Do octopuses live in rivers? Jellyfish, corals, polyps

Octopuses represent the class of cephalopods (Cephalopoda) known for their intelligence, supernatural ability blend with the environment, a unique style of movement ( jet propulsion), as well as splashing ink. On the following slides, you will discover 10 fascinating facts about octopuses.

1. Octopuses are divided into two main suborders

We know about 300 living species of octopuses, which are divided into two main groups (suborders): 1) finned or deep-sea octopuses (Cirrina) and 2) finless or true octopuses (Incirrina). Fin fish are characterized by the presence of two fins on the head and a small inner shell. In addition, they have antennae on their arms (tentacles) near each sucker, which may play a role in feeding. Finless, includes many of the best known species of octopuses, most of which are benthic.

2. Octopus tentacles are called arms

The average person won't see the difference between tentacles and arms, but marine biologists clearly distinguish between the two. The arms of cephalopods are covered with suction cups along their entire length, and the tentacles have suction cups only at the tips and are used to capture food. By this standard, most octopuses have eight arms and no tentacles, while two other orders of cephalopods, cuttlefish and squid, have eight arms and two tentacles.

3. Octopuses release ink to protect themselves.

When threatened by predators, most octopuses release a thick cloud of black ink made up of melanin (the same pigment that affects the color of our skin and hair). You might think that the cloud simply serves as a visual distraction to buy the octopuses time to escape, but it also affects the predators' sense of smell (sharks, which can smell hundreds of meters away, are especially vulnerable to this kind of olfactory attack).

4. Octopuses are extremely intelligent

Octopuses are the only marine animals, other than whales and pinnipeds, that are capable of solving certain problems and recognizing various patterns. But regardless of octopus intelligence, it is very different from human intelligence: 70% of an octopus's neurons are located along the length of its arms, not in its brain, and there is no conclusive evidence that these are capable of communicating with each other.

5. Octopuses have three hearts

All vertebrates have one heart, but octopuses are equipped with three: one that pumps blood throughout the octopus's body (including the animal's arms), and two that pump blood through the gills that they use to breathe underwater. There is another key difference from vertebrates: the main component of octopus blood is hemocyanin, which contains copper atoms, rather than iron-containing hemoglobin, which explains the blue color of octopus blood.

6. Octopuses use three modes of locomotion

A bit like an underwater sports car, the octopus moves with three different ways. If there is no need to rush, they walk along the ocean floor using their flexible tentacle arms. To move faster underwater, they actively swim in the desired direction, bending their arms and body. In the event of a real hurry (for example, an attack by a hungry shark), octopuses use jet propulsion, throwing a stream of water (and ink to disorient the predator) from the body cavity and move away as quickly as possible.

7. Octopuses are masters of camouflage

Octopus skin is covered with three types of specialized cells that can quickly change color, reflectivity and transparency, allowing the animal to blend into its environment. Pigment-containing cells - chromatophores - are responsible for the red, orange, yellow, brown, white and black colors of the skin, and also give it shine, which is ideal for camouflage. Thanks to this arsenal of cells, some octopuses are able to disguise themselves as algae!

8. The giant octopus is considered the largest species of octopus

Forget all the movies about octopus monsters with tentacles as thick as tree trunks that sweep helpless sailors overboard and drown them. big ships. The biggest known species octopus - giant octopus (Enteroctopus dofleini), weighs on average about 15 kg, and the length of the arms (tentacles) is about 3-4 m. However, there is some dubious evidence of significantly larger individuals giant octopus, weighing more than 200 kg.

9. Octopuses have a very short lifespan

You may want to reconsider buying an octopus as a pet because most species have a lifespan of about a year. Evolution has programmed male octopuses to die within weeks of mating, and females stop feeding while waiting for the eggs to hatch, and often starve to death. Even if you sterilize your octopuses (most likely, not every veterinarian in your city specializes in such operations), it is unlikely that your pet will live longer than that of a hamster or gerbil mouse.

10. The octopus order has another name

You may have noticed that in this article only one term was used, “octopuses,” which is familiar to everyone and does not hurt the ears. But this order of cephalopods is also known as octopus (octopus in Greek means “eight legs”).

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Anatomy and physiology

The body of octopuses is short, soft, and oval at the back. The mouth opening is located where its tentacles meet, and the anus opens under the mantle. The mantle resembles a wrinkled leather bag. The octopus's mouth is equipped with two powerful jaws, similar to the beak of a parrot. The pharynx has a grater (radula) that grinds food.

