“A duck’s quack doesn’t echo, and nobody knows why,” is an oft-quoted scientific ‘fact’ of the type that spreads like wildfire via WhatsApp groups before you literally hear it from a bloke down the pub.
But you won’t find this fact (alternative fact, fake news, post-truth, misinformation) in any reputable scientific paper because of course a duck’s quack doesn’t defy the laws of physics and like every other sound that isn’t produced in a vacuum, it echoes.
But why is this myth so popular and from where did it originate?
The Bird Spot team first heard the claim back in the 1990s (or the late 1900s as the Zoomers have started to call it which makes us feel really, really old). However, it’s likely it dates back further than that but unfortunately we can’t find any supporting evidence to confirm either way.
How it originated isn’t clear either, although a few suggestions have been put forward.
Ducks tend to live in open spaces away from large reflecting surfaces such as buildings or mountains so there often isn’t anything nearby for the sound waves of the quack to bounce off and produce an echo.
Some species of duck produce very quiet quacks so perhaps whoever made the original claim simply couldn’t hear an echo. Or perhaps the topography of the area around the duck’s habitat caused an acoustic shadow to occur (a phenomenon where even very loud sounds can’t be heard due to obstructions or a disruption of the sound waves).
Wherever the myth came from, by the turn of the century, it was so prevalent that in 2003, scientists from Salford University’s Acoustics Research Centre, led by Professor Trevor Cox, decided to bust it once and for all.
Professor Cox has worked on all sorts of important projects such as designing rooms for music to be played in, improving public announcements at train stations for people who wear hearing aids, and inventing one of the world’s largest whoopie cushions.
For this project, he borrowed a duck called Daisy, and firstly placed her in an anechoic chamber, a room in which the walls, floor, and ceiling are covered with sound absorbent materials, so that echoes are deadened.
He then put her in a reverberation chamber, a room with hard walls which results in cathedral-like acoustics and where the sound echoes for a long time.
They also used a computer to simulate Daisy’s quack in a concert hall and as if she was flying in front of a cliff.
The team of researchers recorded the resultant quacks in each room, as well as the virtual quacks, and analysed the sounds.
What they found was that in the anechoic chamber, the quack was a little softer than expected and any echo was masked, while in the reverberation chamber, although it was quite hard to hear the initial quack, it was quite clear it did echo. In fact sounded a little sinister, according to the researchers.
But the recordings and analysis also showed that the quack didn’t finish abruptly but had a long fading ‘aaaack’ sound at the end, and meant it was hard to tell the difference between the quack and the subsequent echoes.
Professor Cox said, “What all this shows is that the duck’s quack fades away; it sounds like it quacks for a long time.
“Because the duck’s quack is rather quiet anyway and the echo comes on the back of a fading sound field, it is as if the echo is being masked. You just don’t hear the echo very well and that’s probably how the myth arose.”
So, although a duck’s quack certainly does echo, there does seem to be a scientific explanation for how this myth came about. Although the experiment was just a bit of fun for the Salford team, the results will play an important part in their work around the construction of buildings such as concert halls or cinemas, and the design of cars.
And what of Daisy? The duck, who was borrowed from a farm in Cheshire, was, unfortunately, later eaten by a fox. However, her daughter, unlike her echo, lives on.
4 Responses
Keep it simple that’s were it hindered the outcome.
RIP Mom <3
Poor Daisy! She didn’t deserve the fate that stumbled upon her. We’ll remember her for her scientific influence though, thankfully debunking this weird fake news with her quacks.
RIP Daisy, your important and awe-inspiring contribution to science shall be remembered with great fondness and gratitude.