The marine "miracle" with 3 hearts and 9 brains/ Facts you didn't know about octopuses

2026-02-24 22:02:00, Kuriozitete CNA

The marine "miracle" with 3 hearts and 9 brains/ Facts you didn't

Octopuses are among the most impressive and at the same time most underrated animals on the planet.

Although the "reputation" for intelligence is often enjoyed by monkeys, elephants, dolphins or crows, octopuses are true "intelligences" of the seabed, with distinct personalities and unique biological characteristics.

Here are some of the most impressive facts about octopuses:

Nine "brains" and 500 million neurons

The octopus is considered one of the smartest animals in the world. The average octopus has about 500 million neurons - a number that puts it on par with the smallest mammals.

However, unlike mammals, most of the octopus's neurons are not located in the central brain, but in its tentacles. In fact, there are twice as many neurons there, which often leads to the comparison that the octopus has one brain in each tentacle - that is, nine "brains" in total.

Good memory and learning ability

Since the mid-20th century, research has shown that octopuses can be trained. In experiments, they were able to pull a lever to receive a piece of sardine as a reward.

These are animals that can solve complex problems, use tools, and transmit skills to each other. In vision tests, where they were asked to remember simple actions by closing one eye and then the other, they performed better than many other animals, including pigeons.

They know people.

In a laboratory in New Zealand, a case was recorded of an octopus showing a clear dislike for a certain staff member, licking the back of her neck whenever she passed by.

They have three hearts.

The octopus has three hearts. Its blood is blue-green because it uses copper to transport oxygen instead of iron, as it does in humans.

Color change and impressive "poses"

Octopuses can change color and pattern. An aggressive male may darken, rise from the bottom, and spread his tentacles to appear larger.

Without a skeleton, but with an advantage

The lack of a skeleton or shell makes the octopus vulnerable to predators. However, this same feature allows it to hide in incredibly small spaces. It can fit through an opening the size of its eye and adapt its body to almost any shape.

Octopuses prove that intelligence and complexity are not limited to mammals. With unique nervous systems, distinctive behaviors, and impressive biological properties, they are one of the most fascinating creatures in the marine world. /CNA