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Rodrigo A. Vásquez - One of the best experts on this subject based on the ideXlab platform.
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Breeding biology in a population of Rufous-Collared Sparrow (Zonotrichia capensis, Statius Müller, 1776) at different elevations in the Tropical Andes
Biota Neotropica, 2021Co-Authors: Leydy J. Cardona-salazar, Rodrigo A. Vásquez, Ana Busi, Daniela Gómez Castillo, Paula A. Ossa-lópez, Fredy A. Rivera-páez, Gabriel J. Castaño-villaAbstract:Abstract: Breeding biology in a population of Rufous-Collared Sparrow (Zonotrichia capensis, Statius Müller, 1776) at different elevations in the Tropical Andes. Elevation strongly influences the evolution of life history traits associated with bird physiology and reproduction. Since life history traits in birds are modulated by environmental factors that vary with elevation, we expected to find changes in breeding biology traits of Z. capensis at different elevations. In this study, we compared the breeding biology (clutch size, egg volume, and reproductive activity) of a non-migratory population of Z. capensis in two localities at different elevations (low and high elevations, 1 800 m a.s.l., and 3 800 m a.s.l., respectively) and same latitude in the Colombian Tropical Andes for a one-year period. We found no differences in clutch size between the localities; however, egg volume was higher at high elevation. Furthermore, the reproductive activity differed significantly between localities. We propose that clutch size is likely conserved throughout the altitudinal distribution of Z. capensis since the species evolved in Tropical lowlands. On the other hand, the larger egg volume at high elevation could obey local environmental factors that may favor the reproductive success of the population.
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Differences in circulating corticosterone levels associated with elevation of breeding sites in Rufous-Collared Sparrows Zonotrichia capensis
Journal of Ornithology, 2020Co-Authors: Yanina Poblete, John C Wingfield, Paulina L. González-gómez, Víctor L. Gutiérrez, Rodrigo A. VásquezAbstract:To facilitate breeding and any energetically costly activity, individuals of the same species can substantially vary their circulating corticosterone (CORT) levels to cope with local environmental conditions at different elevations. We compared baseline and the stress-induced plasma CORT levels during the parental care stage between free-living Rufous-Collared Sparrows (Zonotrichia capensis) that breed at high (~ 2500 m) and low (~ 500 m) elevations in central Chile. We found that baseline CORT levels at different elevations were similar and that stress-induced levels were significantly lower in birds breeding at high elevation; however, we detected no sexual dimorphism in CORT levels related to elevation. We found that larger individuals had higher stress-induced CORT levels at low elevation regardless of sex. Our results show that environmental conditions at high elevation seem to be not severe enough to promote more elevated baseline CORT levels. However, breeding Rufous-Collared Sparrow must still deal with both shorter breeding seasons and increased exposure to unpredictable events. Thus, a reduced stress response during the parental care stage would be more favorable for supporting breeding activities at high elevations. Future studies should focus on describing the life-history traits of these populations and the effects that other stressors, such as predation pressure and food availability, may have on the adrenocortical response in these environments to evaluate the consequences for survival and reproductive success. This information is important for enhancing our understanding of the ecological and evolutionary mechanisms that modulate variation in the adrenocortical response among populations of the same species.
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Morphological differences in a population of Rufous-Collared Sparrow (Zonotrichia capensis, Statius Müller, 1776) (Passerine, Emberizidae) at different elevations in the Tropical Andes
Biota Neotropica, 2020Co-Authors: Ana Busi, Rodrigo A. Vásquez, Leydy J. Cardona-salazar, Daniela Gómez Castillo, Paula A. Ossa-lópez, Fredy A. Rivera-páez, Gabriel J. Castaño-villaAbstract:Abstract Populations that breed along steep elevation gradients show diverse physiological and morphological changes in response to the different environmental conditions. The latter has been discussed by Bergmann’s and Allen’s ecogeographic rules about body and appendage sizes and environmental temperature. We compared morphometric measures (mass, bill width, tarsus, wing, and tail length) of a Zonotrichia capensis population in two localities at different elevations with similar latitudes and photoperiods on the western slope of the Colombian Central Andes. We compared a Low Elevation locality (LE) at 1800 m a.s.l. and a High Elevation locality (HE) at 3853 m a.s.l. that have approximate wind speeds of 1.3 m/s and 8.4 m/s, respectively. During 12 months of sampling, we captured 46 adults using mist-nets; 26 in the LE and 20 in the HE. Each individual was sexed using molecular techniques at the Laboratory of Genetics of the Department of Biological Sciences of Universidad de Caldas. Individuals (males + females) from the HE had longer wings and tails than those from the LE (F1,44 = 5.93; P = 0.019). Also, wings of males in the HE were longer than those of females in both localities and tails of males in the HE were longer than those of LE males. Our results did not agree with what was expected according to Allen’s and Bergmann’s ecogeographic rules. Longer wings and tails increase sustainment, maneuverability, and balance in low atmospheric pressures and strong air currents and these conditions are found at high elevation habitats. Most likely, the longer wings found for HE males allow greater movement during territorial behavior. Further, these differences in morphological traits along elevational gradients could result from micro-evolutionary changes between localities or phenotypic plasticity of individuals exposed to different environmental conditions.