The head bears eight long tentacles - “arms”. The “hands” are connected to each other by a thin membrane and have from one to three rows of suckers. On all eight tentacles of an adult octopus there are about 2000 of them, each of which has a holding force of about 100 g, and, unlike those created by man, the octopus’s suction cups require effort when holding, and not when sucking, that is, they are held only by muscle effort.

Octopuses have unusual ability- due to the absence of bones, they can change shape. For example, some octopuses, while hunting, lie flat on the bottom, masquerading as flounder. They can also freely pass through holes with a diameter of 6 centimeters and remain in a limited space that is 1/4 of the body volume.

Nervous system and sensory organs

Color

The common octopus has the ability to change color to adapt to its environment. This is explained by the presence in his skin of cells with various pigments that, under the influence of impulses from the central nervous system, can stretch or shrink depending on the perception of the senses. The usual color is brown. If the octopus is scared, it turns white; if it is angry, it turns red.

Size and weight

The length of adults varies from 1 centimeter (in males of the species Argonauto argo) up to 4 meters (at Haliphron atlanticus). The mass of octopuses reaches 50 kg. There is evidence that Doflein's octopus can reach a length of 960 cm and a weight of 270 kg.

Lifespan

Rarely exceeds 5 years, on average 1-3 years.

Habitat and distribution

Thanks to their soft, elastic bodies, octopuses can penetrate holes and crevices much smaller than their normal body size, allowing them to hide in sophisticated ways in all sorts of shelters. They even settle in boxes, cans, car tires and rubber boots. They prefer shelters with a narrow entrance and a spacious room. They keep their home clean: they “sweep” it with a stream of water from a funnel, and put scraps outside in a garbage heap. When enemies approach (including divers or scuba divers), they flee, hiding in rock crevices and under stones.

As they flee, octopuses of many species release streams of ink, a dark liquid produced by special glands. This liquid hangs in the water in the form of shapeless translucent spots and remains compact for some time until it is washed away by water. Zoologists have not yet reached a consensus on the purpose of this behavior. Cousteau, in his book “In a World of Silence,” suggested that these spots are a kind of decoys, designed to divert the attention of the attacker and allow the octopus to gain time to hide.

Octopuses have protective device- autotomy: a tentacle grabbed by an enemy can come off due to strong contraction of the muscles, which in this case tear themselves apart. The severed tentacle continues to move and respond to tactile stimuli for a certain time, which serves as an additional distraction for the predator of the pursuing octopus.

Many species overwinter in more deep waters, and in summer they move to shallow water.

Intelligence

Octopuses are considered by many zoopsychologists to be the most “smart” among all invertebrates in many respects: they can be trained, they have good memory, distinguish geometric figures- a small square is distinguished from a larger one; a rectangle placed vertically from a rectangle placed horizontally; a circle from a square, a rhombus from a triangle. They get to know people and get used to those who feed them. If you spend enough time with an octopus, it becomes tame. Excellent trainees. Nevertheless, an accurate assessment of the level of intelligence of octopuses is a subject of debate among zoologists due to the main ability of adaptive perception of the central nervous system. In other words, octopuses can program their brains for a specific task.

Social structure

Loner, territorial. Often lives next to octopuses of the same size.

Reproduction

The nest is a hole in the ground, lined with a rampart of stones and shells. The eggs are spherical, connected in groups of 8-20 pieces. After fertilization, the female makes a nest in a hole or cave in shallow water, where she lays up to 80 thousand eggs. The female always takes care of the eggs: she constantly ventilates them, passing water through the so-called siphon. She uses her tentacles to remove foreign objects and dirt. During the entire period of egg development, the female remains at the nest without food and often dies after the young hatch.

Eating

Eating octopus is common in many cultures. In Japanese cuisine, octopus is regular product, from which dishes such as sushi and takoyaki are prepared. They are also eaten alive. Live octopuses are cut into thin pieces and eaten within a few minutes while the tentacle muscles continue to convulse.

Evolution and phylogeny

Classification

Negative attitudes towards octopuses are reflected in fiction. Victor Hugo in the novel “Toilers of the Sea” especially colorfully describes the octopus as the embodiment of absolute evil.

