Mechanics of a Cham cleaning their eye

[Brodybreaux25]

So we have all seen our chams cleaning their eyes during a good misting session, it’s even frightened a few of us the first time we saw their eyes temporarily deform while doing it. We have all seen it but how many of us actually understand what is going on there?

Can anyone explain the mechanics behind how chams clean their eyes and turrets?

 

[Brodybreaux25]

What are the major components of a chams eye?

Why does it deform like that?

Is there a membrane between the turret and eyeball that cleans the eye?(like a windshield wiper?)

Is their eyeball round or conical like their turret?

 

[Frigga]

I'd love to hear the answers to these questions! It's so fascinating to watch them cleaning their eyes.

 

[Angelwolf]

Perhaps @ferretinmyshoes could shed a little light on the topic?

 

[Brodybreaux25]

I knew it would be difficult to get informed answers on this topic since it is a pretty advanced subject, hopefully someone steps up!

 

[Brodybreaux25]

No takers?

 

[Brodybreaux25]

Someday someone will answer me, just trying to keep the thread alive at this point...

 

[CamrynTheCham22]

I searched around and couldn't really find much. One of the veterinarians could answer this, but I'm not sure @ferretinmyshoes is active on this forum anymore. What an interesting question, though!

 

[Brodybreaux25]

I’ve found a few threads where other members have posed the same questions too but they never got any answers either...

 

[ferretinmyshoes]

I'm still around! I can't keep up with the daily stuff with a new baby, a toddler, working full time, and all my critters but I do check in from time to time.

Great question! While no one has studied the cleaning of the eye in real time with something like an MRI to see exactly what's going on in there I think I can shed some light based on eye surgeries and necropsies I've performed. The eye ball itself is round for the most part but the iris and part we can see is more conical compared to the rest. There is also a membrane called the third eyelid that humans lack but most other animals tend to have. You've probably seen it on your dog or cat. Interestingly I can't say that I've ever seen it on a necropsy...will have to look for that next time. But I've seen it come up in chameleons enough to believe it's there.

So when they need to clean their eye in their weird way they can basically suck the eyeball deep into the turret and then the third eyelid can elevate to push out debris and cover the opening. Part of the weird movement you see is the eyeball itself rolling around in there too. It's no surprise that a creature with that much voluntary eye movement would be able to do some under eyelid gymnastics as well. And since the little part of the eyeball we can see is more conical it is more obvious when it's moving around and pushing against the skin of the turret from underneath. Rolling around the eyeball against the inside of the turret I imagine it would be to clean off any debris on the cornea and try to dislodge any debris/mucus/etc. Then when they're done all the structures return to their normal place. I might have some gross necropsy pictures of the eyeball if you're interested...

 

[Brodybreaux25]

I'm still around! I can't keep up with the daily stuff with a new baby, a toddler, working full time, and all my critters but I do check in from time to time.

Great question! While no one has studied the cleaning of the eye in real time with something like an MRI to see exactly what's going on in there I think I can shed some light based on eye surgeries and necropsies I've performed. The eye ball itself is round for the most part but the iris and part we can see is more conical compared to the rest. There is also a membrane called the third eyelid that humans lack but most other animals tend to have. You've probably seen it on your dog or cat. Interestingly I can't say that I've ever seen it on a necropsy...will have to look for that next time. But I've seen it come up in chameleons enough to believe it's there.

So when they need to clean their eye in their weird way they can basically suck the eyeball deep into the turret and then the third eyelid can elevate to push out debris and cover the opening. Part of the weird movement you see is the eyeball itself rolling around in there too. It's no surprise that a creature with that much voluntary eye movement would be able to do some under eyelid gymnastics as well. And since the little part of the eyeball we can see is more conical it is more obvious when it's moving around and pushing against the skin of the turret from underneath. Rolling around the eyeball against the inside of the turret I imagine it would be to clean off any debris on the cornea and try to dislodge any debris/mucus/etc. Then when they're done all the structures return to their normal place. I might have some gross necropsy pictures of the eyeball if you're interested...

Very interested! Blood and guts don’t phase me at all!

And thank you for the response, I’ve been wondering about that for as long as I can remember.

 

[ferretinmyshoes]

Ok let me see if I have a good picture

 

[Brodybreaux25]

Something else I’ve always wondered is what kind of joints do chameleons have that allows them to be so flexible? Since every other part of the Cham is so specialized I figured their joints probably are too...

 

[ferretinmyshoes]

I actually had a chameleon necropsy today so got some good pictures! Will post soon.

Something else I’ve always wondered is what kind of joints do chameleons have that allows them to be so flexible? Since every other part of the Cham is so specialized I figured their joints probably are too...

They have regular joints...they are still limited on range of motion of the joints. Elbows have 180 degree range of motion just like ours for example. Still the same bones, probably the same ligaments for the most part. Here's an x-ray to see everything. A little different than ours but overall still mostly the same.

 

[Brodybreaux25]

I actually had a chameleon necropsy today so got some good pictures! Will post soon.



They have regular joints...they are still limited on range of motion of the joints. Elbows have 180 degree range of motion just like ours for example. Still the same bones, probably the same ligaments for the most part. Here's an x-ray to see everything. A little different than ours but overall still mostly the same.

That’s awesome, thank you so much. Can’t wait to see the pics!

 

[ferretinmyshoes]

So this poor panther girl died due to follicular stasis, not eye related issues. But we can learn from her nonetheless.

Before

This is just to show that the eyelid is not really attached to the bulb very well, which is why they are able to move it around so much when cleaning.

This is how big the eyeball itself is. Just a linear cut made horizontally through the skin of the turret.

Here you can see the membrane that is the third eyelid. It’s very thin because all these structures are very small and delicate.

Here you can see some of the muscles of the eye that allow it to move so much both in normal movement and when cleaning.

This is the eyeball by itself to show the shape and how the part we can see is more conical than the rest.

 

[Brodybreaux25]

So the part that’s streatched out here, is that the membrane? And how does that clean the eye? Float between the eye and turret and act as a windshield wiper? Does it move over the eye from side to side or does the eyeball move while the membrane stays stationary?

 

[Brodybreaux25]

So cool how the eye is both spherical and conical. What is the reason the pupil is conical? What advantage does this give the Cham?

 

[Lennoncham]

So this poor panther girl died due to follicular stasis, not eye related issues. But we can learn from her nonetheless.View attachment 212415
Before

View attachment 212416
This is just to show that the eyelid is not really attached to the bulb very well, which is why they are able to move it around so much when cleaning.

View attachment 212417
This is how big the eyeball itself is. Just a linear cut made horizontally through the skin of the turret.

View attachment 212418
Here you can see the membrane that is the third eyelid. It’s very thin because all these structures are very small and delicate.

View attachment 212420
Here you can see some of the muscles of the eye that allow it to move so much both in normal movement and when cleaning.

View attachment 212419
This is the eyeball by itself to show the shape and how the part we can see is more conical than the rest.

That is interesting and slightly disturbing lol. Do chameleons not have blood vessels in there eyes? Just ask cause it’s all white.

 

[Brodybreaux25]

That is interesting and slightly disturbing lol. Do chameleons not have blood vessels in there eyes? Just ask cause it’s all white.

It’s dead, blood probably pooled...