EAGER: Chronological context of species loss in a Caribbean vertebrate community

Today’s biodiversity crisis is underscored by species loss at a rate many times higher than expected based on the fossil record. It is estimated that since 1500 CE about 61% of species extinctions and 37% of all critically endangered species have been confined to islands. Factors such as environmental variability and direct human impacts, such as habitat destruction and overhunting, are among the top threats to insular species.

Species losses caused by these increased pressures may disrupt biotic communities and affect their function in the long term. Understanding how these factors affect biodiversity and why some species survive while others become extinct is important to devise strong policies for biodiversity conservation in the face of environmental change. The aim of this research is to examine past and present changes in the island vertebrate communities of Hispaniola and Puerto Rico to investigate how species responded to different factors before and after the arrival of humans.

By combining data from well-preserved fossils and modern communities, this study will target the following questions: What is the timeline of change in each island community? Does species loss vary with the characteristics of each island? What members of each island community persist or were lost over time?

What factors contributed to species loss? The answers to these questions will provide an opportunity to contextualize losses and community change across time and learn from these processes to help mitigate biodiversity loss today. This research will train undergraduate students, many of whom are from underrepresented groups in science; promote local scientific literacy via outreach; and benefit society by providing information about biodiversity change.

Through a detailed chronological study of the changes in vertebrate communities, this project will provide a basis for predicting species responses to factors related to past environmental variability, human colonization history, and island and species characteristics. The primary focus will be on a comparative analysis of bat communities between islands, however fossilized remains of other vertebrates will also be quantified, in light of theoretical expectations of island biogeography.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.