The Organization of Eukaryotic Genes; G. Maroni A Common Ancestry for Drosophila Alcohol Dehydrogenase, and Human 11GBPIiGBPhydroxysteroid, 17GBPIiGBPhydroxysteroid and 15hydroxyprostaglandin Dehyrogenases: Insights into ADH Evolution, Substrate Specificity and Function; M.E. Baker Stress, Resources, Energy Balances and Evolutionary Change; P.A. Parsons Evolution of Drosophila Mating Systems; T.A. Markow Pollination Biology and the Evolution of Mating System in Flowering Plants; K.E. Holsinger Sympatry and Niche Shift among Temperate Zone Chymomyza Diptera: Drosophilidae and the Mate Recognition Controversy; H.T. Band Bauplane, Phylotypic Stages and Constraint: Why There Are So Few Types of Animals; B.K. Hall From Fins to Limbs: Developmental Perspectives on Palaeontological and Morphological Evidence; R. Hinchliffe, E. Vorobyeva Index.