It's natural and necessary as there front teeth don't stop growing, gnawing keeps them trim.
Not front teeth (incisors), but they have big sideteeth (canines).
They have front gnawing teeth designed for the job.
Rodents like mice and rats have to keep gnawing at something to keep their front teeth from getting too long.
Beaver
Most mammals have teeth that cannot grow back or repair when they are damaged. Mammals that gnaw on things experience a lot of wear and tear on those teeth. Eventually the teeth are so worn down they are useless, and the animal can starve. Rodents evolved to have front teeth that grow constantly. For them, gnawing on things just prevents the tooth from growing too long.
no swans do not have teeth. i have a picture with a swans mouth open trying to bite and it clearly shows they have jagged edges on the beak that look like teeth.
Basically. Gnawing is more of a front-tooth type of chewing, while plain chewing usually uses the back teeth.
hedgehogs have large incisor's specialized for gnawing!!
Hermione's teeth were enlarged by Draco Malfoy.
Mice show there teeth as a self defense, for protection, and for gnawing as an escape plan
These three animals come from the same taxonomical order Rondentia, commonly called rodents. They have sharp front teeth used for gnawing.