Many owners are fascinated by the possibility that their bearded dragon may actually have a third eye.
As you check over your bearded dragon, all you can see is the regular 2 eyes, so any talk of a third eye is surely just a myth, right? Or is it?
In this post, we will reveal if bearded dragons really do have a third eye? If so exactly where it is, what it’s used for and so much more!
So let’s get into this and learn all there is to know about the bearded dragon third eye!
Read On to Find Out…
Do Bearded Dragons Have a Third Eye?
You’ve probably heard of fish and amphibians possessing a third eye. Frogs, most skinks, and many anoles have third eyes – leftover remnants from their ancestors.
You know your bearded dragon is at least as old in the fossil record as those species, so you’ve probably found yourself wondering:
Do bearded dragons have a third eye? Bearded dragons have a third eye. Referred to as a parietal eye, solar eye, or pineal eye, the third eye serves as a photosensitive organ on your bearded dragon’s head. It connects to the pineal gland, allowing for the biochemical detection of changes in light.
Initially (think back in the prehistoric era), bearded dragons had FOUR “eyes”: their two normal eyes and two parietal eyes.
Over years of evolution, the parietal eyes ended up pushed closer and closer to the middle of the head.
Eventually, the fourth eye became a vestigial organ and fused with its counterpart, creating the third eye beardies utilize today.
Where is a Bearded Dragon’s Third Eye Located?
Before you scare your beardie trying to figure out where this mystical third eye is located, set the poor creature down.
The parietal eye is nothing more than a tiny dot set into the top of your bearded dragon’s head. The third eye sits in the middle of the head, between the two normal eyes.
It’s a different color from the other scales around it, setting it apart most of the time.
However, for reasons we’ll get into later, you’re better off NOT swooping over the top of your beardie to get a glimpse of the third eye. Wait until they’re out and about to take a peek.
Here’s an image that points to where you can find the third eye on a bearded dragon…
Can Bearded Dragons See Out of Their Third Eye?
Now that you know bearded dragons have a unique third eye, you’re probably wondering about the function of this unusual adaptation.
Can bearded dragons see out of the third eye? Bearded dragons can’t see images out of their third eye. Parietal eyes contain a lens, cornea, and retina, but they lack an iris, which is the structure needed to visualize images. Also, the third eye doesn’t connect to the optic nerve, so no imagery is generated in the brain.
The retina and lens are also less developed than in a traditional compound eye.
They detect changes in light beautifully, allowing your bearded dragon to figure out when shadows are passing overhead. (Or when the sun’s going down or coming up) However, that’s where the image processing stops.
They can’t see the shadow’s shape to determine whether it’s you or something more sinister.
And while they understand the sun’s rays change with the seasons, they’re not going to understand the difference between the sun and your UV light.
From what scientists can understand, the parietal eye and organ mediate responses through brain centres, like the hypothalamus, using neural and hormonal systems.
The pineal eye is a primitive structure. It doesn’t function the way a compound eye does. That doesn’t make it less of an exciting adaptation, though.
You just can’t squint into it and expect your beardie to know it’s you.
If you want to find out exactly how bearded dragons see with their regular eyes then check out our easy to follow guide here…
Does a Bearded Dragon’s Third Eye Have an Eyelid?
Based on the primitive nature of the bearded dragon third eye, there’s scientific debate over whether or not to call the pineal eye an eye, officially.
After all, it lacks some critical structures, such as the iris and a connection to the optic nerve.
Which probably has you squinting and wondering, does that third eye have with an eyelid? While covered with a transparent scale, bearded dragons don’t have an eyelid that protects their third eye. The clear scale functions similarly to an eyelid by providing protection from environmental conditions, but there’s no mucus membrane underneath, keeping the cornea moist.
The scale keeps the sensitive structures of the third eye safe from harm. Don’t worry if you touch it – it’s safe enough if you happen to graze it when you pet your beardie.
You should still do your part to protect your beardie, though. Look through their enclosure for any protruding objects.
They may dislodge the scale and cause damage to the parietal eye as your bearded dragon explores.
Also, while the keratin holds up against sand abrasion, your beardie won’t appreciate frequent taps with your fingers to test that it’s still in place. (How’d you like someone continually flicking YOUR eyelid?)
