Audiograms of three subterranean rodent species (genus ) determined by auditory brainstem responses reveal extremely poor high-frequency hearing.

Life underground has shaped the auditory sense of subterranean mammals, shifting their hearing range to low frequencies. Mole-rats of the genus have, however, been suggested to hear at frequencies up to 18.5 kHz, unusually high for a subterranean rodent. We present audiograms of three mole-rat species, , and the giant mole-rat , based on evoked auditory brainstem potentials. All species showed low sensitivity and restricted hearing ranges at 60 dB SPL extending from 125 Hz to 4 kHz (5 octaves) with most-sensitive hearing between 0.8 kHz and 1.4 kHz. The high-frequency cut-offs are the lowest found in mammals to date. In contrast to predictions from middle ear morphology, did not show higher sensitivity than in the low-frequency range. These data suggest that the hearing range of mole-rats is highly restricted to low frequencies and similar to that of other subterranean mammals.