I'd expect the fine detail of the (the 'rib patterns' as you call them) to have a randomness within the larger (genetic) picture, thus indeed be unique to the individual. In nature it wouldn't be efficient to "code" everything to the last micron... and species that are too fixed in their build cannot adapt to changing circumstancesAnother sitting duck, or a yellow-spotted whiteface to be more exact. Possily the same individual, this time it held the wings steady but moved the tail so I could not use the last picture in the stack.. I noticed another odd thing, the rib patterns in the wings are actually not identical on right and left side, at least when it comes to the smallest sections. I wonder if the pattern is unique for each individual then, like our fingerprints..?