Vertebrate animals are all those that have a skull, tail, and a spine or spine that divides their body into two equal parts. Its skeleton is internal and can be bony or cartilaginous.
About 60 thousand species belong to the group of vertebrates, including extinct species.
As for its taxonomic category, this type of animal belongs to the subfile Vertebrata, one of the three groups of the Chordata edge or ropes, a division of the animal kingdom in which those species that had a dorsal cord, a neural tube in position are located dorsal, gills and tail at some stage of its embryonic process.
Origin of vertebrate animals
It is estimated that vertebrates appeared at the beginning of the Cambrian period, about 530 million years ago, specifically during a period called “Cambrian explosion”, characterized by the sudden appearance of complex multicellular organisms.
The findings of the oldest vertebrates, such as the Haikouitchys and the Myllokunmngia (two organisms with skulls, very similar to fish), suggest that it is a group of animals that originated in freshwater, but then adapted to others environments, which allowed them to have a presence not only in the water, but in the land and air.
Types of vertebrate animals
Vertebrate animals are classified into 4 large groups.
Osteichthyes (osteictios)
To this group belong all fish that have internal bone skeleton, that is, made of bones. Although they may have cartilaginous structures, these constitute a minimal part. They usually have a terminal mouth with articulated dermal bones, from where the teeth come out. Once they lose their teeth, they cannot replace them.
The giant grouper and the scorpion fish are two examples of osteotic fish.
Giant grouper, a type of osteictio
Chondricthyes (condrictios)
They are vertebrate fish with internal cartilaginous skeleton, for the most part. Your teeth are not fused with the jaw and replace them as they wear out.
Chimeras, rays, blankets and sharks belong to this group.
The shark is the best known condrict vertebrate.
Agnatha (agnatos)
They are all vertebrate fish that lack jaw. They look like an eel, and since they cannot process the food in the same way that fish with jaws are hematophagous (feed on blood) and ghouls (feed on corpses).
Lampreys and mixines are vertebrate agnatos.
A brunette eel, a vertebrate of the agnatha type.
Tetrapoda or animals with four exterminations
To this group belong mammals, birds, reptiles and amphibians.
Mammals
They are characterized by the presence of hair, hands, feet or legs, as well as having a jaw with dental bone and the presence of mammary glands.
The lion, the dolphin, the horse, the dog and the human being are some examples of mammalian vertebrates.
The horse is a mammalian vertebrate.
Birds
They are vertebrate animals characterized by the presence of feathers. They remain on their hind limbs, while the former evolved into wings. However, not all bird species are capable of flying.
The eagle, the parrot, the hummingbird, the hawk and the pelican are some known birds.
The parrot or macaw is an example of a vertebrate in the group of birds
Amphibians
This type of vertebrate animal is characterized by an important muscular development in its extremities, which allows them to move through jumps or swimming.
The toad, salamander and newt are vertebrates of the amphibious group.
Salamander belongs to the category of amphibians within vertebrates.
Reptiles
They have tough skin, covered by keratin scales. Their limbs are very short or non-existent (as in snakes), so they have to move crawling. They are also able to lay eggs in shell.
The turtle, the iguana and the crocodile are some of the best known reptiles.
The sea turtle is a vertebrate within the amphibian group.
Types of vertebrate animals according to their body temperature
In turn, vertebrates are divided into two large groups, depending on their ability to regulate their internal temperature.
Vertebrate animals endotherms
Also known as ‘warm-blooded’ vertebrates, they are those capable of maintaining a constant temperature regardless of external factors. In general, its temperature range is between 34ºC and 38ºC.
Mammals and birds are in this group.
Vertebrate animals ectotherms
Also called “cold-blooded” vertebrates, they are all those animals that can regulate their body temperature based on external temperature.
Reptiles, amphibians and fish belong to this group.
