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Gerald Mayr - One of the best experts on this subject based on the ideXlab platform.
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the alleged early miocene auk petralca austriaca is a loon aves Gaviiformes restudy of a controversial fossil bird
Historical Biology, 2018Co-Authors: Ursula B Gohlich, Gerald MayrAbstract:AbstractWe restudy the holotype specimen of the alleged fossil auk Petralca austriaca from early Miocene marine deposits of the Austrian locality Pucking, which was considered the earliest European representative of Alcidae (auks). The specimen is a partial skeleton consisting mainly of wing bones on two slabs. A recent re-preparation yielded new data on the skeletal morphology of Petralca, which allow more detailed comparisons with auks and loons. Our study shows that the taxon is clearly distinguished from auks in various skeletal features and can be confidently identified as a loon (Gaviiformes). Petralca resembles Colymboides in overall morphology of the wing bones, and clearly is a stem group representative of Gaviiformes. However, some features indicate that it is more closely related to the crown group taxon Gavia than to the stem group taxa Colymboides and Colymbiculus. Unusually thick bone walls of the limb bones indicate well-developed diving capabilities for Petralca austriaca.
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middle eocene pelagornithidae and Gaviiformes aves from the ukrainian paratethys
Palaeontology, 2011Co-Authors: Gerald Mayr, Evgenij ZvonokAbstract:: We describe avian remains from Novopskov, a new middle Eocene marine locality in Ukraine. The fossils constitute the most substantial collection of Palaeogene bird bones from Eastern Europe and contribute to a better knowledge of the Paratethyan seabird fauna. Most of the specimens belong to Pelagornithidae (bony-toothed birds), and two species of very different size can be distinguished. The larger of these is tentatively referred to Dasornis sp., the smaller to Odontopteryx toliapica. The specimens include skeletal elements that were not described for Palaeogene bony-toothed birds and document previously unknown morphological differences between Palaeogene and Neogene Pelagornithidae. It is argued that the purported crane Eobalearica tugarinovi, from the middle Eocene of Kyrgyzstan, is probably also a bony-toothed bird. A new genus and species of small Gaviiformes, Colymbiculus udovinchenkoi, is described, which is the earliest fossil record of a loon from Europe, preceding the next oldest specimens by more than 10 myr. The Ukrainian fossils document profound differences between middle Eocene and extant marine avifaunas of Europe, and whereas the middle Eocene Paratethyan avifauna appears to have been similar to that of the North Sea with regard to pelagornithid diversity, the absence of prophaethontids and relative abundance of Gaviiformes may indicate faunistic differences concerning the remaining seabirds.
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A small loon and a new species of large owl from the Rupelian of Belgium (Aves: Gaviiformes, Strigiformes)
Paläontologische Zeitschrift, 2009Co-Authors: Gerald MayrAbstract:Die unteroligozäne Boom Formation in Belgien lieferte zahlreiche Vogelüberreste aus dem Stratotyp der Rupel-Stufe, von denen die meisten allerdings bis jetzt unbearbeitet blieben. Hier beschreibe ich einen kleinen Seetaucher (Gaviiformes) und eine neue Art einer großen Eule (Strigiformes), die jeweils durch mehrere Knochen eines einzelnen Individuums repräsentiert sind. Der Seetaucher, von dem Flügel- und Schultergürtelelemente erhalten sind, wird zu Colymboides (?) metzleri gestellt, einer Art, die bisher nur von einem Teilskelett aus dem Rupelton Deutschlands bekannt war. Die Eule basiert auf einem Tarsometatarsus und einem distalen Tibiotarsus und wird als neue Art, Selenornis steendorpensis , beschrieben. Sie stellt den