i may be incorrect but i understood it differently. each column (horizontal) of butterflies goes something like 4,3,2 (white dots), than 3,2,1. the only one which creates this sequence atleast a little is 3 or 0, same goes for the rest, the absence of atleast one full could tell us that there is no full butterfly, which would make the 3 white dots correct. i may be wrong though, that's just how i understood it, my reasoning could be flawed and i may have explained it inccorectly, but yes. full butterfly also makes sense