Mollusca

From land-dwelling snails to creatures of the deep sea, molluscs are incredibly diverse, yet share at least one common characteristic: their shells. Let’s take a look at how their shells differ:

All molluscs have shells, whether they are visible or not:

Their shells are produced by the mantle, and typically sit on top to protect their soft bodies from predators and other harm. In animals such as octopuses and squid, which don’t appear to have shells, they actually have a “shell” on the inside: when dissecting a squid, you can often find the “squid pen” located just above the collar.

Polyplacophora:

  • Name meaning: “Many plate bearing”
  • Example: chitons

Gastropoda:

  • Name meaning: “Stomach, foot”
  • Example: snails

Bivalvia:

  • Name meaning: “Two valves” (two shells)
  • Example: clams

Scaphopoda:

  • Name meaning: “Shovel foot”
  • Example: tooth/tusk shelled animal
  • Shells were once used as currency by First Nations peoples

Cephalopoda:

  • Name meaning: “Brain, foot”
  • Example: octopuses