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dmix · 2016-09-02 · Original thread
The memory of most ant species only lasts about 1 day. So for the group memory of the hole to persist there would have to be some sort of pattern of ants going to the hole and not going in, or some sort of warning sent near the hole. Otherwise there isn't an obvious way for this memory to persist in the colony.

Otherwise group memory can persist for years or decades to things such as the location of food sources. Which I learned in the wonderful book: "Ant Encounters: Interaction Networks and Colony Behavior"

https://www.amazon.com/Ant-Encounters-Interaction-Networks-B...

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