ABSTRACT
Incomplete speciation can be leveraged to associate phenotypes with genotypes, thus providing insights into the traits relevant to the reproductive isolation of diverging taxa. We investigate the genetic underpinnings of the phenotypic differences between Sporophila plumbea and Sporophila beltoni. Sporophila beltoni has only recently been described based, most notably, based on differences in bill coloration (yellow vs. black in S. plumbea). Both species are indistinguishable through mtDNA or reduced-representation genomic data, and even whole-genome sequencing revealed low genetic differentiation. Demographic reconstructions attribute this genetic homogeneity to gene flow, despite divergence in the order of millions of generations. We found a narrow hybrid zone in southern Brazil where genetically, yet not phenotypically, admixed individuals appear to be prevalent. Despite the overall low genetic differentiation, we identified 3 narrow peaks along the genome with highly differentiated SNPs. These regions harbor 6 genes, one of which is involved in pigmentation (EDN3) and is a candidate for controlling bill color. Within the outlier peaks, we found signatures of resistance to gene flow, as expected for islands of speciation. Our study shows how genes related to coloration traits are likely involved in generating prezygotic isolation and establishing species boundaries early in speciation.
Subject(s)
Gene Flow , Genetic Speciation , Pigmentation , Pigmentation/genetics , Brazil , Genomic Islands , Animals , Reproductive Isolation , Phenotype , Polymorphism, Single NucleotideABSTRACT
We report 4 highly pathogenic avian influenza A(H5N1) clade 2.3.4.4.b viruses in samples collected during June 2023 from Royal terns and Cabot's terns in Brazil. Phylodynamic analysis revealed viral movement from Peru to Brazil, indicating a concerning spread of this clade along the Atlantic Americas migratory bird flyway.
Subject(s)
Charadriiformes , Influenza A Virus, H5N1 Subtype , Influenza in Birds , Influenza, Human , Animals , Humans , Influenza in Birds/epidemiology , Animals, Wild , Brazil/epidemiology , Birds , PhylogenyABSTRACT
The general assumption that the survival patterns of tropical and southern temperate birds are similar lacks empirical data from higher latitudes. Regional comparisons of New World species are rare, and this assumption has been based on data from African studies. Here, we estimate the survival rates of 88 tropical and southern temperate bird populations (69 species) from eight localities in South America to evaluate the hypothesis that the survival of these populations is homogeneous at the regional scale. We estimated survival based on the Cormack-Jolly-Seber model and compared values from different environments. The survival estimates ranged from 0.30 to 0.80 (0.56 ± 0.12). Apparent survival did not differ significantly between low-latitude tropical environments (03°S) and the other sites from high-latitudes (between 22° and 34°S). Despite a predicted positive trend, body size was not significantly related to survival among passerines. On the other hand, phylogenetic relationships explained more than a third of the variation in bird survival. Based on the largest available database on South American bird species, our findings support the hypothesis that bird survival is homogeneous, at the regional scale, along the southern hemisphere. In particular, we reinforce the hypothesis that climatic variation has a limited influence on bird survival in the southern hemisphere.
