The middle ear is the chamber containing the tiny bones that link the eardrum to the neuronal structures of the inner ear. Its mechanical performance is a major factor determining hearing range and sensitivity. We know very little about how middle ear anatomy in different mammals may be adaptively specialized for different environments. This interdisciplinary collaborative study combines a bioengineering and theoretical approach with comparative anatomy to derive and test models for middle ear mechanics. Hearing physiology is well known for the domestic cat, but the whole cat family (Felidae) includes a large range of sizes and a wide diversity of habitats. This work compares the anatomy across a range of felids to obtain precisely measured dimensions, mathematical scaling factors for size, and construction of models of acoustical mechanics. Predictions from these models will be tested by non-invasive recordings from diverse representatives, including some rare species only available in zoos. Results will be important not only to auditory biology, but to bioengineering and to evolutionary biology.
