snake vision

~Suntiger~ · 12-20-03, 03:46 PM

Does anyone know exactly what snakes perceive through their eyes? Do they see in colour/some colour? Is it different from species to species? Any info would be great! Thanks in advance!

Vanan · 12-20-03, 03:55 PM

That's something I've always wondered and hoped that someone would spend the time and effort researching that.

C.m.pyrrhus · 12-20-03, 04:03 PM

In short, snakes do see in color. Their eyes contain rods and cones as we do, yet do not have the variety of photoreceptors that we carry, so their color perception is not as expansive. Snakes, being eyelidless, have a filter that works to absorb harmful ultraviolet light as well.

Of course there are snakes that can also see by means of infrared detection. Pit-vipers and some boids are included here.

Lisa · 12-20-03, 05:14 PM

I was on the understanding that snakes and cats had similar eye setups and while they could see in colour they had poor vision (blured etc).

reptile171 · 12-20-03, 07:44 PM

ive always heard they just see in heat vision...

Lisa · 12-21-03, 10:30 AM

Quote:

Originally posted by reptile171
ive always heard they just see in heat vision...

Snakes don't see in infrared unless they have pits. for example pit vipers and pythons have pits. i've heard some boas have pits but i have no data backing it up.

JD@reptiles · 12-21-03, 01:01 PM

i want to learn more about the vine snake and twig snake vision. they are supposed to have the best vision of any snake in the world with the horizontal pupils. i know they have a great eye for movement and they are great at judging distances, but i hear snakes only see in a black and white with an orange colour covering everything (if that makes any scence to you).

Take care

Jordan

C.m.pyrrhus · 12-21-03, 01:41 PM

The Corallus group of boa all carry heat pits. The most well known of the species is of course the emerald tree boa. Pretty neat to see the convergence between ETBs and GTPs as well as some of the known vine snakes.

Jeff Hathaway · 12-21-03, 06:19 PM

Technically speaking, the use of infrared sensing pits is not necessarily 'seeing', as in using 'sight'. But it does make a great deal of sense that species which strike out at birds would use either better than average eyesight, or infrared pits, to locate their prey. That ETB/GTP convergent evolution is definitely quite amazing...

As I understand it (and I'm quite willing to be corrected!) snake vision does vary a lot between species, but generally they have fewer cone cells than rod cells, compared to humans. Since cones in humans are the colour sensing cells, it is assumed that snakes do see colour, but not as well as we do.

I'm not aware of any detailed studies of snake vision- perhaps someone with easy access to a university library could have a look (how about it, Ryan?). However, my old animal physiology text does mention that rod cells sense colour in some vertebrates, and specifically mentions frogs.

Jeff Hathaway
Sciensational Sssnakes!!

RachelS. · 12-21-03, 06:33 PM

I do agree with most of the replies here. Correct me if I'm wrong, but to my understanding snakes cannot view red coloration and some other colors as well.

Sean_.E. · 12-21-03, 09:05 PM

I think I have some information about snake vision in one of my books. I know I have a diagram that shows how vine snakes see.

I'll look into it...

C.m.pyrrhus · 12-22-03, 03:54 AM

As I take it, pit-vipers do "see" and image with their pits. I cannot find a lot of anything, due to lack of books and so on. Yet what I have found relates the pit vipers as able to make an image of what they see from their pits. The way their heat seeking abilities are set up, being heavily modified over the boids, is picked up by the sight processing and is "formatted" into an image in the brain. Testing was done with rattlesnakes, their pits blocked and showed that an average of only 1/3 of the strikes made their targets. With their pits unblocked and eye sight blocked, they had an improved strike percentage.

Soul_Reaper · 12-22-03, 11:05 AM

This is very interesting, i was also very curious about how snakes eyesights are. I've always thought they had poor black & white vision kinda thing...i don't why i thought that actually.

Keep the info comming, this is pretty cool.

Knightmare113 · 04-04-04, 08:49 PM

Just thought someone might be interested in the research being done on snake vision. http://abcnews.go.com/sections/scite...ard020109.html

Big_V · 04-04-04, 09:38 PM

There was a program on The Discovery Channel a few months back on this topic. It did a documentary on snakes and really went into how snakes use their senses and how good there vision really is. There may be something on their site that may help you guys out.