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David P. Mindell - One of the best experts on this subject based on the ideXlab platform.
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Rapid diversification of falcons (Aves: Falconidae) due to expansion of open habitats in the Late Miocene
Molecular Phylogenetics and Evolution, 2015Co-Authors: Jérôme Fuchs, Jeff A. Johnson, David P. MindellAbstract:Abstract Understanding how and why lineages diversify is central to understanding the origins of biological diversity. The avian family Falconidae (caracaras, forest-falcons, falcons) has an uneven distribution of species among multiple well-supported clades, and provides a useful system for testing hypotheses about diversification rate and correlation with environmental changes. We analyzed eight independent loci for 1–7 individuals from each of the 64 currently recognized Falconidae species, together with two fossil falconid temporal calibrations, to assess phylogeny, absolute divergence times and potential shifts in diversification rate. Our analyses supported similar diversification ages in the Early to Middle Miocene for the three traditional subfamilies, Herpetotherinae, Polyborinae and Falconinae. We estimated that divergences within the subfamily Falconinae began about 16 mya and divergences within the most species-rich genus, Falco , including about 60% of all Falconidae species, began about 7.5 mya. We found evidence for a significant increase in diversification rate at the basal phylogenetic node for the genus Falco , and the timing for this rate shift correlates generally with expansion of C4 grasslands beginning around the Miocene/Pliocene transition. Concomitantly, Falco lineages that are distributed primarily in grassland or savannah habitats, as opposed to woodlands, and exhibit migratory, as opposed to sedentary, behavior experienced a higher diversification rate.
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Molecular systematics of the caracaras and allies (Falconidae: Polyborinae) inferred from mitochondrial and nuclear sequence data
Ibis, 2012Co-Authors: Jérôme Fuchs, Jeff A. Johnson, David P. MindellAbstract:The Polyborinae is the most diverse subfamily of the Falconidae in terms of both morphology and behaviour, and includes falconet-shaped birds (Spiziapteryx), arboreal omnivores (Daptrius, Ibycter), as well as terrestrial generalists and scavengers (Caracara, Milvago and Phalcoboenus). The Polyborinae are endemic to the New World, with all but one species (Caracara cheriway) being restricted to Central and South America. Using over 7300 bp of mitochondrial and nuclear sequence data, we aim to clarify the taxonomy and biogeography of the Polyborinae. The genus Milvago was unexpectedly found to be polyphyletic, with Chimango Caracara Milvago chimango being related to the genus Phalcoboenus and Yellow-headed Caracara Milvago chimachima being sister to Daptrius. Furthermore, very low genetic divergence was found among the four species of the genus Phalcoboenus, with the lowest divergence being between White-throated Caracara Phalcoboenus albogularis and Mountain Caracara Phalcoboenus megalopterus. Our divergence time analyses revealed that the Polyborinae started to diversify in the Miocene, at about 14 Ma, and that the generalist ⁄scavenger behaviour in the Falconidae appeared between 14 and 6.6 Ma. All speciation events within the caracaras occurred during the Pleistocene. This situation differs from the general pattern described for forest birds, in which most diversification events are older, occurring primarily in the Pliocene and Miocene.
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Pliocene diversification within the South American Forest falcons (Falconidae: Micrastur).
Molecular phylogenetics and evolution, 2011Co-Authors: Jérôme Fuchs, Jeff A. Johnson, Steven Chen, David P. MindellAbstract:The Neotropics are one of the most species rich regions on Earth, with over 3150 species of birds. This unrivaled biodiversity has been attributed to higher proportions of mountain ranges, tropical rain forest or rain fall in the forest than in any other major biogeographic regions. Five primary hypotheses aim to explain processes of diversification within the Neotropics; (1) the Pleistocene refuge hypothesis, (2) the riverine barrier hypothesis, (3) the Miocene marine incursions hypothesis, (4) the ecological gradient hypothesis, and (5) the impact of the last Andean uplift serving as a barrier between eastern and western population Andean populations. We assessed these hypotheses to see which best explained the species richness of the forest-falcons (Micrastur), a poorly known lineage of birds that inhabit lowland and mid-elevation humid forest. Our analyses suggest all speciation events within the genus Micrastur probably occurred in the last 2.5–3.6 myrs, at or before the Pliocene/Pleistocene boundary, with the basal split within the genus being 7 myrs old. Hence our data allow us to formerly reject the classical Pleistocene refuge for Micrastur, Our divergence time estimates are younger that dates for the Miocene marine incursions, the riverine barrier and the Andean uplift hypotheses.
