A new study from North Carolina State University shows that insects and other arthropods play a significant role in disposing of garbage on the streets of Manhattan –from a December 2, 2014 news release.  Insects were shown to consume food waste (junk food) left in the median of New York City streets.  The study also confirmed that ants and rats are competing for the same food source in these areas.  So, what is not consumed by the insects is food for rats and could be a limiting factor for a rat population if the insect population was sufficient.  Ants are cleaning up the environment and possibly limiting other pests.