umfangreichsten Fossilnachweis des Taxons Selenornis dar, welches bisher nur von einem distalen Tibiotarsus von einem unbekannten Horizont der Spaltfüllungen des Quercy im südwestlichem Frankreich bekannt war. Es wird ausgeführt, dass es Unterschiede bezüglich der taxonomischen Zusammensetzung der unteroligozänen Avifaunen von Nord- und Südeuropa gibt, welche möglicherweise tatsächliche tiergeographische Tatsachen infolge eines unterschiedlichen Klimas und einer unterschiedlichen Vegetation widerspiegeln. The early Oligocene Boom Formation in Belgium yielded many avian remains from the Rupelian unit-stratotype, most of which have remained unstudied so far. Here, I describe a small loon (Gaviiformes) and a new species of large owl (Strigiformes) that are represented by associated bones of a single individual each. The loon, of which wing and pectoral girdle bones are preserved, is assigned to Colymboides (?) metzleri , a species previously known from a partial skeleton from the Rupelian of Germany. The owl is based on a tarsometatarsus and distal tibiotarsus and described as a new species, Selenornis steendorpensis . It constitutes the most substantial fossil record of the taxon Selenornis , which was before known from a distal tibiotarsus from an unknown horizon of the Quercy fissure fillings in southwestern France. It is detailed that there are differences in the higher level taxonomic composition of the known early Oligocene avifaunas of northern and southern Europe, which may reflect true zoogeographic facts owing to a different climate and vegetation.
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A small loon and a new species of large owl from the Rupelian of Belgium (Aves: Gaviiformes, Strigiformes)
Paläontologische Zeitschrift, 2009Co-Authors: Gerald MayrAbstract:The early Oligocene Boom Formation in Belgium yielded many avian remains from the Rupelian unit-stratotype, most of which have remained unstudied so far. Here, I describe a small loon (Gaviiformes) and a new species of large owl (Strigiformes) that are represented by associated bones of a single individual each. The loon, of which wing and pectoral girdle bones are preserved, is assigned to Colymboides (?) metzleri, a species previously known from a partial skeleton from the Rupelian of Germany. The owl is based on a tarsometatarsus and distal tibiotarsus and described as a new species, Selenornis steendorpensis. It constitutes the most substantial fossil record of the taxon Selenornis, which was before known from a distal tibiotarsus from an unknown horizon of the Quercy fissure fillings in southwestern France. It is detailed that there are differences in the higher level taxonomic composition of the known early Oligocene avifaunas of northern and southern Europe, which may reflect true zoogeographic facts owing to a different climate and vegetation.
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A Loon Leg (Aves, Gaviidae) with Crocodilian Tooth from the Late Oligocene of Germany
Waterbirds, 2009Co-Authors: Gerald Mayr, Markus PoschmannAbstract:Abstract. The first late Oligocene fossil record of a loon (Gaviiformes) is described from the lacustrine deposits of the German locality Enspel. The specimen is an isolated foot, which is associated with a crocodilian tooth. The fossil belongs to a species about half the size of the smallest extant loon, and is morphologically most similar to the Paleogene taxon Colymboides. In all probability it constitutes the prey remains of a crocodilian, which is of particular significance because the distribution ranges of loons and crocodilians hardly overlap today. The Enspel palaeoclimate was warm-temperate and subtropical, and the Enspel specimen and other Paleogene fossils of gaviiform birds raise the, as yet, unanswered question of why loons largely disappeared from inland habitats of the warmer regions.
Alec R. Lindsay - One of the best experts on this subject based on the ideXlab platform.
