8/25/03
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How do they do it?
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Semiochemically: deposit pheromones
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10-20 signs, many signal tasks
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ants detect pheromone gradients and frequency
of encounter
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Follow trails imperfectly
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exploration
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Feedback reinforces successful trails
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biased randomness
Much we donÕt know, but this seems to be framework of much of collective behavior
E.g., decreasing odor of soldier
Þ produce more
Note that a ÒbugÓ (following trails imperfectly) is exploited as a ÒfeatureÓ
Natural computation often makes productive use of noise, errors, imprecison, randomness, chaos, etc.
(Johnson 76, 243-4n74, 244)