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Squids, octopi, nautili & cuttlefish



Category: Invertebrates



These ocean dwelling animals are characterized by bilateral body symmetry, a prominent head, and a set of arms, or tentacles. There are about 800 identified species of cephalopods, a class that includes squid, octopi, nautili, and cuttlefish. With their well-developed senses and large brains, cephalopods are widely considered the most intelligent of the invertebrates. With only a few exceptions, all cephalopods have an ink sac, which can be squirted into the surrounding water to confuse predators. They are also the only mollusks with a closed circulatory system.



Data & Facts

Scientific Classification
Kingdom - Animalia
Phylum - Mollusca
Class - Cephalopoda

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Interesting Animal Facts

Cephalopods: Masterminds of the Ocean.

Octopi, cuttlefish, and squids - all cephalopods - have been observed engaging in amazing feats of intelligence (perhaps unsurprising, as cuttlefish and octopuses have the highest brain-to-body mass of all invertebrates). Their suction-cup covered arms are dexterous, and octopuses have been observed putting them to use throwing rocks, opening screw-top jars, even picking up and gathering coconut shells to build fortresses for themselves. Squids, for their part, have been observed hunting cooperatively and are able to communicate with one another via color changes, patterns, and flashing to one another - sometimes using different sides of their bodies to broadcast different signals to multiple squids! Just how smart are they? As they are typically elusive and so very different from humans, we aren’t sure yet - but we do know the question is not “Are they intelligent?” but “How intelligent are they?”

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