Have you ever wondered if bearded dragons can hear? And if so, how?
Well, why not head over to our new guide that shares all you need to know about how bearded dragons hear…
Do All Bearded Dragons Have a Third Eye?
The pineal eye is an adaptive feature found in all of the cold-blooded lizards, which means that all bearded dragons have a third eye.
The exceptions are the crocodilians, who share a closer ancestry to birds (and, thus, warm-blooded habits). However, that slightly different change in color is difficult to spot in most lizards.
Bearded dragons make it easy. The parietal eye most often appears as a grey spot. If not grey, it’s always enough of a color change to catch your attention.
Oddly enough, humans retain the pineal gland AND a parietal lobe of the brain – though not the pineal eye. Our pineal gland produces melatonin, which aids in our sleep cycles.
And our parietal lobe helps us process sensory information from the world around us. (Which, as you’ll see, are curious parallels to your beardie)
If we had a third or fourth set of eyespots, they regressed inside of the skull distantly in our fossil record. So we missed out on having a third eye of our own.
What is a Bearded Dragon’s Third Eye Used For?
You know your bearded dragon doesn’t use their third eye to see the world around them. At least, not in the way people tend to think of sight.
So what is that parietal eye used for? More than you’d think one tiny spot could manage!
1. Compass Navigation
I know what you’re thinking – bearded dragon navigation? Believe it or not, this is one of the most crucial tasks the parietal eye provides to lizards.
The third eye allows bearded dragons – and other lizards – to get their bearings and figure out how to find their way home.
In 2009, Italy’s University of Ferrara conducted a series of experiments using Italian wall lizards. First, they trained the lizards to navigate through mazes in a swimming pool.
Then they interfered with the third eye in several different ways:
- Artificial day/night cycles
- Paint over the third eye
- Removal of the third eye (yeah, kind of harsh)
Each time, the poor lizards struggled to get through the maze, despite knowing the course.
Only the lizards left in the control group (no change to their third eye) navigated the course without a problem. (While not bearded dragons, the theory is suspected of working with every kind of lizard)
The third eye takes in information on the position of the sun: angle and intensity. It’s not difficult to realize that it would also allow a beardie to find their way home.
2. Predator Avoidance
The third eye can’t form clear images for a bearded dragon to see. However, the rudimentary lens, retina, and cornea CAN detect sudden changes in light and shadow levels.
Add in the third eye’s position at the back of the lizard’s head, and you have a “perfect” early warning system.
While bearded dragons focus on eating, resting, or surveying the area in front of them, the third eye goes to work, observing at the back and above. As soon as the light drops, the beardie knows to head for the hills.
Of course, the system has a few bugs. Since there’s no image, bearded dragons run from EVERYTHING that casts a shadow.
This could mean a falling tree branch (still a potential concern), a robin (probably not a threat), or your hand (which we’ll discuss in a little bit).
Without the iris to focus and clarify the shadow into an image, the bearded dragon’s fight-or-flight reaction takes over. It’s an evolutionary advantage that saw the species through to the modern-day, but it’s not without drawbacks.
The third eye connects directly to the pineal gland in bearded dragons through a small opening in the skull. It also ties into the epithalamus.
Together, the two manage the secretion of melatonin (sound familiar?). Melatonin is a critical component in regulating circadian rhythms.
As cold-blooded animals, beardies need to carefully regulate their activity and rest periods to harbour their resources.
Too much running around, and they’ll end up emaciated and a snack for a predator as they deplete all of their energy stores.
Too much lazing about in the sun, and they won’t get the nutrients they need – not to mention baking themselves alive.
The parietal eye works with the bearded dragon’s body’s biochemical pathways to tell the lizard when to sleep, when to move, and when to eat.
You can find out just how much sleep bearded dragons need in our detailed guide right here…
We get the same information from the pineal gland and epithalamus of our brain. However, our epithalamus doesn’t protrude the way it does in a lizard brain, which is why ours doesn’t work as effectively.
The pineal eye measures light intensity. As such, bearded dragons regulate the amount of time they spend in the sunlight.
