In 2013, a group of researchers discovered that dogs are sensitive to small variations of the Earth’s magnetic field. Here were their results:
Dogs preferred to excrete with the body being aligned along the North–South axis under calm MF [magnetic field] conditions. This directional behavior was abolished under unstable MF. The best predictor of the behavioral switch was the rate of change in declination, i.e., polar orientation of the MF.
Translation: Dogs prefer to poop facing either north or south.
By analyzing their excretion directions under different magnetic field conditions, the team found that dogs respond to tiny changes in polarity.
A useful reminder that the world is not always as random as it seems.