German and Czech researchers studying squatting dogs doing their business have found the pooches have an “inner compass” that may help explain how they find their way home over great distances.
When the four-legged friends stop during a walk to defecate or urinate, they tend to do so along a north-south axis, provided the Earth’s magnetic field is stable at the time, the scientists said on Friday.
There was no notable difference in magneto-sensitivity among breeds, which ranged from a tiny Yorkshire terrier to a large St Bernard, team member Sabine Begall of Germany’s Duisburg-Essen University said.
“We found that the dogs are wonderfully aligned north-to-south — somewhat more so when they defecate than when they urinate — but only when the magnetic field is stable,” Begall said.
For the study, published in the journal Frontiers in Zoology, the 10-member Czech and German research team asked 37 dog owners equipped with compasses to record over two years which way their total of 70 furry friends faced when they relieve themselves.
Initially, the scientists crunched the data from more than 7,000 such events, but found no clear trend. However, when they looked only at times of low magnetoelectric fluctuation, “there was a wonderful correlation,” Begall said.
The findings are another clue that animals can sense electromagnetic waves not noticed by humans and that dogs, aside from their sharp senses of hearing and smell, also have a “magnetic sense.”
In 2008, the team studied Google Earth images and found that cattle tend to graze and lie down along a north-south axis, pointing to a sensitivity also suspected in migratory birds and other species.
“There are anecdotal reports that dogs find their way home over hundreds of kilometers and an explanation may be that they use the Earth’s magnetic field for their orientation,” Begall said.
However, what exactly is going on inside a dog’s head when it poops is “pure speculation” for now, Begall said.
It may be that dogs take stock of where they are, the same way a hiker will orient a map northward, and that they cannot do this when high electromagnetic activity makes their “compass needle vibrate.”
On the other hand, she said, it is possible that, when dogs feel the urge to relieve themselves and sense a stable and comforting north-south polarity, “they are especially relaxed.”