Without that third eye, they may turn into dragon jerky out in the desert. It’s a crucial evolutionary advantage that keeps their bodies functioning at the optimum level.
Using the same pathways, the pineal eye also helps with hormone regulation.
The changes in the intensity and angle of the sun tell your beardie when the seasons are changing. This prompts the body to prepare for hibernation.
One little spot helping regulate SO MANY different bodily functions!
Do Bearded Dragons Use Their Third Eye in Captivity?
Happy and content in their enclosure, odds are your bearded dragon isn’t using their third eye as a compass.
However, captive beardies DO use their pineal eye for thermoregulation and predator avoidance, even in a captive setting.
And while you stand in the way of potential predators, if you’re not taking the proper precautions to prevent unnecessary stress in your beardie, YOU might be the biggest predator in their life!
Can I Damage My Bearded Dragon’s Third Eye?
Odds are you won’t damage your bearded dragon’s third eye, even if you happen to touch it.
You SHOULD make sure nothing protrudes into their enclosure, though. Even something with a blunt end could wedge under the clear scale, popping it loose or scratching the cornea beneath.
You also want to practice proper light safety:
1. Measure the distance between your beardie and the UVB lights. The proper distance is 6-12 inches (15.2-30.5cm). Any lower, and you’ll start to cause damage to the delicate eye structures under the protective scale.
2. Only use UVB lights rated for reptiles. Mercury vapor bulbs are much too strong for beardies to handle.
3. Turn the lights out at night. Even if you think a soft red glow is subtle for the evening, the third eye can detect those low light levels. You’ll end up keeping your beardie awake all night, disturbing their wake/sleep cycle.
4. Use Timers to Automate The Day/Night Cycle. It’s vital that your bearded dragon is provided with a natural amount of both day and night time hours each day to ensure that the third eye is stimulated correctly and ultimately to keep your beardie healthy.
You can try and do this manually, although this really isn’t advised as the logistics of turning the light both on and off at the same time each day is difficult, to say the least.
Eventually, busy lifestyles and unforeseen circumstances will mean that the lights will either not be switched on at the correct time or missed completely.
We strongly recommend that you use timers to automate the process.
The best way to do this is to use automatic timers that you can set to control the time that your bearded dragons light turn on and off each day.
This way you can give them the perfect day/night cycle they need and satisfy their biological clock through their third eye.
We have recently reviewed the best timers for bearded dragons and given our opinion on the top 3 we recommend you should use and you can see which ones we have chosen here…
Minimizing Stress in Your Bearded Dragon
Stress is one of the biggest causes of illness and early death in bearded dragons.
How you approach and keep your bearded dragon could directly impact their stress level. Think over what a beardie uses the parietal eye for, and then look at your setup. Could you potentially do better?
You may need to spend a little more, but tanks with front-opening doors are the most friendly and safe for bearded dragons. This allows you to approach your bearded dragon at THEIR eye level, minimizing a fight-or-flight response.
When you have an aquarium or standard terrarium, you’re always reaching in through the top. This means your hand ALWAYS casts a shadow over your beardie, triggering the third eye to react to a predator.
No matter how long you own your beardie, they’ll never get used to the intrusion as you, and they’ll always attempt to run away from the overhead threat.
A tell-tale sign of stress is “stress marks”. You can find out exactly what they look like and the reasons beardies get them in our new bearded dragon stress marks guide…
When holding or handling your dragon, make sure you don’t lean over them. (Remember – shadows equate to trouble for these lizards) Block their faces, so they don’t attempt to squirm away, especially if they’re high off the ground.
If you keep your head tilted back, you won’t block the light entering the third eye, keeping your beardie calm and comfortable.
Bearded dragons retain the evolutionary advantage of a parietal eye. Perhaps captive beardies don’t always need the navigation, and the panic induced by shadows might cause problems for owners keeping beardies in standard tanks.
But if you think through your handling carefully and observe lighting protocols, your bearded dragon will remain happy and stress-free. And you’ll have a chance to brag that you know precisely what that little spot on your lizard’s head represents.
One of the most common questions among new owners and reptile...
Any new or potential owners will naturally want to know if bearded...
Any potential bearded dragon owner will want to know if bearded...