Dog Growls Reveal Size to Human Listeners

by jessica.lam | June 4, 2008 at 02:52 pm | 1039 views | 17 comments

The next time your ears are assaulted by a menacing growl, you may want to try to guess the size of the beast. A study has been done on the assessment of interspecies size based on vocal signals.

Lead author Anna Taylor told Discovery News "it is the depth of the growl that provides us with the greatest cue."

Taylor, a psychologist at the University of Sussex, and her colleagues recorded growls emitted by 30 privately owned domestic dogs of 22 different breeds. An experimenter would get a dog to growl by showing up at the dog's residence, approaching the canine and then staring into its eyes, which is perceived as an intimidating move and elicits a defensive growl.

The researchers then played these growls back to over 50 human listeners, who were asked, "What is the size of this dog?" During one part of the experiment, the listeners also heard growls that had been acoustically altered to reflect sounds one would expect to hear from larger or smaller canines.

In virtually all cases, the listeners correctly guessed the general size of the dog, be it a 77-pound Rottweiler or a 2.2-pound miniature Dachshund, based on just the animal's growl. The researchers were also able to predict how the test subjects would rate the artificially manipulated growls.

Taylor explained that dog growls result from two acoustic features: formants and fundamental frequency. Formants, she said, are the resonant frequencies of a voice.

"These frequencies are determined by the physical properties of the vocal tract (size and shape). Because the vocal tract itself is directly linked to the size of an individual, this means that the distribution of formants is an acoustic correlate of body size."

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Barry Artiste

at 19:42 on June 4th, 2008

I usually just stuff a Tube Sock to show my size, when clubbin.

Barry Artiste

at 19:45 on June 4th, 2008

good stuff:

jay.el, I like this story. It's good stuff. Interesting study Jay. I guess Shitz zu's are at the bottom of the Dog food chain, but they make great car alarms.

verbalink

at 19:50 on June 4th, 2008

Interesting story. My family dog was quite the barker, though quite friendly.

batwrangler

at 20:11 on June 4th, 2008

Playbow and bark.

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matabeee

at 20:34 on June 4th, 2008

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Gabis.Fromme

at 21:24 on June 4th, 2008

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elora_picson

at 23:06 on June 4th, 2008

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pestkwan

at 23:14 on June 4th, 2008

Wooo..woo....errrrr.....
May be she watch too many times "Transformer", she think that yellow toy car is "Bumble Bee" ....
Woo..woo...(Trans..form!!!)..errrr....(faster!!)

pestkwan has contributed a photo to this story.

imagemynation

at 00:58 on June 5th, 2008

small dog on a big hill

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livingdeadlaura

at 17:43 on June 5th, 2008

i was walking my dogs when i took this picture of them ganging up on a spaniel which they eventually grew tired of and let it go lol. =]

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jacquelinemingoia

at 21:08 on June 5th, 2008

Here's my pup, Lady one summer day in our backyard. Although attempting to come off tough and mean, she really is such a mush.

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magic_harry11

at 23:15 on June 5th, 2008

It's true, from the second I heard the annoying, high, but none the less spirited bark I knew it was a meager Chihuahua. But he had so much spirit, and emotion! He may be small, but his heart is bigger than his skin. I just had to capture it, though the picture doesn't do it justice.

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MacBrilliance

at 20:55 on June 7th, 2008

One of my Dalmatians, Domino.

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Dynamite Doggies!

at 12:20 on June 8th, 2008

This is my border collie, Merlin. He is the reason I am a dog trainer. After 6 years of working with him he is a well rounded and happy guy, no longer imprisoned by fear like he was when I got him. I love him so much. Jennifer Joyce, Dynamite Doggies! http://www.dynamitedoggies.com

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Barry Artiste

at 02:11 on June 9th, 2008

Okay Milo may not be a Dog, but he has the heart of a Attack Pit Bull, especially when he sees his beanie doll left outside his toybox, he lurks under the couch waiting to pounce, and when he does watch out ! He has the heart of a Rottweiller in a 8 ounce body!

Just imagine if an International Communist Spy ever Broke into our house, Why I tell ya, Milo would tear him from limb to ankle!

PixieKris

at 18:09 on June 9th, 2008

This dog thinks he is bigger than his bark.... Do you?

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ma.cherie

at 22:32 on June 19th, 2008

This is my dog feezal.
She is quite old but extremely active and still adorable!
She is absolutly tiny yet her bark is huge! haha.
I hope you enjoy this photo.

Lucy . s . Dellar

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