Dogs can’t hear all sounds at four times the distance humans can. They can probably hear some sounds at an even greater distance factor than that, compared to humans. But there are other sounds humans and dogs likely hear at about the same distance, and even some that humans can hear at a greater distance than dogs. We know these things because the hearing sensitivity of both humans and dogs has been measured with controlled tests. The data, broken down by frequency and sound intensity, is reported on charts called audiograms. We can use audiograms of humans and dogs to compare our hearing abilities.
“From how far away can you hear this?” is not the correct metric for measuring or comparing hearing.
So where did this common claim about four times the distance come from? You can open just about any popular article about dog hearing and you will see it. It is presented to support the idea that dogs’ hearing is much better than ours, which in many ways is true. But in my experience, there is never a reference for the specific claim.
We can’t make a general rule that compares the hearing of dogs and humans. And there is another problem. Decibels are a logarithmic scale, not linear. So if a sound is four times farther away, this doesn’t mean it is only one-fourth as loud. This counterintuitive relationship between distance and amplitude doesn’t provide evidence about the truth of the claim, one way or another. But it sure removes some of the “wow” factor. It doesn’t have the same kick if you say, “Dogs can hear sounds at 12 decibels lower than humans can!” That’s the decrease in decibels if you quadruple the distance. If we want to check out the “four times the distance” claim, we can compare the audiograms of dogs and humans to see if there is a difference of 12 decibels or more at some frequencies.
Tracking Down the Claim
When I try to find the source of any claim, my first three tools are date-limited internet searches, journal article searches, and book searches.
Internet and journal searches on this question led me back to 2008. The claim appears near the bottom of this article about the domestic dog, for instance, and in plenty others since then. There may be earlier ones online; I stopped looking after I struck gold during a book search. But all the instances of this claim I saw online had one thing in common: there was never a reference for it.
It was Stanley Coren’s book, How Dogs Think, that lead me to the source. He wrote:
I have often read that a dog’s hearing is four times more acute than ours, which is not strictly true. This statement comes from an informal experiment conducted by P. W. B. Joslin, whose research involved monitoring the activities of timber wolves in Algonquin Park.
Coren, 2004, p. 37
The Joslin article was easy to find. It’s a fascinating and often cited study of wolf howling. (The PDF is downloadable from the URL.) And here’s the pertinent quote:
The howling of wolves can be heard usually at distances in excess of one mile and on rare occasions as far as four miles… For example, at distances of four miles, when the howling of the whole group of captive wolves at the Wildlife Research Station was barely discernible to me and to my assistants, the wolves responded to my howls which were unquestionably weaker in intensity.
Joslin, 1967, p. 288
Really, dog world? We’ve done it again? The statement is about wolves, not dogs. And it doesn’t even say “four times as far”! It says that he and his colleagues could barely hear the wolf howls at a distance of four miles, but the wolves could hear his quieter howls back at that same distance. This is a fascinating early observation about wolves and their hearing. It says nothing about the comparative hearing capabilities of dogs and humans. It’s just another thing that tumbled into dog canon and stuck.
Audiograms
We have data comparing the hearing capabilities of dogs and humans. Here is how hearing is actually compared.
There are at least three ways aspects of dogs’ hearing can be tested.
- Operant conditioning. Dogs are taught to perform a behavior when they hear a tone (Guérineau et al, 2024). This is similar to the pure-tone test for humans, where we wear headphones and signal whenever we hear a sound.
- Respondent conditioning. Dogs learn that a certain tone predicts food, so they begin to drool when they hear the tone. Pitch discrimination has been taught this way (Dworkin, 1935).
- The Auditory Brainstem Response (ABR) or Brainstem Auditory Evoked Response (BAER) test. Dogs are given a non-invasive test where electrodes are attached to their heads and tones are played. The test measures brain activity in response to the tones (Scheifele & Clark, 2012).
Note that moving around and measuring the distance at which dogs can hear a sound from a source is not one of these methods.
Hearing is tested at different frequencies and amplitudes because hearing sensitivity for any species varies by both of these factors. When you use one of the above tests (for a human this would be #1 or #3), the results of the responses are compiled into a graph called an audiogram.
I made a fake audiogram, basing it roughly on actual data. I don’t have the rights to actual audiogram images or the data tables, so I created a graph with roughly the right plots on it. If you want to see a real one, check out the audiogram comparing the hearing of five dogs in this good article about animals’ hearing.
