Why are octopus aliens?

First of all, their physiological structure is very strange. Octopus has three hearts, two of which are responsible for supplying blood to gills (gill heart) and one is responsible for supplying blood to the whole body (body heart). They also have parrot-like beaks and eight arms full of nerves and suckers.

Octopus has three hearts: two gills and one heart.

They have no skeleton, and the only hard place is their beaks, so they can get through an extremely narrow space by twisting their bodies extremely and become masters of escape.

The octopus escaped from the boat through a crack the size of a wrist and toe.

Secondly, the "IQ" of octopus is different among invertebrates-compared with other invertebrates, they are extremely intelligent.

Octopus has two memory systems, one is the brain memory system (accounting for 40% of all nerve cells), and the other memory system (accounting for 60% of all nerve cells) is directly connected to the sucker. We humans only have a brain memory system. If our limbs want to complete more complex movements, the brain must be responsible for controlling the specific operation steps. Octopus, however, has independent nerve cords in its eight brachiopods, which can accomplish many complicated tasks independently. Octopus lacks the long-term connection between brain and wrist, so they often "can't control themselves".

If the octopus wants to return to the sea, its brain only needs to give an abstract "homing" command to the wrist foot, and how to complete it is judged and decided by the wrist foot, and it does not need the brain to control every action detail. Although human spinal cord can also complete some low-level reflexes (such as knee jerk reflex and hand retraction reflex), the degree of autonomy of octopus brachiopod nerve is much higher than that of human.

Scientists have also tailored some experiments for octopus to see if it has the ability of memory and learning. Facts have proved that octopus, like human beings, also has the ability to remember and learn!

The researchers put a crab in a bottle, and then put the bottle in a complicated glass box. Next, they fished a new octopus novice from MengMeng out of the water and put it in the water tank. Facing the complicated glass box, the novice octopus can only stare blankly. There is an octopus living next door to him. It always bumps around and skillfully takes food from the same glass box. When the novice octopus saw it, he immediately took the same method and caught the crab.

In addition, octopus likes to play (repeatedly throwing toys into the water and then catching them back), can use tools (when predators approach, grab coconut shells and run to give themselves a hiding place), can walk mazes and remember roads (which makes many "road-mad" humans believe in it. . . ) and so on.

Imitate, learn, play, use tools, etc. It is the characteristic of higher mammals like humans. As an invertebrate, the performance of octopus is really staggering!

Third, stealth +72 change

Octopus has another stunt: duang~~ invisibility. It can quickly change colors and textures and hide itself in the surrounding environment, just like wearing an invisibility cloak. It also "seventy-two changes" (mimicry), imitating a highly toxic creature to scare natural enemies.

Their ability is closely related to the pigment on the skin and muscle regulation. Octopus skin has three layers, the first layer is pigment cells, the second layer is iris pigment cells, and the third layer is colorless cells.

There are many pigment sacs in the top pigment layer, and there is a circle of muscle around each pigment sac. As long as the muscles contract together, the small pigment spots are pulled into large color blocks. The middle iridescent layer is composed of many thin layers with horizontally arranged cells. Stimulated by nerve signals, the brightness of polarized sequins can be reflected by adjusting the angle and thickness. The bottom white layer is the simplest, that is, there are ultra-white reflective proteins in the cells, which can reflect almost all visible light.

Last but not least! Their genes are special. What is a gene? Gene is the carrier of genetic information, which consists of DNA that determines the characteristics of species and is stored in the nucleus of each cell. Children look like their parents because their genes have been passed on to them. In cells, genes are transcribed into RNA, and RNA is translated into protein. Finally, protein directly participates in the regulation of our organism's life activities. This process is called the "Central Rule".

Simply put, if the human body is compared to a computer, a piece of DNA is equivalent to a piece of "source code" of biological genetic information, RNA is equivalent to the corresponding "copy code", and protein is the result of running the "source code". The copied code will be cleared after running and then "copied" in the next run. It can be seen that the change of "source code" DNA will be passed on to the next generation, while the change of "copy code" RNA will not be passed on to the next generation, but will only affect the protein of ontology expression.

Central rule: DNA is transcribed into RNA, and then RNA is translated into protein.

Octopus's genes are very unique, and similar genes are rarely found in other organisms (you know, even humans and fruit flies have 6 1% of the same pathogenic genes), which makes it particularly like an "alien creature".

Octopus has almost as much DNA as humans, but it has more genes encoding protein-25,000 in humans and 33,000 in octopus. Most of these genes are related to the growth and development of nerve cells, and scientists speculate that this is closely related to their "intelligent" wrists and feet.

In addition, octopus has a surprising "special function", which is to modify its gene expression product-protein on a large scale through RNA editing. That is to say, after DNA is transcribed into RNA, octopus can modify the RNA, thus changing the protein of expression, and then changing the cell function. In humans, only 3% of the RNA transcribed by genes can be modified, and most of them occur in non-protein-expressed genes, which will not affect protein.

Octopus's modification of protein's function can make itself more adaptable to the environment. For example, octopus living in the Arctic Ocean has produced more cold-resistant characteristics through RNA editing. If this happens to humans, it may be "Superman".

Interestingly, most of these editing sites appear in protein, which is related to the function of nerve cell connection, so scientists speculate that this may also be the reason why octopus has superior intelligence among invertebrates.

It is precisely because of Zhuo Qun's "IQ", strange looks, special habits-of course, the most important thing is the "weird" gene that scientists nicknamed him "alien visitor". Many characters in science fiction works are also based on octopus, such as Captain Davey Jones in Pirates of the Caribbean and Xiaoyou in Parasitic Beasts.