One of our survival qualities of being humans involves the instinctive sensing of information found in the tracks that people or animals leave behind.  Of course, like all innate talents, it is a sense that needs to be used and developed to be helpful.  Native Americans honed this talent to the degree that a trail in the mud or snow revealed a wealth of information about the person or animal who left their signature as if they had signed it.  It was a careless person indeed who left tracks so bold that every thing was revealed except the name of the individual or the color of their horse.