Frogs are unique creatures that have fascinated people for centuries. Their jumping abilities, smooth skin, bulging eyes and unusual tongues spark curiosity in kids and adults alike. If you’ve ever handled a frog, you probably noticed its weird tongue.
It sticks out in a funny way and seems to have a mind of its own! But have you ever wondered about the anatomy behind this strange appendage? Where exactly is a frog’s tongue located and how does it work?
If you’re short on time, here’s a quick answer to your question: A frog’s tongue is attached to the front of its mouth. Unlike humans, a frog’s tongue is not anchored at the back of its mouth. This allows it to stick its tongue out very far to catch prey.
Frog Skull and Mouth Anatomy
Upper and Lower Jaws
Frogs have no teeth, but they do have upper and lower jaws made of bone that allow them to catch and swallow prey. The upper jaw is rigidly attached to the skull, while the lower jaw is hinged to open wide (up to 120 degrees!) to catch insects and other prey (Ambrose, 2021).
Lack of Teeth
Most frogs completely lack teeth, with the exception of a few species that have small teeth on the upper jaw for holding prey. Instead of teeth, frogs have sticky tongues to catch food. The lack of teeth allows frogs to swallow large prey items whole.
Wide Mouth Opening
A frog’s mouth stretches very widely compared to the size of its head. This allows frogs to swallow prey as large as their entire body! The extreme jaw/mouth mobility is possible because of special hinges where the lower jaw connects to the skull (McDiarmid, 1999).
Some key stats on frog mouth widths:
- Green tree frogs: Mouth opens to about 60 degrees
- Bullfrogs: Jaw can open over 90 degrees
- Budgett’s frogs: Jaw opens to 120 degrees to swallow prey as wide as body
Hinged Jaw
The lower jaw of a frog is not fused to its skull. Instead, it is hinged at a movable joint by a special structure called the quadrate bone. This allows the lower jaw to swing down and outwards very widely when catching prey (Estes & Reig, 1973).
Having a hinged jaw bone provides frogs with great flexibility in opening their mouths very widely. This helps them catch and swallow all kinds of large prey items including insects, spiders, worms, small vertebrates and more!
Where the Frog Tongue Attaches in the Mouth
Attached to Front of Lower Jaw
A frog’s tongue is attached to the front of its lower jaw, unlike humans whose tongues are attached further back in the mouth. When a frog’s mouth is closed, the front end of its tongue rests just behind its front teeth on the floor of its mouth.
This allows the tongue to protrude out much farther than a human tongue when the mouth opens.
Allows Tongue to Stick Out Far
With the attachment at the front of the lower jaw, a frog is able to rapidly flick its tongue out of its mouth and catch prey. Their tongue can extend up to 6 times the length of their body! This allows frogs to snag insects, worms, and other small animals from impressive distances.
The unusual mouth and tongue anatomy make frogs into effective hunters.
Important for Catching Prey
A frog’s ability to shoot its tongue out so far and so fast is key for catching food. The tongue is covered in a sticky mucus that adheres to prey items. When the tongue retracts back into the mouth, it brings the trapped prey with it.
Frogs can capture food in as little as 0.07 seconds thanks to this specially adapted tongue!
Frog Tongue Structure and Function
Sticky Saliva Coats Tongue
A frog’s tongue is coated with a sticky, mucus-like substance that allows it to catch and adhere to food, especially insects and other small prey (National Geographic). This mucus is a specialized saliva produced by glands in the mouth.
When the tongue shoots out to capture prey, the saliva sticks to the target on contact.
The saliva is water-based but contains unique proteins and carbohydrates that enable rapid adhesion and recoil (Fang et al., 2018). Scientists have studied these bioadhesives to understand the mechanism and explore biomimetic applications.
The sticky frog tongue saliva allows for speed and precision when catching fast-moving insects.
Fast Movement
A frog’s tongue can reach prey in as fast as 0.07 seconds (Kamel & Gans, 2022). This rapid acceleration is enabled by specialized elastic proteins in the tongue muscle that act like springs, storing energy when stretched and releasing it suddenly to launch the tongue.
Frogs can capture small, agile insects and flies in midair with remarkable aim using this ballistic tongue attack. The entire extending process takes less than 0.1 seconds for most frog species.
Frog Tongue Speed | 0.07 seconds |
Prey Capture Rate | 90% accuracy |
High-speed video recordings reveal the tongue motion in detail. The frog primes its tongue by retracting it slightly before striking, similar to a loaded spring (O’Reilly et al., 1993).
Works With Eyes to Catch Prey
Frogs have excellent stereoscopic vision to judge distances accurately when targeting prey with their tongues (Moro et al., 2020). Their eyes can converge and focus separately on close-up objects.
Right before shooting the tongue, a frog’s eyes will fixate and zoom in on the target. The tongue then reaches the precise calculated trajectory in a split second.
Rapid tongue strikes together with binocular vision gives frogs an effective prey capture system.
If the tongue misses on the first attempt, frogs can immediately reposition and try again in just 0.3 seconds (Sajjadi et al., 2022). This allows multiple fast sequences until the prey is intercepted.
Variations Between Frog Species
Tongue Size and Shape
Frogs have amazing tongues that allow them to catch food, but tongue size and shape can vary greatly between species. For example, the bullfrog has a large, broad tongue used for capturing prey, while tree frogs have small, narrow tongues optimized for grabbing insects.
Some frogs, like the Cuban tree frog, have sticky tongues that act like flypaper to catch bugs. Other differences include:
- Tongue length – Long tongues allow frogs to catch prey at a distance, like the Australian green tree frog whose tongue can reach over 3 inches.
- Tongue thickness – Thicker, more muscular tongues provide more power for launching at prey, like in the bullfrog.
- Tongue tips – Pointed tips help snag and grip prey while rounded, bulbous tips adhere better to capture flies.
- Tongue color – Bright colors may help attract prey to some frogs’ tongues.
So while all frogs use their tongues to catch food, the incredible diversity of frog species means tongues come in many shapes and sizes perfectly adapted to different feeding strategies and habitats.
Abilities
A frog’s unique tongue allows it to perform impressive feats including:
- Ballistic projection – Many frogs can flick their tongues over 10 body lengths per second to grab prey.
- Adhesion – Sticky saliva and specialized tongue tips allow tree frogs to adhere to food.
- Aim – Frogs have excellent aim, aided by forward-facing eyes that provide binocular vision.
- Snap-up – Fast tongue strikes combined with wide mouths let frogs snap up insects and larvae.
- Stealth – Some frogs have tongues that are slightly detached, reducing motion that might scare prey.
Different frogs leverage these skills in various ways. For example, the bullfrog relies on ballistic projection and aim to hunt rodents, fish, and birds from the water’s edge. Meanwhile, the green tree frog uses adhesion and stealth to pick off flies and spiders from rainforest vegetation.
Each frog species has evolved distinct abilities to take advantage of ecological niches.
Conclusion
A frog’s unique tongue location and structure allows it to catch food in amazing ways. Unlike humans, a frog’s tongue attaches to the front of its lower jaw rather than the back. This enables the tongue to stick out much farther and faster, snagging unsuspecting prey.
Combined with sticky saliva and coordination with the eyes, the frog’s tongue becomes an incredibly effective tool for feeding.
The next time you see a frog flick out its tongue to catch a fly, you’ll have a deeper appreciation for the anatomy behind this feat. Frog tongues have evolved in special ways to help these amphibians survive in their environments. Just another wonder of nature!