This submission consists of published papers presenting original research carried out by the writer since 1967. The research has covered aspects of the taxonomy, biogeography, biology, ecology, pheromone chemistry and control of tropical fruit flies (subfamily Dacinae). Papers published on research used for the previously awarded degree, Doctor of Philosophy, are not Included. The primary aim of the research has been to Increase our knowledge of the species of Daclnae, particularly In the South PacHlc area, and to elucidate new information on their geographic distributions, host plants (wild and commerclal), biology, ecology and pheromone communication systems. In the taxonomy studies a new subgenera and 172 new species have been described. The first descriptions of dacine species from the South Pacific area were by Macquart (1835) and Francis Walker (1859-1865). The 172 species described by the writer represent 60% of the 290 species now known. This research has culminated in a comprehensive monograph (publication No.38) treating all 290 species. It Included, for the first time, a revision of the Australian fauna and data on biology, distribution and attractant records. A new generic/subgeneric classification has been developed based on data of biological and zoogeographic significance in addition to standard morphology. This is the first supraspecific classification of Dacinae that accommodates species from all blogeographlc regions of the world. Many species, including some major pest species, occur within sibling species complexes, e.g. Bactrocera tryoni (Froggatt) (Queensland fruit fly) and Bactrocera dorsalis (Hendel) (Oriental fruit fly). In the diagnosis of sibling species, a combination of techniques has been used, viz., morphology (including scanning electron microscopy), cytology, enzyme electrophoresis, pheromone chemistry, biology (host records, assortatlve mating experiments and sterility studies) (see publications 18 and 29). Currently, the writer is using a combination of these techniques in a study of the Oriental fruit fly complex of South East Asia. Consequently, the taxonomic research has gone beyond standard morphological taxonomy and has incorporated other disciplines. This is the first time that such a broad approach has been taken in tephritld taxonomy. Results of the taxonomic research have had significant economic applications – (1) Species of major economic Importance throughout the Pacific area have been determined. (2) Data have been incorporated Into Plant Quarantine guidelines for Asian and South Pacific nations. (3) Target species and their host fruits have been defined for development of post­ harvest dlslnfestatlon treatments. This has been of particular value to 'developing' countries which have been building international trade in fresh fruits. A new family of Strepsiptera containing one species has been described (publication No.26). The species, Dipterophagus dacl Drew and Allwood, is the first strepsipteran parasite to be described In Dlptera and now has been recorded from eleven dacine host species across Northern Australia. The ecological research has focused on species distribution and abundance with particular emphasis on populations in the endemic rainforest habitat (publications 12, 15, 19, 21, 24, 25). Host records have been obtained for species breeding in Queensland rainforests and are published in publication No.38. Prior to this research, very little had been done on tropical fruit flies in their endemic habitat, even though fruit fly ecology has received a great deal of attention worldwide over many years. An Important new finding in the rainforest ecology is that the major biotic population­ reducing mechanisms In that habitat are fruit feeding vertebrates (publications 32 and 36), not hymenopterous parasites as previously thought. The biological research has been concentrated on aspects of the identity, distribution and abundance of adult fly food In nature, for certain dacine species. These investigations have led to the discovery that certain bacteria species are utilised as adult food and have established a much improved understanding of fruit fly biology. A discovery of particular importance Is the Introduction and distribution of bacteria over the host plant by regurgitation. Relevant publications are Nos 22, 30, 33, 34, 43 and 45. These studies have increased our understanding of fruit fly/host plant relationships which Is now proving vital to our knowledge of fruit fly biology and development of control methods based on attractants. The fruit fly/bacteria biology data are now being used by organisations developing bait spraying strategies for fruit fly eradication programs; for example, the Western Australian Department of Agriculture eradication program for Bactrocera tryoni (Queensland fruit fly) and the New Zealand Department of Agriculture contingency plans for eradication of Introduced species. Understanding the biology of fruit flies has become an important facet of the taxonomic research. Biological data have been used to help identify sibling species. Also, this work has shown that understanding the associations of fruit fly species and their host plants, the biological differences between even closely related species, and the factors governing species distribution, are vital to understanding speciation and therefore to sound taxonomy. Control studies have centred on the use of food bacteria species in attractant bait sprays. Improved attractancy has been obtained by the addition of bacteria to hydrolysed protein suspensions (publication No.37). Chemical analyses of volatile bacterial metabolites have Identified some components, and their attractant properties are being assessed. A major contribution of the research has been on emphasising the value of basic research in finding solutions to economic problems. Such solutions could not be found in short-term applied research. Significant discoveries arose from studies of the fruit flies in their endemic habitat and not by pursuing the standard economic entomology approach In commercial orchards. The work has also shown that taxonomy and biology are Interdependent and that neither should be overlooked in biological research programs.