With eight arms, three hearts and a knack for learning, octopuses are quite the creatures!

When they think of octopuses, many people automatically call to mind animals with eight legs and suction cups, but there’s a lot more to these invertebrates. Today is World Octopus Day, and we’re celebrating by shedding some light on these marine mollusks.

Octopuses are members of the class Cephalopoda, which means “head foot” in Greek. They have eight equally long arms that surround their head, which they use to “walk” on the seafloor!

Octopuses also have hard beaks employed to pierce the shells of their prey with hard outer shells, like crustaceans. These solitary creatures don’t lack a heart—they have three! Two hearts work exclusively to move blood to the gills and the other pumps blood through the rest of the body.

In addition to having eight arms and three hearts, the octopus is also highly intelligent—they can figure out how to open clams, mussels and even jars! They are also incredibly flexible, great at hiding and very crafty hunters.

Octopuses reside in every ocean in the world, and the common octopus is one of the most abundant species off our coast. The common octopus can grow up to three feet and weigh between six and 22 pounds.

Due to their solitary nature and incredible ability to camouflage, it is difficult to determine the status of their population. Although not considered endangered, the common octopus is sensitive to pollutants, so make sure to adhere to the fertilizer ban during the rainy season, pick up after your pets and minimize pesticide use.

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