TYPES OF SKULL IN HUMANS - ANATOMY AND PHYSIOLOGY - 2025

The types of skulls of the human being can be classified according to evolution, according to race and finally, according to genetic formation. The skull is a bony structure that forms the head in most vertebrates, acting as a “box” for vital organs such as the brain, or sensory organs such as the eyes and tongue. The elements that make up the central nervous system are integrated within the cranial structure.

The human skull is divided into two large parts: the neurocranium, which corresponds to the upper and posterior part and houses most of the cerebral and nervous components; and the viscerocranium (or facial skeleton), which contains mainly the facial bones, with the mandible being its largest bone piece.

The structure of the human skull, as well as in other vertebrates, can be considered an adaptive part of a cephalization process, due to the accumulation of tissue and sensory receptors that results in a central nervous system and in crucial organs.

The structure of the human skull is divided by bones that, with the exception of the jaw, are joined by bone sutures; cavities, such as those responsible for housing the brain, eyes and nostrils; and foramina, as small openings in the skull that allow the passage of blood (veins, arteries) and cells from the bone level to the muscular or facial level.

The differences between the skull of men and women have been the subject of quite extensive discussions, with historical, anthropological and cultural aspects that have given continuity to the physical superiority of men over women.

However, it has been concluded that, although the skull of men may present a greater volume and robustness, the female skull has a greater thickness in its neurocranial part, providing greater protection to the brain.

Types of skull according to evolution

The human term, categorized as "homo", saw its first biological manifestation in Homo erectus, approximately 750,000 years ago.

The physiognomy of this specimen set a precedent to discern evolution until the arrival of Homo sapiens sapiens.

Herto man, discovered in Africa, estimated to have inhabited 160,000 years ago, is an example of the evolutionary transition between erectus and sapiens.

The skull had characteristics closer to Homo erectus due to its robustness, such as: large eye sockets, large and elongated teeth, wide cheekbones, and a heightless forehead, sloping towards the back of the head.

This type of skull has been attributed an average brain matter capacity of 1450cc, close to that of Neanderthals and much higher than the capacity of modern Homo sapiens.

Homo sapiens neanderthalensis has been considered the closest relative of Homo sapiens sapiens, however its territorial and temporal presence has been disputed, since it has been stated that both could live together in the same period.

The Neanderthal skull has primitive features such as large teeth, an elongated protrusion at the back, a flat forehead, and fairly pronounced cheekbones.

It has been estimated that the capacity of brain matter that accommodated the Neanderthal skull was on average the same as that of erectus, and much greater than that of modern Homo sapiens.

Modern Homo sapiens has the most delicate cranial characteristics of all its relatives or ancestors.

The modern sapiens skull has more rounded edges and contours, a higher forehead, mandibular features and a sharper and more pointed jaw, as well as smaller and closer facial elements.

Types of skull according to race

The modern Homo sapiens skull has developed different qualities depending on its race and its geographical location on the planet. The European, African and Asian skull are the main dividers.

European skull

Also referred to as the Caucasian, it has a characteristic shape that is more elongated and narrow than others.

They have less pronounced cheekbones and a longer jaw; the eye sockets are semi-rectangular in shape and slightly sloping; it has a fairly integrated set of teeth and small teeth; the nostrils are triangular in shape.

African skull

Referred to as Negroid, they have a more elongated and sloping formation from the jaw to the forehead. This facial tilt develops a certain protrusion or mandibular relief.

The eye sockets are rectangular and wide, farther apart than other breeds. It has a much wider but less pronounced nasal bridge than its European or Asian peers.

Asian skull

Also referred to as Mongoloid, it is much shorter in length but with greater breadth.

The cheekbones are usually wider and extend to the sides of the skull, with a slight inclination; the eye sockets are small and round and, unlike the European skull, they are not inclined.

The nostrils present a certain width in their lower part and a pronounced nasal bridge similar to the European one.

Types of skull according to genetic formation

Craniology and medical studies have made it possible to classify congenital cranial formations in humans, creating a kind of cranial index (maximum width with respect to maximum length).

They are considered as variables that arise from head development. These categories are established mainly from the diametrical qualities that the skull presents.

Dolichocephaly (or scaphocephaly)

A dolichocephalic person presents a skull whose parietal bones present a premature fusion, generating an elongated and narrow cranial formation. This condition prevents lateral growth of the skull.

Brachycephaly

It consists of the premature fusion of the coronal suture, which prevents the longitudinal growth of the skull.

It can also cause flattening at the back and top, resulting in a short, wide skull. It usually occurs during the first months of life.

Mesocephaly

It is the shape and measurements of the skull that is located between dolichocephaly and brachycephaly. It is considered as the average or normal cranial diameter. The skull does not have long or short extensions, or conspicuous widths.

The process of premature fusion of fibrous sutures that shape the skull during the growth stage, unevenly separating the bones, is called craniosynostosis.

This phenomenon can generate enough space for brain accommodation, sacrificing facial symmetry.

References

1. Fuerza, RD (2008). Erectus Walks Amongst Us. New York: Spooner Press.
2. Lieberman, DE (1995). Testing Hypotheses About Recent Human Evolution From Skulls: Integrating Morphology, Function, Development, and Phylogeny. Current Anthropology.
3. Martínez-Abadías, N., Esparza, M., Sjøvold, T., González-José, R., Santos, M., Hernández, M., & Klingenberg, CP (2012). Pervasive Genetic Integration Directs the Evolution of Human Skull Shape. Evolution, 1010-1023.
4. Pelayo, F. (2010). The Configuration of Human Paleontology and Darwin's The Descent of Man. Nova Epoca, 87-100.
5. Shreeve, J. (2010). The evolutionary path. National Geographic, 2-35.
6. Smithsonian National Museum of Natural History. (2017). Human Evolution Evidence. Retrieved from What does it mean to be human ?: humanorigins.si.edu.
7. The Editors of Encyclopædia Britannica. (3 of 12 of 2008). Cephalization. Retrieved from Encyclopædia Britannica: britannica.com.