The above feathers can be used as wings, shucks or for bodies if tied correctly. For some folks tying a humpy is very difficult. The fibers which make the wing get mixed up with the tail and getting the right proportions correct is hard to do. One of my major bitches with commercial fly tying wholesalers is that they are guilty of making flies which have incorrect proportions. The traditional humpy sold by Umpqua now has these giant fat bodies, stubby tails and wings with way too much hackle.
Mayflies have thin bodies and long tails.
The bodies are narrow not these awful things with stubby tails and stunted wings. A thin delicate fly is a much better imitation. Using the marabou makes the fly easier to make and much more realistic. In making the marabou humpy I use a full marabou short or grizzly marabou feather. I like the dun, natural, tan and wooduck gold colors.