Boa constrictors may not have fangs like venomous snakes, but their backward-curving teeth serve an important purpose for these non-venomous yet powerful constrictors. If you’ve ever wondered why boas have so many teeth or what those teeth are used for, read on to uncover the details behind the boa’s formidable grin.
If you’re short on time, here’s a quick answer: Boa constrictors have around 100-120 sharp, backward-curving teeth designed to grip slippery prey like birds, bats, and rodents to prevent escape once the snake strikes and starts to constrict.
Boa Constrictors Have Plenty of Teeth
Boa constrictors, like all snakes, have a mouth full of razor-sharp teeth that they use to grab and hold prey. Here’s a closer look at a boa’s formidable choppers:
Around 100-120 Total Teeth
Boa constrictors have between 100-120 total teeth, with about 20-30 teeth on each side of the upper jaw and 10-20 on either side of the lower jaw. The number of teeth can vary a bit depending on the exact species and subspecies of boa.
Unlike humans, boas don’t use their teeth for chewing. Instead, they use their teeth like fish hooks to snag prey and prevent it from escaping their clutches. Once a boa grabs hold with its teeth, it coils its muscular body around the prey and constricts to suffocate it.
Teeth are Regularly Replaced Throughout a Boa’s Life
A boa constrictor’s teeth are regularly lost and replaced throughout its lifetime. Baby boas are actually born without any teeth at all! Their first set begins to emerge within a day or two after hatching.
From then on, boas go through a continuous cycle of losing old teeth and growing new ones to take their place. Unlike humans who have just two sets of teeth over a lifetime, boas can regenerate replacement teeth indefinitely.
This tooth replacement cycle allows a boa to maintain a full set of sharp, functional teeth essential for grasping prey and defending itself. Worn or broken teeth get replaced by fresh new choppers.
A boa’s tooth replacement process is quite rapid. Within as little as 24 hours, an old tooth can be pushed out and a new one emerge in its place. This ensures the snake almost always has a complete set of teeth ready for hunting.
Their Teeth Point Backwards
One of the most intriguing aspects of boa constrictors is their unique teeth. While they may appear harmless at first glance, boa constrictors actually have rows of razor-sharp teeth that curve backwards into their mouths (https://reptile.guide/boa-constrictor/).
This special tooth configuration serves two important purposes for these efficient predators.
Backward Curve Helps Grip Prey
A boa constrictor’s backward-curving teeth function like fishhooks, allowing them to snag prey and prevent escape. Once they strike, their prey has little chance to wiggle free from their vice-like grip.
Researchers have found that the teeth can exert pressure exceeding 27 kilograms per square centimeter, which is over 5 times the bite force of an adult lion (https://www.nationalgeographic.com/animals/article/snakes-have-been-around-for-nearly-139-million-years).
So if you ever come face-to-face with one of these snakes, don’t expect to easily pull away once those teeth puncture your skin!
Prevents Prey Escape Once Constriction Begins
In addition to securing prey, the backward curve of boa constrictor teeth also serves another critical purpose – preventing escape once constriction begins. As these muscular snakes begin to wrap their bodies around captured prey, the teeth act like hooks that sink deeper with any attempt by the prey animal to struggle free.
This allows the boa to fully constrict without interruption in order to subdue and swallow animals nearly as wide as they are.
Research by herpetologists has shown that attempts to resist constriction are futile once in the grasp of a boa. In fact, such resistance can actually hasten demise by stimulating increased constriction force.
So whether rodent, bird, deer or other prey, death comes quickly and inevitably courtesy of the boa’s ruthless dentition and powerful body.
Boa Teeth Help Grip Slippery Prey
Birds, bats, and rodents are common prey
Boa constrictors are non-venomous snakes found in the Americas that are known for their method of subduing prey—constriction. Their diets consist primarily of birds, bats and small mammals such as rodents. When hunting, boas rely on their excellent sense of smell to track down potential prey.
Once targeted, they strike quickly to seize the animal in their jaws.
Birds, bats and rodents all represent slippery prey for boa constrictors. Feathers and fur do not provide much traction against the boa’s skin. However, the backward-curving teeth of boa constrictors allow them to establish an extremely secure grip on prey.
Smooth feathers and fur resist side-to-side grip
The feathers of birds and the fur of bats and rodents create smooth, slippery surfaces. While scales may provide traction against forward and backward motion, feathers and fur do not grip well from side to side. This makes it difficult for boas to hold onto prey.
