Ecological studies with standardized sampling conducted on a large scale can provide an
understanding of patterns and processes hitherto unknown in the structuring of megadiverse
assemblages such as those from the Neotropics. In this thesis we present an analysis based on
multiple sampling sites installed along a transect of approximately 1,000 km, in the Purus-
Madeira interfluve and on the banks of the Upper Madeira River, in order to understand the
distribution of the lizard assemblages of this region. In the first chapter we characterized the
composition and abundance of the lizard assemblage in 10 sampling modules along the BR-
319 highway. We counted 25 taxa belonging to eight families, distributed heterogeneously
along the interfluve. We also we emphasize the importance of faunal surveys for future
conservation measures of the species of lizards of interfluvial regions in face of the increasing
anthropic impact in Amazonia. In the second chapter we evaluated how the environmental
heterogeneity, mainly associated with the Open and Dense Ombrophilous Forests of the region
of the Purus-Madeira interfluve forms the lizard assemblages. For this, we quantified the
assemblies through taxonomic and functional measures in fourteen sampling modules. We
observed that environmental factors such as soil, vegetation and rainfall vary in biogeographic
scale along the interfluve and influence the pattern of occurrence of species and functional
richness of the assemblages. Thus, we detected a large-scale species substitution pattern shaped
by the influence of environmental filters. In the third chapter we investigated, at different
scales, the influence of historical and ecological factors in the structure of lizard assemblages
in the region of the upper Madeira River. For this, 83 plots were sampled along the east and
west banks of the river. At the regional level, the upper Madeira River acts as a biogeographic
barrier to 29.6% of the species. In contrast, the performance of environmental filters explains
the structure of the assemblages at a local scale. This study, which pioneered such a wide
geographic scale in the ecology of Amazonian lizards, suggests that historical and ecological
factors have hierarchical effects in determining the spatial structuring of assemblages. Such as
the present investigation, future research addressing different scales according to standardized
sampling methods promises to elucidate processes and patterns related to the heterogeneous
spatial distribution of Amazonian biodiversity.
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