Nicholas J. Strausfeld, PhD, Director, Center for Insect Science and Regents’ Professor of Neuroscience Emerging evidence suggests that distantly related animals such as mice and flies manifest similar behaviors because they have genealogically corresponding brain centers. The view is that a common ancestor had already evolved circuits for behavioral actions, memory of such actions, and their consequences more than half billion years ago. Evidence that those circuits have been inherited through geological time challenges how we as a species relate to animals that we view as wholly different from ourselves.