Octopus

Octopus
Octopus vulgaris, the common octopus
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	Coleoidea
Superorder:	Octopodiformes
Order:	Octopoda
Suborder:	Incirrina
Family:	Octopodidae
Genus:	Octopus

Octopus ^[1] is a genus of cephalopod mollusc in the order Octopoda. The genus is quite typical of most octopods. They have two, large eyes and eight limbs with suckers. They have a hard beak, with the mouth at the center point of the arms.

Octopods have no internal or external skeleton, allowing them to squeeze through tight places and hide. Many stays in cracks between rocks or corals when they are not hunting. They are intelligent predators with a taste for crabs. Octopuses have three hearts. Two pump blood to the gills, while the third pumps it to the rest of the body.^[2]

Octopods inhabit many regions of the ocean, especially coral reefs. For defense against predators, they hide, flee quickly, expel ink, or use colour-changing camouflage. They live rather short lives.

An octopus trails its eight arms behind it as it swims. All octopods are venomous, but only the small blue-ringed octopus is known to be deadly to humans.^[3]

There are about 300 octopod species, of which more than 100 are in the genus Octopus. Octopods make up over one-third of the total number of living cephalopods. The term 'octopus' may be used to refer to those in the genus Octopus. The term 'octopod' is correct for members of the order Octopoda in general.

1. ↑ The plural of Octopus is usually octopuses. For members of the order Octopoda in general, 'octopods' is the term used. (Greek: okto = eight; podes = feet).
2. ↑ "Why Do Octopuses Have Three Hearts?". ScienceABC. 2020-02-29. Retrieved 2024-08-16.
3. ↑ Unimelb.edu.au Archived 2011-10-06 at the Wayback Machine Tentacles of venom: new study reveals all octopuses are venomous, University of Melbourne, Media Release, Wednesday 15 April 2009