TUBE WORM Morgan Patton 2/13/14 Marine Biology Honors

CHARACTERISTICS  This colorful tube worm inhabits the seas around the Greek Isles.  These are marine invertebrates and are found in the intertidal zones.  Tube worms can reach a length of 2.4 m (7 ft 10 in) and their tubular bodies have a diameter of 4 cm (1.6 in).  They do not depend on sunlight for their source of energy.  They feed on tiny bacteria that get their energy directly from the chemicals in the water through a process known as chemosynthesis.

TAXONOMY  Kingdom: Animalia  Phylum: Annelida  Class: Polychaeta  Order: Canalipalpata  Family: Siboglinidae  Genus: Riftia  Species: R. pachyptila

BODY STRUCTURE  The tube worm does not have many predators; there are not many creatures that live on the sea bottom at such depths. They have a highly vascularized, red "plume" at the tip of them which is an organ for exchanging compounds with the environment, and if they feel threatened, the plume may be retracted into the worm's protective tube.  They have no digestive tract, but the bacteria turns oxygen, hydrogen sulfide, carbon dioxide, etc. into organic molecules on which their host worms feed.  The bright red color of the plume structures results from several extraordinarily complex hemoglobins found in them, which contain up to 144 globin chains.

ENERGY AND NUTRIENT SOURCE  With sunlight not available as a form of energy, the tubeworms rely on bacteria in their habitat.  Tube worms are partially dependent on sunlight as an energy source, since they use free oxygen.  Tubeworms are unique in being able to use bacteria to indirectly obtain all materials they need for growth from molecules dissolved in water.

REPRODUCTION  When reproducing females release lipid-rich eggs into the surrounding water, the eggs begin to float upward.  The males then unleash sperm bundles that swim to meet the eggs.  After the eggs have hatched, the larvae swim down to attach themselves to the rock.

GROWTH RATE AND AGE  Tube worms have the fastest growth rate of any known marine invertebrate.  These organisms can colonize a new site, grow to sexual maturity, and increase in length to 4.9 feet (1.5 m) in less than two years.

BIBLIOGRAPHY   worm worm