Talk Title: "The origin of a biodiversity hotspot: changes in vertebrate communities during the late Cenozoic shaped modern Caribbean diversity"

The Caribbean islands have served as a model for establishing the baseline of our modern understanding of island biogeography and community ecology. These islands are considered biodiversity hotspots today, with high levels of local endemism often associated with large adaptive radiations. Previous work suggests that the ancestors of the regional fauna arrived via a transient land connection or overwater dispersal, evolved in isolation under relatively stable conditions, and experienced a biodiversity crisis in the late Quaternary, associated with multiple waves of extinctions. Using fossils from the late Neogene and Quaternary, we began to address how changes in biodiversity through time shaped the Caribbean hotspot. We found that diversity patterns today and in the late Quaternary in the region associated with oceanic islands are relatively recent, following a large-scale faunal overturn in the Pliocene and rejecting the stability hypothesis. Furthermore, using isotope ecology, we address how the functional diversity of mammalian vertebrate communities in the region was reduced during the Holocene and how these legacies persist in modern communities. This work highlights the value of deep-time ecological reconstructions for understanding extinction, ecological and biogeographical patterns, and informing conservation policies in insular regions worldwide undergoing rapid defaunation.