However, the specialized teeth of boa constrictors counteract the slippery nature of feathers and fur. Their teeth point backward, toward the rear of the mouth. When prey attempts to slide forward or backward, these rear-angled teeth act like barbs against a fish hook, preventing escape.
In addition, each side of a boa’s upper jaw has 5-9 rows of these hooked teeth. When the boa bites down, the teeth become embedded in the feathers or fur. Even if prey shifts from side to side, the rows of teeth maintain a secure grip.
So while birds, bats and rodents have evolved smooth coverings that enhance their mobility, boa constrictors possess uniquely shaped teeth that allow them to seize and hold these slippery prey animals.
Teeth Anchor the Snakes’ Jaws
A boa constrictor’s flexible jaws allow it to swallow prey much larger than its head, but this flexibility comes at a cost. Without a rigid jaw structure, the lower jaw would be prone to dislocation when opening wide or constricting large struggling prey. This is where the boa’s teeth come in handy!
Jaws can fully open to swallow large prey whole
A boa constrictor’s lower jaw contains around 100 small, angled, needle-sharp teeth that point backwards. These teeth act like anchors, preventing the lower jaw from being pulled out of alignment when the snake opens its mouth wide enough to swallow large prey whole.
For example, boas have been documented swallowing prey up to 11 times their own body weight – try doing that with a dislocated jaw!
The boa’s stretchy ligaments allow the left and right sides of the jaws to operate independently from each other. This means one side can stay firmly anchored with teeth while the other side extends outward to envelop the prey item. Quite handy when your dinner is bigger around than you are!
Teeth prevent dislocation of flexible lower jaws
In addition to anchoring the jaws when swallowing, the rows of small recurved teeth also prevent dislocation of the lower jaw while the snake is constricting its prey. As the snake coils its muscular body tightly around the victim, the struggling prey attempts to pull the snake’s jaws apart.
But the angled teeth dig in, acting like barbs on a fishing hook, preventing the flexible lower jaw from being ripped out of place.
While a dislocated human jaw is merely uncomfortable, a dislocated snake jaw could be life-threatening. If a constricting boa lost its grip during the violent death throes of large prey like a caiman or jaguar, that prey could easily turn the tables and kill the snake.
Boas’ sturdy teeth help avoid this grisly fate!
Fangs vs Teeth: Different Tools for Different Snake Lifestyles
Venomous snakes have hollow fangs to inject venom
Venomous snakes like cobras, rattlesnakes, and coral snakes have specialized teeth called fangs that are used to inject venom into their prey. Fangs are located at the front of the mouth and connect to venom glands behind the eyes.
When a venomous snake bites, muscles squeeze the venom glands to force venom through the fangs into the prey. Fangs are hollow and needle-like, perfect for piercing skin and injecting venom deep into tissues. They work like hypodermic needles!
Most venomous snakes have hinged fangs that lie flat against the roof of the mouth when not in use. When the snake opens its mouth to bite, the fangs swing down into a “ready to inject” position. A few species like coral snakes have fixed fangs that are always erect.
Venom injection is extremely quick and efficient with this fang system, allowing venomous snakes to rapidly immobilize prey.
While all snakes regularly shed their skin, venomous snakes also regularly shed and replace their fangs. New fangs grow to replace old and worn ones, ensuring that venom can keep flowing. Fangs are a highly adapted, specialized tool for a venomous snake’s survival.
Constrictors rely on strength instead of venom
In contrast to venomous snakes, nonvenomous snakes like boa constrictors and pythons have rows of curved, pointed teeth along the upper and lower jaw. These teeth are not hollow or connected to venom glands. Instead, their purpose is simply to seize and grip prey in preparation for constriction.
When constrictors strike, these multiple rows of teeth allow them to get an extremely solid hold on prey. The inward pointing tips prevent struggling prey from easily escaping their clutches. Constrictors like boa constrictors and pythons then wrap their muscular bodies around prey and squeeze tightly to suffocate it.
While boas and pythons could seriously injure or kill prey with their bite, they lack venom and instead rely on their massive strength and bulk for hunting success. Accordingly, their teeth do not need to inject toxins but simply need to latch on firmly.
Constrictors also regularly replace their teeth just like other snakes.
Conclusion
A boa constrictor’s mouthful of backward-slanted teeth may look scary, but these reptiles use their teeth solely to capture and consume prey, not to inject venom. Their numerous teeth enable boas to seize slippery meals like birds and bats so they can constrict and swallow their food whole.
So while startling at first glance, the boa’s grin reveals an effective adaptation to its predatory lifestyle.
