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Abstract UNDERWORLD EVOLUTION: DIVING DISCOVERIES OF RELICT CRUSTACEANS IN MARINE CAVES Thomas Iliffe1 and L. Kornicker2
Anchialine (marine groundwater) caves of the Bahamas are inhabited
by a diverse but relatively unstudied fauna, offering considerable
opportunity for discovery of many new and ecologically significant
organisms from potentially endangered environments. Anchialine caves
can be classified as extreme habitats due to their total lack of
light, limited food supply, low dissolved oxygen and unique biogeochemical
characteristics. The isolated nature of anchialine caves provides
long-term climatic and environmental stability unprecedented in
other habitats, with the possible exception of the deep sea. As
such, many cave organisms are primitive "living fossil"
species that could provide insight into the origins, evolution and
dispersal of marine life. In collaboration with Dr. Louis Kornicker
of the Smithsonian's Invertebrate Zoology Department, a series of
diving-based expeditions are exploring and investigate the biodiversity
of anchialine caves within the Bahama Islands. Our previous studies
in the Bahamas have led to the discovery of more than 80 new taxa
of marine cave-adapted crustaceans and fish. A number of these can
be considered relict, living fossils with closed related species
inhabiting caves on opposite sides of the Atlantic and Pacific Oceans.
This highly anomalous distribution suggests an origin in caves early
in the Earth's history when the continents were combined in a single
land mass. Other cave species from the Bahamas have close relatives
in the deep sea suggesting close affinities between the two ecosystems.
Since many cave animals are found only in a single cave, pollution
or destruction of these habitats with result in extinction.
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