We all know what a spiral looks like. Or do we? Ask your friends to describe one and they will probably trace out the form of a spiral staircase. But that is actually a helix; a curve in ...

A logarithmic spiral with a diameter of 500 μm, approximately half the diameter of a sewing needle. Curiosity about a mistake that left tiny dots on a germanium wafer with evaporated metal films led ...

Gael Mariani and Martin Scott perpetuate a series of myths in their letter about Fibonacci numbers in nature (3 September, p 19). It is true that the Fibonacci numbers are associated with a particular ...