This creature is approaching you with many vile mouths; the hydra merges with man, man merges with hydra. You are one with her. You are a prisoner of this nightmare come true. A tiger can eat you, an octopus - it's scary to think! - sucks you out. He pulls you towards himself, absorbs you, and you, bound, glued together by this living mucus, helpless, feel how you are slowly pouring into the terrible bag that this monster is.
It is terrible to be eaten alive, but there is something even more indescribable - to be drunk alive.

Octopuses have been somewhat rehabilitated with the proliferation of scuba gear. Jacques Cousteau, who was one of the first to observe octopuses in their natural environment habitat, in the book “In the World of Silence” this is how he describes the first attempts to become acquainted with these creatures.

It was this idea of the octopus that dominated us when we first penetrated into undersea world. However, after our first encounters with octopuses, we decided that the words “drunk alive” apply more to the state of the author of the above passage than to the person who actually met the octopus.
Countless times we have put ourselves at risk of falling victim to the octopuses' addiction to unusual drinks. At first we felt a natural disgust at the thought of having to touch the slimy surface of rocks or sea animals, but we quickly became convinced that our fingers were not so scrupulous in this regard. So, for the first time we decided to touch a live octopus. And there were a lot of them all around, both at the bottom and on the rocky slopes. One day Dumas plucked up courage and took the bull by the horns, that is, he pulled the octopus off the cliff. He did this not without fear, but he was reassured by the fact that the octopus was small, and Dumas was clearly too big a mouthful for him. But if Didi was a little cowardly, then the octopus himself was simply in a panic. He squirmed desperately, trying to escape the four-armed monster, and finally broke free. The octopus ran away in leaps and bounds, pumping water through itself and throwing out streams of its famous ink liquid.
Soon we were boldly approaching cephalopods of all sizes.

There is no reliable evidence of octopus attacks on humans, however, certain species pose a serious danger due to poisonous bites, to which they can be provoked by a person persistently trying to get into contact with them.

In 1814, the Japanese artist Katsushika Hokusai published the print “The Dream of the Fisherman’s Wife,” which depicts two octopuses and a woman. Engraving has gained great fame throughout the world and over the centuries.

In the second episode of the TV movie “Wild Future” (100 million years in the future) there are swamps - land descendants of octopuses.

The image of an octopus sucking out brains was used in the first episodes of the 4th season of the television series Grimm.

Who are octopuses

To determine exactly what octopuses are (they are also called octopuses) and find out which group they belong to, you need to remember general rules classification of all living beings. This is done by a special science – systematics. Based on similar characteristics, all living beings are united into kingdoms, which are divided into types. Those, in turn, are divided into classes, orders, species and genera. A genus is the lowest systematic unit; those similar in a number of characteristics of the genus are combined into species. Many factors are taken into account when determining a specific position in the classification table.

Animals, from a taxonomy point of view, are all multicellular organisms that move and feed on plants or other animals. An octopus is clearly an animal; its body is multicellular and complex. The other criteria are also suitable: it moves well, not only in water, but also on land. And it is a predator - it hunts other fish, crabs and various sea creatures.

Then the division into types begins. The subkingdom of multicellular organisms is divided into main groups according to a certain characteristic, depending on the complexity of the structure of their organism. Chordates, those with a skeleton, are considered complex from an anatomical point of view. Its absence provides grounds for inclusion in another group. For example, fish have a skeleton, but octopuses do not. They are accordingly included in different types. Fish are chordates, octopuses are molluscs. Despite the fact that they live in the same element, these are already different groups, so octopuses are definitely not fish. Although they have a similar feature: they breathe oxygen dissolved in water through their gills. But gills are not the characteristic by which these two types can be combined into one.

Chordata are divided into classes. The class of mammals has the most complex structure of the body. It is grouped according to its main characteristic – the method of feeding offspring. If it is fed with milk, the animal is uniquely assigned to this class, regardless of the method of movement, habitat, size and appearance. For example, marine life dolphins are mammals. But octopuses do not belong to this class. First of all, they aren't even chordates. Secondly, they do not feed their offspring milk.

The place of octopuses in the classification table is as follows:

kingdom: animals;
type: shellfish;
class: cephalopods;
squad: octopuses.

Next comes the division of genera and species. Despite the difference in size, external signs and habitat, all representatives of the octopus order have the same structure, principles of nutrition, reproduction and other unifying characteristics. Thus, the large Doflein octopus in body structure is not fundamentally different from the mini version - the species Argonauto argo, the adult male of which is only 1 cm in length.

