Page 117, ArM5 says, "Wounds caused by an animal are an Arcane Connection to that animal with a life-time of a few hours". This shows that an Arcane Connection is not/was not always a part of the thing it connects to.
So, along the same lines, is a footprint an Arcane Connection to whoever/whatever made it, again with a lifetime of a few hours?
And a related question - if a magus wants to find a woman's footprints in a forest, would you consider that Intellego Corpus or Intellego Terram?