Jérôme Fuchs - One of the best experts on this subject based on the ideXlab platform.
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Rapid diversification of falcons (Aves: Falconidae) due to expansion of open habitats in the Late Miocene
Molecular Phylogenetics and Evolution, 2015Co-Authors: Jérôme Fuchs, Jeff A. Johnson, David P. MindellAbstract:Abstract Understanding how and why lineages diversify is central to understanding the origins of biological diversity. The avian family Falconidae (caracaras, forest-falcons, falcons) has an uneven distribution of species among multiple well-supported clades, and provides a useful system for testing hypotheses about diversification rate and correlation with environmental changes. We analyzed eight independent loci for 1–7 individuals from each of the 64 currently recognized Falconidae species, together with two fossil falconid temporal calibrations, to assess phylogeny, absolute divergence times and potential shifts in diversification rate. Our analyses supported similar diversification ages in the Early to Middle Miocene for the three traditional subfamilies, Herpetotherinae, Polyborinae and Falconinae. We estimated that divergences within the subfamily Falconinae began about 16 mya and divergences within the most species-rich genus, Falco , including about 60% of all Falconidae species, began about 7.5 mya. We found evidence for a significant increase in diversification rate at the basal phylogenetic node for the genus Falco , and the timing for this rate shift correlates generally with expansion of C4 grasslands beginning around the Miocene/Pliocene transition. Concomitantly, Falco lineages that are distributed primarily in grassland or savannah habitats, as opposed to woodlands, and exhibit migratory, as opposed to sedentary, behavior experienced a higher diversification rate.
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Molecular systematics of the caracaras and allies (Falconidae: Polyborinae) inferred from mitochondrial and nuclear sequence data
Ibis, 2012Co-Authors: Jérôme Fuchs, Jeff A. Johnson, David P. MindellAbstract:The Polyborinae is the most diverse subfamily of the Falconidae in terms of both morphology and behaviour, and includes falconet-shaped birds (Spiziapteryx), arboreal omnivores (Daptrius, Ibycter), as well as terrestrial generalists and scavengers (Caracara, Milvago and Phalcoboenus). The Polyborinae are endemic to the New World, with all but one species (Caracara cheriway) being restricted to Central and South America. Using over 7300 bp of mitochondrial and nuclear sequence data, we aim to clarify the taxonomy and biogeography of the Polyborinae. The genus Milvago was unexpectedly found to be polyphyletic, with Chimango Caracara Milvago chimango being related to the genus Phalcoboenus and Yellow-headed Caracara Milvago chimachima being sister to Daptrius. Furthermore, very low genetic divergence was found among the four species of the genus Phalcoboenus, with the lowest divergence being between White-throated Caracara Phalcoboenus albogularis and Mountain Caracara Phalcoboenus megalopterus. Our divergence time analyses revealed that the Polyborinae started to diversify in the Miocene, at about 14 Ma, and that the generalist ⁄scavenger behaviour in the Falconidae appeared between 14 and 6.6 Ma. All speciation events within the caracaras occurred during the Pleistocene. This situation differs from the general pattern described for forest birds, in which most diversification events are older, occurring primarily in the Pliocene and Miocene.
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Pliocene diversification within the South American Forest falcons (Falconidae: Micrastur).
Molecular phylogenetics and evolution, 2011Co-Authors: Jérôme Fuchs, Jeff A. Johnson, Steven Chen, David P. MindellAbstract:The Neotropics are one of the most species rich regions on Earth, with over 3150 species of birds. This unrivaled biodiversity has been attributed to higher proportions of mountain ranges, tropical rain forest or rain fall in the forest than in any other major biogeographic regions. Five primary hypotheses aim to explain processes of diversification within the Neotropics; (1) the Pleistocene refuge hypothesis, (2) the riverine barrier hypothesis, (3) the Miocene marine incursions hypothesis, (4) the ecological gradient hypothesis, and (5) the impact of the last Andean uplift serving as a barrier between eastern and western population Andean populations. We assessed these hypotheses to see which best explained the species richness of the forest-falcons (Micrastur), a poorly known lineage of birds that inhabit lowland and mid-elevation humid forest. Our analyses suggest all speciation events within the genus Micrastur probably occurred in the last 2.5–3.6 myrs, at or before the Pliocene/Pleistocene boundary, with the basal split within the genus being 7 myrs old. Hence our data allow us to formerly reject the classical Pleistocene refuge for Micrastur, Our divergence time estimates are younger that dates for the Miocene marine incursions, the riverine barrier and the Andean uplift hypotheses.
