Rats in an Attic
The rat gained entry into the attic through a torn bird screen.
Pack rats like to always have an alternative escape route whenever possible. Since there was no insulation, I could clearly see where the rat probed a gap in the sheet rock.
The rat settled on chewing a hole through a solid 2x6 as you can see in the picture below.
The pack rat in this attic did a significant amount of damage to the wiring in the attic. Mostly by striping off the outer insulation. You can see pieces of the insulation below with the teeth marks clearly viable.