What can fishes with jaws do that without cant?

Fish with jaws can move their jaws independently of their skulls, which allows them to open and close their mouths to capture and eat food. This is because they have a movable joint between the upper and lower jaws, which is known as the jaw joint. This joint allows the jaws to pivot, allowing the fish to open and close its mouth. In contrast, fish without jaws, such as sharks and rays, have a fixed joint between the upper and lower jaws, which means they cannot open and close their mouths independently of their skulls.