The octopus has 3 hearts and 9 brains.

Most animals have only one brain, but the octopus has 9 brains, one of which is the main brain and the other 8 are secondary brains. Among them, the main brain is the most important one, which has two main roles, one role is to think; the other role is the role of memory, because this main brain is connected to a memory system. The main role of the parabrain is to memorize.

In addition to having 9 brains, the octopus also has 3 hearts. One of them is the "body heart", this heart plays a major role in blood supply to the whole body of the octopus; there are two is the "gill heart", they can also play a part of the role of blood supply, but their main role is not to supply blood, but to filter the waste produced by the body. The gills are also used to supply blood to the body.

Breeding

Octopus in the ocean breeding time is generally concentrated in the spring and fall, spring and fall seawater temperature of about 16 ℃. Octopus like to spawn in the conch shell, so the rope can be threaded through the red conch shell sunk to the bottom of the sea, extracted in time to catch. Autumn and winter often burrow in deeper waters in the sediment.

Octopus dioecious. The male has a specialization of the wrist, known as the stem wrist or handing wrist, used to put the sperm packet directly into the female body of the coat cavity. Whenever the breeding season, the female octopus spawns eggs, about 0.3 centimeters long, totaling more than 100,000, which are laid under rocks or in caves. The female guards the eggs during incubation, using a suction cup to get the eggs clean and stirring them with water.

Female octopuses need the young to hatch 4-8 weeks after a one-time egg laying. The juvenile octopus is shaped like an adult but small, and after hatching they need to drift with the plankton for a few weeks before sinking to the bottom and hiding.