Many people confuse octopus and squid, which are shellfish. This is due to the fact that both representatives of invertebrates have tentacles and live in the ocean. However, by some, and significant, features, they can be distinguished.
What is the difference between octopus and squid? In fact, they are in many ways similar, but there are differences between them and even significant ones. Both marine inhabitants prefer to be at depth for most of their life, but cases of their appearance on the surface are known. More details about how they differ will be described in the proposed article.
Definitions
Squid is a mollusk with an elongated body shape with many limbs, belonging to the class of cephalopods.
Octopus is a mollusk (a member of the class of cephalopods) with a body that has eight tentacles.
Let's leave the terminology. After all, below are some of the most significant differences between squid and octopus (the photos in the article demonstrate the difference).
Color
Octopus can change the color of its body. This is due to the fact that it is quite difficult to hide from enemies among the environment of the seabed, and the need to change one color tothe other occurs frequently in this animal. Cells that have different pigments in the skin of this unique representative of the depths are responsible for this process.
In order for the squid to remain not very noticeable in the sea, it is enough to have a darker shade of the upper body and a light one of the lower. However, some squid can glow (have bioluminescence). This happens thanks to special organs that octopuses do not have.
Comparison of body shapes
Squid and octopus differ not only in color, but also in their appearance. In the first, the body has an elongated shape, thanks to which it can “cut through” huge underwater expanses, making sharp forward movements with its “tail”. Well-developed fins also contribute to rapid movement, both under water and on its surface.
In the squid, the head is slightly separated from the body, and in the octopus, these two parts of the body are almost merged together. In addition, octopuses, which live mainly on the bottom of the sea and prefer to crawl to a greater extent, are shapeless creatures. There are even jelly-like jellyfish among them.
Squid and octopus rudiments
The difference lies in the fact that the first one has a well-defined body shape. It is due to the reduced hard shell contained in it, which once had an external location.
And octopuses have a vestige of a shell, but itso insignificant that it cannot support the shape of the animal's body. There is a positive point in this - the absence of hard tissues makes it possible for the octopus to move along very narrow cracks or find itself in a small limited space. In addition, during the hunt, this shapeless creature perfectly disguises itself, flattening its body at the bottom of the sea.
Tentacle difference
The difference between squid and octopus is also in the number of their limbs. The second one is a little behind. The octopus has eight of them, and the squid, in addition, has two more tentacles, elongated in the process of evolution. Their purpose is to capture food.
There is also a difference in the suckers present on the tentacles of both representatives of molluscs. The squid is characterized by coarser tentacles with jagged sharp edges. In addition, the larger varieties have suckers equipped with claws that can pierce the victim.
The difference between squid and octopus can also be seen in the process of their hunting for prey. They work not only with tentacles, but also with their beak. The octopus is more powerful. With it, the animal strikes the prey and injects poison into the resulting wound.
Lifestyle
The behavior of animals also has some differences. What is the difference? They consist in the fact that many squids during the hunt prefer to act in packs, making hunting attacks together.
Octopuses in this regard are more imposing, and they are characterized by actions alone. They sneak up to throwing distance unnoticed and attack prey from their ambush. As you can see, the differencesoctopus and squid are also noticeable in their behavior.
A little about sizes
It is safe to say that today the largest representative of cephalopods discovered by man is the squid. The length of his body, along with tentacles, can reach up to 17 meters, but scientists say that this is not the limit. Of course, in the depths of the ocean you can also find octopuses that are quite large and imposing, but when compared with giant squids, they do not look that big.
Today you can get to know these amazing representatives of the deep sea in the aquarium. By visiting it and seeing these amazing marine animals, you can understand not only the difference between them, but also appreciate their peculiar beauty.
In conclusion, one more feature of one of these animals can be noted. Squid has another feature - it has the ability to regenerate: if you lose some part of the body, after a while it can be restored again.
