The evolution of the mammalian pharynx

Data derived from studies of comparative anatomy, development, neuroanatomy, behaviour and the reconstruction of fossils are combined to evaluate the evolution of the oral‐pharyngeal region in mammals. An important event in the evolution of the mammalian feeding apparatus was the development of a novel neuromuscular apparatus, consisting of a large series of striated muscles. The most important of these muscles are the pharyngeal elevators and constrictors, which appear to be without homologues in other amniotes. In addition to considerable peripheral neural and muscular modifications, the motor nuclei of the brain stem in mammals exhibit significant differences from other amniotes. The morphological features characteristic of mammals are reflected in behavioural differences, most significantly during swallowing and suckling. The neuromuscular changes in the mammalian oral‐pharyngeal apparatus are at least as extensive as those involving the masticatory system, and have importance far beyond the separation of the airway and foodway, the foci of most previous studies. The hypothesis of neuromuscular conservativism in the evolution of the mammalian feeding mechanism is considered and it is concluded that few data exist to support this hypothesis. Copyright © 1992, Wiley Blackwell. All rights reserved

Duke Scholars

Author Kathleen Kovalevski Smith Biology