When many of us think of "nature" we probably think of forests, lakes, or meadows. We know that we see nature in our gardens or in our neighborhood parks. Chances are good that when we're walking down the streets of Manhattan, or Chicago, or downtown Detroit, we're not giving much thought to the nature around us.
Dr. Robert Dunn and a team of researchers have recently published an article in the journal PlosONE, in which the team undertook the task of studying nature in one of the most urban environments in the world: Manhattan.
But they didn't go to the parks of Manhattan. No, they studied the most common urban greenspace available: street medians.
Diversity in Unlikely Places
What they found in their study was that no fewer than 13 different species of ants live in the street medians of Manhattan. They found that both native and introduced species of ants lived side by side, and that the types of ants that were found in a median was directly influenced by factors such as whether there was a shade tree there, or a garbage can, and what the pavement to median ratio was -- pavement ants (those ants we have all seen that build their hills in the cracks of sidewalks) chose those medians that tended to be small and surrounded by plenty of concrete. Others, such as thief ants and cornfield ants, were more likely to live where there was plant matter such as trees or groundcover. They hypothesize that without all of these ant species in our urban areas, the amount of litter and other waste would be much higher than it is. We have ants partially to thank for keeping our city streets clean.
While the study focused on ants, Dr. Dunn and his team want to encourage people in urban areas to observe more of the nature around them. He says that we know more about the animals and insects in the rain forests than we do about those in our urban areas. He gives the example of a recent West Nile Virus outbreak in Chicago, in which residents kept finding dead crows who had been infected with the disease. He said there was no way to determine what percentage of crows had been infected, because no one had ever bothered collecting data about how many of them lived in the city in the first place.
Dr. Dunn appeared on the podcast Curiouser and Curiouser to discuss his findings as well as how he obtained the data (an amusing story in and of itself). He makes a good case for appreciating the wildlife around us, even if it is nothing more than common ants and crows.