There are a lot of incredible teeth in the animal kingdom. Sharks have multiple sets of teeth and are constantly replacing them, while some animals (like anteaters and pangolins) have no teeth at all.
But, what are some animals with the strongest teeth?
Sea snails have the strongest teeth and their teeth are actually harder than any other biological material. Some other animals with hard teeth include mice and rats, beavers, parrotfish, ants, and sea otters. The structure of a tooth and how the enamel is distributed on the tooth’s surface affect how strong or weak it is.
Below, we’ll take a closer look at these animals with strong teeth, as well as how hard their teeth are, and what they use them for.
While land snails are associated with slithering like a snake and munching on plants and lettuce in the garden, sea snails are known for their incredibly strong teeth. In fact, a sea snail (or limpet) has teeth made up of the hardest known naturally occurring substance in the world.
Marine snails’ teeth are stronger than spider silk, which was previously the hardest known biological substance, biological meaning that it was not made by man. According to research, snail teeth are made of goethite nanofibers encased in protein. Goethite is a type of iron-containing crystal.
Sea snail teeth have measured strength between 3 and 6.5 gigapascals (that’s 3 billion-6.5 billion pascals). For reference, the other strongest biological substance, spider silk, is about 1.3 gigapascals. Spider silk is strong enough to make kevlar for bulletproof vests.
Sea snails need their strong teeth because they use them to scrape bits of algae off rocks for food. Their teeth are so strong that it’s not uncommon for them to break parts of the rock off, too.
Something else interesting about snail teeth is that they have a lot of them. Marine snails and garden snails belong to the mollusk family. Snail species have thousands of microscopic teeth in their mouths, with the number varying per species.
Interestingly, snail teeth don’t necessarily erupt from the gumline. Instead, many of their teeth are located on their tongue, which they use to mash food. The tooth-covered tongue is called a radula.
Mice and Rats
Even though the enamel of mice and rats is only 5.5 on the Mohs hardness scale, it’s the structure that makes them so incredibly strong. Their enamel is a criss-cross pattern of calcium hydroxyapatite that’s embedded in collagen.
Mice and rats can chew through a lot of harder materials. Even though their teeth are only a little bit harder than humans (which are a 5 on the Mohs scale), their jaw strength paired with the unique structure of their teeth lets them chew through all sorts of things including wood, plastic, rubber, and even softer metals like aluminum.
Even though their gnawing behavior might seem like a nuisance to us, it’s actually pretty important for mice and rats to wear down their teeth. Their teeth never stop growing and if left unchecked, they would become overgrown. Overgrown teeth would be very problematic, as they’d interrupt the rodent’s ability to chew and eat.
Beavers are another rodent known for the hardness of their teeth. And, they need them to be. Beavers use their teeth for stripping away hard tree bark and have even been known to eat through entire trees.
If you’ve ever seen beaver teeth either in photos or in the wild, you also may have noticed their orange color. A beaver’s teeth are orange because the enamel that covers their teeth contains iron. The iron in their teeth contributes to how hard they are.
This iron-fortified enamel is pretty important because the inside of the beaver’s teeth is made from dentine. The dentine is softer than the enamel and that causes their teeth to wear down unevenly. This actually becomes an advantage because the uneven wear makes their teeth sharper and better suited for eating through trees and bark.
Because beaver teeth wear down like this, they also never stop growing. In fact, beaver teeth grow an average of 4 inches every year.
Parrotfish are big, bright fish that frequent tropical waters. They spend most of their day chewing on hard coral, breaking it off into pieces, and eating both the hard skeleton and the softer algae and organisms that make up the coral.
Parrotfish teeth are ranked about 5 on the Mohs scale and are stronger than copper, gold, and silver. They are made up of a strong biomaterial called fluorapatite, which contains the minerals fluorine, calcium, phosphorus, and oxygen. Additionally, parrotfish teeth have a crystalline structure that makes them even stronger.
