Research

As a population geneticist, I am interested in how genes change from one generation to the next and among contemporary populations. I have carried out research investigating each of the five evolutionary forces: selection, mutation, genetic drift, gene flow, and non-random mating. I am also interested in ecology as the arena in which evolution takes place. I work on plants because of their beauty and inherent interest as well as their many desirable attributes as study organisms. Most of my projects combine molecular genetic analysis with various kinds of phenotypic data.

Ongoing projects:
With Juvenal Lopez ’16, I am examining the population genetic structure of a wild population of pin oak (Quercus palustris) that has spread in Colby woodlands from ornamental plantings. We are interested in the role of hybrid vigor in facilitating range expansions as manifested by invasive introduced species.

I have an ongoing collaboration with Nat Wheelwright of Bowdoin College to explore the population genetic consequences of colonization of islands in the Bay of Fundy by the blue flag iris.

I am investigating the role of colonization and gene flow on the mating system for populations of a tropical shrub, Witheringia solanacea, on the Pacific Slope of Costa Rica. In addition, I will be comparing contemporary gene flow by bird-dispersed seeds to historical gene flow as inferred by genetic markers.

In my most recent completed project, with the help of dozens of Colby students and two Costa Rican technicians, I demonstrated that the evolution of self-fertilization in small populations was promoted more by siring success than by enhanced capacity to set fruit when pollinators were scarce.

Please see the papers listed on my CV for titles of completed projects.