Evolution is the greatest nano-engineer that ever existed. I always assumed that if anything was physically possible at everyday earth temperatures, forces and velocities then it would have emerged naturally from evolution, since the evolutionary benefits are clearly enormous. eg that's why room-temperature superconductivity probably can't work with commonly available compounds, if it did, evolution would have used it. So I'm puzzled that simple radio transmission/reception doesn't appear to be used anywhere, surely the ability to communicate via radio waves (rather than squawking really loudly) offers a huge evolutionary benefit. Can anyone think of an obvious reason why evolution couldn't make use of radio transmission?