On ABC news, Charles Gibson announced that crickets can accurately tell the temperature. This is new? If we didn't learn "the formula" as kids, surely that background awareness that becomes part of intuition has told us that crickets chirp more frequently when it's hot and slower when it's cooler.
Some years the bails of hay with which I've mulched my garden have come loaded with cricket seeds. I notice them when they are less than a match head in size and simply everywhere. A week later they are fewer and bigger, and thus for every week that follows through the summer and early fall.
Little crickets have tiny, high voices. Big crickets have smooth, middle voices.
By October I seem to be following the fate of a sole cricket, the only one left in the world, for all I know. Each night I listen, and then I forget to listen, and somewhere in that forgetting the cricket falls silent.
So here is the formula: count the number of times a cricket chirps in 14 seconds and add the number 38. You will have the exact farenheit temperature.