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raldi

How to count an ant population:

1. Collect 25 ants

2. Paint a dot on their abdomens

3. Release them

4. Wait

5. Collect 25 ants again

6. Count how many are marked with dots

7. Divide 25² by this number

The result is a pretty good approximation of the size of the total ant population. To increase precision and accuracy, replace all the "25"s above with a larger number.

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What's this method called?

I'm not sure; I think I learned it from Charlie Brown's 'Cyclopedia when I was six. Wherever it was, it was about snails rather than ants; I remember that.

http://en.wikipedia.org/wiki/Mark_and_recapture

To count all the ants in the world? Presumably the rub is that you have to wait for all the ants in the world to become "well mixed", which is unlikely to happen before the ants die.

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