Octopus is one of the most unusual creatures that live underwater. The creature is found in the oceans and seas, it can disguise itself from prying eyes and has a lot of interesting features.
Origin of the species
Scientists cannot say exactly when the first octopuses appeared. Since their body does not contain bones, and only soft tissues are present, over time their body decomposes completely, leaving no residue.
However, in Lebanon, scientists have discovered the remains of a cephalopod, which have been preserved inside petrified rocks of the soil. Studies have shown that they are 95 million years old! And what is most surprising, in size and structure, the remains completely coincide with the living octopuses. This suggests that for such a huge time period the creation did not change.
Interesting fact: There are suggestions that the oldest representatives of the octopus species had shells, like snails, but this has not been proved.
Octopus description
Octopuses are the most numerous species of cephalopods. They are divided into two subspecies that differ in lifestyle: nomadic and bottom. The former live in the same territory, the latter regularly move underwater in search of more favorable conditions.
They are exclusively underwater creatures, they cannot live on land. Their upper shell needs constant moisture and dries quickly in air.
Appearance
Octopuses have no neck and torso, so tentacles grow immediately from the oval head. The mouth is located in the very center of the lower part, at the place of convergence of all limbs. The waste outlet is located at the back of the head.
There is a membrane between the tentacles, and they also have one to three rows of suction cups. The latter are needed in order to keep the prey and prevent it from floating away. The octopus literally sucks in food and gradually moves it to the mouth.
Interesting fact: Octopuses have a total of up to two thousand suction cups on the tentacles, which can hold an object weighing up to 200 kg.
Since their body does not contain bones, octopuses can take any form. They are able to completely flatten out along the bottom, like a piece of paper or curl up in a ball of perfect shape.
Most individuals have a pink-brown color, but are also able to change their color like chameleons. This allows you to merge with the environment and become invisible to other creatures.
Features
The octopus has many features that allow it to adapt to environmental conditions. Since it is impossible to create a vacuum in water, cephalic suckers cannot work as well as rubber analogs created by man. Because of this, the creature has to control them, tensing the muscles on the tentacles. A similar effort is made by man. when trying to draw air or liquid into the mouth.
The octopus has three hearts. Moreover, one serves for the circulatory system, and the other two are needed for the normal functioning of the respiratory system. The creatures have blue blood. Some species are capable of emitting poison, and among octopuses there are such individuals that are considered the most poisonous creatures on Earth.
Octopuses come in all sizes. Some individuals can grow up to a couple of centimeters, while others can boast dimensions of several meters. In this regard, Doflein's octopuses are especially famous: one individual grew to nine and a half meters and weighed 270 kg.
Where does the octopus live?
Creatures live in the seas and oceans, and try to find areas with warm waters, because in the cold they increase drowsiness. As a den, the octopus prefers dark places where it is easy to hide from unwanted eyes.This may turn out to be a dark bottom at great depths, a gap in the rock or an opening in a sunken ship. The easier it is to become inconspicuous in this environment, the better.
Interesting fact: sometimes octopuses can use an empty shell as a temporary den, pretending to be a crustacean.
Most often, cephalopods do not descend to a depth of more than 150 m, but sometimes people found them by sending special equipment for shooting several kilometers down.
What does an octopus eat?
These creatures are predators and are able to digest any creature found in the depths of the sea. They feed on fish, shellfish, crustaceans and even their own kind. Octopuses do not have a sense of loyalty and sympathy for their brothers, so in the famine they can eat smaller octopus without problems. Even cases were recorded when large individuals attacked sharks, and the latter could not control them.
The principle of predator hunting is quite simple. He lies at the bottom, merging with the environment, and waits for the prey to float past. Then he abruptly rushes at her and digs in tentacles. Having completely entwined food with limbs, the octopus stuffs it into his mouth. There are no teeth in the throat, but it is hard and ribbed, which helps grind the pieces into porridge.
Sometimes a predator incorrectly assesses the situation and attacks a fish that is too large. The latter can fight back and eat the offender herself or deprive him of a pair of tentacles. But cephalopods practically do not feel pain, and the limbs quickly regenerate.
How many octopuses live
These creatures cannot be called centenarians. They grow quite quickly, and their body wears out rapidly. Because of this, the average duration of octopuses is only three years.
The size and weight of the octopus
Depending on the species, underwater creatures grow from 1 cm to 4 m. Their mass can vary from several grams to 50 kg. However, there are exceptions when the creation grew to gigantic proportions.
Color
Octopus can change skin color depending on the circumstances. He does this with the help of special pigment cells located on the upper membrane. When you need to “repaint” your body in a specific color, the nervous system gives a special impulse, causing them to contract or stretch, due to which the desired shade appears.
Interesting fact: when the octopus is scared, its shell turns white, and when angry, it turns red.
Features of character and lifestyle
Octopuses can be considered night creatures. During the day, they prefer to sleep in their shelters, and when it gets dark they go hunting. They are inactive and slow, do not like to leave their territories.
Octopuses can swim, making powerful shocks with tentacles, collecting and releasing water by mouth, and moving head first. However, they do it reluctantly, because feel vulnerable during this process. At this point, they are easy to grab from either side, so octopuses prefer to move along the bottom and rocks, clinging to the surface with suction cups.
Octopuses are very clean. If there is garbage or algae around the house, they will certainly put them in a separate pile and sweep tentacles around the space.