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Seasonal modulation of the adrenocortical stress responses in Chilean populations of Zonotrichia capensis
Journal of Ornithology, 2018Co-Authors: Aaron D Clark, Elizabeth A. Addis, Rodrigo A. Vásquez, John C WingfieldAbstract:To persist in a landscape, organisms are often faced with evolutionary tradeoffs between individual survival and reproduction. In environments where breeding opportunities are brief, it has been hypothesized that individuals will decrease investments in self-preservation in favor of reproductive success. Many avian species in the Northern Hemisphere have been shown to diminish their physiological response to perturbations of the environment by decreasing the adrenocortical response to acute stress during the parental care phase of reproduction. We present results from three populations of Rufous-Collared Sparrow (Zonotrichia capensis) in the Southern Hemisphere in which we compared the dynamics of changes in plasma levels of corticosterone after capture, handling and restraint in pre-breeding and nesting phases. The results suggest that the degree of seasonal reduction of the adrenocortical stress response in parental birds is different from that of congeners in the Northern Hemisphere. Males of all three populations of Z. capensis in our study attenuated the adrenocortical stress response equally between the early breeding and parental sub-phases of nesting despite breeding at very different altitudes and latitudes. In contrast, females from all three populations showed no seasonal attenuation of the adrenocortical stress response over the seasons examined in this study. These findings suggest that further comparative investigations are needed to compare Northern Hemisphere-based endocrine patterns in different, global contexts.
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Intraspecific variation in exploratory behavior and elevational affinity in a widely distributed songbird
Oecologia, 2018Co-Authors: Yanina Poblete, Víctor Gutiérrez, Seth D. Newsome, Pablo Sabat, Rodrigo A. VásquezAbstract:Populations of the same species can vary substantially in their behavioral and morphometric traits when they are subject to different environmental pressures, which may lead to the development of different adaptive strategies. We quantified variation in exploratory behavior and morphometric traits among two Rufous-Collared Sparrow populations that occur at low and high elevations in central Chile. Moreover, we used census and δ^2H values of feather and blood to evaluate migration. We found that individual Sparrows inhabiting high elevations were larger and showed more intense exploratory behavior in comparison with those that were captured at lower elevation. Moreover, we observed a steady decline in Sparrow abundance during the winter and similar δ^2H values for blood collected in the winter and summer at this site, which were significantly lower than blood δ^2H values observed at low elevation. This pattern suggests that individuals do not move long distances during winter, and likely they remain at similar elevations in refuge habitats. As predicted, our results support the existent of different adaptive strategies among populations of the same species, and suggest that the combination of behavioral, morphometric, and stable isotope data is a novel and robust integrative approach to assess differences in adaptation across environmental gradients.
Stephen C. Lougheed - One of the best experts on this subject based on the ideXlab platform.
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Spatial distribution, prevalence and diversity of haemosporidians in the Rufous-Collared Sparrow, Zonotrichia capensis
Parasites & Vectors, 2019Co-Authors: Daniela Doussang, Luis Gonzalo Torres-fuentes, Rute Beatriz Clemente-carvalho, Kian Connelly Greene, Daniel González-acuña, Stephen C. Lougheed, Juliana A ViannaAbstract:Background Parasite prevalence and diversity are determined by the distribution of hosts and vectors and by the interplay among a suite of environmental factors. Distributions of parasite lineages vary based on host susceptibility and geographical barriers. Hemoparasites of the genera Haemoproteus and Plasmodium have wide distributions, and high prevalence and genetic diversity within perching birds (Order Passeriformes). The Rufous-Collared Sparrow ( Zonotrichia capensis ) is widely distributed in Central and South America across an immense diversity of environments from sea level to more than 4000 meters above sea level. It therefore provides an excellent model to investigate whether altitudinal and latitudinal gradients influence the distribution, prevalence and diversity of haemosporidian parasites, their population structure and the biogeographical boundaries of distinct parasite lineages. Results We assembled samples from 1317 Rufous-Collared Sparrows spanning 75 locales from across Central and South America (between 9.5°N and 54°S; 10–4655 meters above sea level). We used DNA sequence data from a fragment of the mitochondrial cytochrome b gene ( cytb ) of Haemoproteus and Plasmodium from 325 positive samples and found prevalences of 22 and 3%, respectively. Haemoproteus exhibited a higher prevalence than Plasmodium but with comparatively lower genetic diversity. We detected a relationship of Plasmodium and Haemoproteus prevalence with altitude and latitude; however, altitude and latitude did not influence parasite diversity. Conclusions Parasite lineages showed a phylogeographical boundary coincident with the Andes Mountains, although we also observed a north-south disjunction in Peru for Haemoproteus . Haemosporidian distribution was not homogeneous but differed based on latitude and altitude. This is most probably due to environmental factors that have influenced both vector distribution and abundance, as well as parasite development. Our study provides key insights on the distribution of haemoparasite lineages and parasite dynamics within hosts.