Subject(s)
Tropical Climate , Phylogeny , South America , Body SizeABSTRACT
Information on the breeding biology of birds is essential for improving avian life-history theory and implementing sound management and conservation actions for these organisms. Comprehensive reviews of this kind of information are lacking for most Neotropical regions, including Rio Grande do Sul, the southernmost Brazilian state. Aiming to update the knowledge on the reproductive status of birds in Rio Grande do Sul, we reviewed breeding records of all potential breeding species recorded in the state using a set of predefined, restrictive criteria for accepting breeding evidences as effective. Data satisfying our criteria were available for 165 species in the literature. We also collected novel breeding information obtained in the state for an additional 126 species, including observations for several species whose reproductive biology is poorly known. Among these are birds previously unknown to breed in Brazil. This new data and the critical review of the previous information resulted in a total of 291 species for which breeding evidences are accepted as effective. This corresponds to 54.7% of the 532 species considered either confirmed or potential breeders in the state. In addition to providing information on nesting dates, clutch size, nest architecture and breeding behavior of south Brazilian birds, our review serves as a benchmark for the adequate assessment of avian breeding records elsewhere. We hope to stimulate observers to rigorously document breeding events, especially for taxa for which basic information is lacking.(AU)
Informações sobre a biologia reprodutiva das aves são essenciais para aprimorar estudos teóricos sobre a história natural do grupo e implementar ações de manejo e conservação efetivas para esses organismos. Não existem revisões abrangentes sobre o tema para a maioria das regiões neotropicais, incluindo o Rio Grande do Sul, o estado mais meridional do Brasil. Com o objetivo de atualizar o conhecimento sobre o status reprodutivo das aves no Rio Grande do Sul, analisamos os registros reprodutivos de todas as espécies de aves que potencialmente se reproduzem no estado utilizando um conjunto de critérios pré-definidos e restritivos para avaliar a efetividade das evidências reprodutivas. Dados que satisfazem nossos critérios foram encontrados para 165 espécies na literatura. Também compilamos registros de reprodução inéditos obtidos no estado para outras 126 espécies, incluindo observações sobre diversas espécies cuja biologia reprodutiva é pouco conhecida. Entre elas estão espécies cuja reprodução no Brasil era até então desconhecida. Esses novos dados, em conjunto com a revisão crítica dos registros prévios, resultaram em um total de 291 espécies para as quais existem evidências de reprodução efetivas, o que corresponde a 54,7% das 532 espécies que efetiva ou potencialmente se reproduzem no estado. Além de fornecer informações sobre datas de nidificação, tamanho de postura ou prole, arquitetura de ninhos e comportamento reprodutivo das aves do sul do Brasil, nossa análise serve como referência para a avaliação adequada de registros de reprodução de aves em outras regiões. Esperamos estimular observadores a documentar rigorosamente eventos reprodutivos, especialmente para táxons que carecem de informações básicas.(AU)
Subject(s)
Animals , Birds/anatomy & histology , Birds/metabolism , Birds/physiology , Reproductive BehaviorABSTRACT
Information on the breeding biology of birds is essential for improving avian life-history theory and implementing sound management and conservation actions for these organisms. Comprehensive reviews of this kind of information are lacking for most Neotropical regions, including Rio Grande do Sul, the southernmost Brazilian state. Aiming to update the knowledge on the reproductive status of birds in Rio Grande do Sul, we reviewed breeding records of all potential breeding species recorded in the state using a set of predefined, restrictive criteria for accepting breeding evidences as effective. Data satisfying our criteria were available for 165 species in the literature. We also collected novel breeding information obtained in the state for an additional 126 species, including observations for several species whose reproductive biology is poorly known. Among these are birds previously unknown to breed in Brazil. This new data and the critical review of the previous information resulted in a total of 291 species for which breeding evidences are accepted as effective. This corresponds to 54.7% of the 532 species considered either confirmed or potential breeders in the state. In addition to providing information on nesting dates, clutch size, nest architecture and breeding behavior of south Brazilian birds, our review serves as a benchmark for the adequate assessment of avian breeding records elsewhere. We hope to stimulate observers to rigorously document breeding events, especially for taxa for which basic information is lacking.
