Introduction
The term vertebrate refers to the spine’s joints. These animals’ spines or backbones are made up of discrete pieces called vertebrae that are connected by movable joints. Vertebrates emerged over 530 million years ago during the Cambrian epoch. From the Polar Regions to the Tropics, this subphylum, or sub-division, contains species. They range in size from the tiniest fish to elephants and blue whales, the world’s biggest mammals. Vertebrates have evolved to life on land, in the air, and in water. They consume plants, invertebrates (animals without backbones), and other invertebrates.
Vertebrate, alternatively termed Craniata, any animal belonging to the subphylum Vertebrata, the phylum Chordata’s dominant subphylum. They are known for having strong backbones, which is how they received their name. Additionally, vertebrates have a muscular system that is generally composed of bilaterally paired masses and a central nerve system that is partially encased inside the backbone.
The subphylum is one of the most well-known animal groupings. Its members are classified as Agnatha, Chondrichthyes, and Osteichthyes (all fishes), Amphibia (amphibians), Reptilia (reptiles), Aves (birds), and Mammalia (mammals) (mammals).
Vertebrate species
The following databases keep (approximately) current listings of vertebrate species:
- Fish
- Amphibians
- Reptiles
- Birds
- Mammals
Natural history
To provide a comprehensive and comparative picture of their life histories, the vertebrates are classified here into four major morphological groups: the cyclostomes (jawless fishes), the chondrichthyes (cartilaginous fishes), the teleostomi (bony fishes), and the tetrapods.
Vertebrates have the following distinguishing characteristics:
- A genuine vertebral column and an internal skeleton with muscle attachment sites for bodily movement are present.
- A muscular heart having two, three, or four chambers on the front side.
- Kidneys are responsible for excretion and osmoregulation.
- Fins or limbs are examples of appendages that are joined together.
- During the embryonic stage, possess the notochord.
- Only vertebrates have a brain as part of their central nervous system.
Vertebrate Classification
Vertebrates are categorised into seven distinct groups according to their morphological and physiological characteristics. They are as follows:
Mammals (Class Mammalia)
This class of creatures is capable of self-regulating their body temperature regardless of the ambient temperature. As a result, mammals, which include humans and platypuses, are referred to as endothermic creatures.
Birds (Class Aves)
Birds are dinosaurs from a biological standpoint (more aptly called avian dinosaurs). Feathers, toothless beaks, and a rapid metabolic rate distinguish this class of creatures. Additionally, members of the class Aves lay eggs with a hard shell.
Example: Parrot
Reptiles (Class Reptilia)
Tetrapods such as snakes, crocodiles, tuataras, and turtles are considered reptiles. Reptiles are characterised by their ectothermic nature. Snakes, on the other hand, are still considered tetrapods.
Example: Lizard
Amphibians (Class Amphibia)
Amphibians are tetrapods that are ectothermic, such as frogs, toads, and salamanders. Amphibians are distinguished from reptiles by their breeding behaviour. The majority of amphibians require a body of water to procreate since their eggs lack a shell. Additionally, they undergo metamorphosis, during which the young develop from completely aquatic larvae (with gills and fins) to terrestrial adults.
Example: Frog
Bony fishes (Class Osteichthyes)
This group of fishes is defined by their skeletons, which are predominantly formed of bone rather than cartilage (such as sharks). Additionally, the class Osteichthyes is the biggest vertebrate class today.
Example: Consider catfish.
Cartilaginous fishes (Class Chondrichthyes)
As implied by the name, this class is defined by a cartilaginous skeleton. Sharks, rays, skates, and sawfish are all members. Certain sharks, such as the colossal Greenland shark, can live for hundreds of years. In 2016, a specimen tagged in 2016 was determined to be at least 273 years old.
Example: Shark
Jawless fishes (Class Agnatha)
These are extremely primitive fishes that have not altered significantly over millions of years based on fossil records. They have a circular, jawless mouth with rows of little sharp teeth that enable them in grasping and eating other fish. The majority of this class’s members are parasites and scavengers.
Example: Cyclotoms
Conclusion
They are known for having backbones, which is how they acquired their moniker. Additionally, vertebrates have a muscular system that is generally composed of bilaterally paired masses and a central nerve system that is partially encased inside the backbone. The subphylum is one of the most well-known animal groupings.