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Spatial distribution, prevalence and diversity of haemosporidians in the Rufous-Collared Sparrow, Zonotrichia capensis
Parasites & vectors, 2019Co-Authors: Daniela Doussang, Luis Gonzalo Torres-fuentes, Rute Beatriz Clemente-carvalho, Kian Connelly Greene, Daniel González-acuña, Stephen C. Lougheed, Juliana A ViannaAbstract:Parasite prevalence and diversity are determined by the distribution of hosts and vectors and by the interplay among a suite of environmental factors. Distributions of parasite lineages vary based on host susceptibility and geographical barriers. Hemoparasites of the genera Haemoproteus and Plasmodium have wide distributions, and high prevalence and genetic diversity within perching birds (Order Passeriformes). The Rufous-Collared Sparrow (Zonotrichia capensis) is widely distributed in Central and South America across an immense diversity of environments from sea level to more than 4000 meters above sea level. It therefore provides an excellent model to investigate whether altitudinal and latitudinal gradients influence the distribution, prevalence and diversity of haemosporidian parasites, their population structure and the biogeographical boundaries of distinct parasite lineages. We assembled samples from 1317 Rufous-Collared Sparrows spanning 75 locales from across Central and South America (between 9.5°N and 54°S; 10–4655 meters above sea level). We used DNA sequence data from a fragment of the mitochondrial cytochrome b gene (cytb) of Haemoproteus and Plasmodium from 325 positive samples and found prevalences of 22 and 3%, respectively. Haemoproteus exhibited a higher prevalence than Plasmodium but with comparatively lower genetic diversity. We detected a relationship of Plasmodium and Haemoproteus prevalence with altitude and latitude; however, altitude and latitude did not influence parasite diversity. Parasite lineages showed a phylogeographical boundary coincident with the Andes Mountains, although we also observed a north-south disjunction in Peru for Haemoproteus. Haemosporidian distribution was not homogeneous but differed based on latitude and altitude. This is most probably due to environmental factors that have influenced both vector distribution and abundance, as well as parasite development. Our study provides key insights on the distribution of haemoparasite lineages and parasite dynamics within hosts.
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Additional file 5: of Spatial distribution, prevalence and diversity of haemosporidians in the Rufous-Collared Sparrow, Zonotrichia capensis
2019Co-Authors: Daniela Doussang, Luis Gonzalo Torres-fuentes, Rute Beatriz Clemente-carvalho, Daniel González-acuña, Stephen C. Lougheed, Kian Greene, Juliana ViannaAbstract:Table S4. Pairwise Fst values calculated from mtDNA Haemoproteus sequences between countries and geographical areas of Chile. (DOCX 45 kb
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Secondary contact followed by gene flow between divergent mitochondrial lineages of a widespread Neotropical songbird (Zonotrichia capensis)
Biological Journal of the Linnean Society, 2014Co-Authors: Leonardo Campagna, Pablo L. Tubaro, Cecilia Kopuchian, Stephen C. LougheedAbstract:1 * Understanding how genetic and phenotypic differences that arise in geographically isolated populations influence the outcome of secondary contact advances our knowledge of speciation. In the present study, we investigate the secondary contact between divergent lineages of a widespread Neotropical songbird, the Rufous-Collared Sparrow (Zonotrichia capensis). Zonotrichia capensis is morphologically and behaviourally diverse, and shows a pattern of lineage diversification produced by a Pleistocene expansion and colonization of South America from a probable Central American origin. Consistent with previous results, we find three lineages throughout the species range, showing between 1.5% and 2.5% divergence in mitochondrial control region sequences. These lineages come into secondary contact in the Dominican Republic, La Paz (Bolivia), and North-eastern Argentina. We use DNA microsatellite data to study a broad secondary contact zone in North-eastern Argentina, finding that Bayesian clustering analyses do not assign individuals to their respective mitochondrial lineages. Overall, we did not observe nuclear genetic discontinuities in the study area. We conclude that, if genetic, morphological, and/or cultural differences accumulated among lineages during isolation, they were insufficient to prevent gene flow after secondary contact. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111, 863-868.
