The Extinction Oscillator (Seed Magazine)
By looking at the varying contributions of sinusoids of different lengths to the power spectrum, you can reliably make estimations about the trends within a data set. Music is a good example. If you examined the power spectrum of the sound waves of different instruments playing middle C, each would look unique—which is why you could tell the instruments apart. But each would have a big peak at middle C—which is how you could tell they were all playing that note. So power-spectral analysis is a very effective way to search for regularities; one has to wonder why it wasn’t used sooner on the fossil record.
