A vertebrate is an animal that has a skeleton with a spine and skull , and whose central nervous system is made up of the spinal cord and the brain . The term comes from the Latin vertebratus .
Vertebrates ( Vertebrata ) belong to the phylum of chordates , those animals that are characterized by the presence of a dorsal chord or notochord . Specialists estimate that there are between 50,000 and 61,000 species of chordates today.
Vertebrate animals have had the ability to adapt to different environments. Some have evolved in the sea and then moved to the terrestrial environment.
The body of vertebrates
Generally, the body of vertebrates can be divided into three regions: head , trunk (which, in turn, is subdivided into thorax and abdomen ), and tail . On the trunk, the limbs protrude, which are paired in all vertebrates with the exception of lampreys .
Aquatic vertebrates have a gill respiratory system , while, in the case of terrestrials, the respiratory system is pulmonary .
Another important characteristic of vertebrates is the integument , which is usually the most extensive organic system of the animal (it covers it completely and protects it from the environment). The integument is made up of three layers: epidermis , dermis and hypodermis .
The skin of vertebrates gives rise to epidermal formations (phane, sebaceous , sweat and/or mammary glands ) and dermal formations (such as fish scales or the bone plates of turtle shells, for example).
On the other hand, it should be noted that the endocrine system of vertebrates is controlled by the hypothalamus and the pituitary gland .
The pain
One of the most recurring debates in recent decades is about pain in animals . Many individuals object that they do not have the capacity to feel pain, like humans, and that is why they have no interest in avoiding it; This is how they justify prehistoric customs such as fighting and all types of martyrdom to which they condemn other species.
It is important to point out that pain is fundamental for the survival of every individual since, through this negative experience, they must become aware of the need to react against what threatens them and seek their survival. The individual's reactions to that pain can be a movement of flight or attack .
Pain is not always something physical, sometimes it is emotional : the death of a loved one, for example, causes an individual a feeling of deep sadness that leads him to make a decision regarding his own existence. If an individual did not have the ability to feel pain, then they would not be able to take care of their physical or emotional integrity and would harm themselves.
On the other hand, if what is stated by science is taken into account, all individuals with a central nervous system have the capacity to feel pain , it is understood that humans are not the only animals that suffer and respond to pain stimuli, but all living beings that have a central nervous system . Since vertebrates are among this large group of individuals that have a nervous system with these characteristics, we can conclude by saying that all those who are part of this last group are endowed with this ability to feel pain and react to it .
All this leads us to say that no fighting bull is exempt from this notion of pain, that during the bullfights they are aware that death is approaching and they are extremely scared and look for the bullfighter because they are begging for help. What do you receive in return? More pain, incomprehension and uncontrolled screaming and howling. Can we continue to justify such cruelty?