They look a lot like the flies the natives along the Amazon River in South america use. Anyways reminds me of lots of times on the river, when your having a great day. You've been using the same fly for hours and its working almost every cast. You look at your fly its tattered and torn material hanging off it. Doesn't even look like a fly anymore but hey it works like magic, finally you lose it in a tree. Tie on a brand new fly the exact same fly you where using and they wont touch it. Too funny, grab two rocks crush the fly up a bit. Ok looks a little like that last one.