Excellence in Research: Exploring the role of fruit-eating bats in the dispersal of plant pathogens and the escape hypothesis

This project will investigate how fruit-eating bats contribute to plant health and survival by dispersing seeds and reducing harmful microbes found in fruits. When bats eat fruits and later excrete the seeds, this natural process may help eliminate disease-causing organisms and improve how well seeds germinate and grow. The project will study these effects by collecting fruits and bat droppings in Costa Rica, then growing plants from the seeds in a greenhouse. The study will monitor the young plants over the course of a year, tracking their growth, health, and the communities of microorganisms living inside them. The findings will help explain how animal behavior influences plant development and long-term ecosystem health. In addition to advancing scientific knowledge, the project will provide valuable training for students through hands-on research in the field and laboratory. It will also help strengthen research programs at Bowie State University by supporting student learning, faculty development, and international collaboration. This project aims to test the hypothesis that the passage of seeds through frugivorous bat guts influences plant fitness by altering the phytobiome and reducing fruit-associated plant pathogens, consistent with the non-distance-dependent mechanism of the Escape Hypothesis. Preliminary data indicate that fungal endophytes potentially pathogenic to plants are present in undigested fruits but are absent from fecal matter, suggesting that gut passage may eliminate certain microbes. Using the Piper sancti-felicis–Carollia perspicillata seed dispersal system in Costa Rica, the study will: (1) assess microbial community differences between fruits and corresponding fecal samples; (2) conduct controlled germination experiments to evaluate seedling fitness and microbiota transmission under different treatments (e.g., seeds from intact fruits, fruits with pulp removed, and seeds from feces); and (3) infer the origin and persistence of microbial taxa by tracking fungal and bacterial communities across fruit, feces, and then seedling tissues. High-throughput sequencing of ITS and 16S markers will be used to characterize microbial communities. Plant health metrics (germination rate, growth, and disease symptoms) will be tracked over a one-year period under greenhouse conditions. This integrative approach, combining microbial ecology, seed dispersal biology, and plant pathology, will yield insights into plant-animal-microbe interactions and the ecological consequences of gut-mediated dispersal for phytobiome assembly and plant performance. 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.