Interesting fact: the Doflein giant is amazing in its size. But after birth, mollusks of this species do not exceed 4 cm.

Amazing cephalopods

So, everything is clear with the classification from a systematic point of view. Octopuses are invertebrates divided into a separate class - cephalopods. But if we consider octopuses from the point of view of their similarity with other representatives of the fauna, then we can find many unifying characteristics.

Surprisingly, cephalopods there are similarities with the most different representatives fauna:

They have gills, just like fish. And in the oral cavity there is a beak, which is similar to the beak of a parrot.
They can change color like chameleons. And to disorient predators, they release a protective cloud of ink, like their closest relatives - cuttlefish.
In case of danger, they are ready to “give the enemy” their leg and grow a new one (like a lizard’s tail).
They have the ability to mimicry, imitating the environment, objects, and other marine inhabitants, for example, like praying mantises. And in case of danger, they depict exactly the predator that will scare off the attacker ( different types capable of depicting copies of 24 species marine organisms, from jellyfish to stingrays and sea snakes). Octopuses are capable of depicting very unusual objects. Thus, a case was recorded when a caught octopus copied the newspaper on which it was placed.
They can move on land for some time, that is, live in two environments like amphibians: octopuses have a special reservoir for water, it is located in the mantle cavity, the supply of oxygen lasts for an average of 4 hours.
They perceive ultrasounds as the bats and dolphins. Despite the lack of ears, they hear quite well, like many land animals.
They are tamed, trained, able to distinguish between pictures and people, and perform simple tasks; their intelligence is determined at the level of dogs and crows.

They have a developed sense of direction: being on land, they perfectly determine the shortest distance to the sea. This instinct is somewhat reminiscent of the ability to navigate in migratory birds. Some species travel across seas and oceans, but return to a specific area to reproduce, like fish to spawn.
They have fairly sharp eyesight; their vision can cover 360 0 . These mollusks have the rudiments of binocular vision.
Cephalopods kill their prey with poison (it is usually not dangerous for people, with the exception of poison in representatives of the genus Blue-ringed, which has a nerve-paralytic effect). The poison contains substances that can soften the crab's shell. This mechanism is reminiscent of the feeding pattern of some spiders; their enzymes dissolve the chitinous membranes of insects. And has a paralytic effect, similar enzymes in digestive tract predators are common.
They take care of their offspring. In nature, parental instincts are not uncommon, especially in highly organized organisms. Female octopuses guard the clutch of fertilized eggs, while they themselves refuse to feed during this time and can starve for 4 months (usually dying as a result). Which is reminiscent of the “diet” of male penguins, who hatch a single egg and go without food during this entire period.

These amazing octopuses live in sea depths! In their arsenal there are different mechanisms that are typical for other representatives of the fauna. Octopuses are also capable of:

hold food with the power of suction cups, each of which is capable of holding any object weighing 100 g;
excellent at identifying edible and inedible objects using taste buds located on the tentacles;
clean your home, throwing out garbage and putting it in garbage heaps;
regulate heart rate depending on water temperature;
adapt to conditions environment: shining example– replacement of the ink cloud of deep-sea inhabitants with a cloud of luminous symbiotic bacteria, which in the darkness at depth blinds the enemy;
transform its leg into a reproductive organ: one tentacle of the male becomes a hecocotylus containing sperm, depositing sperm into the mantle of the female (and in some, the hecocotylus breaks away from the body and fertilizes her on its own).

A few more facts:

Cephalopods have 3 hearts, one ordinary, three-chambered, and two small gills;
their blood is blue due to hemocyanin, which replaces hemoglobin;

Octopuses are cephalopods. In the order of animals "octopuses" there are 200 various types. Their closest relatives in this type are considered to be squid and cuttlefish. The most distant include all gastropods and bivalves.

Octopus appearance

At first glance, its appearance may be puzzling. But in the end everything turns out to be simple and clear, where he is and what parts of his body are located. The body itself is shaped like a bag and is called the mantle. At the front it is connected to big head with two bulging eyes located on it. Their mouth is very small. Around the mouth chitinous jaws, which are called a beak. With the help of this beak, octopuses grind food, because they cannot swallow it whole. In addition, a little further in the throat, they have a special grater. With this grater, octopuses grind food that has not yet been chewed with its beak into pulp. The anus is hidden under the mantle.

