Evolution and development of the cartilaginous skull: From a lancelet towards a human face

Abstract

Chrondrocranium, the cartilaginous skull, is one of the major innovations that underlie evolution of the vertebrate head. Control of the induction and shaping of the cartilage is a key for the formation of the facial bones and largely defines facial shape. The appearance of cartilage in the head enabled many new functions such as protection of central nervous system and sensory structures, support of the feeding apparatus and formation of muscle attachment points ensuring faster and coordinated jaw movements. Here we review the evolution of cartilage in the cranial region and discuss shaping of the chondrocranium in different groups of vertebrates.

Keywords: Cartilage; Cartilage function in the head; Cartilage in chordates; Chondrocranium; Cranial evolution; Embryonic development; Evolution; Face; Facial shape; Invertebrate cartilage; Protection of central nervous system; Support of feeding apparatus.