Mammals are unusual - compared to reptiles, fish and dinosaurs - in having three things, teeth that have different shapes for different functions, teeth that fit together very precisely, and teeth that do not replace themselves in adulthood. Mammalian teeth are therefore quite precious, an old elephant that has worn its molars down will die of starvation. The innervation of teeth prevents - to some extent - accidental breakage through biting on very hard objects.
A shark replaces teeth continuously, they will bite hard on iron bars. It makes little difference to them if they lose a dozen teeth. Tiger sharks in particular are very indiscriminate in what they will bite and indeed swallow.
Mammals are unusual - compared to reptiles, fish and dinosaurs - in having three things, teeth that have different shapes for different functions, teeth that fit together very precisely, and teeth that do not replace themselves in adulthood. Mammalian teeth are therefore quite precious, an old elephant that has worn its molars down will die of starvation. The innervation of teeth prevents - to some extent - accidental breakage through biting on very hard objects.
A shark replaces teeth continuously, they will bite hard on iron bars. It makes little difference to them if they lose a dozen teeth. Tiger sharks in particular are very indiscriminate in what they will bite and indeed swallow.
