Unexpected biodiversity springs from the depths
Five-hundred and eighty-five new species of crustacean have been found in the depths of the Southern Ocean, thanks to three sampling expeditions set up as part of the ANDEEP (Antarctic benthic deep-sea biodiversity) project. Unexpected levels of biodiversity were found in this dark and largely unstudied place, challenging assumptions that deep sea diversity is depressed in this area.
On their expeditions, Angelika Brandt and colleagues collected biological specimens and environmental data from different regions 774 to 6,348 metres under the surface of the Weddell Sea and adjacent areas. The Weddell Sea is an important source of deep water for the rest of the ocean and provides a possible route for species to enter the deep water. In line with this, the team found deep-sea faunas that were also found in adjacent shelf communities and in other oceans.
They spotted 674 species of isopod — a diverse order of crustaceans — of which over 80% were new to science. In some regions, groups of slope-dwelling isopods and marine worms included species that had invaded from the Southern Ocean’s deep continental shelf. Species living in the deepest parts of the Weddell Sea tended to have strong links to other oceans, particularly if they were good dispersers, like certain amoeboids. But poor dispersers, such as isopods, nematode worms and seed shrimps, were Southern Ocean-specific species.
CONTACT
Angelika Brandt (University of Hamburg, Germany)
Tel: +49 40 42838 2278; E-mail: abrandt@zoologie.uni-hamburg.de