This award supports a new, multidisciplinary research training program focused on understanding nonlinear processes in biological systems at the level of cells to that of populations and communities. A group of 25 faculty from eight departments at the University of California at Davis will train undergraduate, graduate and postdoctoral students with backgrounds in mathematics or biology in non- linear mathematical methods suited to the analysis of a variety of biological problems. Graduate students will be required to complete a set of core courses in mathematics, and additional training in laboratory or fieldwork-based biology, depending on individual backgrounds. Laboratory rotations will be required as will participation in a year- long group research project involving trainees at all levels. Graduate students will then complete a multidisciplinary thesis research project under the guidance of two mentors in one of three general research areas: Cellular, Biofluid or Population Dynamics. In its overall approach, the program will emphasize collaborative research and mentoring by faculty and by graduate and postdoctoral students within and across training levels.