For many sessile marine invertebrates, the larval stage is the most important mode of dispersal, and larval recruitment can directly affect the growth, survival and structure of populations. However, the nature and dynamics of larval dispersal, and thus gene flow, have been difficult to characterize. The recent development of new and rapidly applied molecular techniques may make it possible to assess dispersal by examining the genetic "relatedness" of populations. The PI proposes to learn and adapt molecular genetic techniques for the study of coral population genetics. The phylogenetic diversity and population structure, over large and small geographic scales, of the widely distributed brooding coral Acropora palifera will determined. Phylogeographic genotypes, along the length of the Great Barrier Reef, will be characterized by contrasting restriction endonuclease patterns of small and large subunit ribosomal DNAs in this coral with closely and distantly related corals. The relatedness of colonies from reefs in the same geographic area will also be evaluated to assess the nature of local gene flow by restriction fragment length polymorphism analysis of mitochondrial DNA and DNA fingerprinting.
