behavior
--------

all ants come pre-programed to seek and follow certain kinds of objects. 
the initial weights of wander, panic and follow are determined at birth
randomly or according to a `most optimal' list

ants die after N moves if they don't return to the nest; ants will only
return to the nest if they find what they are looking for

the nest has a list of objects, both specific and classes that are to 
be searched for; each ant may contain a copy of this list or any part of
it, depending on a memory attribute

ants keep track of a path back to the nest, but if they become trapped they
will die.

the nest keeps track of all the active ants and spawns a new ant whenever
a) an ant dies of starvation (based on a fertility %)  or b) a time threashhold 
is reached with no new deaths (ie, successful colonies grow more quickly)

scent objects keep track of ant movements; when an ant is returning
to the nest with an object, another ant can follow that trail to the source
of the object. when an object causes an ant to enter panic, a panic
scent reflecting the level of the ant's panic is deposited. Scents decay. 

depending on how paniced, an ant may drop an object when it becomes so.

behavior tree
-------------
wander
  causes ant to move randomly weighted by scents and objects
  --affected--
	has a fixed weight
	scent - in room and neighbors
	  |
          *-enter `panic'
	  *-enter `flee'
	  *-enter `follow'
	  *-drop object
	object - "
	  |
	  *-enter `panic'
	  *-enter `flee'
	  *-enter `follow'
	  *-enter `lift and carry to home'
	  *-drop object

wander_panic
   cuases ant to move quickly (two rooms or more at a time), ignoring
   scents
   --affected--
	time passage causes weight to fall gradually


wander_flee
   cuases ant to move semi-randomly away from a scent or object
   --affected--
	proximity to object, as the ant gets farther away, the weight
	of this behavior drops

    
wander_follow
  causes ant to move toward an object it has had contact with and 
  continue to follow it
  --affected--
	gradually drops after the passage of time. if the followed object
	is too far away, weight drops dramaticly

lift and carry home
  causes ant to take an object and return to it's nest, following its
  internal navigation guide
  --affected--
	reaching home causes object to be dropped and weight returns to
	0