Growth and Patterning of the Face and Branchial Arches

Abstract

The craniofacial structures are mainly designed for feeding and protecting the brain together with the sense organs, the eye, nose, and ear. How these complex structures arose is a fundamental question for both evolutionary and developmental biologists. One possibility is that the lower jaw, for example, evolved by modification of the gill bearing arches found in jawless vertebrates (reviewed by Kimmel et al. 2001; Kurantani et al. 2001). Following the formation of the jaw apparatus such as that found in amphibians, there have been further adaptations in mammals such as the acquisition of the distinct temporomandibular joint, which has allowed full development of the mammalian auditory system.