The Water-to-Land Transition: Evolution of the Tetrapod Basilar Papilla, Middle Ear, and Auditory Nuclei

Abstract

The evolution of the auditory system of tetrapods has been the topic of numerous investigations on the middle ear (e.g., Reichert 1837; Gaupp 1898, 1913; de Burlet 1934; Thomson 1966; Henson 1974; Lombard and Bolt 1988), the inner ear (e.g., Retzius 1881, 1884; de Burlet 1934; Werner 1960; Baird 1974; Lewis, Leverenz, and Bialek 1985), and the auditory pathways in the central nervous system (e.g., Larsell 1934; Ariens-Kappers, Huber, and Crosby 1936; Northcutt 1980). The consensus reached by many of these studies was that the water-to-land transition apparently coincided with the coevolution of a tympanic middle ear, a basilar papilla, and a periotic labyrinth in the inner ear, as well as neural pathways devoted to the processing of airborn sound in tetrapods (Fig. 18.1).