Sérgio Furtado dos Reis

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The structure of mutualistic networks provides clues to processes shaping biodiversity [1-10]. Among them, interaction intimacy, the degree of biological association between partners, leads to differences in specialization patterns [4, 11] and might affect network organization [12]. Here, we investigated potential consequences of interaction intimacy for(More)
The computationally challenging problem of reconstructing the phylogeny of a set of contemporary data, such as DNA sequences or morphological attributes, was treated by an extended version of the neighbor-joining (NJ) algorithm. The original NJ algorithm provides a single-tree topology, after a cascade of greedy pairing decisions that tries to(More)
In this paper, we present a new shape analysis approach using the well-known wavelet transform and exploring shape representation by landmarks. First, we describe the approach adopted to represent the landmarks data as parametric signals. Then, we show the relation of the derivatives of Gaussian wavelet transform applied to the signal-to-differential(More)
This paper presents the main steps to reconstruct phylogenetic trees using an evolutionary algorithm with a wide range of alternative computational procedures for fitness evaluation and for tuning the search engine. Due to the fine equilibrium between exploration and exploitation of the search space, high-quality reconstructions are obtained among an(More)
Individual-level diet variation can be easily quantified by gut-content analysis. However, because gut contents are a 'snapshot' of individuals' feeding habits, such cross-sectional data can be subject to sampling error and lead one to overestimate levels of diet variation. In contrast, stable isotopes reflect an individual's long-term diet, so isotope(More)
—Birds that remove ectoparasites and other food material from their hosts are iconic illustrations of mutualistic– commensalistic cleaning associations. To assess the complex pattern of food resource use embedded in cleaning interactions of an assemblage of birds and their herbivorous mammal hosts in open habitats in Brazil, we used a network approach that(More)
The correlation between morphological or molecular descriptors and the evolutive process is one of the main questions in morphometric analysis, which can be addressed in phylogenetic or environmental terms. In this context, many works have been presented to the scientific community having as main key the relation between phenotype and predetermined(More)
Poecilia vivipara is a small fish found throughout the coastal lowlands of South America. We report the isolation and characterization of 25 microsatellite loci in this tropical fish. In 24 individuals from two populations, 18 loci were polymorphic. The loci had 2–12 alleles, expected heterozygosities of 0.194–0.836, observed heterozygosities of(More)
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