Dr. Arthur N. Popper is a professor emeritus and research professor in the Department of Biology at the University of Maryland.  Popper has been studying hearing, evolution of hearing, and effects of noise on hearing, for over 40 years.  He has published several hundred scientific papers as well as over 50 books on hearing, and related topics. In his lecture, Popper will discuss his research on hearing, as well as provide a general understanding into why and how hearing changes as we get older or are exposed to loud sounds in the environment.