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Continental phylogeography of an ecologically and morphologically diverse Neotropical songbird, Zonotrichia capensis
BMC evolutionary biology, 2013Co-Authors: Stephen C. Lougheed, Pablo L. Tubaro, Dario A Lijtmaer, Leonardo Campagna, José A. Dávila, Paul HandfordAbstract:The Neotropics are exceptionally diverse, containing roughly one third of all extant bird species on Earth. This remarkable species richness is thought to be a consequence of processes associated with both Andean orogenesis throughout the Tertiary, and climatic fluctuations during the Quaternary. Phylogeographic studies allow insights into how such events might have influenced evolutionary trajectories of species and ultimately contribute to a better understanding of speciation. Studies on continentally distributed species are of particular interest because different populations of such taxa may show genetic signatures of events that impacted the continent-wide biota. Here we evaluate the genealogical history of one of the world’s most broadly-distributed and polytypic passerines, the Rufous-Collared Sparrow (Zonotrichia capensis). We obtained control region DNA sequences from 92 Zonotrichia capensis individuals sampled across the species’ range (Central and South America). Six additional molecular markers, both nuclear and mitochondrial, were sequenced for a subset of individuals with divergent control region haplotypes. Median-joining network analysis, and Bayesian and maximum parsimony phylogenetic analyses all recovered three lineages: one spanning Middle America, the Dominican Republic, and north-western South America; one encompassing the Dominican Republic, Roraima (Venezuela) and La Paz (Bolivia) south to Tierra del Fuego, Argentina; and a third, including eastern Argentina and Brazil. Phylogenetic analyses suggest that the Middle American/north-western South American clade is sister to the remaining two. Bayesian and maximum likelihood coalescent simulations used to study lineage demographic history, diversification times, migration rates and population expansion together suggested that diversification of the three lineages occurred rapidly during the Pleistocene, with negligible gene flow, leaving genetic signatures of population expansions. The Pleistocene history of the Rufous-Collared Sparrow involved extensive range expansion from a probable Central American origin. Its remarkable morphological and behavioral diversity probably represents recent responses to local conditions overlying deeper patterns of lineage diversity, which are themselves produced by isolation and the history of colonization of South America.
Paul Handford - One of the best experts on this subject based on the ideXlab platform.
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Continental phylogeography of an ecologically and morphologically diverse Neotropical songbird, Zonotrichia capensis
BMC evolutionary biology, 2013Co-Authors: Stephen C. Lougheed, Pablo L. Tubaro, Dario A Lijtmaer, Leonardo Campagna, José A. Dávila, Paul HandfordAbstract:The Neotropics are exceptionally diverse, containing roughly one third of all extant bird species on Earth. This remarkable species richness is thought to be a consequence of processes associated with both Andean orogenesis throughout the Tertiary, and climatic fluctuations during the Quaternary. Phylogeographic studies allow insights into how such events might have influenced evolutionary trajectories of species and ultimately contribute to a better understanding of speciation. Studies on continentally distributed species are of particular interest because different populations of such taxa may show genetic signatures of events that impacted the continent-wide biota. Here we evaluate the genealogical history of one of the world’s most broadly-distributed and polytypic passerines, the Rufous-Collared Sparrow (Zonotrichia capensis). We obtained control region DNA sequences from 92 Zonotrichia capensis individuals sampled across the species’ range (Central and South America). Six additional molecular markers, both nuclear and mitochondrial, were sequenced for a subset of individuals with divergent control region haplotypes. Median-joining network analysis, and Bayesian and maximum parsimony phylogenetic analyses all recovered three lineages: one spanning Middle America, the Dominican Republic, and north-western South America; one encompassing the Dominican Republic, Roraima (Venezuela) and La Paz (Bolivia) south to Tierra del Fuego, Argentina; and a third, including eastern Argentina and Brazil. Phylogenetic analyses suggest that the Middle American/north-western South American clade is sister to the remaining two. Bayesian and maximum likelihood coalescent simulations used to study lineage demographic history, diversification times, migration rates and population expansion together suggested that diversification of the three lineages occurred rapidly during the Pleistocene, with negligible gene flow, leaving genetic signatures of population expansions. The Pleistocene history of the Rufous-Collared Sparrow involved extensive range expansion from a probable Central American origin. Its remarkable morphological and behavioral diversity probably represents recent responses to local conditions overlying deeper patterns of lineage diversity, which are themselves produced by isolation and the history of colonization of South America.
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temporal stability and change in a microgeographical pattern of song variation in the rufous collared Sparrow
Animal Behaviour, 2004Co-Authors: Cecilia Kopuchian, Pablo L. Tubaro, Dario A Lijtmaer, Paul HandfordAbstract:We studied the pattern of song variation in the Rufous-Collared Sparrow, Zonotrichia capensis, in the 1987 and 2000 breeding seasons in a 7-km2 area covering open and closed habitats. We measured 14 quantitative song variables over a total of 390 individuals and found consistent differences between habitats in both years. In particular, songs of individuals from closed habitat sites had trills with longer trill intervals and lower frequencies than those of individuals from open habitats. This pattern of variation is interpreted as a song cline that correlates with the environmental gradient. Although this cline was stable in location and shape, it also showed several differences between years. The songs recorded during 2000 had trills with longer trill intervals and lower minimum frequencies than those recorded during 1987. Thus, this study is the first to directly document temporal changes in song variables in a Z. capensis population. This change would be expected if all the habitats studied were more closed in 2000 than in 1987, but we did not find obvious differences in habitat features between seasons. However, this modification of song structure is compatible with alternative explanations, such as subtle differences in habitat characteristics, changes in climatic variables, a delayed effect of a past modification of the environment and neutrality of the change.
