Evolution Ecology of Cities

     An urban city does not seem like it would be the best place for most animals. Through research, scientists have discovered that cities actually drive species to evolve on a rapid scale to accommodate for pollution, traffic, and shrinking habitats.

     Evolution on a genetic level is when genes change in response to their environment. Issac Wirgin of New York University has theorized that urban environments speed up the process of evolution, a process that most scientists believe to be very slow. Wirgin also adds that this can be both a good and bad thing. Another take on the definition of evolution is "survival of the fittest". Many species can last the cities, but not the other animals adapting to their environment that impact their own lives.

     An example of urban evolution in action would be cliff swallows in Lincoln, Nebraska. Over the course of 30 years, scientists saw a steady decrease in the death toll of swallows around a specific underpass. The traffic patterns had not changed and the location of these cliff swallows hadn't either, their genes evolved to adapt to their environment in relatively short time. Birds that ended up being killed by vehicle collisions had significantly longer wings than live birds that were caught in nets for research. According to Charles Brown, an ecologist at the University of Tulsa, says this is no coincidence. The short-winged birds are able to dodge traffic much easier than the long-winged birds. Comparing these findings with the data trend of the number of decreasing bird deaths over the last 30 years these researchers can credit the numbers to evolution.

     While cities are still not the most ideal environments for most animals to call home, evolution is helping to make their chances or survival much faster than most scientists had originally thought.

-Wainam