Mussels and Clams

Characteristics :

  • Have a soft body that is protected by a hard shell having two hinged halves or valves
  • Have a hard shell made of calcium carbonate
  • Body covered by thin, fleshy tissues called a mantle; the mantle secretes the shell as the animal grows
  • Growth lines on shell relate to age; each growing season is marked by the space between two growth lines; there may be several growing seasons within a year's time
  • Move about using a muscular, hatchet-shaped foot
  • Mantle forms two tube-like siphons for carrying water in and out of body
  • Breathe oxygen dissolved in water with gills
  • Eat by filtering food from teh water that flows over their gills
  • Have an open circulatory system, meaning that the circulating fluid is not always contained within tubes
  • Have a nervous system that includes simple sense organs
  • Life cycle may include a free-swimming or a parasitic larval stage and a more sedentary adult stage
Taxanomy:
  • Kingdom: Animalia
    • Phylum: Mollusca
      • Class: Bivalvia
        • Order: Arcoida (ark shell), Limoida, Myoida (angel wing, shipworm, soft-shell clam, others), Mytiloida (fan shell, mussel, pen shell), Nuculoida (nut clam), Osteroida (scallop, oyster), Pholadomyoida (deep ocean mulluscs), Pteriodia (file shiell, jingle shell, oyster, scallop), Solemyoida (awning clam), Trigoniodia, Unionoida (freshwater mussels), Veneroida (cockle, jewel clam, razor clam, venus clam, others)
Student Challenge:
 
  • Research the historical uses of freshwater mussels in North America and identify which were used in Kentucky. Use your findings to develop a display shoing the importance of freshwater mussels to Kentuckians. Include a timeline in your display. 
  • Using resources such as the State of Kentucky's Environment report, Kentucky Division of Water, U.S. Geological Survey, Kentucky Geological Survey, and the World Wide Web, determine how water quality affects populations of mussels and clams in Kentucky's streams and rivers. Create visual representations, such as charts or graphs, of the data you find.
  • Using the scientific method as a model, design a method of determining how water temperature affects growth and reproductive ability of freshwater mussels. 
  • Freshwater mussels are among the most endangered organisms in North America. Predict the effect on aquatic ecosystems in Kentucky if all freshwater mussels became extinct. Write a short story that illustrates your prediction.