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Genomic insights into natural selection in the common loon (Gavia immer): evidence for aquatic adaptation
BMC Evolutionary Biology, 2018Co-Authors: Zach G. Gayk, Diana Le Duc, Jeffrey Horn, Alec R. LindsayAbstract:Background The common loon ( Gavia immer ) is one of five species that comprise the avian order Gaviiformes. Loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. In this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. We used Illumina short read DNA sequence data from a female bird to produce a draft assembly of the common loon ( Gavia immer ) genome. Results We identified 14,169 common loon genes, which based on well-resolved avian genomes, represent approximately 80.7% of common loon genes. Evolutionary analyses between common loon and Adelie penguin ( Pygoscelis adeliae ), red-throated loon ( Gavia stellata ), chicken ( Gallus gallus ), northern fulmar ( Fulmarus glacialis ), and rock pigeon ( Columba livia ) show 164 positively selected genes in common and red-throated loons. These genes were enriched for a number of protein classes, including those involved in muscle tissue development, immunoglobulin function, hemoglobin iron binding, G-protein coupled receptors, and ATP metabolism. Conclusions Signatures of positive selection in these areas suggest the genus Gavia may have adapted for underwater diving by modulating their oxidative and metabolic pathways. While more research is required, these adaptations likely result in (1) compensations in oxygen respiration and energetic metabolism, (2) low-light visual acuity, and (3) elevated solute exchange. This work represents the first effort to understand the genomic adaptations of the common loon as well as other Gavia and may have implications for subsequent studies that target particular genes for loon population genetic, ecological or conservation studies.
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Genomic insights into natural selection in the common loon (Gavia immer): evidence for aquatic adaptation
BMC evolutionary biology, 2018Co-Authors: Zach G. Gayk, Diana Le Duc, Jeffrey Horn, Alec R. LindsayAbstract:The common loon (Gavia immer) is one of five species that comprise the avian order Gaviiformes. Loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. In this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. We used Illumina short read DNA sequence data from a female bird to produce a draft assembly of the common loon (Gavia immer) genome. We identified 14,169 common loon genes, which based on well-resolved avian genomes, represent approximately 80.7% of common loon genes. Evolutionary analyses between common loon and Adelie penguin (Pygoscelis adeliae), red-throated loon (Gavia stellata), chicken (Gallus gallus), northern fulmar (Fulmarus glacialis), and rock pigeon (Columba livia) show 164 positively selected genes in common and red-throated loons. These genes were enriched for a number of protein classes, including those involved in muscle tissue development, immunoglobulin function, hemoglobin iron binding, G-protein coupled receptors, and ATP metabolism. Signatures of positive selection in these areas suggest the genus Gavia may have adapted for underwater diving by modulating their oxidative and metabolic pathways. While more research is required, these adaptations likely result in (1) compensations in oxygen respiration and energetic metabolism, (2) low-light visual acuity, and (3) elevated solute exchange. This work represents the first effort to understand the genomic adaptations of the common loon as well as other Gavia and may have implications for subsequent studies that target particular genes for loon population genetic, ecological or conservation studies.
Evgenij Zvonok - One of the best experts on this subject based on the ideXlab platform.
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the tarsometatarsus of the middle eocene loon colymbiculus udovichenkoi
2013Co-Authors: Ursula B Gohlich, Andreas Kroh, Leonid Gorobets, Evgenij ZvonokAbstract:We describe the previously unknown tarsometatarsus of the earliest unambiguously identified loon, Colymbiculus udovichenkoi, from the Middle Eocene of the Ukraine. Except for being more elongate and apart from details of the hypotarsus morphology, the bone resembles the tarsometatarsus of the Early Miocene Colym- boides minutus. We consider the hypotarsus morphology of Colymbiculus to be plesiomorphic for Gaviiformes. Colymboides and crown group Gaviiformes are each characterized by an autapomorphic hypotarsus morphology, which precludes the former from being directly ancestral to the latter. The similarities shared by C. udovichenkoi and C. minutus, including their small size, are likely to be plesiomorphic for Gaviiformes. Although the disap- pearance of small stem group Gaviiformes may be related to the retreat of loons to cold Northern latitudes, more data are needed to firmly establish this hypothesis. We finally note that early Paleogene stem group Gaviiformes markedly differ from putative Late Cretaceous loons, whose identification needs to be verified by further fossil specimens.
