Just as unique as their eyes, a cat’s ears are another marvel of feline adaptation. As with most everything else in cats, they are fine-tuned for hunting. Their ears actually have two functions: hearing and balance, but in this newsletter, we will focus on the hearing aspect.
Anatomically, the most visible portion of a cat’s ear is the external ear (called the pinna.) It is large, upright, and cone-shaped; and it acts to both catch and amplify sound waves. A cat’s ear can amplify sound waves 2 to 3 times for frequencies between 2 and 6 kHz. Thanks to about 30 sets of muscles (by comparison, humans only have 6 sets), a cat can rotate its pinna up to 180 degrees in order to locate and identify the faintest of noises.
Humans and cats have a similar range of hearing on the low end of the Hertz (Hz) scale, with people being most sensitive to sounds of around 3,000 Hz (or 3 kHz–most human voices are near that pitch.) A cat, however, is most sensitive to sounds of around 8,000 Hertz (8 kHz.) They can also hear up to 64 kHz, which is 1.6 octaves above the upper range of human hearing (which is about 20 kHz). They can even hear 1 octave above the range of a dog (which is about 45 kHz) and only slightly less than the range of a porpoise. Cats can also hear sounds at great distances, four to five times farther away than humans.
Additionally, cats can detect the tiniest variances in sound, distinguishing differences as little as one-tenth of a tone. This helps them identify the type and size of the prey producing the noise. A cat up to 3 feet away from a sound’s point of origin can pinpoint its location to within a few inches in a mere 0.06 seconds. This heightened sense of hearing also enables feline mothers to hear any faint squeals of distress from their kittens.
If you want to see how you compare to a cat, here is a little test: Ask someone to stand ten feet away from you while holding a “clicker” type ballpoint pen in each hand. Have the person hold the pens about 10 inches apart, then close your eyes and see whether you can distinguish which hand “clicked.”
Cats, like humans, can experience hearing problems or even total deafness due to disease, infections, ear trauma, or simply old age (thickening of the ear drum.) However, in domestic cats, deafness is most commonly due to a hereditary condition. Interestingly, deafness is often associated with white cats, especially with blue eyes (but not all such white cats.) This is because there are two genes that cause the coat to be white: the dominant white gene and the white spotting gene. The dominant white gene is the gene that can be associated with deafness.
According to one study, about 40% of white cats are deaf in both ears and about 12% are deaf in one ear. Blue-eyed, white cats are more likely to be deaf, with cats having two blue eyes as more likely to be deaf than cats with one blue eye; and both are more likely to be deaf than cats with no blue eyes. Furthermore, cats with one blue eye and deafness in one ear tend to be deaf in the ear on the same side as the blue eye.
We hope that you’ve found this information to be educational. As you can see, cats have exceptional hearing, and even if a cat should experience deafness, they learn to quickly adapt with their other keen senses. We will explore more of those senses in our next newsletter!