Some of the animals that do not have bones are the octopus, the crayfish, the sea anemones and the centipede. Animals that lack a backbone or an articulated skeleton are classified as invertebrate animals .
Invertebrate animals represent more than 90% of all species recorded by man.
Several of the invertebrates are often confused with vertebrate animals because they have a cartilage skeleton; but that skeleton, although it provides rigidity to the body, does not classify as bone.
The most relevant invertebrate animals
1- octopus
The octopus is an animal belonging to the group of mollusks. It has a large size, which can vary from 15 centimeters to 3 meters long.
The octopus is an omnivore; that is, it feeds on both animals and plants.
2- Squid
Squid, like octopus, is a marine mollusk. Mollusks are invertebrate animals with a soft body naked or protected by some type of shell.
The squid, also called a smoothie, can measure from 10 centimeters to 18 meters. The latter is the least common and is known as a giant squid.
3- Snail
The snail is a mollusk that has a spiral shell on its dorsal part, which covers it against any threat.
There are land and marine snails. Land snails can measure up to 30 centimeters in diameter, while the largest marine snail measures only half: 15 centimeters.
4- Medusa
Jellyfish are animals over 500 million years old. They have bodies with unique and varied characteristics.
They are animals that can be transparent and translucent, can have different colors and sizes, and are the animals with the highest percentage of life expectancy.
5- Centipede
Centipedes belong to the chilopod class and have different presentations. They can measure from less than one centimeter to around 30 centimeters.
They can be of different colors and some can secrete poison.
6- earthworm
The earthworm has an elongated and reddish body that can measure from a few centimeters to a maximum of 35 centimeters.
The earthworm feeds under the ground at night, and is recognized because its work benefits the development of some plants.
7- crab
There are more than 4,000 species of crabs; these present very varied sizes and colorations.
All species have a very rigid body; however, the crab is an invertebrate because its skeleton consists of pure cartilage.
8- Planaria
This animal can be both marine and land. The planaria has a long, wide and flat body; hence the name.
This animal can have tentacles and a size that varies between one centimeter and 6 centimeters.
9- sea urchins
Also recognized as echinoids, they are balloon-shaped animals that have movable spikes, which may have venom.
These animals come in different sizes, shapes, and colors. Despite being static, some of the species are predators.
10- Sea anemones
Sea anemones are called this way because of their resemblance to the anemone flower. They are marine animals with a cylindrical body and tentacles on top.
Many fish use anemones and their tentacles as pantry and protection.
11- I had
Parasite, also known as tapeworm, which causes various diseases in other animals such as cats, dogs or humans, normally through the stomach or intestines.
12- Mosquito
There is a legend that says that the mosquito has bone. Nothing is further from reality, since its structure is maintained thanks to a very flexible substance that does not allow water to pass through your body.
