The ear is a complex biomechanical system dedicated to sound perception, even though part of the auditory function is located in the central nervous system. The evolution of a tympanic ear has been a key innovation in solving the impedance problem between air and biological tissues allowing sound to reach the inner ear. The coupling between the two middle ear cavities has an effect on the directionality of the eardrum, which acts as a pressure difference sensor. We aim at identifying and quantifying in detail the tympanum structures related to sound perception. We will use nanotomography as a basis for the construction of a highresolution three-dimensional dataset. Such 3D models and comparisons between data obtained for 20 samples of species varying in their frequency response should enable the understanding of the biomechanical basis of hearing very high frequency sounds.