Google Earth has become the epicenter of an international dispute among competing researchers as to whether or not cattle have a mysterious but widespread tendency to orient themselves along a magnetic north-south axis when grazing or at rest. Though the whole thing is worth a chuckle, it’s also a reminder that Google Earth and Google Maps are emerging as important tools in fields related to sustainability, including renewable energy and energy conservation, not only for professional researchers but for the general public as well.
Using Google Earth to Spot Cattle
The magnetic cow ruckus has its origins in a 2008 study published in the Proceedings of the National Academy of Science, in which a team headed by German scientists used images from Google Earth to conclude that herds of cattle routinely align themselves along the Earth’s magnetic field. A Google Earth blogger responded with an ad hoc survey of his own, and his admittedly unscientific conclusion was that cows were indeed aligning their bodies along a north-south line, but only because that was the shortest distance between them and their feeding bins.
Google Earth Provides More Evidence…
In 2009 the same German-lead team found evidence that supported their original conclusion. They studied the effect of magnetic fields from high-voltage power lines on herds of cattle and determined that proximity to the power lines can disrupt the bovines’ magnetic sense, causing them to align randomly. The phenomenon dissipates as the cattle move farther from the lines, as described in an article in scienceblogs.com by writer Ed Yong. Yong also pointed out that magnetic orientation in mammals has been known to scientists for quite some time, but the research has generally been confined to animals that are easy to study in a laboratory, namely, small mammals such as bats and hamsters. Google Earth provided the first opportunity to study large mammals on a systematic basis.
As chronicled in a recent article in nature.com by Daniel Cressey, earlier this year a research team based in Czechoslovakia attacked the German team’s findings with a new set of Google Earth images that failed to indicate any magnetic alignment. The German team argued back that the Czech team selected individual cattle subjectively rather than surveying herds, and it included numerous images of cattle near power lines, and images that were not cattle at all but were sheep or even bales of hay. The issue is dormant for now, as Cressey reports: the Czech team lobbed back a snappy defense of their research and then announced their disinclination to pursue the matter further.
Google Earth, Google Maps and Sustainability
Google Earth is already being used as a tool for getting the most bang for your solar energy buck in California, where researchers at the University of California have used it to create a solar power map that lets homeowners predict the most efficient placement for solar panels. Meanwhile, Google Maps is being used as an urban forestry tool and an EV charging station locator. While the magnetic cow mystery is still somewhat up in the air, the agriculture industry
The Last Word on Magnetic Cattle
It is tempting to point out one obvious explanation for magnetic alignment in cattle, which is that many domestic cattle actually have magnets – real magnets – in their stomachs. Yes, really.
Called cattle magnets, these are small, slim rods typically force-fed to young cattle at branding time. They probably feel nasty going down but they neutralize the effects of tiny bits of iron that cattle can swallow while grazing, such as pieces of barbed wire, nails, and other detritus known as “tramp iron.” The cattle magnet settles in a forward stomach where it can catch and hold tramp iron safely for the lifespan of its host. However, the German research team had also surveyed deer, few if any of which were sporting cattle magnets, and found the same distinctive orientation. Until further research is conducted, the magnetic cow mystery will remain just that – a mystery.
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.