What wild visitor helps Brian figure out how to build a fire? How? What does the fire meant to Brian?nothing else

When Brian is asleep in his cave like dwelling, a porcupine wanders inside.  As he seeks to get rid of it, he throws the hatchet- his hatchet- against the cave wall.  He notices the sparks that come off of the wall in the process.  Brian uses this moment to work on developing a fire.  The creation of fire means a great deal to Brian.  For one thing, fire allows Brian to develop a chance to develop a signal fire that can be used to attract a rescue mission.  Another reason fire is important is that it becomes a source that will allow Brian to cook food.  At the same time, the fire becomes one of the first things that Brian does which shows a chance of being successful in his endeavor.  At the same time, Brian learns to care and tend for the fire, as if it is his own creation, helping Brian to develop a notion of companionship in his time in the wilderness.