Head and Neck Muscle Evolution from Sarcopterygian Fishes to Tetrapods, with a Special Focus on Mammals

This chapter focuses on sarcopterygians (the group that includes extant actinistians, dipnoans, and tetrapods) and explores how the head and neck muscles evolved during the transitions from sarcopterygian fishes to nonmammalian tetrapods and then to mammals, including modern humans. It summarizes the best-supported hypotheses of homology for the head and neck muscles of the sarcopterygian taxa. The chapter describes the development and muscular variations/abnormalities of own species, Homo sapiens. It provides the multidisciplinary data needed for an integrative synthesis of the anatomical macroevolution of the mammalian head and for future functional and developmental comparative studies. A weakness of many studies of the adult cephalic muscles of mammals is the lack of comparisons between monotremes, marsupials, and placentals, or between these groups and other tetrapods, which makes it difficult to understand the origin and evolutionary history of the mammalian head muscles.