He is man’s best friend. Its intelligence and adaptability are legendary. Dogs also have a great nose. And apparently they still have surprises in store for us. Dogs are led by the earth’s magnetic field.
The finding is the first in dogs, says Catherine Lohmann. She is a biologist at the University of North Carolina at Chapel Hill. The navigation skills of dogs are less researched than that of birds, for example.
To the south
There was already evidence that dogs and other animals perceive the earth’s magnetic field. In 2013, Hynek Burda from the Czech University of Life Sciences in Prague made an unusual discovery. Dogs tend to orient themselves from north to south when urinating or defecating. This behavior is associated with marking and recognizing the area. Burda argued that targeting helps dogs determine location relative to other points. However, the stationary orientation is not the same as the navigation.
The student Kateřina Benediktová placed video cameras and GPS trackers on four dogs and took them on an excursion into the forest. Dogs would chase the smell of an animal for an average of 400 meters. The GPS tracks showed two behaviors on their return trips. In one case, a dog would return to its original route on the original smell. In the other behavior, called the scan, the dog returns on a completely new route (called the scan).
They noticed something strange. During a scouting race, the dog stopped and ran about 20 meters along a north-south axis before starting to turn. These short runs seemed to be aligned across the magnetic field. They expanded the project and released 27 dogs on several hundred trips over 3 years.
223 cases of scouting races were observed, in which the dogs covered an average of 1.1 kilometers on their return. On 170 of these trips, the dogs stopped before returning. They ran about 20 meters along a north-south axis. When the animals did this, they tended to return in a more direct way than when they did not. Authors report on eLife.
Burda believes that dogs run along a north-south axis to find out which direction they are. Dogs are led by the earth’s magnetic field. It’s like they have a compass with them.
Adam Miklósi specializes in dog behavior. He says designing magnetoreception experiments is complicated because it is difficult to trust an animal only in that sense. “The problem is that you have to exclude everyone else to test the magnetic sense or any sense 100%.”
Burda and Benediktová take a different approach. In a new experiment, they will attach magnets to the dog’s collars to disrupt the local magnetic field. Miklósi says it would be no surprise to discover that dogs can use the magnetic field to orient themselves. It appears to be an ancient skill and could be present in any mammal that crosses large areas. Lohmann agrees. “Hopefully a lot of animals can do this to come home after the hunt,” he says, “and it’s great to see it on a dog.”