Deep-time origin of tympanic hearing in crown reptiles
Mario Bronzati, Felipe Monteleone Vieceli, Vitória Samartin Botezelli, Pedro L. Godoy, Felipe C. Montefeltro, Jann P M Nassif, Juliana Luzete, Douglas C. Ribeiro, Chao Yan, Ingmar Werneburg, Tiana Kohlsdorf
Abstract
We combine developmental information with paleontological data to evaluate the evolution of the tympanic ear in reptiles from two complementary perspectives. Phylogenetically informed ancestral reconstruction analyses of a taxonomically broad sample of early reptiles point to the presence of a tympanic membrane as the ancestral condition of the crown group. Consistently, comparative analyses using embryos of lizards and crocodylians reveal similarities, including the formation of the tympanic membrane within the second pharyngeal arch, which has been previously reported for birds. Therefore, both our developmental and paleontological data suggest a single origin for the tympanic middle ear in the group, challenging the current paradigm of multiple acquisitions of tympanic hearing in living reptiles.