There are 35 major animal body types that have existed for over a half billion years, yet there are millions of species that exhibit an endless range of morphological diversity. An understanding of the evolution of animal form must take into account the developmental processes responsible for creating biological patterns, and how these processes are shaped by evolution. Data obtained from model systems have defined our current understanding of how patterns are generated and in doing so have allowed us to generate testable hypotheses in other systems. Such inquiries have uncovered a remarkable number of shared developmental pathways at both the cellular and molecular levels across phyla, suggesting that some pathways are more prone to change than others. This advanced seminar will focus on molecular mechanisms of metazoan development and evolution, using primary literature to develop critical skills. Format: discussion, three hours a week. Evaluation will be based on class participation and short papers. Prerequisites: Biology 202. Enrollment limit: 2 sections of 12 each (expected: 2 sections of 8 each). Open to juniors and seniors, with preference given to senior Biology majors who have not taken a 400-level course.