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The Amazon and Atlantic forests harbour immense biodiversity shaped by complex evolutionary history with diverse processes leading to species build‐up. We investigated the Cinereous Antshrike species complex ( Thamnomanes caesius and T. schistogynus ) to disentangle the relative contributions of riverine barriers and historical climatic fluctuations to diversification, using large specimen sampling across their entire distribu...
South American savannas are a disjunct biome with an unclear evolutionary history. We tested hypotheses about their Quaternary history and the evolution of savanna cores through fragmentation or dispersal from the Cerrado. We used genomic data (genotyping‐by‐sequencing) and ecological niche models of the Burnished‐buff Tanager ( Stilpnia cayana Linnaeus 1766) to evaluate intraspecific differentiation, gene flow, past range shi...
Aim The Amazon rainforest is one of the most biodiverse regions on earth, but our understanding of the processes that have shaped its patterns of diversity remains incomplete. One hypothesis for Amazonian speciation is the river‐refuge hypothesis, which suggests that retraction of forests away from the periphery of Amazonia, where rivers are narrow, facilitated divergence of populations separated by wide rivers. Later re‐expan...
The Caatinga is the largest patch of Seasonal Dry Tropical Forest in the Neotropics, located in northeastern Brazil and characterized mainly by deciduous vegetation and extreme rainfall seasonality. It has historically been treated as a biologically impoverished domain, but recent studies uncovered new diversification patterns and several new taxa of frogs, mammals, insects, and fishes. Here we employed a dense sampling regime...
Giants of the Amazon: How does environmental variation drive the diversity patterns of large trees?NARA Subscribed
For more than three decades, major efforts in sampling and analyzing tree diversity in South America have focused almost exclusively on trees with stems of at least 10 and 2.5 cm diameter, showing highest species diversity in the wetter western and northern Amazon forests. By contrast, little attention has been paid to patterns and drivers of diversity in the largest canopy and emergent trees, which is surprising given these h...
Amazonian birds in more dynamic habitats have less population genetic structure and higher gene flowNARA Subscribed
Understanding the factors that govern variation in genetic structure across species is key to the study of speciation and population genetics. Genetic structure has been linked to several aspects of life history, such as foraging strategy, habitat association, migration distance, and dispersal ability, all of which might influence dispersal and gene flow. Comparative studies of population genetic data from species with differi...
On species concepts, species delimitation criteria, taxonomy committees, and biases: a response to Lima (2022a)NARA Subscribed
In a recent commentary, Lima (Ornithol Res 30:225–228, 2022a) claims that the Brazilian Ornithological Records Committee (CBRO) bases its species ranking decisions on a misinterpretation of the general lineage species concept (GLSC), with two major detrimental consequences: (1) misinform the Brazilian ornithological community about the nature of interspecific limits and (2) mislead the users of the CBRO checklist “…about the n...
Although vicariant processes are expected to leave similar genomic signatures among codistributed taxa, ecological traits such as habitat and stratum can influence genetic divergence within species. Here, we combined landscape history and habitat specialization to understand the historical and ecological factors responsible for current levels of genetic divergence in three species of birds specialized in seasonally flooded hab...
Aim The distribution and connectivity of floodplain environments along major Amazonian rivers changed considerably over time following physiographic and climatic events. However, how historical alteration in floodplain habitats affected endemic species' demography and diversification is not fully understood. We tested if historical demographic changes of populations occurring on the floodplains of a major Amazon Basin tributar...
Habitat association constrains population history in two sympatric ovenbirds along Amazonian floodplainsNARA Subscribed
Aim Amazonian floodplains include distinct types of seasonally flooded habitats, determined by the flooding regime and sedimentation dynamics. Some bird species prefer specific habitat types within the floodplains. To investigate whether distinct habitats are differentially affected by geologic and climatic history, we compare population history in a sympatric and closely related pair of ovenbird species with different habitat...
Genomic differentiation with gene flow in a widespread Amazonian floodplain‐specialist bird speciesNARA Subscribed
Aim Ecological, climatic and palaeogeographical processes drive biological diversification. However, the evolutionary outcomes of those mechanisms are complex and difficult to discriminate. Here, we test how alternative drivers affected connectivity along the Amazonian floodplains generating current patterns of population structure and diversity within the Striped Woodcreeper, a widespread bird species tied to forests seasonal...
Gene flow, genomic homogenization and the timeline to speciation in Amazonian manakinsNARA Subscribed
Phylogeographical studies of the most species‐rich region of the planet—the Amazon basin—have repeatedly uncovered genetically distinctive, allopatric lineages within currently named species, but understanding whether such lineages are reproductively isolated species is challenging. Here we harness the power of genome‐wide data sets together with detailed phylogeographical sampling to both characterize the number of unique lin...
Aim Biotic interchange, speciation and extinction processes drive biotas assembling. However, the evolutionary outcomes of those mechanisms are complex and difficult to discriminate. Here, we investigate how these processes affect avian diversification in tropical forest regions and test the relative roles of vicariant speciation and biotic interchange on the assemblage of Amazonian biota through the reconstruction of the biog...
Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species‐level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, includi...