Octopus, also known as octopus, is a mollusk, which evolved from cephalopods. Generally, the body is very small, and the eight tentacles are thin and long, so it is also called "Octopus".

Octopus, like the familiar cuttlefish, is not a fish, but a mollusk. What is unusual is that octopus has eight feet as long as a belt, which meanders and floats in the water, so it is also called "octopus".

Morphological characteristics:

Octopus is the "overlord" in the ocean. It is extremely powerful, cruel, aggressive and resourceful, and many marine animals are afraid of it. Octopus is a sensitive animal, and its nervous system is the most complex and advanced among invertebrates, including central nerve and peripheral nerve, and it is divided into auditory nerve, olfactory nerve and visual nerve at the cerebral ganglion. The most developed of its sensory organs is the eye, which is not only big, but also bulging and motionless.