Hey Koryos, so birds spend a shitton of time messing with and caring for their wings, right? Do bats do anything similar? Or does the lack of feathers let them treat their wings basically just like arms? (I know they can tear the membrane but I'm thinking more abt every day maintenance.)
Good question! For flighted birds, feathers require special maintenance via preening, where they use their beak to put oil from a gland in their backs (uropygial gland) over each feather. This keeps the feathers flexible and waterproof, as well as keeping them clean.
By contrast, for bats the flight surface is composed of (usually) bare skin. Skin is a lot better at maintenancing itself than filaments like feathers or hair, if you consider our own low-maintenance bare skin. However, the bats I worked with did spend hours each day cleaning the surface of their wings, probably to keep the skin soft and flexible. Also probably, in the case of the males especially, to stink themselves up from their scent glands.