Olivier Duriez - One of the best experts on this subject based on the ideXlab platform.
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Visual configuration of two species of Falconidae with different foraging ecologies
Ibis, 2017Co-Authors: Simon Potier, Francesco Bonadonna, Graham R. Martin, Pierre François Isard, Thomas Dulaurent, Marielle Mentek, Olivier DuriezAbstract:Significant interspecific differences in avian vision occur, even in congeneric species, and these have been correlated with differences in the perceptual challenges associated with foraging. Although diurnal raptors are assumed to be mainly visually guided in their foraging, they differ markedly in their foraging tactics and this may result in different visual demands. Among the Falconidae (Falconiformes), most falcons forage mainly on the wing for highly mobile prey, whereas caracaras forage on the ground for carrion and insects. We assessed whether Saker Falcon Falco cherrug and Southern Caracara Caracara plancus differ in their visual abilities by determining the visual fields and foveal characteristics of both species. Using an ophthalmoscopic reflex technique, we found a higher degree of binocular overlap in the caracaras than in the falcons. The high binocular overlap (47 degrees) of the Southern Caracara may facilitate object manipulation (e.g. moving rocks) when foraging. We used an ultra-high resolution spectral-domain optical coherence tomography to determine foveal characteristics. We found two foveas (depressions in the retina where high visual resolution is expected) in the falcons (one central and one temporal) but only a central fovea in the caracaras. The presence of a shallower temporal fovea in Saker Falcons may help to fixate visually upon a highly mobile prey item during pursuit. We conclude that these differences in visual field configurations and foveal characteristics reflect different foraging demands, suggesting that the extraction of visual information is finely tuned to the demands of their foraging tactics. (Less)
Anderson Guzzi - One of the best experts on this subject based on the ideXlab platform.
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Osteologia craniana de Micrastur semitorquatus Vieillot, 1817 (Falconiformes: Falconidae)
2012Co-Authors: Andreza Gomes Da Silva, José Bolzani De Ferreira, Reginaldo José Donatelli, Anderson GuzziAbstract:Micrastur semitorquatus e popularmente conhecido como falcao-relogio, habitante das florestas da regiao Neotropical. Estudos sobre sua osteologia craniana sao escassos na literatura. Procurou-se, neste trabalho, descrever sua osteologia craniana e, com base nesta descricao, comparar com outras especies de aves de rapina, buscando ampliar o conhecimento sobre a anatomia dessa especie. Foram utilizados tres especimes de M. semitorquatus, que fazem parte da colecao osteologica da Bird Division at the Smithsonian National Museum of Natural History (USNM), Washington, DC, EUA (USNM: 245788, USNM 013493 e USNM 289773). Apesar da relacao entre a forma de uma estrutura e sua funcao nao seja completamente estabelecida, muitas das adaptacoes do crânio de M. semitorquatus podem estar relacionadas aos seus habitos de vida e comportamento, como o estreitamento da largura interorbital,; a robustez da pila supranasal aliado ao procinetismo do cranio; um desenvolvido processo pos-orbital, e a expansao do palatino. Alem disso, a osteologia craniana de M. semitorquatus pode fornecer caracteres uteis a analise cladistica, podendo sustentar hipoteses de relacionamento filogenetico dessa especie com outras do mesmo genero ou da mesma familia.
