Sloths have been depicted as the slowest moving mammals in the world, and have been stuck with that reputation. However, sloths are amazing mammals. They may seem innocent and defenseless, but sloths have sharp claws that can scare off predators. Sloth teeth have a unique structure that is also a good weapon for self-defense.
Sloths are strong, possessing highly-specialized muscles that help them easily lift their entire body weight with just one arm. They may be slow on land, but they are actually three times faster in water than they are on trees!
Sloths move slowly because of their incredibly slow metabolic rate. This makes the digestion of even a single leaf take about 30 days. Sloths are nothing but peculiar – from their distinct appearance, anatomy and metabolism, down to their teeth, sloths are undoubtedly interesting.
Do Sloths Have Teeth?
Even though sloths don’t usually open their mouths wide enough to show their teeth, sloths do have teeth, and they are sharp. However, sloth teeth are peculiar as well and differ from most mammals’ dental structures.
Sloths have a few teeth as they do not possess incisors or canines. What they do have are upper and lower molars that help them crush their food. These teeth are high-crowned and have open roots, enabling continuous growth throughout a sloth’s life. Despite the lack of incisor teeth and canine teeth, sloths have two pairs of prominent razor-sharp fangs that are called “pseudo-canines”. These pseudo-canines are used to help sloths cut and bite off their food from trees.
Pseudo-canines are located at a sloth’s upper and lower jaw. The upper fangs are slightly located in front of the lower fangs. This causes a mild overbite which makes the two pairs of pseudo-canines constantly grind against each other. As a result, each time sloths open and close their mouths to eat, the pseudo-canines inevitably rub against each other, keeping the fangs incredibly sharp.
How Many Teeth Do Sloths Have?
Sloths have a total of 18 teeth. Unlike most mammals, a sloth’s mouth is composed of only two types of teeth –4 pseudo-canines, located on the top and bottom mandible, and 10 molars in the upper jaw directly grinding against the 8 molars on the lower jaw.
The pseudo-canines are located at the front part of the sloth’s mouth and are often mistaken as their front teeth. These caniniform teeth are also separated from the rest of the molars by a huge gap also found in other mammals, called diastema.
Sloths are generally peculiar, and their dental structure is no exception. Like horses and rabbits, sloths are hypsodonts, which means their teeth have open roots that allow them to continuously grow throughout their lives.
Why Do Sloths Have Blackened Teeth?
The prominent fangs that are often seen at the entrance of a sloth’s mouth are usually black-hued, which is caused by their specific diet. As herbivores, sloths feed mainly on leaves, from which they often ingest tannins. Tannins are biomolecules that provide dead leaves with their brown color. Unlike most mammals, sloths do not have a protective layer of enamel coating their teeth, which makes tannins easier to affect them.
The high amount of tannins in a sloth’s mouth can turn its fangs black. However, the pseudo-canines at the lower jaw usually do not change in hue as they are constantly rubbing against the upper fangs.
Do Sloths Have Baby Teeth?
Unlike most diphyodont mammals, such as dogs, humans, and sheep, sloths are not born with a deciduous set of teeth or baby teeth. Instead, sloths are born with a fully-formed set of teeth that continuously grow throughout their lifetime.
What Are Sloth Teeth Made Of?
Instead of enamel, sloth teeth are made up of two types of dentine and an outer coating of cementum, with the softer dentine comprising the tooth’s innermost region. These two types of dentine wear at different rates. When sloth teeth emerge, they are simple and cylindrical, lacking the cusps and basins typically found in mammalian teeth.
Are Sloth Teeth Sharp?
Sloths may be slow mammals, and their slow movement can be predator magnet factors, but these mammals are not as defenseless as many think. They have sharp pseudo-canines that are not only used in cutting and nipping leaves from trees, but are also utilized when fighting predators.
Sloths also possess sharp curved claws that help them climb trees. These claws can grow between 3 to 4 inches or 8 to 10 centimeters in length and can be dangerous when used against predators.
Sloth claws resemble oversized nails, but they are made up of lengthened and curved distal phalange bone fragments that protrude from the sloth’s limbs. A sheath of keratin, the same substance that covers our fingernails and hair, protects these bones.
What Do Sloths Use Their Teeth For?
The two fangs or pseudo-canines in front of a sloth’s jaws are specifically built for nipping and biting off leaves from trees. The remaining cheek teeth, on the other hand, are merely molars with identical appearance and structure and are specifically designed for crushing and grinding plant materials.
Their sharp teeth are also used when fighting off predators. Since they wouldn’t always be able to run and escape hunters, their nails and razor-sharp fangs come in handy.
Do Sloths Bite?
If sloths are left alone in their natural habitat, they pose no threat to humans. However, once sloths feel they are being threatened or attacked in any way, they can lash out using their claws and can bite people. When sloths become enraged, they bite regardless of whether it is another sloth, a predator, or a gentle human attempting to interact with them.
A sloth’s bite is usually not poisonous, but it can be painful and can carry harmful infections. Sloth fur can also carry insects such as mosquitoes, which can transmit diseases.
The photo featured at the top of this post is © Janossy Gergely/Shutterstock.com
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