They are all insulators. Wisconsin, USA We use insulators to keep us warm. Squirrels sleep in leaves in the winter. Birds use sticks to build nests. People use styrofoam to insulate their houses.
Straw is an insulator.
If you jump into a haystack, it will warm you up. Dirt can keep animals warm. Fiberglass is in my mom's truck. Fiberglass makes people itch. I have a blanket to sleep with.