Animal hearing ranges differ generally according to size. Larger mammals such as horses, cows and elephants are typically able to hear lower frequencies than smaller mammals like humans, and dogs, which hear higher frequencies than humans. But exceptions exist: Bats and whales have wide hearing ranges. Mice have relatively broad frequency ranges, for instance, but some sounds audible to us are inaudible to them.
A Relatively Large Range
The mouse is capable of hearing sound frequencies between 1,000 and 91,000 Hertz. That's a relatively broad, range; but in order to hear all frequencies within the range, the volume must be sufficient and unobstructed. Very quiet sounds emitted from distance or from behind baffling material like walls or woodland, may not be audible to a mouse, despite that the sound frequency is within the mouse's range of detection.
Compared With Yours
Humans have a much narrower hearing range than mice. Our range starts lower than that of mice, at 64 Hertz, it ends significantly lower too, at 23,000, meaning mice can hear sounds on a frequency spectrum 68,000 Hertz higher than we can. The difference in mammalian hearing capability is linked to head size. Mammals with smaller heads are better at detecting higher-frequency sounds. This comparison is not true of all animals. For example, goldfish have smaller heads than mice but can hear much lower frequencies.
Communication You Can't Hear
Mice use sound to communicate. Much of their communication occurs on a frequency range inaudible to human ears. This makes detection of mice by sound problematic for humans. The mouse's squeaks may sound extremely high-pitched to you, but the fact that these sounds are audible to your ears means they're some of the lowest-frequency sounds a mouse can produce and hear.
Like humans, the capacity for hearing degrades with age in mice. Mouse hearing is most sensitive around 30 days of age. After 50 days of age, mouse hearing sensitivity, both in terms of the volumes required for audibility and the frequencies detected, begins to degrade. By 20 months of age, mice display significantly less sensitivity to sound.
- John Foxx/Stockbyte/Getty Images