Tuesday, November 3, 2009


Dr. Steve Haddock of MBARI (www.mbari.org/staff/haddock) has joined the Marine Invertebrate Biocode Team to explore the gelatinous zooplankton, or 'gelata' of the pelagic, open water habitat that surrounds Moorea. After bringing the scientific divers up-to-speed on the specialized equipment and methods used to dive safely and productively in this 'extreme' habitat, Steve has immersed us in a completely blue world with a seemingly alien fauna. At a second glance however, most of these animals have relatives or connections much more familiar to us.

Pteropods for example, are highly modified gastropods, or snails- some of which have given up their shells in trade for a 'flying' lifestyle, with two beating fins or wings. Salps are the open ocean forms of ascidians ("sea squirts") that use the powerful water pumping system evolved originally for filter feeding, for 'jet propulsion' in the open waters.

The system truly belongs to the jellies- both the Medusae ("jellyfish") and the Ctenophores ("comb jellies"). In the deep water, without obstacles to bump into, the jellies have taken on a diversity of form unrivaled in the blue. Some are 'traditional' and have a rounded body with hanging tentacles. Others are not so conservative, and resemble nothing so much as actively moving lotus blossoms, fanning open 'petals' as they drop and recoil tentacles in an effort to catch even smaller members of this world.


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