|Support type:||Scholarships in Brazil - Scientific Initiation|
|Effective date (Start):||March 01, 2012|
|Effective date (End):||December 31, 2012|
|Field of knowledge:||Biological Sciences - Ecology - Theoretical Ecology|
|Principal Investigator:||Fernando Rodrigues da Silva|
|Grantee:||Mariana Victorino Nicolosi Arena|
|Home Institution:||Centro de Ciências e Tecnologias para a Sustentabilidade (CCTS). Universidade Federal de São Carlos (UFSCAR). Sorocaba , SP, Brazil|
Until recently, one of the difficulties of understanding the factors determining the beta diversity was that ecological and historical processes were quite similar and statistically difficult to partition. However, Baselga (2010) published an approach that disentangles the beta diversity into two components: species turnover (change in species composition between local assemblies) and nestedness (loss of species in certain assemblages that result in a species composition that is a subset of the richest assemblages). In this study, we aim to disentangle the contribution of species turnover and nestedness patterns of amphibian beta diversity within two gradients (latitudinal and longitudinal) in the Brazilian Atlantic Forest. Our hypothesis is that different components are responsible for the pattern of beta diversity in each of the gradients. Assuming that amphibians is a group with low dispersal ability and known adaptations to environmental conditions of humidity and rainfall, we predict that the nestedness component will be the main determinant of beta diversity in the longitudinal gradient, because there is a huge difference in the climate condition (especially rainfall) between the Atlantic Rain Forest (east) and Semideciduous Forest (west). On the other hand, considering that the tropical forest retreat during the climate changes in the Quaternary formed stable coastal areas (refuge) during the Pleistocene, supporting high rates of speciation, we predict that the species turnover will be the main determinant of beta diversity in the gradient latitudinal, due to high rates of endemism. Therefore, we predict that the results of this work will contribute to the understanding of the processes (species turnover versus loss of species) that determine the distribution of species richness of amphibians in the Atlantic Forest, and consequently, will provide theoretical support for the conservation and management of the threatened biodiversity of this group.