I found some sunflower seed shells inside of the fiberglass insulation in my basement storage wall. And, also there install a little wood stuff (refer the pic-2) in front of fiberglass insulation where I found the shells on the wall.
It doesn't look like the rats did as the fiberglass insulation is on 2 feet high wall.
Please let me know if you have some idea about why there has the shells and what's that wood stuff. Thanks.