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cranial osteology of micrastur semitorquatus vieillot 1817 falconiformes Falconidae
Comunicata Scientiae, 2012Co-Authors: Andreza Gomes Da Silva, Reginaldo José Donatelli, Guilherme Jose Bonzan De Campos Ferreira, Anderson GuzziAbstract:Micrastur semitorquatus , popularly known as Collared Forest-Falcon is an inhabitant of the rainforests of the Neotropical Region. Studies on the cranial osteology are scarce in the literature. To increase the knowledge about the anatomy of this species its cranial osteology was described and compared with other species of birds of prey. Three specimens of M. semitorquatus were examined at the Bird Division of the osteological collection at the Smithsonian National Museum of Natural History (USNM), Washington, DC (USNM: 245788, USNM 013493 and USNM 289773). Although the relationship between the form of a structure and its function is not fully established, many of the adaptations of the skull of M. semitorquatus may be related to this lifestyle and behavior, such as narrowing of the interorbital width, the robustness of pila supranasalis coupled with the prokinesis of the skull, a process developed post-orbital, and palatine expansion. In addition, the cranial osteology of M. semitorquatus can provide useful characters for cladistic analysis, sustaining the hypothesis of phylogenetic relationships with other species of the same genus or the same family.
Mosto, María Clelia - One of the best experts on this subject based on the ideXlab platform.
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Tail myology and flight behaviour: Differences between caracaras, falcons and forest falcons (Aves, Falconiformes)
'Wiley', 2019Co-Authors: Mosto, María Clelia, Picasso, Mariana Beatriz Julieta, Montes, Martin Miguel, Krone OliverAbstract:Caracaras, falcons and forest falcons, which are representative of the three subfamilies of the family Falconidae, have different flight behaviour. Since, during flight, the tail works in coordination with the wings, the tail muscles could be indicative of the type of flight behaviour. The aim of this work was to describe in detail the little-known tail muscles of the Falconidae and to explore their possible association with this different behaviour, by using the muscle mass as an indicator. To this end, the tail muscles of 18 specimens representing the three subfamilies of Falconidae were dissected, weighed and their percentage to the body mass calculated. The possible differences in tail muscle mass between Falconinae and Polyborinae were explored with a Bayesian statistical approach. In all species, the muscles depressor caudae and levator caudae had the highest mass values (0.028%–0.329% and 0.120%–0.274%, respectively), in accordance with the key movements performed during flight, that is, the tail depression and elevation. The total muscle masses of Falconinae and those of Polyborinae were significantly different (p
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Wing myology of Caracaras (Aves, Falconiformes): muscular features associated with flight behavior
Senckenberg Gesellschaft für Naturforschung, 2018Co-Authors: Picasso, Mariana Beatriz Julieta, Mosto, María CleliaAbstract:Caracaras (Aves, Falconiformes, Falconidae) are Neotropical diurnal raptors that belong to the subfamily Polyborinae. The forelimb myology of this group has not been comprehensively studied or compared with that of other Falconidae. Thus, the aims of this study were i) to describe the forelimb muscles of two species of Polyborinae (Caracara plancus and Milvago chimango), ii) to explore the possible relationship between muscular features and their function in flight behavior and iii) to compare the muscular features of these species with those of species of the subfamily Falconinae. To this end, the forelimb muscles of C. plancus (n=4) and M. chimango (n=4) were dissected. Additonally, to complement this data set, two specimens of M. chimachima were dissected. The mass of each muscle of one wing and its percentage with respect to the body mass were obtained. A total of 45 muscles were identified, and differences with respect to Falconinae were related to the presence of single or additional bellies. The total forelimb muscle mass represented between 7.68 and 10.26 % of the body mass. The muscle pectoralis represented ̴ 5% of the body mass, followed by the muscles scapulohumeralis caudalis (0.64–0.79%), deltoideus major (0.43 –0.53%), supracoracoideus (0.34– 0.38%) and biceps brachii (0.26 –0.39%). The high values of these muscles are in agreement with their important function: they are involved in the downstroke and upstroke phases of the flapping flight. On the other hand, the muscles that seemed to contribute little to the mechanical power for flight presented low values that ranged between 0.01 and 0.25%. Comparison of the forelimb muscles of caracaras with published data on Falconinae species suggests that their muscular features might be associated with their type of flight, which is more erratic and less powerful than that of Falconinae
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Wing myology of Caracaras (Aves, Falconiformes): muscular features associated with flight behavior
