Hi everyone, OP here. I was speculating (apologies) that some "knucklehead" was to blame. In fact I don't know if a passenger brought rotting fruit onboard or where the ants came from. Wow Air has not made that public. The question is whether the presence of ants -- wherever they came from -- is "extraordinary" or not. It's not an easy call. Anyway thank you for all who have contributed. CM