[ExI] ants again

[spike]

I commented a few weeks ago on some ant stuff I was going to post here, so
those who have no interest in ants, do take the opportunity to bug out
forthwith.  I mean that in a polite, entomological way of course.  {8^]

Now to my recent experiments, to be described  Flies react to a hand coming
in their direction, but ants do not.  They seem to have no concern if one
appears to be getting ready to swat them.  They go about their business with
no concern that it might be their very last second of earthly existence.
But I was wondering if their eyes may just be extremely near-sighted, so
they don't see anything that is more than a few cm away.

Last season I was trying to get ants to pass the double straw test: get a
two-way migration going, then insert a short section where the ants must all
pass thru two straws, then see if I could get them to set up one-way straws.
I never did get them to do that, so I set up a simpler, two hole experiment,
set up a paper strip with one hole about half a cm in diameter thru which
all ants must pass, then put up a divider which converts the passage to two
adjacent holes, each about 2 mm in diameter.  The 2mm holes are large enough
for a single ant to go through easily, but two ants cannot pass each other.
So if they figure out to make the holes one-way passages, then the traffic
flows smoothly, otherwise, they ball up and no one gets thru.  They block
each others' progress.

I may have not found the right combination, but I have not been able to get
the ants to make one-way passages.

So now I ask why, and I came up with an interesting notion, which I have
tried to confirm or disprove, which I call the kielbasa theory.  Imagine
yourself at a festival in a foreign land.  You are hungry and thirsty but
you know nothing of the language.  People are milling around everywhere,
when you see someone carrying a steaming plate of kielbasa and sourkraut,
with no bites taken from it.  You wander in the direction that person came
from, looking for another kielbasa carrier.  Perhaps you find the source and
get your lunch.  Now you look around for someone returning with an empty
plate and an empty beer mug, and you reason that the direction from which
she came might have picnic tables.  

The kielbasa theory is that perhaps ants form their migration paths by
seeing what the other ants coming the other way are carrying.  In my case,
the ants appear to climb the tree, milk the aphids, then take the nectar
down into the ground.  Perhaps the empty-mandibled ants look for nectar
carrying ants, then fall into a line heading in the direction from whence
the nectar carrier came.  Perhaps the nectar carriers look for
empty-mandibled ants and head off in that direction looking for the
subterrainian nest.  This is what I call the kielbasa theory.

I bought a small portable air compressor with a one-gallon tank and a
trigger nozzle, which I call my ant-poofer.  The experiemnt is to find or
create a two-way migration across a flat surface like the sidewalk, then
take a shoebox bottom with the ends cut out, set the box upside down across
the ant migration and quickly poof away all ants in the segment under the
box.  So now we have a two-way migration, within a couple seconds a gap
appears about 12 cm wide.  Now I watch the ants on either side to see how
long it takes to re-establish the path.  This experiment suggests a number
of questions, such as: Which side of the path repairs itself first?  How do
the ants reason out where they are supposed to go?  Do they do it visually?
Or by some kind of chemical signals?  Do I have far too much time on my
hands?

spike