Question: do you think a zebra is white with black stripes or the other way round?

Daniel Mietchen answered on 22 Jun 2010:

I have no precise idea about zebra stripes but in similar acts of pattern formation (e.g. on the surface of shells, about which I was once asked in an exam), there are typically at least two interacting processes (two would seem a reasonable assumption here). So I would say both. A brief literature search supports that for stripe formation in the fruit fly (couldn’t find any relevant piece for zebras – they are not really frequently studied in the lab).