molting schedule, which was related to variation in the circulating levels of both corticosterone and testosterone. These findings suggest that foraging niche is not life history stage-dependent in silver-beaked Tanagers, and highlight rainfall as an important environmental cue for bird phenology. Our stable isotope results encourage further studies addressing the influence of estuarine water dynamics on bird timing. In addition, the results suggest a primary role of steroid hormones in regulating seasonal life history stages under the absence of a marked photoperiod. Contrary to what might be expected for a tropical songbird, our physiological data in silver-beaked Tanagers do not support reproduction-molt overlapping.

  • Seasonality at the equator: isotope signatures and hormonal correlates of molt phenology in a non-migratory Amazonian songbird
    'Springer Science and Business Media LLC', 2018
    Co-Authors: Rene Quispe, Elizabeth Yohannes, Manfred Gahr
    Abstract:

    Abstract Background Birds, across their annual cycle, progress through sequences of life-history stages such as reproduction and molt. The mechanisms that control annual avian itineraries involve endocrine responses triggered by seasonal environmental factors, including changes in resource availability and/or photoperiod. However, at equatorial latitudes birds are exposed to different degrees of seasonality, and the mechanisms underlying phenology of birds near the equator remain less explored. We studied the silver-beaked Tanager, an endemic Amazonian songbird, from an equatorial lowland population. Remarkably, in this species, song behavior has been shown to be seasonally aligned to minimal changes in day length near the equator. Here, we aimed to further explore the phenology of silver-beaked Tanagers by assessing shifts of food sources utilization as potential ultimate factors. We measured triple isotopic tracers of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) in blood and feathers of birds throughout a whole year. In addition, we assessed the degree of seasonality in the molting activity, in relation to circulating levels of corticosterone, as well as to testosterone as a proxy of the reproductive condition of males. Results There was important seasonal variation of δ34S values in relation to rainfall patterns and changes in estuarine water composition. Despite the seasonal rainfall, we found no substantial variation in the foraging ecology of birds over seasons. This was accompanied by uniform levels of corticosterone throughout the year, probably associated with the absence of drastic seasonal resource shortages. Even so, silver-beaked Tanagers showed a marked seasonal molting schedule, which was related to variation in the circulating levels of both corticosterone and testosterone. Conclusions These findings suggest that foraging niche is not life history stage-dependent in silver-beaked Tanagers, and highlight rainfall as an important environmental cue for bird phenology. Our stable isotope results encourage further studies addressing the influence of estuarine water dynamics on bird timing. In addition, the results suggest a primary role of steroid hormones in regulating seasonal life history stages under the absence of a marked photoperiod. Contrary to what might be expected for a tropical songbird, our physiological data in silver-beaked Tanagers do not support reproduction-molt overlapping

Kevin J Burns - One of the best experts on this subject based on the ideXlab platform.

  • a new genus and species of Tanager passeriformes thraupidae from the lower yungas of western bolivia and southern peru
    Ornithology, 2021
    Co-Authors: Daniel F Lane, Miguel Aponte Justiniano, Ryan S Terrill, Frank E Rheindt, Luke B Klicka, Gary H Rosenberg, Jonathan C Schmitt, Kevin J Burns
    Abstract:

    We describe a colorful and distinctive new species of Tanager from the lower slopes of the Andes of southeastern Peru and western Bolivia. The species was first noted from southeastern Peru in 2000, but little of its natural history was uncovered until the 2011 discovery of a breeding population in deciduous forest in an intermontane valley, the Machariapo valley, in Bolivia. This species appears to be an intratropical migrant, breeding in deciduous forest during the rainy season (November–March) and spending the dry season dispersed along the lower slopes of the Andes, apparently favoring Guadua bamboo-dominated habitats in both seasons. Phylogenetic evidence suggests this Tanager is embedded within a clade of thraupids that includes Ramphocelus, Coryphospingus, Loriotus, Tachyphonus, and related genera in the subfamily Tachyphoninae. Within this subfamily, the new species falls in a clade with two monotypic genera, Eucometis penicillata (Gray-headed Tanager) and Trichothraupis melanops (Black-goggled Tanager). There is strong support for a sister relationship between the new Tanager and T. melanops, but because all three species in this clade are highly distinctive phenotypically, we propose erecting a new genus and species name for the new Tanager. LAY SUMMARY We discovered a new species of Tanager, from the foothills of the Andes mountains in Peru and Bolivia, which we name the Inti Tanager. The name “Inti” is the Quechua (a language indigenous to the region) word that means “sun,” referring to the bright yellow color of the bird. Unlike most new bird species discovered recently, which typically differ only subtly from their closest relatives, this species is so different in appearance and genetics that we also described a new genus just for it. The Tanager family, to which the new species belongs, is one of the largest bird families in the world (with about 377 species), restricted almost entirely to the American tropics and including many beautifully colorful species. We uncovered a surprising piece of natural history about the Inti Tanager: it migrates from its breeding grounds in a little-explored valley in Bolivia to “winter” along the lower slopes of the Andes in Peru. Such migration within the tropics is rare within the Tanagers. That this unique, bright yellow bird could have gone unnoticed by ornithologists until recently attests to the remoteness of the areas where it lives and to the importance of continued biological surveys off-the-grid in South America.