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geographic variation in the song of the rufous collared Sparrow in eastern argentina
The Condor, 1993Co-Authors: Pablo L. Tubaro, Enrique T Segura, Paul HandfordAbstract:Variation in trill features of Rufous-Collared Sparrow (Zonotrichia capensis) song is described in three sites located on the northeast coast of Buenos Aires Province, Argentina. There is a distinctive "talar" dialect in sites supporting natural woodlands. This dialect is characterized by slower trills with lower minimum frequencies than the one present in the open grassy fields ("steppe" dialect). Talar dialect is absent in a site where natural woodlands have been replaced by grassy fields and open man-made parks, suggesting that the vocal tradition changed after habitat modification. Detailed analysis reveals that talar and steppe dialects intergrade in a song cline, following the vegetational ecotone. This song cline has been stable in location and features during the last decade, even though there were no geographic barriers impairing population or cultural exchange between habitats.
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Mitochondrial DNA Hyperdiversity and Vocal Dialects in a Subspecies Transition of the Rufous-Collared Sparrow
The Condor, 1993Co-Authors: Stephen C. Lougheed, Paul Handford, Allan J. BakerAbstract:The Rufous-Collared Sparrow, Zonotrichia capensis, is widely distributed in neotropical America and shows extensive variation in its learned song. In northwestern Argentina it exhibits song dialects which map closely onto the distribution of natural vegetation assemblages. To date, there is no evidence ofa correlation between genetic (allozyme) variation and dialects. However, recent genetic structuring produced through philopatry and assortative mating by dialect is difficult to demonstrate statistically with such proteinencoding nuclear genes. Therefore, we assayed variation in more rapidly evolving mitochondrial DNA along a 50 km transect, which spans three dialect boundaries between four adjacent habitat-types (from ~ 1,800 m to ~-3,000 m), using restriction fragment length polymorphism analysis. This revealed exceptional diversity (41 clones from 42 individuals), a level comparable with DNA-fingerprinting, and higher than reported in any passerine over such a small area to date. The degree of nucleotide divergence between the two main clusters of mtDNA haplotypes implies a separation time in excess of one million years. The mtDNA variability is not related to song dialects; rather it is interpreted as a reflection of secondary introgression between two well-differentiated subspecies whose ranges abut in this region.
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FREQUENCY CHARACTERS IN POPULATIONS OF THE Rufous-Collared Sparrow (ZONOTRICHIA CAPEN$I$)
1993Co-Authors: Stephen C. Lougheed, Paul HandfordAbstract:We collected 474 specimens of male Rufous-Collared Sparrows (Zonotrichia ca- pensis) from 24 sites in northwestern Argentina. Four samples were obtained from each of six habitats: lowland chaco thornscrub, transition forest, montane woodland, montane grass- land, Monte desert scrub, and puna high-altitude scrub. Puna birds (Z. c. pulacayensis) were differentiated both genetically and morphologically from all other birds in the sample (Z. c. hypoleuca). However, the steepness and location of the clines for these two character types were substantially different. An abrupt cline in PGM-1 allozyme frequencies was apparent in the extreme northwest of our study area, while clines in morphological features (primarily body size) were gradual and extended much further southward. Among nonpuna samples (20 sites; Z. c. hypoleuca), patterns of intersite differentiation in morphological and allozyme characters were unrelated. Partial Mantel's tests showed that, among these samples, both degree of difference in habitat structure and linear geographic distance are important cor- relates of among-site morphological differentiation. Similar tests demonstrated that neither of these two environmental factors is related statistically to genetic differentiation among popula- tions. Received 3 October 1991, accepted 21 November 1992. THE STUDY of geographic variation of various types of characters (e.g. morphological, physi- ological, genetic, behavioral) is central to an understanding of evolutionary processes. Her- itable variation is the raw material for natural
Pablo Sabat - One of the best experts on this subject based on the ideXlab platform.
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The interplay between ambient temperature and salt intake affects oxidative status and immune responses in a ubiquitous Neotropical passerine, the Rufous-Collared Sparrow.
Comparative biochemistry and physiology. Part A Molecular & integrative physiology, 2019Co-Authors: Pablo Sabat, Seth D. Newsome, Francisco Bozinovic, Carolina Contreras-ramos, Roberto F. Nespolo, Verónica Quirici, Karin Maldonado, Isaac Peña-villalobos, Natalia Ramirez-otarola, Juan C. Sanchez-hernandezAbstract:Physiological traits associated with maintenance, growth, and reproduction demand a large amount of energy and thus directly influence an animal's energy budget, which is also regulated by environmental conditions. In this study, we evaluated the interplay between ambient temperature and salinity of drinking water on energy budgets and physiological responses in adult Rufous-Collared Sparrow (Zonotrichia capensis), an omnivorous passerine that is ubiquitous in Chile and inhabits a wide range of environments. We acclimated birds to 30 days at two ambient temperatures (27 °C and 17 °C) and drinking water salinity (200 mM NaCl and fresh water) conditions. We evaluated: 1) the aerobic scope and the activities of mitochondrial metabolic enzymes, 2) osmoregulatory parameters, 3) the skin-swelling immune response to an antigen, 4) oxidative status, and 5) the length of telomeres of red blood cells. Our results confirm that Z. capensis tolerates the chronic consumption of moderate levels of salt, maintaining body mass but increasing their basal metabolic rates consistent with expected osmoregulatory costs. Additionally, the factorial aerobic scope was higher in birds acclimated to fresh (tap) water at both 17° and 27 °C. Drinking water salinity and low ambient temperatures negatively impacted inflammatory response, and we observed an increase in lipid peroxidation and high levels of circulating antioxidants at low temperatures. Finally, telomere length was not affected by osmo- and thermoregulatory stress. Our results did not support the existence of an interplay between environmental temperature and drinking water salinity on most physiological and biochemical traits in Z. capensis, but the negative effect of these two factors on the inflammatory immune response suggests the existence of an energetic trade-off between biological functions that act in parallel to control immune function.
