We study the impact of climatic change on plant communities in tropical Central and South America. Successful conservation of tropical biodiversity requires that we understand the mechanisms controlling habitat and species distributions. Two potent forces induce changes in these distributions: climate change and human activities. My research uses paleoecology to understand the changing patterns of tropical biodiversity.
Through the study of fossil pollen, and charcoal, we reconstruct the history of habitats in tropical South America. These paleoecological records allow us to reconstruct climate change over the last 200,000 years and relate it to patterns of biodiversity, speciation, and human occupation. From these observations we contribute to the current debate on global climate change and species conservation.
To gain these data we must locate and visit ancient lakes in the neotropics. The lake sediments hold a history of the surrounding landscape since the formation of the lake. A core of those sediments provides us with a complete history of that location. We raise the cores using a backpackable coring rig. As many of these lakes lie in some of the most remote locations on Earth, the fieldwork is arduous and not for the faint-hearted. Although the coring is an important and exciting facet of our work, the great majority of our time is spent in intensive laboratory work counting and identifying fossil pollen, charcoal, diatoms and statistically analyzing the resultant data.
Our principal goal over the next few years will be to improve the taxonomic resolution of our pollen analyses and to raise new sediment cores that will allow us to test hypotheses of climate change. Our work is funded by grants from the National Science Foundation, NOAA, Moore Foundation.