Clam Muscle

rivers and streams, some groups live on the seafloor.
Clams have a muscular foot and use it to make a burrow in the sediment. Clams are filter feeders, and have siphons to pump water over their gills. That removes both plankton and oxygen food from the water.
Freshwater habitats,
There are competitive interactions for the clam. Competitive for space, whether sand, mud, rocks, or wood. Competition for food as well.
Since clams are filter feeders, they eat small organisms and algae that they pull out of the water.
Clams go through several stages before they look and act like a clam. The smaller males release a sperm into the ocean to meet up with the eggs produced by the lager clams that have becomes females.