I enjoy learning about animals and hope you do too. The important take-away I want to point out is that because animals have different abilities from us, in this case a range of hearing, we can learn why they react to things differently than we do. Rather than getting frustrated with a dog for barking at something you cannot hear or if they get scared about a loud noise just know that they have much more sensitive hearing than you do. And, while you may want to teach them to not bark or be afraid please understand that they are technically not barking at or reacting to ‘nothing’. They are simply barking at something you do not hear or personally feel is a threat.
This post will cover:
How animals hear with or without ears
Hearing range for different species
Differences and similarities between cats, dogs, and other common pets
How Animals Use Their Ears and other Adaptions
There is a wide range of ear shapes and ability. Dogs and cats are well known for their amazing sensitivity to sounds. But many other species have excellent hearing or have developed other ways to sense either their prey and/or a predator nearby.
Some animals use specialized organs or sensors to detect their surroundings and specifically food or danger. Pythons and boa constrictors use what is called a pit organ that detects infrared radiation from their potential prey. Spiders use body hairs called trichobothria on their legs to detect vibrations and movement. The platypus has special receptors in it’s bill that can detect electrical impulses in the water.
For more information about other animals check out this article https://www.bioexplorer.net/animals-with-best-sensors.html/
Bats famously use echolocation and have excellent hearing. But, they first must emit sounds from thier mouth or nose and then detect the echo of that sound bouncing back with their ears. Interestingly, moths have developed ways to either fool or hide from the bats. But, that is going down a whole extra rabbit hole so I digress.
Dogs, Cats, and Humans
Humans have decent hearing but still have limitations.
The outer ear or ‘pinna’ (also called an ‘auricle’ for humans) is what we can see and is a distinctive size and shape for different species and pet breeds.
One of the functions of this very visible part of the ear is to funnel and amplify sound for the internal parts of the ear. The appearance or size of pinnae does not necessarily dictate the animal’s ability to hear. For example an elephant (huge pinnae) can hear between 16 – 12, 000 Hz and an owl (no pinnae) can hear between 200 – 12, 000 Hz.
Interesting fact: Some species of owls appear to have ‘ears’ but they are actually just feathers!
Dogs and cats both have distinctive pinnae and many more ear muscles than humans. These muscles are used to manipulate their ears and detect sounds from quite a distance. Humans have 6 muscles in each ear while dogs have 18 and cats have a whopping 32!
I did try to find out how many ear muscles mice, elephants, and rabbits have but after skimming very technical articles (apparently there is a lot of research about the middle or inner ear in mice) I gave up. So if any of you know those facts please let us know in the comments below!
Both dogs and cats can move their ears independently, up to 180 degrees, to help focus in on a sound they are curious about. They also have a much greater sensitivity to higher frequency sound.
Interesting fact: The little fold of skin at the base of a dog’s and cat’s pinnae is technically called a ‘cutaneous marginal pouch’ and more commonly known as ‘Henry’s pocket’. The exact function of this skin fold is unknown but some theorize that it may enhance sound or aid the movement of the pinnae.
The pinnae are not just for hearing of course and are used for heat regulation, expressing emotions and communication, as well as general adorableness.
Humans hearing range is 64 -23,000 Hz and are most sensitive to sounds around 3,000 Hz which is the typical pitch of human voices.
Cats hearing range is 45 – 64,000 Hz and are most sensitive to sounds around 8,000 Hz.
Dogs hearing range is 67-45,000 Hz and may find sounds sounds greater than 25,000 Hz very scary or uncomfortable.
So cats definitely can hear a wider range of sounds than even a dog. Both cats and dogs hear much better in the higher range than humans. And, they can also hear from a farther distance.
Note: Hertz is just a standard measurement used to indicate the frequeny of a sound wave so the higher the number the higher the frequency or the greater range of sound an animal can hear.
Interesting fact: Beluga whales and porpoises have no external pinnae but can hear up to 123,000 Hz and 150,000 Hz respectively.
I thought it was really interesting that a goldfish (20-3,000 Hz) has a greater range of hearing than a chicken (125-2,000 Hz). Cows have a greater range than humans, 23-35,000 Hz vs 64-23,000 Hz! Canaries and cockatiels have a range from 250-8,000 Hz. Rabbits can hear up to 42,000 Hz, rats up to 76,000 Hz, and mice up to 91,000 Hz. Mice and beluga whales cannot hear below 1,000 Hz. And ferrets can hear as low as an elephant, 16 Hz (the lowest I saw listed).
For more information about hearing ranges in a variety of animals check out https://www.lsu.edu/deafness/HearingRange.html
Animals develop many different behaviours and physical adaptations to help protect them from predators and other environmental pressures. So it’s not all about how well they can hear. But it is really interesting to see the comparison between these species and learn more about how they use their abilities.
Next time your dog barks ask them what the neighbour down the road is up to, maybe it is something interesting. They probably will not answer you in english though. I will discuss body language more in future posts. But, for now if you’re not sure check out one of my favourite celebrity dogs and the english translations of their vocalizations. The translations are definitely funny and may be close enough!
Resources for further reading:
Originally published February 14, 2021