Eclipse/Shatter/Marble Eyes: What causes it?

[KelliH]

Ok so we all know that the Eclipse eye trait can be made from scratch with Patternless Stripe breeding. That being sadi, do you guys have any theories as to what is actually going on physically with the eye? It's obviously a genetic flaw of some sort, but I've always wondered what it is biologically that causes this anomaly. What would the scientific term for it be? Any thoughts or ideas?

 

[robin]

closest i can think of just by looking is a detatched retina. i am sure it isnt that but it looks similar.

also sometimes dogs have two different colored eyes or one eye with two colors. i have seen that in ausies.

 

[Retribution Reptiles]

Well when viewing the eye closely you can clearly see a pupil.

http://en.wikipedia.org/wiki/Eye_color

the first paragraph was quite interesting. But then again if the eclipse is a true recessive why can you create it from non eclipse lined lineage? Possibly we have been duped all these years?

 

[Gecko Gallery]

And if it can "fade" or change, what's up with THAT aspect of this eye anomaly?

 

[justindh1]

There's some interesting stuff that could explain the eclipse as bit better in the link you posted Ryan. This makes me wonder whether the eclipse genetics affect the pupil or the iris?

Heterochromia (also known as a heterochromia iridis or heterochromia iridium) is an ocular condition in which one iris is a different color from the other iris (complete heterochromia), or where the part of one iris is a different color from the remainder (partial heterochromia or sectoral heterochromia). It is a result of the relative excess or lack of pigment within an iris or part of an iris, which may be inherited or acquired by disease or injury. This uncommon condition usually results due to uneven melanin content. A number of causes are responsible, including genetic, such as chimerism, Horners Syndrome and Waardenburg syndrome.

 

[MiamiLeos]

I feel that it is a failure of all or some of the iris pigment to develop, making the iris appear clear and showing the pupil color (red or black) through the iris.

 

[KelliH]

I feel that it is a failure of all or some of the iris pigment to develop, making the iris appear clear and showing the pupil color (red or black) through the iris.

This is what I've been leaning towards also. However I have noticed on some Eclipses that you can see a red pupil underneath the black eclipse eye. It could just be some weird reflection caused by the flash. Here's what I mean.

 

[Enigmatic_Reptiles]

This brings up a point I have considered before as well. I was thinking the same thing as Bridgette and Kelli. I have noticed the "pupil" in images before but have you ever seen any variation in the "pupil" size? I have never seen the red either dilated or constricted. It always appears to be roughly the same size...which makes me think it is a reflection of some sort.

 

[LZRDGRL]

Someone else has posted once that this red slit in the pupil is a reflection of your flash, just like people get red eyes on a photo. Don't know if this is true, but it sounds plausible.

Chrissy

 

[KelliH]

I wish the eyes really looked like that (the red slit of a pupil)!

 

[geckogirl3]

so do i

 

[Pico]

As i knw black eclipse eye might fade off into normal eyes as they grow. Does this apply to Raptor's Red ruby eyes too? Will those babies which were hatched with full red eyes later fade into snake eyes as they grow?

 

[RampantReptiles]

This brings up a point I have considered before as well. I was thinking the same thing as Bridgette and Kelli. I have noticed the "pupil" in images before but have you ever seen any variation in the "pupil" size? I have never seen the red either dilated or constricted. It always appears to be roughly the same size...which makes me think it is a reflection of some sort.

I dont think you will see the pupil any other size. Since it requires a lot of light just to see it, the pupil will always be constricted from the massive amount of light the eye is receiving.
Maybe if someone tried doing testing with a black light you might get different results. Do black lights make the eye constrict in leopard geckos?

 

[RampantReptiles]

As i knw black eclipse eye might fade off into normal eyes as they grow. Does this apply to Raptor's Red ruby eyes too? Will those babies which were hatched with full red eyes later fade into snake eyes as they grow?

Some might fade to partial filled eyes. I have never seen a solid eyed baby fade to snake eyes... Red ruby eyes are just eclipses that are albino. The only difference is the darkened part of the eye is red instead of black.

 

[Landen]

I'm not sold on Eclipse being recessive... I've produced several "eclipse" eyed hatchlings over the last couple years from a patternless stripe (no eclipse lineage) paired to an enigma (from a Bold Stripe X Bee pairing), these hatchlings have all come out with odd Triangular shaped "eclipse" eyes. (I've held these back and will be pairing them together to see what they produce)

There just seems to be so many different variations and different ways to produce these "Snake Eyes"... I'm starting to think that something else is causing these. I am glad that you started this thread Kelli and look forward to seeing other opinions about all of this.

