I posted a poll on the reef fishes forum that I would apreciate if y'all (that have a YWG) could cast your vote.
http://archive.reefcentral.com/forum...hreadid=315164
Oh and I forgot to mention this in the post above in my reasons for my theory:
5) I also think that this could be a natural protective function in nature. A YWG that is with out the protection of a cave where it can hide from danger can change in color to match the color of the general color of the substrate on the reef.