Complex nervous systems rely on multiple cell types with unique functions. The evolution of this cellular complexity is not well understood. We are interested in neurogenesis in the cephalopod, an animal with an complex nervous system that is independently evolved from vertebrates and Drosophila, traditional models. We use the retina and optic lobe to study nervous system development and evolution with goal of better understanding fundamental principles involved in generating neural complexity. In particular we are interested in the role of Notch signaling in neuralepithelial tissues like the cephalopod retina and its function to maintain a progenitor pool as waves of specific cell-types differentiate sequentially.