Dados do Trabalho

Título

OF RIVERS AND PRIMATES: WHICH RIVERS DELIMIT THE DISTRIBUTION OF AMAZONIAN PRIMATES?

Resumo

<p>Amazonian rivers are barriers to the dispersal of some animals, in particular, those large and fast flowing rivers. Thus, a few large rivers form Areas of Endemism (AoE) where the distribution of many organism taxa is congruent. However, the extent to which primate distributions are affected by large rivers in Amazonia remains to be explicitly demonstrated. We compiled the distribution maps of most Amazonian primates to test the hypothesis that the main rivers that delimit the known AoE are effective barriers. For the hypothesis to hold, we need to find dissimilar communities between AoE. We used 83 of 92 primate distribution ranges available in the IUCN redlist website. We identified which species occurred in each AoE and calculated a Jaccard dissimilarity matrix. We used species dissimilarity between adjacent pairs of AoE in a multiple regression model to evaluate the effect of river width and annual discharge in primate geographic isolation. A cluster analysis was used to evaluate similarities among primate fauna occurring in the AoE. Fifty-four species (65%) were restricted to a single AoE. General mean dissimilarity was 0.87, ranging 0.50-0.97. Two large clusters emerged; formed by the western AoE (Rondônia, Inambari and Napo) and another coarsely formed by the eastern AoE (Guiana, Tapajós, Xingu and Belém) plus Imeri. Within the eastern cluster, two sub clusters stand out, one at the north and another at the south of the Amazonas River. Species dissimilarity in the AoE was positively correlated with annual discharge, but no correlation was found with river width. Thus, we show that rivers are strong enough barriers to delimit the distribution of Amazonian primate species to the main AoE. Molecular studies are necessary to investigate the role that rivers play as vicariant agents of speciation.</p>

Financiamento

<p>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior</p>

Palavras-chave

<p>biogeography; vicariance; Wallace's riverine barrier hypothesis</p>

Área

Área 1 - Ecologia