Why Do Mice Gnaw on Hard Things?

A mouse's front teeth never stop growing. They must keep wearing them down, so they gnaw on hard things. If they didn't do that their teeth would keep growing until they couldn't close their mouth . Mice can nibble into concrete and even nibble holes in cans made of aluminum because they have such hard and sharp teeth. In the wild their food is low in nutritional value so they are chewing all the time. If they are around humans the food is better so they eat less. This, however, would result in their teeth getting too long were it not for their habit of gnawing on anything and everything to keep them very short and harp.