Pathway to Resilience

Why are some species of fish able to adapt to pollution levels that are lethal to others? To answer that question, WHOI biologists Mark Hahn and Sibel Karchner are studying the remarkable resilience of Atlantic killifish, common estuarine fish about three inches long. The researchers analyzed four independent, geographically separated populations of killifish that have all evolved resistance to industrial chemicals. The new findings suggest that the species’ genetic diversity gives them the ability to quickly adapt and survive in highly contaminated environments. “It doesn’t seem to be just one gene that is responsible for the resistance,” Hahn says. “It’s a group of genes that are all part of the same pathway.” (Photo by Tom Kleindinst, Woods Hole Oceanographic Institution )