Evolutionary study of Drosphilid flies

Drosophilid flies of various species are known to inhabit the flowers of different plant species in Hawaii, South America and Australia, feeding on microorganisms, courting and mating, with females inserting their eggs into the flower petals. The two Australian species recorded here have particular advantages for research in evolutionary genetics – their host plants occur in isolated populations spread over very broad geographical areas (that is, climatic and topographical variation). Thus genetic variation among populations in various traits such as physical (e.g. wing size as a proxy for body size) and physiological (e.g. ovariole number as a proxy for reproductive capacity) can be measured and related to climatic and/or physical features of each location. The Scaptodrosophila/Hibiscus system can be considered a model system for research in evolutionary genetics. The basic question for this type of research – How much genetic variation is there within and between populations, and what causes any such variation?