Abstract: Computational, anatomically derived modeling of hearing in mysticetes (baleen whales) can be a valuable technique for estimating hearing ranges when live animal experimental measures are not possible. To date, the authors have produced finite element models (FEMs) for the middle ears of two baleen whales. These models provide an analysis of the middle-ear transfer function that is the basis for estimating best hearing range and auditory thresholds of any mammal. One difficulty in modeling whale hearing is that mechanical and physical tissue properties required for these models have not been measured in many cetaceans, and those that have been measured show significant species differences. Therefore, we undertook a study to examine how varying tissue properties over a wide potential range based on known values of mammalian tissue analogues affect the model output and estimated hearing ranges in the humpback whale (Megaptera novaeangliae). Twenty-one total parametric variations were tested. Model results indicate that eight parameters can have significant impacts on hearing estimates, affecting key hearing characteristics, including peak frequency, auditory bandwidth, low- and high-cutoff frequencies, and response magnitude.
Key Words: humpback whale, Megaptera novaeangliae, cetacean, hearing, model, material properties, mechanics
DOI: https://doi.org/10.1578/AM.45.6.2019.717
Page Numbers: 717-732
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