Animals With The Most Teeth (Explained By Zoologist)

snail with many many teeth

Teeth are one of the body’s most valuable assists.

They are responsible for catching food, breaking down food, aiding in communication and changing the structure of the face.

When we think of teeth, a grinning chimp or a hungry crocodile may come to mind.

But, in the Animal Kingdom, these organisms have a puny amount of teeth.

There are some organisms roaming our planet with a mouth full of thousands of teeth! So what animals have the most teeth?

Surprisingly, the small umbrella slug has more than 750,000 teeth which makes it the clear winner for the species with the most teeth. Garden snails also have an impressive number of teeth in the thousands and then there’s the lamprey with hundred of teeth or the frilled shark with as many as 300 teeth. 

Let’s take a closer look at these toothy animals and learn what they use all those teeth for!

What (Exactly) Is A Tooth?

Wait, wait, wait.

Before we get started, let’s firstly remind ourselves what a tooth is.

No, this isn’t a trick question. I know you know what a tooth is. You look in the mirror, and you brush your teeth (I hope). We have all, at one point or another, seen those pearly whites.

You may even have pets and know what their teeth look like.

However, not every tooth in the Animal Kingdom looks the same. In fact, not every tooth holds the same function.

For the purpose of this article, we are defining the term “tooth” as a hard or resistant structure that can be found in the jaws, or around the mouth and pharynx – the oral and nasal cavities that lead from the head to the oesophagus –  of vertebrates.

Read on to discover the animals that have the most gnashers in their mouths.

1. Umbrella Slug

A slug?! With teeth?! Have I gone mad?

One of the biggest take away messages from my time studying animals is to expect the unexpected. And that is especially the case for the umbrella slug, which steals the top spot for the most amount of teeth in the Animal Kingdom.

The umbrella slug is a species of marine gastropod, native to the Indo-West Pacific.

Now, unlike you and I, the umbrella slug has a more unconventional set of teeth in the form of a radula – a tongue-like structure that contains thousands of microscopic teeth.

But just how many thousands?

It may come as a shock that, throughout its lifetime, an umbrella slug can get through an impressive 750,000 teeth. I’m not quite sure which crazy scientist sat down and counted this, but hey, each to their own.

The tooth-laden radula scrapes organic matter, from algae and sponges, to other gastropods, in which the umbrella slug feasts upon. Over time, the teeth-like structures get worn down and replaced in an efficient tooth conveyor belt.

2. Garden Snail

From sea to land, the next contender on the list puts our measly 32 human teeth to shame: The common garden snail.

You may have noticed these slow moving molluscs after a rain shower, but have you ever stopped and given them any time of day?

Probably not.

But, get the microscope out and a world of hideous monstrosities reveal themselves.

Similar to their oceanic cousins, the umbrella slugs, common garden snails have radulas adorned with up to 14,000 microscopic teeth.

These “teeth” are not teeth as we know. Instead, they are referred to as denticles.

These teeth are primarily composed of chitin – the same material that makes up our fingernails, or the exoskeleton of beetles – which is incredibly durable and tough. Under the microscope, rows of razor-sharp spikes can give any medieval torture device a run for its money.

Luckily for us, garden snails have a preference for organic garden waste and fresh veggies.

However, there are some snails, such as the giant Powelliphanta snail, that use their sharp radula’s to devour earthworms and slugs. Although the size of a human fist, the Powelliphanta snails have just 6,000 teeth on their radula – still considerably more than the average human mouth.

3. Frilled Shark

We’re heading back into the inky depths of the ocean for our next contender.

As you descend into the ocean abyss, you will most likely stumble across weird, alien-like species. However, none are as weird as the frilled shark.

Found lurking at depths of up to 1,500 meters, frilled sharks look like they’ve come straight out of a nightmare. Their serpentine-like, frilly body and large, cloudy eyes are enough to send shivers down anyone’s spine.

However, their external appearance is a fairy tail compared to what lurks within their mouth.

On both the lower and upper jaws, between 20 – 30 rows of teeth can be found. In total, a frilled shark can have as many as 300 needle-sharp teeth in its jaw.

As with many shark species, frilled sharks constantly lose and regrow rows of teeth throughout their lifetime.

The rows of teeth are found in vertical sets, starting from the outer lip and going inwards. Not only does this allow for the frilled shark to tear and slice its prey, but it also ensures that prey can’t escape.

Each individual tooth is formed with a central cusp with two cusplets either side, forming a trident-like shape. The increased surface area of each tooth can deliver shockingly effective slices and gashes in prey species, such as cephalopods (squid and octopuses) and other fish species.

Still, not much is known about frilled sharks. However, ongoing research is delving into this elusive animal.

New findings may suggest that frilled sharks may use their rows of teeth to trick their cephalopod prey into entangling themselves.

