Mentor: Jeffrey Markert, Providence College

Project Location

Providence College

Project Description

This summer’s project will focus on the evolutionary population genetics of the Atlantic killifish.

We are studying how (or whether) these fish can adapt to harmful environmental changes. Our research group combines careful field work with state-of-the-art genetic technologies to understand the evolutionary mechanisms that sometimes allow populations to persist and thrive in heavily polluted habitats.

Although releases of toxins into our waterways have nearly ceased since the 1970s, levels of pollution in local habitats can be quite high. For example, sediments in New Bedford Harbor (NBH) contain levels of polychlorinated biphenyls (PCBs) that are greater than 10,000 times guideline levels. This is an important fact, given that PCBs are linked with a host of health problems in both humans and animals, including neurotoxicity, immunosuppression, developmental problems and carcinogenesis.

Disturbingly, many coastal waterways along the U.S. east coast are similarly polluted, including some in Rhode Island.

While the most contaminated parts of NBH have impoverished biological communities, the plucky Atlantic killifish (Fundulus heteroclitus) is able to thrive in NBH and other highly contaminated habitats. Experimental evidence generated by our collaborators has demonstrated that fish from pristine habitats fare poorly when exposed to the toxins in NBH sediments, consistent with tolerance to PCBs having evolved in situ. Intriguingly, this tolerance has evolved recently on an evolutionary times scale. PCBs were not being released into NBH before the 1940s.

We are currently working with our collaborators at the EPA’s Atlantic Coastal Environmental Sciences division in Narragansett on a long-term project aimed at addressing two distinct questions:

1) What is the population genetic context for the rapid and repeated adaptation to organic pollutants and heavy metals?

2) Which loci and alleles are associated with adaptation to pollution tolerance?

SURF students will gain direct experience working in the field to collect samples for this project, collecting genotype data, and learning the analytical tools needed to interpret these results.