Dr. Dunigan is fascinated by the evolving concept of “virus” in the context of the Five Great Questions, and his research explores the many ways viruses interact with organisms, from the consequences of infection to virology. For the past several years he has studied the chloroviruses, which are evolutionarily related to other large DNA viruses, collectively known as “giant viruses”. He is investigating many aspects of chloroviruses including the virion structure and function; genome structure, function and evolution; metabolic changes associated with infections, as well as the role of algal viruses in aquatic ecosystems. Surprisingly, chloroviruses are associated with certain neurological disorders and his role includes evaluating their natural history to understand the likelihood of humans coming into contact with chloroviruses. In addition to defining the hosts in aquatic systems, he is evaluating a key issue to this linkage, can chloroviruses replicate in mammalian cells and/or tissues and what are the neurological consequences of these infections? Equally important are the explorations of the roles of chloroviruses in ecosystem functioning that has led to the discovery of virotaxis, ecological catalysis and that virus is food.