At the behest of the Zoology, the vertebrates, are animals that have a skeleton with spinal column, skull and central nervous system composed of spinal cord and brain.
The vertebrates or vertebrata are part of the edge of the chordates, which are those animals that are distinguished by the presence of a dorsal cord or notochord. Approximately, it is estimated that there are between 50 and 61 thousand species of chordates, currently.
The vertebrate animal has had the ability to adapt to the different means that life proposes in this world, there are even many that have evolved in the sea and then went to the terrestrial environment without problems.
The body of vertebrates is divided into three zones: head, trunk (The extremities stand out, which are pairs except for lampreys), which in turn is subdivided into thorax and abdomen and line.
It should be noted that in the case of aquatic vertebrates they have a branchial respiratory system, while terrestrial vertebrates have a pulmonary respiratory system.
Another salient feature of vertebrates is the integument, which normally stands as the most extensive organic system of the animal, covering it completely and protecting it from the environment; the integument is made up of three layers: epidermis, dermis and hypodermis.
On the other hand, the skin of vertebrates generates epidermal formations, such as: sebaceous, apricot, mammary or sweat glands, and dermal formations, such as: fish scales, the bony plates of turtle shells, among others .
Meanwhile, the endocrine system of this type of animal is controlled by the hypothalamus and pituitary.
The reproduction of vertebrates is sexual, except in some fish that suffer from hermaphroditism; mammals have a greater complexity, since in them the embryos are gestated inside the mother receiving food through the placenta.
Its origin dates back to the Cambrian explosion, at the beginning of the period Paleozoic.
Another recurring use of the word vertebrate allows to refer to that divided, structured.