Senckenberg Gesellschaft für Naturforschung, 2018Co-Authors: Picasso, Mariana Beatriz Julieta, Mosto, María CleliaAbstract:Caracaras (Aves, Falconiformes, Falconidae) are Neotropical diurnal raptors that belong to the subfamily Polyborinae. The forelimb myology of this group has not been comprehensively studied or compared with that of other Falconidae. Thus, the aims of this study were i) to describe the forelimb muscles of two species of Polyborinae (Caracara plancus and Milvago chimango), ii) to explore the possible relationship between muscular features and their function in flight behavior and iii) to compare the muscular features of these species with those of species of the subfamily Falconinae. To this end, the forelimb muscles of C. plancus (n=4) and M. chimango (n=4) were dissected. Additonally, to complement this data set, two specimens of M. chimachima were dissected. The mass of each muscle of one wing and its percentage with respect to the body mass were obtained. A total of 45 muscles were identified, and differences with respect to Falconinae were related to the presence of single or additional bellies. The total forelimb muscle mass represented between 7.68 and 10.26 % of the body mass. The muscle pectoralis represented ̴ 5% of the body mass, followed by the muscles scapulohumeralis caudalis (0.64–0.79%), deltoideus major (0.43 –0.53%), supracoracoideus (0.34– 0.38%) and biceps brachii (0.26 –0.39%). The high values of these muscles are in agreement with their important function: they are involved in the downstroke and upstroke phases of the flapping flight. On the other hand, the muscles that seemed to contribute little to the mechanical power for flight presented low values that ranged between 0.01 and 0.25%. Comparison of the forelimb muscles of caracaras with published data on Falconinae species suggests that their muscular features might be associated with their type of flight, which is more erratic and less powerful than that of Falconinae.Fil: Picasso, Mariana Beatriz Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Mosto, María Clelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentin
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Comparative hindlimb myology within the family Falconidae
Springer, 2017Co-Authors: Mosto, María CleliaAbstract:A characteristical feature of a raptors’ hindlimb is their strengthen musculature that aids gripping prey with their sharp talons. To trace specific anatomical modifications it is necessary to study closely related species, with this aim, the myology of the hindlimb of the three subfamilies of Falconidae is explored. For this, a description of a Herpetotherinae member (Micrastur ruficollis) was made for the first time. The hindlimb muscle mass of Polyborinae, Falconinae and Herpetotherinae was compared according to their main function (flexion and extension) on their joints (femur, tibiotarsus, tarsometatarsus and digits). The pattern of Micrastur ruficollis resembles that of the Falconidae except for a few differences towards the development of certain muscles. As it is noteworthy the presence of the second belly of the musculus flexor cruris medialis (unique among birds), its identity will be discussed. Also, Micrastur ruficollis had the highest values of the hindlimb mass. Polyborinae and Falconinae had several differences between each other. The muscles mass of the hip and knee, both flexion and extension, were higher in the Polyborinae, this is in accordance to their more terrestrial habit. Instead, Falconinae had a higher mass in the m. flexor digitorum longus, m. flexor hallucis longus and m. tibialis cranialis, the most important muscles for gripping prey.Fil: Mosto, María Clelia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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Long-legged caracaras: Terrestrial habitat and hindlimb morphology
'Wiley', 2016Co-Authors: Mosto, María Clelia, Picasso, Mariana Beatriz Julieta, Biondi, Laura MarinaAbstract:The hindlimb of the Polyborinae has always been characterized as long when it was compared with other diurnal raptors; however, no empirical work has been done to support such a traditional well-known fact. The objective of this work is to analyze the femur, tibiotarsus and tarsometatarsus of this group to corroborate whether this assumption has a significant statistical support. The proportions of these bones were analyzed with a one-way Kruskal-Wallis test and Dunn's test as post hoc comparisons. The allometric relationships between the long bones and body mass or the total length of the hindlimb were carried out with the reduced major axis method. In addition, the osteological study is complemented with a myological dissection of the hindlimb of Milvago chimachima and Caracara plancus. The three long bones of the limb of Polyborinae show significant differences with those from Falconinae. The presence of a long tarsometatarsus is a typical feature of terrestrial birds, it produces an increase in length stride allowing an effective locomotion on land. Among the myological differences, the most prominent are the presence of the musculus flexor cruris lateralis (absent in other Falconidae) and a well-developed musculus fibularis longus. These osseous and myological features are related to the terrestrial locomotion present in this subfamily.Fil: Mosto, María Clelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Picasso, Mariana Beatriz Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Biondi, Laura Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin