GENOMIC DNA RESTRICTION FRAGMENT LENGTH POLYMORPHISMS AT A HIGHLY POLYMORPHIC LOCUS DISTINGUISH OLD AND NEW WORLD SUBSPECIES OF THE HONEY BEE, Apis mellifera L. By MARGARET ANNE MCMICHAEL A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 1994