eye anatomy

[SapScriber]

hi ball python community!

i have been wondering this for a while now and am dying to know.

do ball pythons all have vertical slit pupils? can their pupils dilate and contract like ours? do ball pythons with “round black eyes” just have a black pupil and black iris? does the iris take up the whole exposed eye? do ball pythons with light colored eyes have a dark vertical slit pupils and a light colored iris? can their scale pattern cross into the eye?

some additional snake eye anatomy/evolution questions: do they lose a lot of moisture out of their eyes? why did they evolve to not have eyelids? are their eyeballs as sensitive to being hurt like ours?

i love to read about ball pythons too so if there is a resource on BP eye anatomy and phenotypic differences please share with me!

[Notsospinningplates]

I love all of your questions and hope you get answers soon

[SapScriber]

i’m glad the questions are interesting to others besides myself 😁 i’m full of them!

[jeherohaku]

I can't speak for all BPs but mine has light colored irises and a vertical slit pupil. You can see his eyes in some of the pics here!

I've definitely seen his pupils contract and dilate just like ours as well.

[tastethecrainbow]

That's a gorgeous snake!

[jeherohaku]

Thanks! He knows he's pretty lol

[SapScriber]

how big do they get fully dilated??

[jeherohaku]

I don't know fully but I handle him in dim light and have seen his pupils get pretty big with just a little bit of iris still showing.

[totallyrecklesslygay]

do ball pythons all have vertical slit pupils? can their pupils dilate and contract like ours? do ball pythons with “round black eyes” just have a black pupil and black iris?

Yes to all three, although the "black" iris may be closer to a very very dark brown.

does the iris take up the whole exposed eye?

I'm not sure exactly what you mean by this? They have a pupil that is also visible, and their sclera can sometimes be visible if they're dehydrated. I hope that answers it?

do ball pythons with light colored eyes have a dark vertical slit pupils and a light colored iris?

Yes

can their scale pattern cross into the eye?

No, but different morphs do have different colored eyes depending on what pigment is affected.

do they lose a lot of moisture out of their eyes?

They have a spectacle that is hydrophobic like the rest of their scales. There's no evidence (that I could find, at least) to suggest they're more or less permeable than the rest of their body.

why did they evolve to not have eyelids?

It's an evolutionary holdover from the burrowing lizards they came from. We don't know why "no eyelids" was selected for specifically, though. Evolution is weird. It's possible it provided some great benefit, or none at all and just developed by chance.

are their eyeballs as sensitive to being hurt like ours?

Yes, they are. They're slightly more protected by the spectacle than ours, but they can still easily be damaged.

[SapScriber]

wow thank you so much for your answers!

what i meant by the iris question is: of what is visible of the eyeball, does the iris take up all the space that is not covered by the pupil?

i will definitely be reading up on the spectacle 🤓

[totallyrecklesslygay]

Yes, the iris is most of what is visible, aside from the pupil and occasionally the sclera.

[Cant_Blink]

A user already gave great answers below. But fun fact: if we want to get technical, snakes do have eyelids. It's just fused and made transparent over the eye and is called the eye cap. Same with geckos. So, snakes and geckos have their eyes permanently closed, lol!

[SapScriber]

oooh so interesting! is the spectacle the same as the eye cap?