“There has been a tendency to denigrate gossip as sloppy and unreliable” and unworthy of serious study, said David Sloan Wilson, a professor of biology and anthropology at the State University of New York at Binghamton and the author of “Darwin’s Cathedral,” a book on evolution and group behavior. “But gossip appears to be a very sophisticated, multifunctional interaction which is important in policing behaviors in a group and defining group membership.”