An international recognized expert on the spread of infectiousdiseases, University of Oxford zoology professor Roy M. Anderson will give three free public lectures at UC Davis this month. The first talk, "Populations, Infectious Diseases and Immunity: A Very Non-Linear World," is Monday, April 18. The second lecture addresses "The Ecology of Viral Infections in Human Communities and the Evolution of Virulence," Wednesday, April 20. In the third talk, Anderson will discuss "The Pandemic of Aids: The Transmission Dynamics and Evolution of HIV," Thursday, April 21. All the talks begin at 4:10 p.m. in Medical Sciences Building C. The lectures are sponsored by the Tracy and Ruth Storer Lectureship in the Life Sciences, an endowment established to bring eminent biologists from other institutions to UC Davis.