HR: 08:30h
AN: NB51B-01    [Abstracts]
TI: Biological and Earth History as Revealed by Australian Subtropical Sand Islands
AU: * Page, T J
EM: t.page@griffith.edu.au
AF: CRC for Freshwater Ecology, Centre for Riverine Landscapes, Faculty of Environmental Sciences, Griffith University,, Nathan, QLD 4111 Australia
AU: Hughes, J M
EM: jane.hughes@griffith.edu.au
AF: CRC for Freshwater Ecology, Centre for Riverine Landscapes, Faculty of Environmental Sciences, Griffith University,, Nathan, QLD 4111 Australia
AB: Off the coast of subtropical Queensland in Australia lie a series of large, forested sand islands. These islands have attracted the interest of geologists, hydrologists and biologists because of the sequential formation of ancient and recent dunes and the presence of abundant and varied freshwater ecosystems. These range from small coastal creeks, water-table "window" lakes and isolated "perched" lakes set well above the groundwater. These islands have only been separated from the mainland for a relatively short 6000 years or so and thus theoretically should display little differentiation from mainland populations. We sequenced two mitochondrial genes from the nearly omnipresent macroinvertebrate crustacean, Caridina indistincta, to investigate the nested island-within-island nature of freshwater-restricted taxa on these islands. This makes for potentially interesting biogeographic patterns between water bodies on islands, between islands and between the islands and the mainland. When phylogeographic patterns are related to geomorphological ones, inferences can be made about the methods, timing and direction of faunal colonisation and geologically induced vicariance. We discovered a series of lineages, ranging from cryptic species whose divergence considerably predates the islands themselves, to shallow differences within and between islands and the mainland. This highlights the complex biological and geological history of the area.
DE: 9901 NABS Student Award - Basic Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly