Dogs do a lot of strange things when they poop—they sometimes kick their back legs over it (find out why here) and some dogs even eat it, but even more prevalent are dogs who spin around before squatting.
A video by DNews discussed various theories surrounding this behavior, including that patting down the grass or dirt prevents the waste from sticking to their fur, and a more recent theory in which researchers determined that dogs seem to prefer to do their business while aligned north-to-south with the earth's magnetic fields. Also, the video explains, dogs avoided a east-to-west orientation.
Check it out here:
Curious about more strange (and sometimes funny) dog behavior? Check out these topics for more information.