and they all go marching...

Every summer, I get calls from people who are puzzled to find a heap of dead Argentine ants in their freezer. The ants are attracted to something, presumably an odor, in the rubber lining of freezer doors. No ant finds the freezer and goes back to recruit the others; once an ant goes in the freezer, it is doomed. But since the ants lay trail wherever they go, the ants that are attracted to the freezer all lay a trail on their way to it, and this is reinforced by more curious but equally...