The idea of 'random walks' pops up in areas from biochemical reaction pathways to animals' foraging strategies. A central question — how likely is it that a walker is somewhere for the first time? — now has a simpler answer.

In the silence that precedes the onset of hearing in the developing auditory system, it seems that the cells of a transient structure known as Kölliker's organ are capable of generating their own 'virtual' music.