Brian Wynne, a British expert on environmental risk assessment who was to present a lecture tonight on public policy and the potential risks related to agricultural biotechnology, has canceled his talk due to travel difficulties. His public talk, "Ambiguous Science and the Precautionary Principle Controversy in Agriculture: Towards Reflexive Risk Assessment?" was to be the third of eight events in the "Biotechnology, Policy, and Society Lecture Series," held on selected Thursday evenings until early March. The next lecture is scheduled for Nov. 30, featuring speakers Peter Kareiva of the National Oceanic and Atmospheric Administration and Arthur Reingold of the UC Berkeley Division of Public Health Biology and Epidemiology. The series is coordinated by the UC Davis Center for History, Society, and Culture.