Researchers have discovered that your best furry friend poops in alignment with the Earth's magnetic field.
A team of Czech and German researchers found that dogs actually align themselves with the Earth's magnetic field while they poop. The researchers measured the direction of the body axis of 70 dogs from 37 breeds during 1,893 defecations and 5,582 urinations over the course of two years, and found that dogs "prefer to excrete with the body being aligned along the North-South axis under calm magnetic field conditions."
It is still enigmatic why dogs do align at all, whether they do it 'consciously' (i.e., whether the magnetic field is sensorial perceived (the dogs 'see,' 'hear' or 'smell' the compass direction or perceive it as a haptic stimulus) or whether its reception is controlled on the vegetative level (they 'feel better/more comfortable or worse/less comfortable' in a certain direction). Our analysis of the raw data (not shown here indicates that dogs not only prefer N-S direction, but at the same time they also avoid E-W direction.
Keep in mind that these tests were observed when the dogs were off leash, in the middle of an open field. So don't think your dog is special when it faces E-W while pooping on your neighbor's driveway on your next walk together...