Research Interests
Seed dispersal is an important ecological process that, at the large scale, can influence the spatial structure of plant populations, and at the smaller scale, can increase individual plant fitness. As seeds and recruiting seedlings must contend with heterogeneous environmental conditions, kin competition, and pest pressure, dispersal may offer a mechanism to reach suitable germination sites such as light gaps, or escape ecological stressors. As a genetic process, seed dispersal may move genetic variants across the landscape, with the potential to affect the fine scale genetic structure of neutral and potentially functional variation.
I am especially interested in seed dispersal as a mechanism to escape mortality by natural enemies. This idea was originally put forth by the Janzen-Connell hypothesis which predicts that seed and seedling mortality should be disproportionately high near conspecific adult trees where host-specialized pests respond to high progeny density. In humid tropical forests, soil-borne pathogens may be a particularly salient challenge, especially for small-seeded species. Because pathogens interact directly with host genotype and may differentiate at small spatial scales, dispersal away from local sites may offer both an ecological and genetic advantage. Focusing on a tropical understory tree in Ecuador, I am combining ecological transplant experiments in the field with high-throughput genomic tools in the lab to investigate the ecological, genetic, and functional roles of seed dispersal.
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| My focal species is Pentagonia macrophylla, an animal-dispersed understory tree in the Rubiaceae family. | Pentagonia macrophylla seeds germinating in petri dishes. |
Seedlings in 1-m2 plots were tracked for mortality and infection status over time. |
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Naturally germinating seedlings with putative symptoms of pathogen infection. |
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