Dr. Munshi-South has joined the ranks of a small but growing number of field biologists who study urban evolution — not the rise and fall of skyscrapers and neighborhoods, but the biological changes that cities bring to the wildlife that inhabits them. For these scientists, the New York metropolitan region is one great laboratory.
White-footed mice, stranded on isolated urban islands, are evolving to adapt to urban stress. Fish in the Hudson have evolved to cope with poisons in the water. Native ants find refuge in the median strips on Broadway. And more familiar urban organisms, likebedbugs, rats and bacteria, also mutate and change in response to the pressures of the metropolis. In short, the process of evolution is responding to New York and other cities the way it has responded to countless environmental changes over the past few billion years. Life adapts.