Structure of Skull: Splanchnocranium, Chondrocranium, and Dermatocranium

Skull Structure and Terminology

• The contribution that forms most of the outer casing of the skull in later vertebrates is known as the dermatocranium.
• The chondrocranium is the part of the skull composed of endochondral bone, cartilage, or a combination of both.
• Some morphologists use the term chondrocranium as an equivalent for the cartilaginous skull.

Braincase and Skull Components

• The neurocranium encompasses the fused cranial components that surround and encase the brain, providing structural protection.
• The most ancient part of the skull, which originated to support pharyngeal slits in protochordates, is referred to as the olfactory capsule.
• In various species, the braincase can be made up of structures such as cartilage, endochondral bones, and dermal bones.

Expansions of Skull Terminology

• Some morphologists expand the term neurocranium to include additional structures such as facial bones and other components involved in cranial development.
• Other scholars consider the neurocranium strictly as the portion that directly encases the brain, without considering the surrounding components.

Learn about the three distinct parts of the vertebrate skull - the splanchnocranium, chondrocranium, and dermatocranium. Understand their origins and functions in supporting different aspects of the skull.