Did you know that horses have their own 'GPS' (Global Positioning System)? Wherever they are, horses can orientate themselves on the basis of magnetic fields.
Have you ever wondered why your horse is much more forward on the way home than when you are leaving the stable? Even when riding with loose reins in an unfamiliar area, horses seem to know which way is home. How is this possible? Do horses have a built-in 'GPS'?
Horses use two types of orientation. Firstly, they create a mental map (Type I Orientation). Secondly, they have a type of compass orientation (Type II Orientation), in which animals utilize the magnetic field around the earth. Horses use a combination of both.
Horses have a very good memory. They remember an important location through the use of different visual 'beacons' in the area. This has developed from their wild origins - It is useful when you live on an open steppe and have to remember where the water is, to know where you are on a piece of terrain. A horse then knows, for example, that the water can be found at the third tree on the right, at a certain distance down a mountain. Using a mental map is also one of the most important ways of navigating for humans. However, whereas we record the main landmarks that are important to us on a map, horses 'draw' this map in their head and remember it.
Horses also create orientation points with the help of scents. Along the route, they drop feces, which they can use later on to find their way back to a location. Other horses also use these fecal piles as directions.
Even without 'manure maps' though, horses can still find their way around. The story of a working packhorse on the beach of Costa Rica was once described. The horse could exactly follow the route of another horse that was a stable companion and had walked home over the same beach an hour earlier. The horse walked for about a kilometer with its nose one centimeter above the sand, zig-zagging over the beach. As soon as he could smell the companion horse, he changed direction, parallel to the water line in the direction of his stable, six kilometers away. He continued to walk for about 300 meters with his nose one centimeter above the sand, after which he lifted his head to a height of 50 centimeters. If he lost the scent again, whenever a wave covered the beach, he would simply repeat his zig-zag pattern with his nose to the ground, until he got back on the track again.
A mental map only works if the horse already knows the environment, or if other horses have gone there beforehand. What about an unknown territory? How does a horse find its way home then? Not much research has been done on this yet, but it seems that horses use the magnetic field around the earth to orientate themselves. In an initial study, horses were placed singly in unfamiliar environments, at different distances from their stables. Astonishingly, the horses could easily find their way back to their stables, up to a distance of 80 kilometers away.
In a second study, horses were placed at locations between 15 and 25 kilometers from their home. Some horses were equipped with a magnet hanging around their neck. The horses with a magnet were less able to find their way home. Horses without a magnet walked in the right direction within 15 minutes. The magnet probably disturbed the horses’ ability to orientate themselves through the magnetic field, and so they got lost.
Horses are not the only animals with compass orientation. Salmon, as well as some birds and turtles, use compass orientation for their migrations.
Formation of the herd
The ultimate proof that horses can sense magnetic fields came in 2009, from a researcher from Germany. Through Google Earth, she investigated the standing direction of 1,150 horses in 264 locations. Horses, like, for example, cows, reindeers and deer, were found to preferably stand in the direction of the magnetic field and not, as previously thought, in the direction of the wind or towards the sun. On average, two-thirds of the animals were standing in the direction of the northern magnetic pole, and one-third towards the southern pole. In this way, the entire environment can be closely monitored by the herd.
Rein Sensors and GPS
As you can see, horses don’t need GPS, and with a horse you never have to worry about losing your way home. Even so, for our own use and for analysis purposes, Ipos Rein Sensors are equipped with actual GPS.
Wiltschko R. 2012. "Magnetic Orientation in Animals".
Janzen D.H., 1978. "How do horses find their way home?"
Budiansky S., 1997. "The nature of horses, Exploring Equine Evolution, Intelligence and behavior."
(In German) Hunt, 1999, Orientation and WayfindingDobel, 2012, "Orientierung: Forscher entdecken magnetische Sinneszellen."
(In German) Klein, 2010."Ausrichtung von Pferden unter dem Einfluss von Hochspannungsleitungen".
(In German) Klein, 2010. "Magnetorientierung bei Pferden."
Mouritsen, 2014, "Magnetoreception in Birds and its Use for Long-Distance Migration."
(In German) Weisse, 2014. "Magnetorezeption bei Säugetieren." http://www.daltonmavo.nl/nask/images/antwoorden/magneetveld_aarde.gifhttp://sfk.gfz-potsdam.de/images/nsmag.jpg