There are tentacles around the mouth, of which there are always 8 pieces. The tentacles of the octopus are very long and with muscles, and are covered below big amount suckers different sizes. Suckers are located on the tentacles in 1-3 rows. With one suction cup alone, due to the work of the muscles, without taking into account adhesion, the octopus can hold approximately 100 grams of weight. The tentacles are united by a small membrane called the umbrella. About 20 existing species Octopuses have small fins on both sides. In these species, the fins are used as a rudder, and not for pushing off the water and moving around.

Under the eyes of the octopus is siphon, which looks like a short tube or small hole. Using a siphon, water is drawn into the mantle cavity. Using the contraction of the mantle muscles, the octopus forcefully pushes water out of the mantle cavity, which moves its body. To change direction, he turns the siphon and pushes the water in the other direction. On a hard or vertical surface in water, octopuses move by crawling, using tentacles.

They have blood blue color due to hemocyanin. This is a special pigment that replaces hemoglobin. Gills are hidden in the mantle cavity and are necessary not only for breathing, but also for excreting waste products. They also have a special ink sac that accumulates a protective coloring substance.

The largest octopuses grow up up to a length of 3 meters and 50 kilograms of weight. The most common types are from 0.2 to 1 meter in length. The only exceptions are males from the Argonaut species. They are much smaller than the females of their species, rarely growing even to 1 cm in length.

Due to the lack of bones, these animals can easily change shape and stay in confined spaces.

Octopus sensory organs

Among invertebrates Octopuses are considered the most highly intelligent. All their senses are highly developed. The most perfect among the body parts are the eyes. They are not only large in size, but also very difficult to work with. Fundamentally, the way images are formed in the eyes of an octopus and a person does not differ. The octopus sees its own image with each eye. But if necessary, in order to look at something more closely, they can bring their eyes closer and focus on the object.

Corner vision their bulging eyes almost extend to 360 degrees. The eyes have a lens with an outward oriented retina. The shape of the pupils is rectangular. The skin is all covered with light-sensitive cells, by which they can determine which direction the light is coming from.

Taste receptors are located on the suction cups, on the tentacles. They do not have special organs for hearing, but they have the ability to hear infrasounds. Their skin is usually brown, red or yellow. Although, depending on the situation, they can change skin color like chameleons. The principle of color change is the same as in reptiles. The current color is directly dependent on the well-being or mood of the animal, as well as on the environment. When frightened, his skin becomes paler, and when angry it can turn red or even blacken.

An interesting fact is that the change coloring has a direct dependence on visual perception. If you blind an octopus, it will lose the ability to change color. If you blind him in one eye, he will change color only on the side of the body on which he sees. Tactile, light-sensitive cells on the skin also play a small role.

These animals bear offspring only once in their lives. The periods when they breed fall in April and October. In some cases, the dates are shifted and fall into June and October. Although they live on average no more than 2 years. Some time before the mating season in males, one of the tentacles transforms into an organ necessary for reproduction. This organ is called " hectocotylus".

Using his new organ, the male transfers the reproductive cells into the mantle cavity of the female. After this, the female lives a normal life for several more months. Only after a long time does she begin to lay eggs. In one clutch there may be a large number of eggs: from 40 to 190 thousand pieces.

After laying eggs, the female becomes the most caring animal towards her future children. Sometimes the female has to wait up to 4 months for the larvae to appear. All this time she does not leave the eggs, cleans them of debris and protects them from other sea animals. It often happens that a female, exhausted from hunger, cannot stand it and dies. Males, after they pass on male reproductive cells, also die.

Larvae that hatch from eggs are already independent from the first days of life.

What do octopuses eat?

Basic food for octopuses are the following types sea animals:

Fish;
crustaceans;
shellfish

Based on their feeding method, benthic species can be classified as lurking predators. They use this type of hunting, since octopuses are not adapted to move or swim quickly. Hiding in a secluded place, they wait with great patience for some fish, crab, lobster or lobster to swim nearby. Then in right moment sharply rush at them, covering them with their tentacles. So that you can’t escape.

Kamchatka crabs are their favorite food. Having caught the crab, the octopus pinches it with its tentacles from all sides and takes it to its shelter. There are times when an octopus manages to catch and drag away several crustaceans at once. They also prefer to hunt bulls and flounders. Using suction cups on the tentacles, they capture prey. One suction cup with a diameter of about 3 centimeters can support 3 kilograms. And since the octopus has hundreds of these suckers, the force will be great.

