Eco-evolutionary Dynamics

Conceptually, we are interested in the development of eco-evolutionary dynamics as a framework for understanding natural ecosystems. Traditional ecological theory focuses on how the phenotypes of organisms shape environments. Traditional evolutionary theory focuses on how environments shape phenotypes. Eco-evolutionary dynamics considers these processes as mutually dependent and links them through feedback loops.

Our work focuses on understanding how eco-evolutionary feedbacks work in freshwater and coastal ecosystems. In particular, we focus on interactions between contemporary evolution and population, community, and ecosystem dynamics. Human activity is a key driver of both ecological and evolutionary change. Therefore, we are keenly interested in the impacts of human disturbance on eco-evolutionary dynamics. Some research topics we are currently investigating:

  1. Eco-evolutionary transitions from anadromy to freshwater residency: Transitions from an anadromous to freshwater resident life history are often initiated by human disturbances. Our work suggests that niche construction by freshwater resident populations can differ dramatically from that of their anadromous ancestors. This ecological divergence appears to cause subsequent evolutionary divergence. Therefore, in such cases, ecological and evolutionary divergence can be dynamically linked via eco-evolutionary feedbacks.

  2. Eco-evolutionary dynamics and global change: Climate change, introduced species, and human harvest are contributing to the most rapid rates of trait change ever observed in wild populations. Such trait change has a large potential to impact ecological dynamics. We are examining the eco-evolutionary consequences of human disturbance in model systems and natural ecosystems.

Anadromous Fish Conservation

Because of their complex migratory life histories, anadromous fishes are particularly vulnerable to human disturbances. The loss of anadromous fishes causes major changes to the ecology of coastal freshwater and marine ecosystems. Developing effective conservation strategies requires detailed information on the ecology and evolution of anadromous species. Some ongoing projects related to the conservation of anadromous fishes:

  1. Stock structure and bycatch: We are investigating range-wide population genetic structure in alewife and blueback herring along the Atlantic Coast of North America. Populations of these species are in steep decline. We are deploying a suite of molecular markers to determine appropriate management units and to identify the geographic origins of river herring caught as bycatch in marine fisheries.

  2. Evaluating and managing hatchery stocking practices: Stocking can be an effective way to rebuild depleted runs but must be managed appropriately to avoid the deleterious effects of inbreeding, outbreeding, and artificial selection. We are currently working with fisheries managers to develop stocking practices to maximize the efficacy of stocking and minimize potentially deleterious effects.