MORFOLOGIA DE GIRINOS DE POÇAS TEMPORÁRIAS EM ÁREAS DE TRANSIÇÃO CERRADO-AMAZÔNIA.

Abstract

The aim of this study was to investigate the morphological variation of anuran tadpoles from Maranhão state areas and associate the external morphology of the study group with aspects of species ecology at both community and population levels. In order to meet this goal, this thesis was divided into 03 chapters. In the first part, we describe aspects of the ecology and morphology of the species studied. In the second, we tested the community-level hypotheses of differences in morphological space between communities and between species. Also in this chapter, we test the relationship between the morphological space and aspects of species ecology. Regarding the comparison of the morphological space between communities, we observed a similar grouping of the species, pointing to a redundant organization pattern between the ponds regarding the morphological space. Regarding the comparison between species, it was observed that they differ from each other in external morphology. Two aspects of tadpole ecology were associated with the morphological space of the species: their position in the water column and the type of ecomorphological guild to which the species belongs. In the third part, we tested the hypothesis at the population level, where we compared the morphology of different populations for two tadpole species (Dendropsophus nanus and D. minutus) and associate the morphological space with spatial characteristics of the pond. We found morphometric differences in population-level for both species studied indicating the existence of geographic variation. The morphological space of the species was associated with the type of the specific environmental condition explored by the species. Because, in D. nanus, a bottom species, the morphology correlated with the Substrate, while the morphology in D. minutus, a mid-water species, it was associated with Internal Pond Vegetation. As a general conclusion, morphological variation was observed for anuran larvae only at species and population level. The results found here also point out that the use of the space niche (e.g. position in the water column) is an important aspect of species ecology in the existence of morphological variation at both community and population levels.