Do Lizards Have 20/20 Vision?

I think it would be interesting to see the world as every other creature does, if only for a fleeting moment! So, what do lizards see?

 

 

Well…. Lizard (including geckos) and turtle retinas contain multicolored oil droplets in their photoreceptors, so   they can perceive color.    The opsin proteins in the cones in the eye are “calibrated” to detect different wavelengths. In many species, this enables them to see into the higher wavelengths beyond the scope of unaided human vision: into the UV range.

Nocturnal reptiles usually have smaller eyes than diurnal ones, but relatively large pupillary and lens aperture and cornea. This improves their light-gathering ability, but at the same time reduces visual acuity.

Lizards can focus on near and far by squeezing or stretching their lenses, using the ciliary muscles and annular pads. Pupils dilate and contract in response to light. Nocturnal geckos like the tokay have a stenopaic pupil: contracts into a vertical slit composed of a linear array of dots. Some nocturnal lizards have slit pupils, others are round. Lizards, unlike other reptiles, have a choroid body, called the conus papillaris. Projecting out into the vitrious humor, it nourishes the cornea.

*Thank you    http://www.anapsid.org/sight.html

The spectrum of sunlight includes infrared, “visible light” (the colors we see in the rainbow) and ultraviolet light, which is subdivided into UVA, UVB and UVC.

UVA, is essential. Many reptiles have extremely good color vision. Humans have three types of retinal cone cells for color vision, and their brains combine the information from these cells and perceive the blend as a certain color. Most reptiles, however, have a fourth cone type, which responds to UVA. These reptiles see a much more colorful rainbow than humans do, which makes providing natural lighting quite a challenge. This extra color perception is especially important to many reptile species in recognizing others of their species and even food items.

Some nocturnal geckos lack the red-sensitive cone, but their green-sensitive cone also responds to red light; they can certainly see it. Studies have even shown that some use their cone types for color vision in light similar to dim moonlight. Thus it is possible that “moonlight blue” or “red night light” lamps, which usually are much brighter than moonlight, alter these animals’ view of the twilight world.

Sunlight also has effects unrelated to conscious vision. A reptile’s eyes, and the parietal eye (third eye) in those species that have one, transmit information to other parts of its brain responsible for setting circadian (daily) and circannual (yearly) rhythms. There are even light-sensitive areas of the reptilian brain that respond directly to sunlight’s glow through the skull. The length of day and night, the sun’s position in the sky, and the intensity and amount of blue in sunlight all give precise information about the time of day and season of the year. In response, a reptile adjusts its activity levels, and daily and seasonal behaviors, such as its reproductive cycle and thermoregulation needs. Even nocturnal species govern their behavior by monitoring day and night from their daytime hiding places.

*Thank you   http://www.reptilesmagazine.com/Reptile-Health/Habitats-Care/Reptile-Lighting-Information/

…So what have we learned if the study and testing conclusions are accurate?

1. Lizards do see colors.
2. Most reptiles actually see a much more colorful rainbow than we!
3. Most lizards have a parietal eye, known as the third eye, which is a photosensory organ.
4. Also, their pupils dilate and contract, same as ours, to focus on things near or further away.
5. I will further add to this by stating a lizard (specifically Bearded Dragons) close their eyes for 4 reasons:     a) You are overstimulating at the moment OR they don’t like you AND they want you to go away.    b) They are sleepy.    c) They are at this very moment, in perfect peace with their environment & existence.      d) They are feeling love from or toward you right now.

 

* Within our post: Which Lights Do Lizards Need, we highlight the special lightbulbs and their fixtures for your reptilian (and amphibian) family members. We not only share a selection available for purchasing, but we also tell you exactly why they’re needed. Plus, there are helpful and life-saving tips to be read.

*See our chosen selection of vivariums and tanks with beautiful stands here: Best Vivariums and Tanks for Lizards and Snakes.

“Give me Lizardry or give me Death!” – ♥Dawn