Back when my mother and aunt were still kids, my grandmother started complaining about coming home and finding nutshells all over the floor. My mother and aunt insisted they hadn't left the shells there. My grandmother didn't seem to believe them; after all, what other explanation was there?
One day while my grandmother was at work and my aunt and mother were at home, they noticed their cat, Peanuts, jump onto the table. The black-and white cat batted a nut out of the bag, and after a few moments, finally batted it off the table and onto the floor. Their German Shepherd walked over, cracked the nut open in his jaws, then ate the nut inside. The he waited for his feline friend to bat another nut onto the floor, which the cat did, and he cracked it open and ate it. This process repeated itself for a while, until there was a mass of nutshell fragments strewn on the floor.
When my grandmother came home, my mother and aunt told her what had happened. And so, the mystery of the nutshells on the floor was solved.