- News Home
10 April 2014 11:44 am ,
Vol. 344 ,
The Pyrenean ibex, an impressive mountain goat that lived in the central Pyrenees in Spain, went extinct in 2000. But a...
Tight budgets are forcing NASA to consider turning off one or more planetary science projects that have completed their...
Ebola is not a stranger to West Africa—an outbreak in the 1990s killed chimpanzees and sickened one researcher. But the...
In an as-yet-unpublished report, an international panel of geoscientists has concluded that a pair of deadly...
Tropical disease experts tried and failed before to eradicate yaws, a rare disfiguring disease of poor countries. Now,...
Since 2002, researchers have reported that agricultural communities in the hot and humid Pacific Coast of Central...
Balkan endemic kidney disease surfaced in the 1950s and for decades defied attempts to finger the cause. It occurred...
- 10 April 2014 11:44 am , Vol. 344 , #6180
- About Us
ScienceShot: Just Joking! Dogs' Play Growls Exaggerate Their Size
20 September 2013 5:00 pm
Dogs present themselves differently to other dogs depending on whether they’re protecting their food or goofing around. That’s the conclusion of a new study by scientists at Eötvös Loránd University in Budapest, Hungary. They let dogs choose between photos of two other dogs, while simultaneously playing a recording of either a food or a play growl. (The play growls were made while owners engaged in tug-of-war with their dogs; these animals were not included in the experiment.) One photo was of a dog whose size matched the growl, which reflects the length of a dog’s vocal tract; the other was of a dog either larger or smaller than the growler. When the listening dogs heard the food growl, they focused on the image of a dog who was the size of the growling dog. But when they heard the play growl, they fixed their eyes on the photo of the bigger dog, even though the growl was made by a smaller one, the scientists report in the current Applied Animal Behaviour Science. Dogs give an honest growl when guarding their food, the scientists believe, because a beagle, for instance, might be injured if it decides to play retriever. But a small dog making an “I’m really a BIG dog" growl during play likely knows that the other animal can see its size, and recognizes that it’s essentially making a joke. Dogs likely use the fake growls as they do their other exaggerated play behaviors, the researchers suggest—to reassure each other that the rough and tumble play is, after all, just a game.