Sharks have been killing and eating other animals for a long time. They do this in a manner somewhat different from other large predators. Welcome to our second edition of Nature’s Knives: Sharks.
There are two appreciative differences between shark teeth and those of most other predators: sheer number and the fact that they are replaceable.
DISCLAIMER: I am painting really broad strokes here. This is not a zoological textbook. For these purposes I am more interested in the general method than the anatomy of every single shark specie.
For their size, sharks tend to have small teeth. If you compare the proportional length of their teeth to other animals they are downright tiny. Many other predators rely on a few really long teeth to puncture the vitals of their prey. You have got to get deep penetration to cause death.
Sharks do not need to go this route because they go by another. They rely on a much larger bite radius. Sharks have multiple rows of sharp teeth and their mouths are proportionately wide compared to other predators.
And man are their teeth sharp. Some cultures even used shark teeth as blades in their weapons like here:
Nature can be brutal on blades. Anyone who has ever spent any time outdoors with them will tell you they often break, chip, deform, or otherwise incur damage. If your knives are your teeth, and you reply on them to procure food, you have a serious problem. Some animals have teeth that constantly grow. Sharks have teeth that are not deeply anchored and are readily replaced.
Behavior plays a big roll in a shark’s use of its blades. If every time you went to the kitchen to eat you had to engage in a knock-down drag-out fight most of us would not have survived passed the fifth grade. This is why sharks in nature, and not in movies, tend to be somewhat cautious. They merely have to take a decent bite out of their prey and just let it bleed out. While often overstated and exaggerated, sharks do have an excellent sense of smell. They just track the wounded animal and do not have to risk severe injury.
Anticoagulants in nature are considered venom if they are inside of an animal. Sharks do not have venom because their venom/poison is outside of them. Immersion in water speeds up the process of of bleeding out.
It’s a pretty effective setup. Sharks have been doing it since their have been sharks. Sometimes you don’t need a big knife. Sometimes you just need a bunch of small ones.