We had a dog that posed something of an interesting side note on the original article. The authors note that "alignment" when dogs pee is less consistent than when they poop.

Since the "whiz stream" is normally not aligned with the body of the dog, the discrepancy might be caused by failure to consider whether the dog aligns the "whiz" (or the poop) geomagnetically rather than just the body. The "direction of poop" would be almost exactly parallel to the spine, while the "direction of pee" would be at some, possibly more random, angle to the body orientation.

Unfortunately, even had I thought to examine this idea with our dog, resolution of the question would have been difficult, as he "assumed the stance" in classic manner, with rear foot raised impressively, but then directed his "pee stream" precisely parallel to his body so that it impacted axactly dead-center on his front foot.

Without some misalignment between body and squirt, separation of the possible influences would have been quite impossible.

(Not all test subjects are good subjects for study.)

John