This research, with work completed earlier, will provide a detailed analysis of the paleoecology of Cenozoic Central America using a series of fossil beds that are extremely rich in pollen. Cores will be sampled from each of two sites---one in southern Mexico and one on Puerto Rico. This study will complement data collected from other sites in the Caribbean and Isthmus regions. The data and the derived inferences will have great implications for understanding the effect of large-scale global change on the dynamics of vegetation, and the effects of those changes on animal populations and climate itself. Specifically, the results will be instrumental in understanding the origin and migration of floras during the closure of the Pan-American land mass. This event is crucial to comprehending the modern floras and faunas of the New World, and it has significance for biogeography, systematics, ecology, etc.
