We used to have a 90# pit bull. She was gentle and, while powerful, relatively non-destructive in the house. We now have two dogs, one of which is a 9# chihuahua mix. She is a whirlwind of destruction, gnawing all manner of clothes and towels to bits. Ferocity* matters more than size, I guess.
That's her, officer! The little one! I'd recognize her anywhere!
* - Well, ferocity or an abundance of nervous energy.