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middle eocene pelagornithidae and Gaviiformes aves from the ukrainian paratethys
Palaeontology, 2011Co-Authors: Gerald Mayr, Evgenij ZvonokAbstract:: We describe avian remains from Novopskov, a new middle Eocene marine locality in Ukraine. The fossils constitute the most substantial collection of Palaeogene bird bones from Eastern Europe and contribute to a better knowledge of the Paratethyan seabird fauna. Most of the specimens belong to Pelagornithidae (bony-toothed birds), and two species of very different size can be distinguished. The larger of these is tentatively referred to Dasornis sp., the smaller to Odontopteryx toliapica. The specimens include skeletal elements that were not described for Palaeogene bony-toothed birds and document previously unknown morphological differences between Palaeogene and Neogene Pelagornithidae. It is argued that the purported crane Eobalearica tugarinovi, from the middle Eocene of Kyrgyzstan, is probably also a bony-toothed bird. A new genus and species of small Gaviiformes, Colymbiculus udovinchenkoi, is described, which is the earliest fossil record of a loon from Europe, preceding the next oldest specimens by more than 10 myr. The Ukrainian fossils document profound differences between middle Eocene and extant marine avifaunas of Europe, and whereas the middle Eocene Paratethyan avifauna appears to have been similar to that of the North Sea with regard to pelagornithid diversity, the absence of prophaethontids and relative abundance of Gaviiformes may indicate faunistic differences concerning the remaining seabirds.
Zach G. Gayk - One of the best experts on this subject based on the ideXlab platform.
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Genomic insights into natural selection in the common loon (Gavia immer): evidence for aquatic adaptation
BMC Evolutionary Biology, 2018Co-Authors: Zach G. Gayk, Diana Le Duc, Jeffrey Horn, Alec R. LindsayAbstract:Background The common loon ( Gavia immer ) is one of five species that comprise the avian order Gaviiformes. Loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. In this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. We used Illumina short read DNA sequence data from a female bird to produce a draft assembly of the common loon ( Gavia immer ) genome. Results We identified 14,169 common loon genes, which based on well-resolved avian genomes, represent approximately 80.7% of common loon genes. Evolutionary analyses between common loon and Adelie penguin ( Pygoscelis adeliae ), red-throated loon ( Gavia stellata ), chicken ( Gallus gallus ), northern fulmar ( Fulmarus glacialis ), and rock pigeon ( Columba livia ) show 164 positively selected genes in common and red-throated loons. These genes were enriched for a number of protein classes, including those involved in muscle tissue development, immunoglobulin function, hemoglobin iron binding, G-protein coupled receptors, and ATP metabolism. Conclusions Signatures of positive selection in these areas suggest the genus Gavia may have adapted for underwater diving by modulating their oxidative and metabolic pathways. While more research is required, these adaptations likely result in (1) compensations in oxygen respiration and energetic metabolism, (2) low-light visual acuity, and (3) elevated solute exchange. This work represents the first effort to understand the genomic adaptations of the common loon as well as other Gavia and may have implications for subsequent studies that target particular genes for loon population genetic, ecological or conservation studies.
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Genomic insights into natural selection in the common loon (Gavia immer): evidence for aquatic adaptation
BMC evolutionary biology, 2018Co-Authors: Zach G. Gayk, Diana Le Duc, Jeffrey Horn, Alec R. LindsayAbstract:The common loon (Gavia immer) is one of five species that comprise the avian order Gaviiformes. Loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. In this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. We used Illumina short read DNA sequence data from a female bird to produce a draft assembly of the common loon (Gavia immer) genome. We identified 14,169 common loon genes, which based on well-resolved avian genomes, represent approximately 80.7% of common loon genes. Evolutionary analyses between common loon and Adelie penguin (Pygoscelis adeliae), red-throated loon (Gavia stellata), chicken (Gallus gallus), northern fulmar (Fulmarus glacialis), and rock pigeon (Columba livia) show 164 positively selected genes in common and red-throated loons. These genes were enriched for a number of protein classes, including those involved in muscle tissue development, immunoglobulin function, hemoglobin iron binding, G-protein coupled receptors, and ATP metabolism. Signatures of positive selection in these areas suggest the genus Gavia may have adapted for underwater diving by modulating their oxidative and metabolic pathways. While more research is required, these adaptations likely result in (1) compensations in oxygen respiration and energetic metabolism, (2) low-light visual acuity, and (3) elevated solute exchange. This work represents the first effort to understand the genomic adaptations of the common loon as well as other Gavia and may have implications for subsequent studies that target particular genes for loon population genetic, ecological or conservation studies.
