Modeling the Impact of the African Elephant, Loxodonta africana, on Woody Vegetation in Semi-Arid Savannas by Peter William Joseph Baxter B.A. (University of Dublin, Trinity College) 1996 A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Environmental Science, Policy and Management in the GRADUATE DIVISION of the UNIVERSITY OF CALIFORNIA, BERKELEY Committee in charge: Professor Wayne M. Getz, Chair Professor Dale R. McCullough Professor Cheryl J. Briggs Summer 2003