In an interesting application of satellite imagery analysis, German researchers used Google Earth imagery to observe that cows at rest tend to orient their bodies in a north-south direction. The researchers studied photos of more than 8,000 cattle in 308 herds around the world. The study aimed to extend the theories of magnetism to larger animals, after seeing similar behavior in birds, fish whales and rodents.
This phenomenon appears to have evaded hundreds of years of herders. In other animals, this magnetic sense is used for navigation. There’s no consensus on why cows have this sense or what benefit it might have.
For more details about the study, read this feature in the Los Angeles Times.