Jeffrey Horn - One of the best experts on this subject based on the ideXlab platform.
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Genomic insights into natural selection in the common loon (Gavia immer): evidence for aquatic adaptation
BMC Evolutionary Biology, 2018Co-Authors: Zach G. Gayk, Diana Le Duc, Jeffrey Horn, Alec R. LindsayAbstract:Background The common loon ( Gavia immer ) is one of five species that comprise the avian order Gaviiformes. Loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. In this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. We used Illumina short read DNA sequence data from a female bird to produce a draft assembly of the common loon ( Gavia immer ) genome. Results We identified 14,169 common loon genes, which based on well-resolved avian genomes, represent approximately 80.7% of common loon genes. Evolutionary analyses between common loon and Adelie penguin ( Pygoscelis adeliae ), red-throated loon ( Gavia stellata ), chicken ( Gallus gallus ), northern fulmar ( Fulmarus glacialis ), and rock pigeon ( Columba livia ) show 164 positively selected genes in common and red-throated loons. These genes were enriched for a number of protein classes, including those involved in muscle tissue development, immunoglobulin function, hemoglobin iron binding, G-protein coupled receptors, and ATP metabolism. Conclusions Signatures of positive selection in these areas suggest the genus Gavia may have adapted for underwater diving by modulating their oxidative and metabolic pathways. While more research is required, these adaptations likely result in (1) compensations in oxygen respiration and energetic metabolism, (2) low-light visual acuity, and (3) elevated solute exchange. This work represents the first effort to understand the genomic adaptations of the common loon as well as other Gavia and may have implications for subsequent studies that target particular genes for loon population genetic, ecological or conservation studies.
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Genomic insights into natural selection in the common loon (Gavia immer): evidence for aquatic adaptation
BMC evolutionary biology, 2018Co-Authors: Zach G. Gayk, Diana Le Duc, Jeffrey Horn, Alec R. LindsayAbstract:The common loon (Gavia immer) is one of five species that comprise the avian order Gaviiformes. Loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. In this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. We used Illumina short read DNA sequence data from a female bird to produce a draft assembly of the common loon (Gavia immer) genome. We identified 14,169 common loon genes, which based on well-resolved avian genomes, represent approximately 80.7% of common loon genes. Evolutionary analyses between common loon and Adelie penguin (Pygoscelis adeliae), red-throated loon (Gavia stellata), chicken (Gallus gallus), northern fulmar (Fulmarus glacialis), and rock pigeon (Columba livia) show 164 positively selected genes in common and red-throated loons. These genes were enriched for a number of protein classes, including those involved in muscle tissue development, immunoglobulin function, hemoglobin iron binding, G-protein coupled receptors, and ATP metabolism. Signatures of positive selection in these areas suggest the genus Gavia may have adapted for underwater diving by modulating their oxidative and metabolic pathways. While more research is required, these adaptations likely result in (1) compensations in oxygen respiration and energetic metabolism, (2) low-light visual acuity, and (3) elevated solute exchange. This work represents the first effort to understand the genomic adaptations of the common loon as well as other Gavia and may have implications for subsequent studies that target particular genes for loon population genetic, ecological or conservation studies.
