Flight of the Seabird

Birds come in all shapes and sizes. They can be found in the air, in trees and bushes, on the ground, and even in the water. Evolutionary adaptations within the class Aves (birds) account for the diversity, including the middle- and inner-ear structures.

In a recent study, ornithologists compared 127 species of bird ears to catalog morphological traits, paying particular attention to the middle-ear structures in birds who dive and hunt for their prey underwater (Zeyl, et al., 2022). 

As audiologists, we know that the middle ear serves as an impedance matcher between the atmospheric pressure and the inner ear. However, in birds who dive to great depths, modifications of this system are necessary to hear their prey and also protect themselves from barotrauma during their aquatic missions.

For a greater understanding of underwater acoustics and how it relates to middle-ear structure diversity, check out the link in the reference below.  

Reference

Zeyl JN, Snelling EP, Connan M, Basille M, Clay TA, Joo R, et al. (2022) Aquatic birds have middle ears adapted to amphibious lifestyles. Nature News. Electronically published March 28.