My research program encompasses three interrelated topics: 1) describing the anatomical, taxonomic, and geographic diversity of actiniarian sea anemones, 2) testing hypotheses about the causes and effects of this diversity, and 3) exploring the data and methods used to describe and explain diversity. I have an active field program, and employ both molecular and morphological data to solve evolutionary questions. Sea anemones are a fascinating system in which to study evolution because they are morphologically constrained by their relatively simple organization. Although there is anatomical specialization at the level of cells, tissues, or regions of the diploblastic body, sea anemones are most diverse in terms of life history and biology. Reproductive mode, fertility pattern, symbiotic relationships, and microhabitat use vary among apparently closely related species. Because they manifest both extreme morphological simplicity and great biological complexity, actiniarians provide an opportunity to investigate common evolutionary questions like how changes in development affect morphology or how symbiont acquisition facilitates adaptive radiation, and a means of addressing interesting theoretical problems like constraint and convergence in morphology.