Here is my fake one so you can see a crude comparison of human and dog hearing.
In audiograms, the lower numbers on the y axis show more sensitive hearing, because they represent the softest decibel levels the individual can hear. So audiograms look kind of upside down to us. The most sensitive hearing is at the bottom of the “bowl,” and both species hear less well at the edges of our ranges.
In the low frequencies on the left of the graph, from 60 to about 200 Hz, we see that human hearing is more sensitive. In the higher frequencies on the right, starting at about 8 kHz, we see that the dog’s hearing is far more sensitive than ours. If you compare the values at 20K there is a difference of more than 60 dB. In that area, dogs may be able to hear something at more than a hundred times the distance we can (under the same conditions). By the way, the distance doesn’t have to be huge and measured in miles. We could be talking about feet or meters.
One more oddity about my kludged graph. It’s neither linear nor does it follow all of the modern conventions of a logarithmic scale. But it’s more of a logarithmic graph in that the numbers on the x axis are not the same value apart. This is important to note because the last four values cover a vastly bigger range than the first four. For example, 8,000–30,000 covers the same horizontal distance on the graph as 6–250. So what the graph doesn’t let us visualize well is how vast the frequency range is where dogs’ hearing is more sensitive. If it were a linear graph, continuing the same horizontal spacing for every 40 Hz that we see between the first two values, it would be more than 60 feet long. And dogs’ hearing would be more sensitive than ours for more than 40 feet of it.
Why “How Far Away Can You Hear This?” Is Not a Good Measure of Hearing
How far a sound propagates (travels) depends on at least four variables:
- the amplitude of the sound (how loud it is)
- the frequency of the sound (how high or low the pitch is)
- the weather (whether it is wet or dry, what the temperature is, whether there is wind)
- the environment between the sound and the listener (whether there are barriers between the sound source and the listener that can absorb or block some frequencies, whether there is competing sound)
This means trying to perform comparisons at long distances will never be accurate because the third and fourth variables will always be changing.
Now we know one of the reasons why humans wear headphones for hearing tests and dogs undergo them in small rooms.
If you are interested in how and why sound attenuates as it travels over a distance, check out this video on the inverse square law. It has a great explanation.
Is This Issue Important?
Unlike many of the things I write about that are “wrong on the internet,” this one isn’t crucial, I guess. Dogs do have great hearing at higher frequencies. The statement about four times the distance is sometimes true, and doesn’t harm dogs in the obvious ways so many myths do.
But it doesn’t matter that it can be true sometimes. The point is that we could say “two times the distance” or “nine times the distance” or even “half the distance” and it would still be true sometimes. It’s meaningless. It doesn’t give us the information we need to know. And that information is available. Hence this post.
Copyright 2024 Eileen Anderson
Related Post
Credits
- Photo of Clara howling and Zani tilting her head copyright 2017 Eileen Anderson.
- Poster “Really, Dog World?” copyright 2024 Eileen Anderson but inspired by a comment by Kate Knows Dogs. They could make a better version, I’m sure.
- Image of fake audiograms copyright 2024 Eileen Anderson. I’m reiterating that this is an average, an approximation, of several data sets and not the result of actual experiments.
- Image of Lewis looking and listening copyright 2022 Eileen Anderson.
References
- Barber, A. L., Wilkinson, A., Ratcliffe, V. F., Guo, K., & Mills, D. S. (2020). A Comparison of Hearing and Auditory Functioning Between Dogs and Humans. Comparative Cognition & Behavior Reviews, 15.
- Coren, S. (2004). How dogs think: Understanding the canine mind. Free Press.
- Dworkin, S. (1935). Alimentary motor conditioning and pitch discrimination in dogs. American Journal of Physiology-Legacy Content, 112(2), 323-328.
- Guérineau, C., Broseghini, A., Lõoke, M., Dehesh, G., Mongillo, P., & Marinelli, L. (2024). Determining Hearing Thresholds in Dogs Using the Staircase Method. Veterinary Sciences, 11(2), 67.
- Scheifele, P. M., & Clark, J. G. (2012). Electrodiagnostic evaluation of auditory function in the dog. Veterinary Clinics of North America: Small Animal Practice, 42(6), 1241-1257.
