How does the Shark's teeth relate to its diet?

A mammal's teeth correspond to their function: mainly, eating. Herbivorous mammals have evolved a larger number of molars and fewer canines. Carnivorous mammals have evolved a larger number of canines and fewer molars. Omnivores typically have a large amount of each. Anteaters have no teeth as they obtain their diet of ants via their long, sticky tongue, and do not chew their food.

(Were you referring to why a given kind and a given size of tooth may have different shapes in different mammals? It depends on the example.)