MUSSELS
Hard-Shelled Mollusks
Mussels are a part of the mollusk group, which has more than 130,000
different species. Most mollusks
are under water, but some live on land or in lakes or rivers.
Mussels may form big colonies on shore, grabbing on to rocks in areas by
waves. Some species of mussels even
live in the remains of bones in the really deep water of the ocean!
Most of you know that humans have bones and a skeleton to protect our
body. Unlike humans, mussels have
hard outside shells. A mussel’s
body is soft, and it would be easy food for its enemies without being protected
with a shell. Some mollusks, like
the octopus, don’t have shells. Other
mollusks, like the squid, have a little inside shell.
The mussel’s shell is made up of 2 blue-black, matching valves, with
grooves indicating stages of the mussel’s growth.
A mussel doesn’t have a head! Weird,
huh! Mussels eat by filtering sand
and water through its gills.
Many of you have probably walked along a seashore and most likely found
some shells. One of those shells
might have belonged to a mussel! So make sure you check to make sure there
aren’t any critters in your shell before you take it home (speaking from
experience)!
Mollusks with big shells live in the coral reefs in the Pacific Ocean.
The biggest mussels, or Tridacnas are the biggest mollusks and can get up
to 4 ½ feet long and weigh up to 580 pounds!
That’s huge! Although that
fact is cool, these mollusks could be a danger to divers.
If a diver accidentally puts their hand inside its shell , the Tridacnas closes its valves and catches them! Ouch!
The diver can die from drowning if they can’t get their hand loose.