Why ant trails look so nice and straight?

[Dario Ringach]

Richard Feynman discusses in one of his books how interesting
is that pheromone trails from a food source to the ant hole
are pretty straight, even though the the initial trace laid
by the first ant which found the food and went back to the hole 
could have been pretty wiggly and far from straight.

I was wondering if there is any good information about how
the shape of ant trails change over time.  Does anyone know
if research has been done on this topic?

Thank you in advance.

-- 
Dario Ringach              |    office: (212) 998-7614	  lab: (212)
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