These animals don't even have a skull, but they are so smart that they are frightening

Review expert: Li Weiyang, a well-known popular science writer

When you think of octopuses, what characteristics do you think of? In the eyes of many people, octopuses are like this: they use water jets to quickly move in the opposite direction to avoid danger; when they encounter danger, they spray out ink-like substances like a black smoke bomb...

Octopus sprays ink

Source｜See watermark

But the characteristic I’m going to introduce today may surprise you a little bit—octopuses are the most intelligent of all invertebrates! Why are octopuses so smart?

The structure of an octopus's brain

First, let's take a look at the structure of the octopus' brain. Most creatures have only one brain, but octopuses are different. They have nine brains ! The octopus' brain has two types: the central brain and the distributed brain . An octopus has 500 million neurons, 40% of which are distributed in the central brain and the remaining 60% in the distributed brain. Can you guess what the octopus's distributed brain is? It's its tentacles! Eight tentacles are eight brains, with about 300 million neurons distributed in them.

The structure of an octopus

Source: sciencehuman.com

In addition, the functions of the octopus's nine brains are also different. The main brain is mainly responsible for thinking and memory, while the secondary brains on the tentacles are only responsible for memory. Therefore, the octopus has two sets of memory systems , which naturally makes it very smart. At the same time, each secondary brain of the octopus controls the activity of a tentacle to enhance the flexibility of the eight tentacles. The main brain gives orders to the secondary brain, and the secondary brain immediately controls the tentacle it is in to achieve cooperation, so that the eight tentacles can complete a series of coordination and operations such as unscrewing bottle caps.

Based on these characteristics, scientists have discovered that octopuses are extremely intelligent. Based on these troublesome and complex coordination and operations, scientists believe that the intelligence of octopuses can even be compared with that of humans.

So in what aspects does their wisdom manifest itself?

A genius master of disguise

The octopus can also change its color and structure like a chameleon; it is also an expert climber and camouflage master . It can use its flexible tentacles to crawl on all kinds of complex seabed terrains, sometimes disguising itself as an inconspicuous shell, and sometimes disguising itself as an anemone swaying with the sea water.

So how does the octopus achieve the purpose of camouflage? The skin of the octopus is like our storage bag, which contains various "pigments" (i.e., pigment cells), and each "pigment" is wrapped by a circular muscle that can contract and expand. When the "pigment" is pushed to the top, the skin will show the corresponding color. In other words, the octopus can control the "pigment" by contracting and relaxing its muscles.

For example, if an octopus wants to appear gray, it only needs to control its muscles so that the gray "pigment" is pushed to the top. With this ability, the octopus can achieve the purpose of camouflage by precisely controlling its muscles, making itself perfectly integrated into various environments. Doesn't it sound very cool?

Source: pixabay

At the same time, it can also simulate and transform into different creatures according to the surrounding environment. For example, when hunting, it can disguise itself as a seemingly harmless shell, waiting for the prey to slowly take the bait; when encountering a strong opponent, it can also disguise itself as the opponent's natural enemy to scare the opponent away. The title of this master of disguise is well deserved.

What does the mimic octopus want to become this time?

Source: Elias Levy CC BY 2.0

Possess thinking ability and skillful use of tools

An zoologist named Fiorito conducted an experiment in which he put small shrimps, which octopuses particularly like to eat, into a bottle and then tightened the lid. As a result, the octopus easily unscrewed the bottle cap with its tentacles and ate the small shrimps in the bottle.

At the same time, octopuses have their own way of eating shells. They first secrete a chemical substance to make the shells open. Then, in order to prevent the shells from closing again, they use their tentacles to push a small stone into the shells to block them, and finally slowly eat the meat inside the shells.

Source: pixabay

In April 2016, an interesting incident also happened at the New Zealand National Aquarium. An octopus named "InkY" successfully escaped. The aquarium where Inky was was half-open at night, so he took advantage of this omission and climbed out of the aquarium, crawled through the room, drilled into a drain, and returned to the sea after passing through a 50-meter-long pipe. This octopus that successfully escaped was really "shrewd".

After reading this, do you admire Mr. Octopus's wisdom? In the vast nature, there are still many magical creatures waiting for us to discover.