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Welcome to the Pespeni LabĀ at the University of Vermont (UVM)!

The goal of our research program is to understand the mechanisms that have allowed populations to adapt to local conditions and that may confer resilience to future changes in conditions. Specifically, we look at the roles of several factors in shaping adaptive capacity: (1) population genetic factors such as genetic diversity, gene flow and population size, (2) environmental heterogeneity in space and across evolutionary and ecological time scales, (3) parental environment and epigenetic factors, and (4) the microbiome. We use a diversity of approaches in both field- and lab-based studies including experimental genomics, selection experiments with offspring from wild-caught animals, physiology, morphometrics, and developmental genetics. We currently study a range of organisms that are each best suited to address specific questions to understand the mechanisms of adaptive evolution.

Some of the projects we have going on in the lab right now are:

(A) What is the role of the microbiome in shaping the tipping point for sea star pathogenesis in Sea Star Wasting? What is the interaction between host (sea star) genotype and the microbiome in organisms that are susceptible versus resistant? Are there adaptive alleles present in surviving sea stars in the wild? We are addressing these questions in three sea star species that differ in susceptibility and with a combination of experimental time-course infections in the lab and field sampling.

(B) What are the roles of population genetic diversity and epigenetic factors in shaping sea urchin resilience to ocean acidification and disease? Can we confirm the putative adaptive roles of genetic variants through functional studies using CRISPR/Cas9 genome editing techniques? We are using a range of sea urchin species, long-term acclimation studies, field collections, and transgenerational and single-generation selection experiments to address these questions.

(C) What are the costs of adaptation to one environmental stressor when organisms exist in a world of multiple concurrent or sequential stressors? How does loss of genetic diversity that occurs with rapid evolution effect resilience and how does this effect depend on the genomic architecture of the trait(s) under selection? We are using multi-generation selection experiments in copepods to address these questions.

(D) We also have collaborative projects with Tyler Evans at CSU East Bay on selection and resilience in bay oysters and Eric Sanford at UC Davis on the eco-evolutionary dynamics of adaptive variation in prey drilling capacity in Nucella dog whelks.