Informações sobre a biologia reprodutiva das aves são essenciais para aprimorar estudos teóricos sobre a história natural do grupo e implementar ações de manejo e conservação efetivas para esses organismos. Não existem revisões abrangentes sobre o tema para a maioria das regiões neotropicais, incluindo o Rio Grande do Sul, o estado mais meridional do Brasil. Com o objetivo de atualizar o conhecimento sobre o status reprodutivo das aves no Rio Grande do Sul, analisamos os registros reprodutivos de todas as espécies de aves que potencialmente se reproduzem no estado utilizando um conjunto de critérios pré-definidos e restritivos para avaliar a efetividade das evidências reprodutivas. Dados que satisfazem nossos critérios foram encontrados para 165 espécies na literatura. Também compilamos registros de reprodução inéditos obtidos no estado para outras 126 espécies, incluindo observações sobre diversas espécies cuja biologia reprodutiva é pouco conhecida. Entre elas estão espécies cuja reprodução no Brasil era até então desconhecida. Esses novos dados, em conjunto com a revisão crítica dos registros prévios, resultaram em um total de 291 espécies para as quais existem evidências de reprodução efetivas, o que corresponde a 54,7% das 532 espécies que efetiva ou potencialmente se reproduzem no estado. Além de fornecer informações sobre datas de nidificação, tamanho de postura ou prole, arquitetura de ninhos e comportamento reprodutivo das aves do sul do Brasil, nossa análise serve como referência para a avaliação adequada de registros de reprodução de aves em outras regiões. Esperamos estimular observadores a documentar rigorosamente eventos reprodutivos, especialmente para táxons que carecem de informações básicas.
Subject(s)
Animals , Birds/anatomy & histology , Birds/physiology , Birds/metabolism , Reproductive BehaviorABSTRACT
The genus Sporophila (Cabanis, 1844) unites about 30 species of small seedeaters that predominantly inhabit open or semi-open areas in the Neotropical region. The taxonomy of this group is based on morphological studies from collected male specimens. The dynamic spatial and temporal variation in the male plumage and lack of knowledge of their vocalizations make it difficult to properly diagnose some species even today, so these two aspects account for the existing taxonomic dilemmas involving Sporophila. During a four-year field study, we investigated the natural history of a breeding population of Sporophila melanogaster (Pelzeln, 1870). This is an endemic species in Brazil, which reproduces in the high-altitude grasslands of the Atlantic Forest biome. We found four male specimens with clearly diagnosable plumage, distinct from the typical form of the species. Here we describe this previously unreported plumage form. Based on the evaluation of habitat use, vocalization, and reproductive behavior, we tested two hypotheses regarding its taxonomic status. We concluded that this is another case of an intra-specific color morph within the seedeaters of the "capuchinos" group.
O gênero Sporophila (Cabanis, 1844) reúne cerca de 30 espécies de papa-capins de pequeno porte, que habitam predominantemente áreas abertas ou semi-abertas na região Neotropical. A taxonomia do gênero é baseada em estudos morfológicos de exemplares machos adultos coletados. A variação espaço-temporal dinâmica na coloração da plumagem dos machos e a falta de conhecimento sobre suas vocalizações torna difícil diagnosticar adequadamente algumas espécies, de modo que esses dois aspectos são responsáveis pelos dilemas taxonômicos envolvendo Sporophila. Durante quatro anos estudamos a história natural da população reprodutiva de Sporophila melanogaster (Pelzeln, 1870). Essa é uma espécie endêmica do Brasil, que reproduz em campos de altitude do bioma Mata Atlântica. Ao longo desse estudo foram encontrados quatro exemplares machos com plumagem claramente distinta da forma típica conhecida para a espécie. Aqui nós descrevemos essa nova forma, com base na avaliação do uso do hábitat, vocalização e comportamento reprodutivo, e testamos duas hipóteses em relação a sua situação taxonômica. Concluimos tratar-se de mais um morfo de coloração em Sporophila do grupo dos caboclinhos.
ABSTRACT
The genus Sporophila (Cabanis, 1844) unites about 30 species of small seedeaters that predominantly inhabit open or semi-open areas in the Neotropical region. The taxonomy of this group is based on morphological studies from collected male specimens. The dynamic spatial and temporal variation in the male plumage and lack of knowledge of their vocalizations make it difficult to properly diagnose some species even today, so these two aspects account for the existing taxonomic dilemmas involving Sporophila. During a four-year field study, we investigated the natural history of a breeding population of Sporophila melanogaster (Pelzeln, 1870). This is an endemic species in Brazil, which reproduces in the high-altitude grasslands of the Atlantic Forest biome. We found four male specimens with clearly diagnosable plumage, distinct from the typical form of the species. Here we describe this previously unreported plumage form. Based on the evaluation of habitat use, vocalization, and reproductive behavior, we tested two hypotheses regarding its taxonomic status. We concluded that this is another case of an intra-specific color morph within the seedeaters of the "capuchinos" group.
