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Research Objectives:
Notothenioids are a major group of fish in the Southern Ocean. The ancestral notothenioid fish stock of Antarctica probably arose as a sluggish, bottom-dwelling perciform species that evolved some 40 to 60 million years ago in the then temperate shelf waters of the antarctic continent. The grounding of the ice sheet on the continental shelf and changing trophic conditions may have eliminated taxonomically diverse late Eocene fauna and initiated the original diversification of notothenioids. On the high antarctic shelf today, notothenioids dominate the ichthyofauna in terms of species diversity, abundance, and biomass, the latter two at levels of 90 percent to 95 percent. Since the International Geophysical Year of 1957–1958, fish biologists from the Antarctic Treaty nations have made impressive progress in understanding the notothenioid ichthyofauna of the cold antarctic marine ecosystem. However, integration of this work into the broader marine context has been limited, largely because of lack of access to, and analysis of, specimens of subantarctic notothenioid fish.
The fish of this suborder are critical for a complete understanding of the evolution, population dynamics, ecophysiology, and ecobiochemistry of their antarctic relatives. Our project will support an international, collaborative research cruise to collect and study fish indigenous to subantarctic habitats. Research topics include systematics and evolutionary studies; life history strategies and population dynamics; physiological, biochemical, and molecular biological investigations of major organ and tissue systems; genomic resources for the subantarctic notothenioids; and ecological studies of transitional benthic invertebrates.
In a world that is experiencing changes in global climate, the loss of biological diversity, and the depletion of marine fisheries, the antarctic and subantarctic regions and their biota offer compelling natural laboratories for understanding the evolutionary impact of these processes. Our work will contribute to developing a baseline understanding of these sensitive ecosystems, one against which future changes in species distribution and survival can be evaluated judiciously.
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