Home

Over my career I have tackled questions related to how fundamental ecological and evolutionary processes control the structure, function, and diversity of marine ecosystems. With the help of some very talented colleagues and students here at Bowdoin College, I continue to address hypotheses that can explain the stunning diversity found in tropical marine systems, with a record of research that spans all the world’s oceans. My early career at the University of Hawaii (2003 – 2013) was formative in the way I think about the biogeographical and ecological processes that ultimately lead to speciation in tropical marine systems. Working in the Hawaiian Islands and across the Pacific and Indian oceans was an introduction to the incredible scales of connectivity for many marine fishes and invertebrates whose species distributions can span 2/3 of the world’s tropical oceans.

As the late Rick Harrison has pointed out, hybrid zones provide unique windows into the process of speciation. Our recent whole genome sequencing  in a parrotfish hybrid complex in the Tropical Eastern Pacific (TEP) continues to provide insights into how genomic regions introgress between “good” biological species, and very excitingly, provides a genetic footprint of migration out of the TEP and across the Pacific and Indian Oceans. Closer to home in the Gulf of Maine, my lab has been focusing on the recently established hybrid zone between two distinct European green crab populations that meet and mate in the northern Gulf of Maine.  We are particularly interested in how mitochondrial x nuclear interactions are shaping genomic variation across the hybrid zone, and contributing to patterns of warm and cold water adaptation in southern and northern populations We are probing this question at cellular and physiological levels. My former student Jared Lynch has successfully used micro-respirometry to measure OXPHOS performance from isolated mitochondria across a temperature gradient. This summer (2024), Eleanor Hoff (Bowdoin ‘26) and Ashton Dodge (INBRE fellow from Southern Maine Community College) are taking a neurobiology approach to focus on the question of whether patterns of cold water adaptation are ultimately limited by the performance of the central nervous system and its control of cardiac function. To do this, we have been quantifying  cardiac performance in ex vivo heart preparations across a fall-winter temperature ramp  and among the three major mitochondrial haplotypes that characterize the Northeast hybrid zone.

My teaching efforts at Bowdoin have included the  development and co-teaching of the innovative Bowdoin Marine Science Semester, an immersion semester taught at the Schiller Coastal Studies Center, and at field sites in the Gulf of Maine, Bay of Fundy, and the Big Island of Hawaii. Under my leadership, this program was launched in the Fall of 2015, and continues today as the Bowdoin Coastal Studies Semester. We have a strong record of our “BMSS” alumni going on to the best graduate programs in ecology and evolution, medical school, DVM programs, a NOAA Knauss fellow, and non-profits focused on fishery conservation.

Last year, I developed a new course for the Biology Curriculum called Population Genomics, a 2000 level course aimed at students with interests in understanding how genomic variation is shaped by processes such as genetic drift, different forms of natural skeleton, and migration and connectivity among sub-populations. The lecture component is a deep dive into classical theory of population genetics and its application to contemporary genomic data sets while the laboratories often hands on exercises in basic molecular biology “wet bench skills” and “in silico” labs that provide the fundamental programming skills to analyze large genomic data sets.