Fox skull: from a typical carnivore (meat-eater)

Carnivores generally have long, sharp front teeth which help them catch and tear into their prey. The back teeth are narrow and sharply serrated, much like the blade of a knife. They are used to cut meat into smaller chunks. Insectivores (like moles) eat insects almost exclusively, and have fine, needle-like teeth.

Squirrel jaw: from a typical herbivore (plant-eater)

Herbivores have broad, flat molars (back teeth) with rough surfaces, which are used for grinding up tough plant tissues. Many herbivores (like squirrels) have chisel-like front teeth used for gnawing through wood or hard seeds. These teeth grow continually to avoid being worn down with use. Herbivores often have a gap between the front and back teeth to allow space for repositioning plant tissue as it's chewed, since much chewing is required to break it up.