 

[SFgeckos]

Great topic and interesting discussions so far!

I produced my first eclipse/snake eyed offspring from patternless stripe parents as well.

I would like to clarify some confusion on several postings using anatomical terminology pertaining to the eye. To be honest, some of the things said don't make any sense. The eye is quite complicated and anatomically, it is a nightmare to learn and understand easily. I'm going off memory so I apologize in advance if I make any mistakes, please make sure to double check anything I say!

The eye contains three tunics, a complete external fibrous tunic that gives the eye shape and protection (sclera/cornea), a middle vascular tunic which consists mainly of blood vessels and smooth muscle pertaining to nutrition and regulation of the lens shape/pupil size (choroid/ciliary body/iris), and the internal tunic comprised of nervous tissue and translation of nerve impulses from visual stimuli to the brain (retina). If one were to start at the front of the eye and proceed through it toward the brain, the anatomical structures/layers we are discussing would be in the following order (please remember I'm trying to keep this simple and name the major ones, there will be minor structures and histological layers I won't include): cornea, anterior chamber, iris attached by spincter and dilator muscles, pupil (which is a space created by the iris and can not contain "color"), lens attached by ciliary bodies, and posterior chamber, etc. The "color" of the eye for humans and many mammals (cats/dogs, others) comes from the iris, however in this particular discussion I believe that the "red color" seen in photographs of eclipse leopard geckos (using a flash) is actually the reflection of the vasculature/blood vessels at the back of the eye showing through the pupil. The choroid layer of the vascular tunic contains network of blood capillaries, usually embedded in pigmented connective tissue. These vessels are responsible for the nutrition of the retina and are also the "red" color seen on the fundus during an eye examination using an opthalmoscope. However, many nocturnal animals (cats, raccons etc but not leopard geckos) have a unique light reflecting area on the fundus known as the "tapetum lucidum". This is what makes their eyes "shine" when light reflects say if you spot them with a flashlight or headlights of your car. The theory is that the tapetum is an adaptation for nocturnal life which stimulates more light sensitive receptor cells to aid vision in darkness. I have spent time examining my own collection of eclipses/snake eyes and my best guess is that they carry some genetic mutation that causes hyper-pigmentation to the iris, either partially or fully at the mesenchyme layer of the optic cup during eye development.

In conclusion, I have no clue what is really going on with eclipses haha! But I really like them =)

Jon

 

[lillith]

Could it just be increased translucency/transparency or the iris? Or conversely, maybe even a hyperpigmentation?
When I looked at my eclipse, I could see a pupil, just like you can in fat-tailed gecko eyes. Is there a known reason fat-tails have completely dark eyes? I'm guessing it was an ancestral trait in prehistoric Eublepharines, especially the most nocturnal ones. It is an adaptation that helps the eye collect more light in low levels (brown eyes in people work like this?). The brighter the eye, the more light it reflects.

Going out on a crazy limb, what if it reflects the ancestral environment? Fat-tails live in a slightly more humid environs, don't they? Could it be that ancestral geckos lived in a more scrubby or treed savannah? With more plants casting shadows?

I know that's really goofy.
That's not what physically is going on, either, just a wild conjecture.

 

[tlbowling]

closest i can think of just by looking is a detatched retina. i am sure it isnt that but it looks similar.

also sometimes dogs have two different colored eyes or one eye with two colors. i have seen that in ausies.

Same with Huskies

Someone else has posted once that this red slit in the pupil is a reflection of your flash, just like people get red eyes on a photo. Don't know if this is true, but it sounds plausible.

Chrissy

Where's Mythbusters when you need 'em?

 

[lillith]

@SF Geckos
Maybe the fibrous tunic is missing/hyperpigmented? I think that might be what I was thinking of when I said "transparent". I saw your post after I made mine.

 

[SFgeckos]

"@SF Geckos
Maybe the fibrous tunic is missing/hyperpigmented? I think that might be what I was thinking of when I said "transparent". I saw your post after I made mine."

That is very unlikely because the fibrous tunic consists of the cornea and sclera. If it was hyperpigmented, the animal wouldn't be able to see through the cornea and if the fibrous tunic was missing the eye would most likely deteriorate.

Jon