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Mollusca Phylum

What are the defining characteristics of mollusks?

The phylum Mollusca consists of many kinds of brightly colored sea slugs. All the pretty and unusual shells you might find at the beach are the remains of mollusks. The shy, smart octopus with human-like eyes and the fast, graceful squid are also mollusks. What do mollusks look and act like? Watch this video to find out!

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Have you ever eaten an oyster?

How about clams or mussels?

If so, then you have eaten mollusks!

With over 100,000 different species existing on Earth …

the organisms in the phylum Mollusca can be found from the high elevations …

to the depths of the ocean.

You’ve probably seen a snail outside, foraging for food …

or a slug creeping along on a wet day. There are many different types of snails and slugs …

and they live on land or in fresh or saltwater.

People even eat some land snails!

This hungry octopus foraging for its next meal is also a mollusk.

So are these glowing squid …

and these hovering cuttlefish.

This chiton is a type of mollusk living in the intertidal zone, the area where the land meets the sea.

From a slow-moving snail to a squid that can zip away to safety, mollusks are all around us.


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Question

Which animals are classified as mollusks?

Garden slugs, sea slugs, snails, octopuses, clams, and mussels are just a few animals that are classified as mollusks.