Processos ecológicos e filogenéticos na estruturação de comunidades de girinos

A história evolutiva das linhagens e as características ambientais são fatores conhecidos por influenciar a coexistência das espécies em uma comunidade. Ao longo da evolução, os atributos funcionais das espécies, que determinam a forma como as espécies utilizam os recursos, podem se diferenciar ou se manter semelhantes aos de seus ancestrais. As características abióticas promovem a seleção de espécies que possuam atributos que possibilitem sua sobrevivência sob um conjunto específico de condições ambientais. Nosso objetivo foi verificar se a ocorrência de girinos em poças está relacionada com as variáveis ambientais dos corpos d’água, o que indica a atuação de processos ecológicos como filtros ambientais ou competição, considerando as relações de parentesco entre as espécies. Esperamos que as diferenças nas características dos corpos d’água afetem os padrões de co-ocorrência de girinos e que espécies filogeneticamente próximas co- ocorram mais do que o esperado ao acaso. Amostramos girinos em 13 corpos d’águas lênticos no Parque Estadual da Serra do Mar – núcleo Picinguaba, entre setembro de 2011 e março de 2012. Testamos a influência do hidroperíodo dos corpos d’água, cobertura de dossel, temperatura e pH da água na co-ocorrência dos girinos. Inferimos a relação de parentesco entre os anuros presentes nas comunidades através de uma hipótese filogenética já proposta e obtivemos os comprimentos dos ramos em milhões de anos a partir das idades dos nós. Analisamos o efeito do ambiente e do parentesco sobre três padrões de co-ocorrência de espécies: agrupado, associado e mutuamente excludente. Nossos resultados indicam que as características dos corpos d’água influenciam fortemente a estruturação das comunidades de girinos. Nossos resultados demonstram que a influência...The evolutionary history of lineages and the environmental characteristics are factors known for influencing the species coexistence in a community. Along evolution, functional traits of species, which determine the way species use resources, can differ or remain similar to their ancestors. Abiotic characteristics promote selection of traits that allow survival under a set of environmental conditions. Our objective was to verify whether the co-occurrence of tadpoles in ponds is related to environmental variables of water bodies, what indicates either ecological processes as environmental filters or competition, or to relatedness among species. We expect that differences in characteristics of the ponds affect the co-occurrence patterns of tadpoles and also that related species co-occur more than expected at random. We sampled tadpoles in 13 ponds at Parque Estadual da Serra do Mar – núcleo Pincinguaba, between September of 2011 and March of 2012.We tested the influence of the hydroperiod of the ponds, the canopy cover, water temperature and pH in co-occurrence of tadpoles. We determinedrelatedness between anurans present in communities through an already proposed topology and obtained the length of branches in millions of years from the age of the nodes. We analyzed the effects of habitat and species relatedness on three possible patterns of species co-ocorrence: clumping, togetherness and checkerboard. Our results show that environmental filters have strong influence in structuring communities. The gradient of canopy cover, hydroperiod and pH seem to be important environmental filters in habitat selection of species with togetherness and checkerboard co-occurrence patterns. Also, we detected the co-occurrence of pairs of closely related species in ponds with distinct environmental characteristics, evidencing... (Complete abstract click electronic access below

Natural enemies depend on remnant habitat size in agricultural landscapes

In recent decades, the consequences of habitat fragmentation have been of growing concern, because it is particularly important to understand how fragmentation may affect biodiversity, an ecological service. We tested two hypotheses: (1) that natural fragment size in agricultural landscapes indirectly affects the herbivore through effects on natural predator populations; and (2) predator activity into the crop reduces along the distance from the natural fragment edge. From 2008 and 2009, we conducted our study in seven forest remnants and in surrounding coffee plantations (fragments ranged from 6 to 105 ha, mean 49.28 +/- A 36.60 ha) in Southern Minas Gerais, Brazil. Birds were sampled by point counts, and insect predation was evaluated by using an artificial insect model (Koh and Menge 2006). Our results suggest that although there were many potential predators (e.g., wasps, ants, birds, and mammals), birds were the most important taxon unit. The covariance analysis supported the hypothesis that patch size affected the number of larvae predation by overall taxi, but there was no support for a distance effect. These findings suggest that natural enemies'ecological service (mainly from birds) declined with remnant reduction, which has implications not only for human welfare, but also in strengthening the economic justifications for conserving the remaining natural habitats and biodiversity in agricultural landscapes.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Data from: Intraspecific and interspecific trait variability in tadpole metacommunities from the Brazilian Atlantic rainforest

1. A better understanding of species coexistence and community dynamics may benefit from more insights on trait variability at the individual and species levels. 2. Tadpole assemblages offer an excellent system to understand the relative influence of intra- and interspecific variability on community assembly, due to their high phenotypic plasticity, and the strong influence that environmental variables have on their spatial distribution and individual performance. 3. Here we quantified the intra- and interspecific components of tadpoles’ trait variability in order to investigate their relative role in shaping tadpole communities. 4. We selected eight functional traits related to microhabitat use, foraging strategies and swimming ability. We measured these traits on 678 individuals from 22 species captured in 43 ponds in the Atlantic Forest. We used single- and multi-trait analyses to decompose trait variability. To explore the action of external and internal filtering on community assembly, we used a variance decomposition approach that compares phenotypic variability at the individual, population, community and regional levels. 5. On average, 33% of trait variability was due to within species variation. This decomposition varied widely among traits. We found only a reduced effect of external filtering (low variation in the height of the ventral fin within ponds in comparison to the total variation), whereas the internal filtering was stronger than expected. Traits related to the use of different micro-habitats through the water column were generally less variable than traits related to swimming ability to escape of predators, with tail traits being highly variable within species. 6. Our study highlights the importance of incorporating both intra- and interspecific, trait differences and of focusing on a diversity of traits related to both stabilizing niche and fitness differences in order to better understand how trait variation relates to species coexistence

Knowledge gaps and bibliographical revision about descriptions of free-swimming anuran larvae from Brazil

Research on tadpole morphology has grown rapidly in recent decades, but many larval anurans remain unknown. We made a literature survey of all studies that describe free-swiming larvae of anuran species occurring in Brazil in order to identify major gaps and provide a searchable bibliographical source about these descriptions. We found that 61.25% of tadpoles of species with free-swiming larvae have already been described. We hope that this paper will foster future tadpole descriptions by providing easy access to the literature.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

data_Atlantic_Forest

Data of pond-dweeling tadpoles collected in 43 ponds from Atlantic Rain Forest (2011-2013) in four different localities (Ubatuba, Bertioga, Itanhaém, and Iguape municipalities) in São Paulo state, southeastern Brazil. A standadized protocol was used to measure XX morphological traits on 678 tadpoles from 22 anuran species. Abbreviations: estagio = tadpole developement stage; BCI = body compression index; RDE = Relative diameter of the eyes; HDF= Relative height of the dorsal fin; HVF = Relative height of the ventral fin; RWT = Relative width of the tail; TCI = Tail compression index; DNS = Distance from nares to snout; RDN = Relative diameter of the nares; Numb_species = species richness by pond; Numb_individuals = total abundance by pond; Minimum_individual_per_species = minimum number of individual per species by pond