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Intraspecific variation in exploratory behavior and elevational affinity in a widely distributed songbird
Oecologia, 2018Co-Authors: Yanina Poblete, Víctor Gutiérrez, Seth D. Newsome, Pablo Sabat, Rodrigo A. VásquezAbstract:Populations of the same species can vary substantially in their behavioral and morphometric traits when they are subject to different environmental pressures, which may lead to the development of different adaptive strategies. We quantified variation in exploratory behavior and morphometric traits among two Rufous-Collared Sparrow populations that occur at low and high elevations in central Chile. Moreover, we used census and δ^2H values of feather and blood to evaluate migration. We found that individual Sparrows inhabiting high elevations were larger and showed more intense exploratory behavior in comparison with those that were captured at lower elevation. Moreover, we observed a steady decline in Sparrow abundance during the winter and similar δ^2H values for blood collected in the winter and summer at this site, which were significantly lower than blood δ^2H values observed at low elevation. This pattern suggests that individuals do not move long distances during winter, and likely they remain at similar elevations in refuge habitats. As predicted, our results support the existent of different adaptive strategies among populations of the same species, and suggest that the combination of behavioral, morphometric, and stable isotope data is a novel and robust integrative approach to assess differences in adaptation across environmental gradients.
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coping with salt water habitats metabolic and oxidative responses to salt intake in the rufous collared Sparrow
Frontiers in Physiology, 2017Co-Authors: Seth D. Newsome, Pablo Sabat, Roberto F. Nespolo, Karin Maldonado, Cristobal Narváez, Isaac Penavillalobos, Carolina Contreras, Juan C Sanchezhernandez, Francisco BozinovicAbstract:Many physiological adjustments occur in response to salt intake in several marine taxa, which manifest at different scales from changes in the concentration of individual molecules to physical traits of whole organisms. Little is known about the influence of salinity on the distribution, physiological performance, and ecology of passerines; specifically, the impact of drinking water salinity on the oxidative status of birds has been largely ignored. In this study, we evaluated whether experimental variations in the salt intake of a widely-distributed passerine (Zontotrichia capensis) could generate differences in basal (BMR) and maximum metabolic rates (Msum), as well as affect metabolic enzyme activity and oxidative status. We measured rates of energy expenditure of birds after 30-d acclimation to drink salt (SW) or tap (fresh) water (TW) and assessed changes in the activity of mitochondrial enzymes (cytochrome c oxidase and citrate synthase) in skeletal muscle, heart, and kidney. Finally, we evaluated the oxidative status of bird tissues by means of total antioxidant (TAC) and superoxide dismutase activities and lipid oxidative damage (Malondialdehyde, MDA). The results revealed a significant increase in BMR but not Msum, which resulted in a reduction in factorial aerobic scope in SW- versus TW-acclimated birds. These changes were paralleled with increased kidney and intestine masses and catabolic activities in tissues, especially in pectoralis muscle. We also found that TAC and MDA concentrations were ~120% and ~400% higher respectively in the liver of animals acclimated to the SW- versus TW-treatment. Our study is the first to document changes in the oxidative status in birds that persistently drink saltwater, and shows that they undergo several physiological adjustments that range that range in scale from biochemical capacities (e.g., TAC and MDA) to whole organism traits (e.g., metabolic rates). We propose that the physiological changes observed in Z. capensis acclimated to saltwater could be common phenomena in birds and likely explain selection of prey containing little salt and habitats associated with low salinity.
