Have you ever wondered why dogs turn in a circle before doing their business? They're finding the earth's magnetic field to align their bowels and bladder movements and very much prefer a north-south axis. Other animals can sense the magnetic field, perhaps including us. Humans have a protein in our retina which may allow us to sense it, but we haven't used it for millennia. Click on this pin to follow a very clever dog's adventures through a time portal!
