These are paper sculptures of birds’ wings – four specific categories of birds’ wings. As explained by their creator:
This is my paper sculpture of the basic structural differences of the wing types in birds: High Lift, Elliptical, High Aspect/Soaring, and High Speed. Some of the most important differences were the inclusion of wing slots and the alula.
That’s a lot of little snips done just right.
I found this on Clip Its Wings Art (via Scientific Illustration). Would kinda like to see some more….