“No wonder squids end up as easy prey for the frilled shark”, I hear you mutter to yourself.

Well, cut the squid some slack. In the black ocean void, the white teeth of the frilled shark stand out like a sore thumb, causing the cephalopods to become curious. After all, food in the abyssal zone is hard to come by. This is when the frilled shark strikes with those needle-like weapons.

4. Lamprey

We’re sticking, quite literally, to the nightmare realm for this next animal.

Meet the lamprey – a primitive, eel-like fish. This is one unusual animal, but you would be forgiven if you have not heard of it before.

Across the globe, there are 31 different species of lamprey, found in both fresh and saltwater.

As juveniles, most lamprey species feed on detritus that has accumulated on the ocean or lake floor. However, as they mature, lampreys undergo a drastic morphological change, referred to as metamorphosis.

This metamorphosis is triggered by a need to shift their diet from detritus to animal protein. And lampreys have a pretty gruesome way of doing this.

They develop a suctorial disk. This is a fancy science term to refer to a mouth that is used for attaching to other animals.

As adults, lampreys are parasitic. They attach and stick to host fish using this specialized disk and suck blood and bodily fluid.

This is made possible by the 100 sharp teeth found within the circular suctorial disk. Almost like a giant leech. Shudder.

The teeth serve various functions.

Outer teeth on the disk, known as circumoral teeth, embed into the flesh of their prey host. This locks the lamprey in place and becomes near impossible for the host to dislodge it.

Within their mouth, they also have a tongue-like structure known as a piston. Similar to the radula of gastropods, the lamprey piston houses many small, sharp teeth-like structures that gouge away at the flesh of its host. And voila, that’s how the lamprey feeds. Delicious.

5. Catfish

On first impressions, catfish appear to look as if they’ve forgotten to put their dentures in.

Their large, gaping mouths show no visible signs of teeth.

However, peer in closer to the mouth of a catfish, and thousands of miniscule teeth reveal themselves. These, like the teeth of so many other animals on this list, are not the traditional teeth that us humans are accustomed to.

Known as cardiform teeth, the teeth of catfish are small and arranged in multiple rows. Cardiform teeth are not as sharp as other teeth, such as the canines of other, typical predators. Instead, they resemble the tips of a stiff brush and have a texture similar to sandpaper.

The texture of a catfish’s teeth have been compared to that of the tongue of a house cat.

Some species of catfish can have as many as 9,ooo cardiform teeth that extend into the roof of its mouth and down its throat. However, most species of catfish, such as the Striped Rapheal catfish, have just a couple of hundred cordiform teeth. Still, plenty more than us humans.

6. Giant Armadillo

For this next animal, we’re leaving the water altogether and venturing to the grasslands of South America.

The giant armadillo is somewhat an anomaly on this list. All the other species we’ve discussed either live in the water or are a mollusk.

The armadillo is neither a mollusc, nor does it live in the water. It is a mammal that feeds primarily off ants and termites.

As a group, mammals are not known for having a lot of teeth. The armadillo, however, breaks barriers.

While they may not have as many teeth as other species in the world, they deserve a place on this list as they have the most teeth of any terrestrial mammal known to science.

Giant armadillos can have between 70 – 100 peg-like teeth. Compare that to our own measly 32, and this seems like a lot.

But why do these animals have so many?

Well, unlike most other mammal species, which have heterodont teeth, armadillos are homodonts.

Let’s break for a quick-fire biology lesson on the differences between heterodonts and homodonts. Heterodonts have complex teeth, with multiple different shapes and sizes that interact with food differently. They tear, grind and mash a variety of textures to get the maximum nutrients available out of their food.

Homodonts, on the other hand, have very simple teeth. There is no variation in the type of tooth and very slight differences in the size.

This, coupled with a long snout, means armadillos can pack a lot of these small peg teeth into their mouth which is used for crushing their small invertebrate prey.

The teeth of a giant armadillo are also referred to as hypselodont. This means they continue to grow throughout the lifetime of an armadillo. They are also shallow-rooted and lack enamel.

But hey, with a diet of just ants and termites, who needs super complex teeth. Certainly not the giant aramdillo.

Closing Thoughts

If you thought all teeth were the same, oh how wrong were you.

Teeth have evolved over millions of years to carry out a wide range of functions, from grazing to crushing.

From miniscule molluscs to parasitic fish, each animal has evolved ways to best utilize their mouthful of gnashers – whether it’s a few hundred, or hundreds of thousands.

Teeth can be simple or complex, and yield many surprises.

So, the next time you stare at a simple garden snail, be grateful that they are the size they are. Afterall, you wouldn’t want a bear-sized snail, with 14,000+ teeth, living in the back of your garden.

Leave a Comment

Your email address will not be published. Required fields are marked *