O gênero Sporophila (Cabanis, 1844) reúne cerca de 30 espécies de papa-capins de pequeno porte, que habitam predominantemente áreas abertas ou semi-abertas na região Neotropical. A taxonomia do gênero é baseada em estudos morfológicos de exemplares machos adultos coletados. A variação espaço-temporal dinâmica na coloração da plumagem dos machos e a falta de conhecimento sobre suas vocalizações torna difícil diagnosticar adequadamente algumas espécies, de modo que esses dois aspectos são responsáveis pelos dilemas taxonômicos envolvendo Sporophila. Durante quatro anos estudamos a história natural da população reprodutiva de Sporophila melanogaster (Pelzeln, 1870). Essa é uma espécie endêmica do Brasil, que reproduz em campos de altitude do bioma Mata Atlântica. Ao longo desse estudo foram encontrados quatro exemplares machos com plumagem claramente distinta da forma típica conhecida para a espécie. Aqui nós descrevemos essa nova forma, com base na avaliação do uso do hábitat, vocalização e comportamento reprodutivo, e testamos duas hipóteses em relação a sua situação taxonômica. Concluimos tratar-se de mais um morfo de coloração em Sporophila do grupo dos caboclinhos.
ABSTRACT
We studied stomachs contents of 50 specimens of four common cuckoo species (Cuculidae) from southern Brazil: Guira guira (Gmelin, 1788) (n = 21), Coccyzus melacoryphus (Vieillot, 1817) (n = 8), Crotophaga ani (Linnaeus, 1758) (n = 11), and Piaya cayana (Linnaeus, 1766) (n = 10). We measured stomach volume and prey were identified and quantified based in their dimensions. The size of the prey was associated with bill width and body mass. Diet items were analyzed and identified to the lowest possible taxonomic level, based on literature, scientific collection data, and specialists. The diet of the four species was composed by 100% animal species, with invertebrate dominance. Only in G. guira stomachs the presence of vertebrates was observed more than once (amphibian, reptile, and bird). C. ani, which had similar diet, ingested a large number of Arachnida and Orthoptera. Piaya cayana ate mostly Hemiptera. The predominance of caterpillars (Lepidoptera), suggested in the literature was not observed in the diet of C. melacoryphus. There was a statistically significant difference in bill width and body mass among the bird species, and there was no correlation between bill width and the proportion of medium and large-sized prey.
ABSTRACT
We studied stomachs contents of 50 specimens of four common cuckoo species (Cuculidae) from southern Brazil: Guira guira (Gmelin, 1788) (n = 21), Coccyzus melacoryphus (Vieillot, 1817) (n = 8), Crotophaga ani (Linnaeus, 1758) (n = 11), and Piaya cayana (Linnaeus, 1766) (n = 10). We measured stomach volume and prey were identified and quantified based in their dimensions. The size of the prey was associated with bill width and body mass. Diet items were analyzed and identified to the lowest possible taxonomic level, based on literature, scientific collection data, and specialists. The diet of the four species was composed by 100% animal species, with invertebrate dominance. Only in G. guira stomachs the presence of vertebrates was observed more than once (amphibian, reptile, and bird). C. ani, which had similar diet, ingested a large number of Arachnida and Orthoptera. Piaya cayana ate mostly Hemiptera. The predominance of caterpillars (Lepidoptera), suggested in the literature was not observed in the diet of C. melacoryphus. There was a statistically significant difference in bill width and body mass among the bird species, and there was no correlation between bill width and the proportion of medium and large-sized prey.