A skull, also called a bone head, is the name given to the set of bones that make up the skeleton of the head, formed by the bones of the face and skull, when it is stripped of flesh and skin. The word, as such, comes from the Latin calvaria, which means ‘skull’.
The bones of the skull fulfill the function of surrounding and protecting the brain and sensory organs of the human being, in addition to containing the chewing apparatus. It is made up of 28 bones, of which the jaw is the only mobile bone.
In this way, the skull is made up of the following bones. In the skull, the frontal, temporal, occipital, parietal, ethmoid, sphenoid bones. On the face, the vomer bones, unguis, lower nasal cornet, upper jaw, lower jaw or jaw, zygomatic or malar, palatine, nasal bones and middle ear bones, with hammer, anvil and stirrup.
The skull is also used as a symbol of death, as a warning sign or as an indication on the label of a toxic substance. Also, the skull has been used by pirates, with two crossbones and on a black background, as a symbol on their flags.
As a literary skull it is called a popular poetic composition of the burlesque or satirical type through which ideas and feelings are expressed in a critical and irreverent tone.
Skulls begin to appear in Mexico in the 19th century. They were verses that portrayed characters from public life as if they were dead. They came to suffer censorship, as they were uncomfortable especially for the powerful. Usually, they were accompanied by a drawing that depicted a naked skull with a European fashion hat, which was known as La Catrina or Calavera Garbancera, and whose conception was the work of illustrator José Guadalupe Posada.