Belding's ground squirrels use five different sources of body odors to create a unique scent for identification. According to research by Jill Mateo at the University of Chicago, the squirrels live a long, crowded life so "it pays to be able to know who's who." From a brief article by John Schwartz in today's New York Times:
Dr. Mateo measured familiarity from the amount of interest squirrels showed in the scents; new smells got more attention than old. She previously showed that squirrels recognize kin, but the new work suggests that they can "tell the difference between Sue and Mary." Each source – glands next to the mouth, back, feet, anus and above the eyes – has a different smell, she said, but each is tied to the individual. "Five different odors say, 'Sue, Sue, Sue, Sue, Sue,' " she said.
