(Erin Ruberry - Discovery)
You know how annoying it is when your dog has to scratch, sniff and turn in circles to find the perfect place to do his business? There may actually be some science behind the seemingly random movements.
A new study published in the journal found that dogs "preferred to excrete with the body being aligned along the North–south axis."
In other words, your pup has a butt compass. And listening to that internal compass is more than just a preference, according to the study: "Our analysis of the raw data (not shown here) indicates that dogs not only prefer N-S direction, but at the same time they also avoid E-W direction."
The scientists observed 70 dogs of 37 breeds during a two-year period during walks in open fields, "and routes of walks were routinely changed to exclude or limit pseudoreplications which would arise when dogs are defecating or urinating at just a few places within their kennel or house yard."
This is only true when the Earth's magnetic field is calm -- about 20 percent of daylight hours, the researchers said.
Why are dogs so sensitive to the Earth's magnetic field lines?
"We don't know yet," study coauthor Dr. Sabine Begall told Huffpost Science, "We can only speculate. Since it is the polarity that has an effect on the alignment direction, it could be that the dogs somehow calibrate their compass or read their 'mental map' during the walks."
Take a compass next time you walk your dog and let us know what you discover! Do you believe it?