In the face of an impending global biodiversity crisis, understanding the natural processes involved in the origin and maintenance of biological diversity is a crucial step toward the goal of preserving the genetic reservoirs and ecological stability of the planet. In Latin America, a region that combines the richest concentration of biological species and one of the highest rates of habitat destruction on earth, research aimed to identifying the origins of diversity has been extensive but the explanations have remained controversial. One the most historically powerful hypothesis, the "Pleistocene refugia hypothesis", which maintains that regions of high rainfall have functioned as centers of evolution and preservation of biological species, has been recently challenged by abundant paleoecological data. Therefore, the effectiveness of current conservation strategies with a focus on wet areas for the preservation of biodiversity has been cast into doubt. This project will t est the alternative hypothesis that regions of high geologic complexity have been important centers for the origin of species, at least in the case of mammals. The study will use the funnel-eared bat family (Natalidae) as a model group, given that these animals are among the most widespread mammal groups in the new world tropics that depend on geomorphologic surface features (caves, crevices) for their survival. A robust reconstruction of the evolutionary history (phylogeny) of Natalidae will test whether the evolution of this bat family has been tied to the historical availability and distribution of caves in the new world tropics, making possible, in turn, to test whether areas of high complexity in surface geology have functioned as centers of speciation for these bats. The phylogeny will be inferred by comparing morphological and genetic traits of species of natalids deposited in museum collections in the US and Latin America.
This project will be the first to test whether cave regions have functioned as centers of bat speciation in the New World, thus representing potentially important sources of species diversity in tropical America. If this hypothesis is supported by our findings, this study will have a significant impact in the design of future conservation strategies aimed to protect centers of biological evolution in Latin America, as important repositories of the genetic wealth of the planet. The study will also have a broader impact in the understanding of cave biogeography in general, not only in tropical America but also in other regions of the world rich in caves and cave fauna. At a local scale, it will detect geographically restricted species of funnel-eared bats that may risk extinction and will promote their conservation, particularly of those that range into economically important areas and provide crucial natural control to agricultural pests.