Social structure and reproduction
Octopuses lead a hermit lifestyle, do not stray in flocks. Each individual has a territory with clear boundaries, and if an outsider crosses them, a fight will surely take place, during which only one will survive.
When you have to give birth to offspring, the female herself goes in search of the male. She does this twice a year. After the meeting of the male octopus, along with it, she goes to a secluded place, where up to 80 thousand eggs are born. From that moment, the female does not leave the shelter and takes care of the future children in every possible way. The male at this time helps his girlfriend.However, the mother always lacks food, so during this period she has a very hard time.
Four months later, small larvae emerge from the eggs, which are immediately carried away by the current and feed on plankton. They are growing rapidly, and in a few months already weigh more than a kilogram. However, not everyone can survive until adulthood, as they become food for fish and other underwater creatures.
Natural enemies of the octopus
Since they lead a predatory and aggressive lifestyle, octopuses have many enemies. They sometimes fall into the mouth of large sharks, seals, sea lions, killer whales and other large fish.
However, when a cephalopod is faced with potential danger, it has a few trump cards that help avoid a skirmish. Octopuses are able to release purple ink into the space, which completely disorient the offender. While the enemy is trying to understand what happened, the octopus quickly disappears into the nearest crevice and hides there.
Autotomy is also characteristic of creation. If the enemy grabbed him by the tentacle, it disconnects him like a lizard's tail, and calmly swims away. Scientists have long established that octopuses have high intelligence, because of which they can make the most logical and correct decisions in stressful situations. Cephalopods are also able to solve the simplest puzzles with the opening of latches and the movement of objects.
Interesting fact: sometimes a predator is an enemy to itself. Some octopuses show autocannibalism, during which they can eat their own tentacles, experiencing even a slight hunger.
Population and species status
The population of octopuses is numerous and not on the verge of extinction. They live in the seas, oceans and are actively increasing their numbers. Since people eat it, they also artificially breed it in special reservoirs.
Why is the octopus called that?
There are two versions why the octopus is called that. The first assumption, which is the most logical, is that he has eight legs. And when pronouncing the voiced consonant “in” gradually sank, which is why the word began to begin with the vowel “o”. The second theory of the appearance of the name is based on the anatomy of the cephalopod. His limbs are arranged in a circle, along the edges of the lower part of the head. Thus, they form an axis, which in combination with the word “leg” generates the corresponding name.
How many legs does an octopus have (tentacles)
The creature has eight tentacles located in a ring at the bottom of the head. Between them, inside, is the mouth. Suckers are located on the inside of the limbs, so that it is more convenient for a predator to grab his prey and eat.
Is octopus dangerous for humans?
The creature is practically not dangerous to humans. It is very cowardly and would rather run away than engage in battle. Only very large individuals will try to fight back, but people can easily cope with them.
Interesting fact: at the sight of a threat, the cephalopod can quickly swim away, developing a speed of up to 15 km / h.
Poison octopuses are the most dangerous. They use poison only in extreme cases when the enemy grabbed them tightly. If a person receives an injection, then he may have swelling and dizziness, which will soon pass. An exception are Australian individuals with particularly strong poison. Their injection can lead to the most sad consequences.
The meat is harmless to humans and contains many useful substances. In some restaurants, octopus is served even raw, and fresh meat is perfectly absorbed in the stomach.
Octopus Intelligence
Zoologists consider octopuses the most intelligent of invertebrate creatures. They are easy to learn and able to perform relatively easy tasks.Scientists put experiments on them, during which the creatures needed to take objects of a certain shape and put them into suitable holes, they coped with them perfectly.
They have excellent memory, so they can remember the environment, objects and navigate perfectly in space. Also, octopuses can remember people and become attached to them.
Types of octopuses, photos and names
At the moment, scientists have registered more than 200 species of various octopuses that have certain characteristics and habitats. However, all of them can be taken into three subspecies, combining in size, appearance and lifestyle.
Giant octopus
This octopus is found in the United States, Kamchatka and Japan. From the name it is easy to guess that he is the largest representative among his own kind. Its average dimensions reach two meters, and the mass reaches 30 kg. But the largest individuals are able to grow up to three meters and weigh up to 50 kg. Such a creature is practically not afraid of anything, because able to cope even with large predatory fish. However, it is still rather shy and prefers to flee in case of danger. It treats people neutrally and even allows you to touch yourself.
Common octopus
The most common and numerous species of these creatures. It lives in the Atlantic Ocean and the Mediterranean Sea. It can grow up to 90 cm and weigh up to 15 kg. It is this species that is used by humans for food and is bred in artificial reservoirs. Despite regular mass capture, these creatures do not feel the need to increase the population, since they produce offspring in large quantities.
Blue octopus
This type of cephalopod is the most poisonous. It is quite easy to distinguish it from the rest: it has yellow skin with large blue rings placed throughout the body. Octopuses grow up to only 10 cm in length and weigh 100 grams. A person should not be afraid of them, because they attack only in case of danger, so just don’t touch them with your hands. Blue-ringed octopuses live only near the coast of Australia, so residents of other countries are not threatened by a meeting with them.
Octopuses in popular culture and sports
In literature, octopuses have long occupied the niche of underwater monsters. The authors describe them as giant creatures attacking ships and sailors. The most vivid embodiment of such monsters is the Kraken from the films “Pirates of the Caribbean”. Also, octopuses often become heroes of art and paintings.
In sport, these creatures are not widespread. They are especially appreciated by the fans of the Detroit Red Wings hockey club, where an octopus is put on the ice before the match, symbolizing victory.
