Comparative cat studies: Are tigers auditory specialists?

Abstract

Although representatives of the 41 extant cat species inhabit nearly every biome on the planet and may have faced a highly diverse set of selection pressures during their evolution, relatively little effort has been made to compare commonly measured features of peripheral auditory function among species representing the family. Given their extensive geographic range, it is reasonable to suggest that auditory system adaptations may have occurred, leading to functional specialization in a subset of species. In that light, frequency-threshold curves and response latency-level and latency-frequency relationships will be compared in cats of widely varying body mass inhabiting a variety of habitats. The body mass of felids spans a range of more than two orders of magnitude, with small cats like the desert sandcat, Felis margarita, weighing as little as 2 kg and the Amur tiger, Panthera tigris altaica, weighing as much as 300 kg. While most cats studied thus far appear to satisfy the conditions necessary to be labeled auditory generalists, the tiger, and perhaps members of the Panthera genus generally, may be exceptions. We will consider the possibility that big cats are auditory generalists with regard to acoustic sensitivity, but exhibit a peripheral specialization affecting low-frequency neural latencies. [Funding provided by NSF Grant No. 0823417].