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Coping with Salt Water Habitats: Metabolic and Oxidative Responses to Salt Intake in the Rufous-Collared Sparrow
Frontiers in physiology, 2017Co-Authors: Pablo Sabat, Seth D. Newsome, Roberto F. Nespolo, Karin Maldonado, Isaac Peña-villalobos, Juan C. Sanchez-hernandez, Cristobal Narváez, Carolina Contreras, Francisco BozinovicAbstract:Many physiological adjustments occur in response to salt intake in several marine taxa, which manifest at different scales from changes in the concentration of individual molecules to physical traits of whole organisms. Little is known about the influence of salinity on the distribution, physiological performance, and ecology of passerines; specifically, the impact of drinking water salinity on the oxidative status of birds has been largely ignored. In this study, we evaluated whether experimental variations in the salt intake of a widely-distributed passerine (Zontotrichia capensis) could generate differences in basal (BMR) and maximum metabolic rates (Msum), as well as affect metabolic enzyme activity and oxidative status. We measured rates of energy expenditure of birds after 30-d acclimation to drink salt (SW) or tap (fresh) water (TW) and assessed changes in the activity of mitochondrial enzymes (cytochrome c oxidase and citrate synthase) in skeletal muscle, heart, and kidney. Finally, we evaluated the oxidative status of bird tissues by means of total antioxidant capacity (TAC) and superoxide dismutase activities and lipid oxidative damage (Malondialdehyde, MDA). The results revealed a significant increase in BMR but not Msum, which resulted in a reduction in factorial aerobic scope in SW- vs. TW-acclimated birds. These changes were paralleled with increased kidney and intestine masses and catabolic activities in tissues, especially in pectoralis muscle. We also found that TAC and MDA concentrations were ~120 and ~400% higher, respectively in the liver of animals acclimated to the SW- vs. TW-treatment. Our study is the first to document changes in the oxidative status in birds that persistently drink saltwater, and shows that they undergo several physiological adjustments that range that range in scale from biochemical capacities (e.g., TAC and MDA) to whole organism traits (e.g., metabolic rates). We propose that the physiological changes observed in Z. capensis acclimated to saltwater could be common phenomena in birds and likely explain selection of prey containing little salt and habitats associated with low salinity.
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Energetic costs and implications of the intake of plant secondary metabolites on digestive and renal morphology in two austral passerines
Journal of Comparative Physiology B, 2016Co-Authors: Gonzalo Barceló, Juan Manuel Ríos, Karin Maldonado, Pablo SabatAbstract:Seed-eating birds have a diet of high nutritional value; however, they must cope with plant secondary metabolites (PSM). We postulated that the detoxification capacity of birds is associated with a metabolic cost, given that the organs responsible for detoxification significantly contribute to energetic metabolism. We used an experimental approach to assess the effects of phenol-enriched diets on two passerines with different feeding habits: the omnivorous Rufous-Collared Sparrow ( Zonotrichia capensis ) and the granivorous common diuca-finch ( Diuca diuca ). The birds were fed with one of three diets: control diet, supplemented with tannic acid, or supplemented with Opuntia ficus - indica phenolic extract (a common food of the Sparrow but not the finch). After 5 weeks of exposure to the diets, we measured basal metabolic rates (BMR), energy intake, glucuronic acid output and digestive and kidney structure. In both species, detoxification capacity expressed as glucuronic acid output was higher in individuals consuming phenol-enriched diets compared to the control diet. However, whereas Sparrows increase energy intake and intestinal mass when feeding on phenol-enriched diets, finches had lower intestinal mass and energy intake remains stable. Furthermore, Sparrows had higher BMR on phenol-enriched diets compared to the control group, whereas in the finches BMR remains unchanged. Interspecific differences in response to phenols intake may be determined by the dietary habits of these species. While both species can feed on moderate phenolic diets for 5 weeks, energy costs may differ due to different responses in food intake and organ structure to counteract the effects of PSM intake.
Daniel González-acuña - One of the best experts on this subject based on the ideXlab platform.
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Spatial distribution, prevalence and diversity of haemosporidians in the Rufous-Collared Sparrow, Zonotrichia capensis
Parasites & Vectors, 2019Co-Authors: Daniela Doussang, Luis Gonzalo Torres-fuentes, Rute Beatriz Clemente-carvalho, Kian Connelly Greene, Daniel González-acuña, Stephen C. Lougheed, Juliana A ViannaAbstract:Background Parasite prevalence and diversity are determined by the distribution of hosts and vectors and by the interplay among a suite of environmental factors. Distributions of parasite lineages vary based on host susceptibility and geographical barriers. Hemoparasites of the genera Haemoproteus and Plasmodium have wide distributions, and high prevalence and genetic diversity within perching birds (Order Passeriformes). The Rufous-Collared Sparrow ( Zonotrichia capensis ) is widely distributed in Central and South America across an immense diversity of environments from sea level to more than 4000 meters above sea level. It therefore provides an excellent model to investigate whether altitudinal and latitudinal gradients influence the distribution, prevalence and diversity of haemosporidian parasites, their population structure and the biogeographical boundaries of distinct parasite lineages. Results We assembled samples from 1317 Rufous-Collared Sparrows spanning 75 locales from across Central and South America (between 9.5°N and 54°S; 10–4655 meters above sea level). We used DNA sequence data from a fragment of the mitochondrial cytochrome b gene ( cytb ) of Haemoproteus and Plasmodium from 325 positive samples and found prevalences of 22 and 3%, respectively. Haemoproteus exhibited a higher prevalence than Plasmodium but with comparatively lower genetic diversity. We detected a relationship of Plasmodium and Haemoproteus prevalence with altitude and latitude; however, altitude and latitude did not influence parasite diversity. Conclusions Parasite lineages showed a phylogeographical boundary coincident with the Andes Mountains, although we also observed a north-south disjunction in Peru for Haemoproteus . Haemosporidian distribution was not homogeneous but differed based on latitude and altitude. This is most probably due to environmental factors that have influenced both vector distribution and abundance, as well as parasite development. Our study provides key insights on the distribution of haemoparasite lineages and parasite dynamics within hosts.
