Sandy Shores Trivia Quiz

Answer:

All of the animals you saw in this quiz are invertebrates, which means that they do not have a vertebral column (unlike mammals, such as humans!) Invertebrate animals can be further subdivided into phyla, which is what we have done here. The animals listed in this quiz belong to either the Mollusca or Arthropoda phyla.

Phylum Mollusca encompasses thousands of species (collectively known as mollusks) that are mostly, but not exclusively, marine creatures. Some live in freshwater or deep water, and many can be found on beaches. Many mollusks have soft bodies, mostly composed of muscle, that are protected by harder outer shells. Mollusks use their shells to protect themselves from predators or other dangers. They typically reproduce by laying eggs. Mollusks can be further divided into classes, which include gastropods, bivalves, cephalopods, and polyplacophorans.

Gastropods are one of the most common mollusks that one may encounter in a walk by a sandy shore, because they commonly leave behind seashells. This class includes snails and slugs, some of which are eaten by humans! (think escargot, the French snail dish loved by some and hated by others). Many species of abalone and conch also belong to this group.

Bivalves, named after the two valves or shells that they have, are a large group that includes many species of clams, scallops, oysters, geoducks, piddocks, and mussels. As a result, bivalves are some of the mollusks that humans most frequently consume as food. Many a seafood restaurant will serve some, if not all, of these bivalves!

Cephalopods are a class of mollusk that do not quite look like other animals in their phylum. While they are also invertebrates, they tend not to have a protective shell. Animals in this class include the squid, the octopus, and the cuttlefish. Unsurprisingly, they are also a relatively popular type of seafood to eat.

Polyplacophorans are almost all chitons, a species of mollusk that is also referred to as sea cradles. Chitons have oddly shaped protective shells that can be colorful, and therefore are attractive to seashell collectors. People in Caribbean islands like the Bahamas incorporate chitons into their cuisines.

Finally, the incorrect answer choices in this quiz (crab, crayfish, lobster, shrimp, prawn, and barnacle) are all crustaceans that belong to the phylum Arthropoda, which are also invertebrates but will typically have bodies covered by an exoskeleton rather than a shell. Another difference between mollusks and arthropods is that the former do not have jointed appendages, while the latter do.