All species of these cephalopods belong to predatory animals. Before eating their prey, they capture it with their tentacles and kill it with poison. Animal shells are broken by the beak, which is located near the mouth. Also, each octopus has very distinct preferences in food and in the methods of obtaining this food.

The main enemies of octopuses

The main enemies include the following animals:

Dolphin;
sea lion;
seal;
moray eel;
shark;
bird;
a larger individual.

If the octopus senses or notices an enemy, it will first try to defend itself. Firstly, it will try to “escape” on half-bent tentacles or slowly swim away. If he is scared, he can jerkily increase his speed up to 15 km/h. Then it will look for somewhere to hide or camouflage itself by changing its color. They camouflage themselves into the surrounding landscape even when they are not in any danger. If the soil is soft, they bury themselves in the sand. If the fear is very strong, then a dark-colored liquid is released, with the help of which the enemy is disoriented. Can sacrifice a tentacle to an enemy if it is grabbed and there is no way to escape.

We will talk about such an animal as the octopus, find out where it lives, what kind of lifestyle it leads, what others eat Interesting Facts, which will introduce you more closely to this marine inhabitant.

Main characteristics

Marine animals, octopuses, prefer to live at the bottom of seas and oceans and can exist exclusively in water. To survive in such conditions, there is a special flexible soft body with eight tentacles.

With the help of suction cups, it can move along the seabed, rocks and stones, and grab prey.

Thanks to them, he is able to determine the edibility of a product - there are up to 10 thousand taste buds on the suction cups. Between the tentacles there is a mouth shaped like a parrot's beak and is capable of grinding food.

The size of octopuses depends on their species and age. Its size can vary from 1 cm to 4 m in adults. Average duration life is 2 years. There are cases when the animal lived up to 4 years.

Weight can reach up to 50 kg. Octopus is an animal with 3 hearts. One is the main one, and the rest are intended for the gills, dispersing blood. Octopuses are the most smart creatures among invertebrates.

There are more than 200 species of octopuses. The closest relatives of mollusks are squid and cuttlefish. Thanks to a special pigment called hemocyanin, octopus blood is blue. The mollusk is able to change color and camouflage itself with surrounding objects for the purpose of protection.

The main color is brown, but in a critical situation it takes on a color depending on the occasion. This is also an indicator of his condition. When a clam is frightened, it becomes white, angry - red, and in a dream they turn yellow.

Habitat of the octopus

Octopuses are quite resistant to any climate, due to which they live all over the world, where there is salty water from 30%, except in the north. They prefer to live separately and not encounter their relatives.

They reproduce 2 times a year, in autumn and spring, connecting with tentacles. After a week, the female can lay up to 80 thousand eggs, which will lie for up to 5 months until the cubs hatch.

They can live in shallow water and depths of up to 150 meters, but other species prefer deep water and can settle at a depth of 5000 m.

Octopuses prefer rocky terrain, settling in cracks and caves for living. Marine animals try not to leave their shelter, lead a sedentary lifestyle and hunt near their home. They are able to build their own nest where they can hide from others. dangerous inhabitants depths, collecting pebbles and corals together.

Octopuses are nocturnal inhabitants and do not leave the reefs during the day, going out at night to get food. The diet includes plankton, fish, crayfish and other shellfish. They sleep with with open eyes and only the pupils narrow. There are species of octopuses that are active and mobile. They spend time in motion during sleep and constantly move along the plane of the water.

Protecting the octopus from dangerous representatives of the underwater world

Mollusks are able to fight for life to the last, trying to escape by any means. Their body is capable of doing unimaginable things to escape from the enemy:

1. They have high speed movement. During periods of danger, the body can accelerate to 16 km/h. They are able to move backwards, thanks to the structural features of the body. Water enters under the head in the form of a bag and is jerked out from there under pressure, moving it over long distances.

2. With the help of a flexible and plastic body without bones, they can fit into the narrowest and most inconvenient places where a predator cannot reach.

3. The octopus is capable of taking on any color, masquerading as the surrounding area and other inhabitants of the seas and oceans, choosing the image that is most terrible to the enemy. Even when he is safe and calm, he repaints himself to match his surroundings to eliminate the slightest possibility of being discovered.

4. They release chemical weapon in the form of a dark liquid that robs the enemy of his sense of smell and deprives him of his sight. The shape of the released liquid for some time has the outline of the octopus itself.