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Spatial distribution, prevalence and diversity of haemosporidians in the Rufous-Collared Sparrow, Zonotrichia capensis
Parasites & vectors, 2019Co-Authors: Daniela Doussang, Luis Gonzalo Torres-fuentes, Rute Beatriz Clemente-carvalho, Kian Connelly Greene, Daniel González-acuña, Stephen C. Lougheed, Juliana A ViannaAbstract:Parasite prevalence and diversity are determined by the distribution of hosts and vectors and by the interplay among a suite of environmental factors. Distributions of parasite lineages vary based on host susceptibility and geographical barriers. Hemoparasites of the genera Haemoproteus and Plasmodium have wide distributions, and high prevalence and genetic diversity within perching birds (Order Passeriformes). The Rufous-Collared Sparrow (Zonotrichia capensis) is widely distributed in Central and South America across an immense diversity of environments from sea level to more than 4000 meters above sea level. It therefore provides an excellent model to investigate whether altitudinal and latitudinal gradients influence the distribution, prevalence and diversity of haemosporidian parasites, their population structure and the biogeographical boundaries of distinct parasite lineages. We assembled samples from 1317 Rufous-Collared Sparrows spanning 75 locales from across Central and South America (between 9.5°N and 54°S; 10–4655 meters above sea level). We used DNA sequence data from a fragment of the mitochondrial cytochrome b gene (cytb) of Haemoproteus and Plasmodium from 325 positive samples and found prevalences of 22 and 3%, respectively. Haemoproteus exhibited a higher prevalence than Plasmodium but with comparatively lower genetic diversity. We detected a relationship of Plasmodium and Haemoproteus prevalence with altitude and latitude; however, altitude and latitude did not influence parasite diversity. Parasite lineages showed a phylogeographical boundary coincident with the Andes Mountains, although we also observed a north-south disjunction in Peru for Haemoproteus. Haemosporidian distribution was not homogeneous but differed based on latitude and altitude. This is most probably due to environmental factors that have influenced both vector distribution and abundance, as well as parasite development. Our study provides key insights on the distribution of haemoparasite lineages and parasite dynamics within hosts.
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Additional file 5: of Spatial distribution, prevalence and diversity of haemosporidians in the Rufous-Collared Sparrow, Zonotrichia capensis
2019Co-Authors: Daniela Doussang, Luis Gonzalo Torres-fuentes, Rute Beatriz Clemente-carvalho, Daniel González-acuña, Stephen C. Lougheed, Kian Greene, Juliana ViannaAbstract:Table S4. Pairwise Fst values calculated from mtDNA Haemoproteus sequences between countries and geographical areas of Chile. (DOCX 45 kb
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External and gastrointestinal parasites of the Rufous-Collared Sparrow Zonotrichia capensis (Passeriformes, Emberizidae) in Chile.
Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia , 2017Co-Authors: Sebastián Llanos-soto, Braulio Muñoz, Lucila Moreno, Carlos Landaeta-aqueveque, John Mike Kinsella, Sergey Mironov, Armando Cicchino, Carlos Barrientos, Gonzalo Torres-fuentes, Daniel González-acuñaAbstract:A total of 277 Rufous-Collared Sparrows, Zonotrichia capensis Muller, 1776 (Emberizidae), were examined for external parasites. The birds were captured using mist nets in seven locations in northern and central Chile. Additionally, seven carcasses from central Chile (the Biobio region) were necropsied to evaluate the presence of endoparasite infection. Ectoparasites were found on 35.8% (99/277) of the examined birds and they were represented by the following arthropods: feather mites Amerodectes zonotrichiae Mironov and Gonzalez-Acuna, 2014 (Analgoidea: Proctophyllodidae), Proctophyllodes polyxenus Atyeo and Braasch, 1966 (Analgoidea: Proctophyllodidae), and Trouessartia capensis Berla, 1959 (Analgoidea: Trouessartiidae); a louse Philopterus sp. (Phthiraptera: Ischnocera); and ticks Amblyomma tigrinum Koch, 1844 (Acari: Ixodidae) and Ixodes auritulus Neumann, 1904 (Acari: Ixodidae). Two of the seven necropsied carcasses were infected with the acanthocephalan Mediorhynchus papillosus Van Cleave, 1916 (Gigantorhynchida: Gigantorhynchidae). To our knowledge, this study reports P. polyxenus, Philopterus sp., A. tigrinum, and M. papillosus for the first time for Z. capensis and expands the distributional range for T. capensis to Chile.
