Biogeography and Macroecology
Andean biodiversity
The goal of this work is to develop mechanisms that can bring a large and rich data set on the status of the environment and climate measured by NASA’s Earth Observing System (EOS) to the biological and conservation community. Environmental variables such as surface heterogeneity, vegetation cover, amplitude and patterns of disturbance, moisture regimes, geological features, and climate variables are important in defining patterns of species distribution and biodiversity. The processes governing diversification, speciation, and habitat stability will be integrated in a geographical context such that these patterns can readily represent important areas for conservation. This will allow us to understand and quantify the threats resulting from climate change and human-induced stresses on biological patterns and processes. The specific objectives of are:
1. To develop a species distribution model that can incorporate remote sensing-detected or -derived environmental variables at various spatial and temporal scales.
2. To develop mechanisms that enable historical and evolutionary processes to be integrated with the distribution model in a spatial context.
3. To simulate the impacts of various climate and land use change scenarios on the distribution of both biotic patterns and processes.
Australian biodiversity
Both theoretical and empirical evidence suggest that historical biogeography and evolution have a strong influence on spatial variation in the richness and composition of species assemblages. At the same time, there is evidence that species respond individualistically to climate-driven changes in the distribution of suitable habitats. It follows that reconstruction of the historical demography of species provides an essential framework for interpreting patterns of assemblage structure across dynamic landscapes. To understand why different species vary in their response to a given history of habitat change and how this affects local richness and structure of species assemblages, we are combining multi-locus estimates of demographic structure with information on species’ ecology and with spatially explicit models of habitat and species history. This work relies on an integrated molecular and ecological approach to investigate the biogeographic history of amphibian and reptile species endemic to the rainforests of northeastern Australia.
Predicted distribution of wet forest at different paleoclimatic time slices are summed to create a stability surface. From this surface we can calculate predicted habitat stability (in terms of the probability of maintaining wet forest habitat to which most endemic species are restricted)
Global and Regional Biodiversity Projects
I am involved in a series of projects focused on integrating ecological data (niche modeling) with distributional, phylogenetic, behavioral and/or morphological data. As with the above biodiversity projects, these projects integrate data from several different sources to better understand the mechanisms influencing observed patterns of diversity.