  • a genus level classification of the family thraupidae class aves order passeriformes
    Zootaxa, 2016
    Co-Authors: Kevin J Burns, Philip Unitt, Nicholas A Mason
    Abstract:

    The Tanagers (Thraupidae) are a major component of the Neotropical avifauna, and vary in plumage colors, behaviors, morphologies, and ecologies. Globally, they represent nearly 4% of all avian species and are the largest family of songbirds. However, many currently used Tanager genera are not monophyletic, based on analyses of molecular data that have accumulated over the past 25 years. Current genus-level classifications of Tanagers have not been revised according to newly documented relationships of Tanagers for various reasons: 1) the lack of a comprehensive phylogeny, 2) reluctance to lump existing genera into larger groups, and 3) the lack of available names for newly defined smaller groups. Here, we present two alternative classifications based on a newly published comprehensive phylogeny of Tanagers. One of these classifications uses existing generic names, but defines them broadly. The other, which we advocate and follow here, provides new generic names for more narrowly defined groups. Under the latter, we propose eleven new genera (Asemospiza, Islerothraupis, Maschalethraupis, Chrysocorypha, Kleinothraupis, Castanozoster, Ephippiospingus, Chionodacryon, Pseudosaltator, Poecilostreptus, Stilpnia), and resurrect several generic names to form monophyletic taxa. Either of these classifications would allow taxonomic authorities to reconcile classification with current understanding of Tanager phylogenetic relationships. Having a more phylogenetically accurate classification for Tanagers will facilitate the study and conservation of this important Neotropical radiation of songbirds.

  • phylogenetics and diversification of Tanagers passeriformes thraupidae the largest radiation of neotropical songbirds
    Molecular Phylogenetics and Evolution, 2014
    Co-Authors: Kevin J Burns, Nicholas A Mason, Allison J Shultz, Pascal O Title, Keith F Barker, John Klicka, Scott M Lanyon
    Abstract:

    Thraupidae is the second largest family of birds and represents about 4% of all avian species and 12% of the Neotropical avifauna. Species in this family display a wide range of plumage colors and patterns, foraging behaviors, vocalizations, ecotypes, and habitat preferences. The lack of a complete phylogeny for Tanagers has hindered the study of this evolutionary diversity. Here, we present a comprehensive, species-level phylogeny for Tanagers using six molecular markers. Our analyses identified 13 major clades of Tanagers that we designate as subfamilies. In addition, two species are recognized as distinct branches on the Tanager tree. Our topologies disagree in many places with previous estimates of relationships within Tanagers, and many long-recognized genera are not monophyletic in our analyses. Our trees identify several cases of convergent evolution in plumage ornaments and bill morphology, and two cases of social mimicry. The phylogeny produced by this study provides a robust framework for studying macroevolutionary patterns and character evolution. We use our new phylogeny to study diversification processes, and find that Tanagers show a background model of exponentially declining diversification rates. Thus, the evolution of Tanagers began with an initial burst of diversification followed by a rate slowdown. In addition to this background model, two later, clade-specific rate shifts are supported, one increase for Darwin’s finches and another increase for some species of Sporophila. The rate of diversification within these two groups is exceptional, even when compared to the overall rapid rate of diversification found within Tanagers. This study provides the first robust assessment of diversification rates for the Darwin’s finches in the context of the larger group within which they evolved.

Tanager - 15 days free trial to Access Experts & Abstracts