Despite their strength, hard coral is a pretty tough material. It would have to be to break a parrotfish tooth. One square inch of their teeth can tolerate about 530 pounds of pressure, which is the same pressure created by the weight of 88 elephants.
Fortunately, when parrotfish teeth break off, they have more. They have about 1,000 teeth arranged in 15 rows that get pushed forward as they break them.
Ants are pretty incredible when you consider that they might be able to lift as much as 5000 times their own body weight and they survive floods by linking together to float on water. They also have really strong teeth.
Ants have mandibles, which are teeth that protrude out of the mouth. They use their mandibles for just about everything, as they’re the human equivalent of hands. This includes catching prey, fighting, cutting leaves and food, brood care, and communication.
Researchers at the University of Oregon recently published their findings on the makeup of an ant’s incredibly strong teeth, with a focus on the leafcutter ant, as well as other animals with similar tools like spiders, scorpions, and Nereid worms.
The primary material of an ant’s teeth is the same as its exoskeleton and about as strong as plastic. That being said, their mandibles also contain 16% zinc in addition to the materials of their exoskeleton. This makes them as strong as aluminum and much harder than their teeth would be without zinc.
The same study found 20% zinc in scorpion stingers. Zinc helps by making the stinger (in the case of the scorpion) or the mandibles (in the case of the ant) significantly stiffer, so they don’t have to work as hard to pierce the skin or cut into plant matter.
Sea otters eat a varied marine diet, but they are known for munching on hard-shelled mollusks like mussels and clams. While sea otters use rocks to help break open mollusk shells, then they finish breaking them open using their teeth.
Sea otters would need to have hard teeth to prevent them from chipping, particularly when you consider their diet. As it turns out, their teeth are about 2.5 times as strong as the average human’s teeth.
Sea otters’ teeth are strong because they have multiple layers of enamel on their teeth. Scientists have compared them to the teeth of early humans, which were significantly harder than those of modern-day humans and less likely to chip.
How Is an Animal’s Teeth Strength Measured?
The hardness or strength of something is measured using pascals, which is a unit of pressure or tensile strength. Essentially, animals with strong teeth can withstand a certain amount of stress depending on how strong they are.
Often, the strength of an animal tooth is measured in pascals. Pascals are used to measure stress and pressure. A megapascal is 1 million pascals, while a gigapascal is 1 billion pascals.
The strength of teeth can also be measured on Mohs scale, which is used to test the hardness of various minerals by scratching them against one another.
Minerals are rated from 1 to 10 on the scale, with diamonds being the hardest known mineral. For reference, human tooth enamel has a hardness of 5 on Mohs scale and dentin (the soft part of teeth) has a hardness of 3.
How Does Measuring Animals With the Hardest Teeth Benefit People?
Researchers spend a lot of time studying the animal kingdom because it’s hard to know when something can be applied in a way that would benefit the human race.
For example, spider silk is incredibly strong. So strong, in fact, that lab-made spider silk is used in the production of Kevlar, the same material used to make bulletproof vests.
Tooth strength is measured for the same reason. In addition to natural human curiosity and wanting to learn, there may be scientific applications for material modeled after a marine snail’s teeth. For example, it may be used to make better dental fillings or harder drill bits.
What Animal Has the Strongest Teeth in the World?
Limpets (or sea snails) have the strongest teeth in the world. In fact, snail teeth are so strong that they often break off bits of rocks when they are eating algae off the rocks underwater.
While they are not as strong as lab-created diamonds, which withstand the pressure of up to 2 million megapascals according to a recent study published in Nature, the material a sea snail’s teeth are made out of is the hardest biological substance that has been discovered so far.
Were you surprised to learn that sea snails have the hardest, strongest teeth in the world? Some other animals with the strongest teeth include mice and rats, beavers, parrotfish, ants, and sea otters.
Researchers study tooth strength for a lot of reasons, from dental to manufacturing applications. Regardless of the why, I do find animal teeth interesting to learn about. Hopefully, you’ve enjoyed it, too!