Saturday, November 07, 2015

Marauder Ants and Stigmergy

Members of the [road] construction crews [of marauder ant colonies] expend their efforts foraging for building material rather than food.  It is likely that no communiques pass among them.  Rather, like compulsive bricklayers unable to go by an unfinished wall, passing ants respond to the ongoing building project, and the structures emerge without active collaboration.  The portions of the walls that are suitably positioned and shaped along along a trail attract the most attention from passersby bearing soil bits.  As a result, the arcades rise to completion where they are most needed, without a blueprint, and damage to them later is repaired without a fuss.

Accomplishing large projects without communication is called stigmergy.  The marauders' approach to building has been duplicated by robotics experts, who have discovered that its cheaper and easier to achieve a goal such as piling up small objects with a group of simple robots responding to the sort done thus far than with one large, more intelligent robot.  Stigmergy is at work in such websites as Wikipedia and Google as well, where many people add their insights to the statements and choices of others.

-from Moffett, Mark W., Adventures among Ants: A Global Safari with a Cast of Trillions p. 23-24 (U. Cal. Press 2010), a simply fantastic book.