Guinea pig
Red cedar (Eastern or Western) and pine, both softwoods, were commonly used as bedding, but now these materials are believed to contain harmful phenols (aromatic hydrocarbons) and oils. Bedding materials made from hardwoods (such as aspen), paper products, and corn cobs are alternatives. Guinea pigs tend to be messy; they often jump into their food bowls or kick bedding and feces into them, and their urine sometimes crystallizes on cage surfaces, making it difficult to remove. After its cage has been cleaned, a guinea pig typically urinates and drags its lower body across the floor of the cage to mark its territory. Male guinea pigs may mark their territory in this way when they are put back into their cages after being taken out.