Termite Damage Drywall
Out here in the Wild West, termite damage drywall go hand in hand with the mess they cause. If you’re lucky enough to see evidence on the foundation slab, but here in Arizona the stucco sometimes goes below the rock.
I don’t know how they do it, but they will pop out on a picture frame and just start to eat away. In this case some type of cardboard behind a shelving unit. I’ve seen books eaten and completely ruined, the little termite aren’t big but there are many.