It's Optimal. It Must Have Evolved!

You're wandering through the countryside and you find an antenna array with a high signal-to-noise ratio. You wander some more, and find another; it looks different, but still has a near-ideal SNR. After finding half a dozen of these, you have a "Eureka!" moment: "They came about by blind, unguided processes!"

If this sounds absurd, read a paper by Garud Iyengar and Madan Rao in PNAS, "A cellular solution to an information-processing problem." From the title and description, you would think t...