Reptile & Amphibian Forums

I was looking into buying the PE-2 temp gun from pro exotics. I allready own the PE-1. When I was reading the information on this gun, I found out that the gun can sense infrared light. What is infrared light in terms of reptiles? Whats the point of detecting it? Can too much effect the reptiles? I know what it is in terms of earth science, but I would rather have an explanation of it dealing with reptiles.

Thank you for all of your help!

-Paul

I'll ramble a little and hopefully something in here is useful.
I think of infrared as being "radiant heat". I believe the technical definition is that it's electromagnetic radiation in the range of about 1 to 1000 micrometers wavelength. We see visible light (refelected off objects) with our eyes in other wavelength ranges but we can't see infrared, we can feel it on our skin and it's penetration is important for reptile health. It is necessary for normal metabolism and digestion. A diurnal (daytime basking) lizard like a uromastyx expects infrared to coincide with bright visible light because sunlight contains lots of visible light as well as invisible infrared and ultraviolet lights all together. They receive all those types of light from above but also infrared from underneath if they lay on a hot rock. I mention this because I believe manmade bulbs/emitters of only a specific radiation-type could possibly fool a lizard's instincts, for example an unnaturally warm but dark surface (the infamous hotrock burns are from too much infrared radiation from below - cooks the tissues just like in an oven if something goes wrong and the reptile doesn't get away). And will a lizard bask if a good UV source doesn't have bright visible light??
A nocturnal reptile will seek out warm surfaces to absorb infrared from below (unfortunately resulting in blacktop roads being a killing field for reptiles seeking heat).
But back to the tempguns. All objects emit IR, the quantity of which is proportional to the object's temperature. So the tempguns measure surface temperatures by detecting the IR radiated from the object. A traditional thermometer must itself be warmed or cooled by it's surroundings to indicate temperature.
Now, for those of you that haven't fallen asleep, I think the tempguns are an incredible bargain and every uro-owner should have one. I am even an authorized distributor and would be happy to sell you a PE-2 but I don't see a huge advantage of the PE-2 for everyone. It has a narrower field of view so you can hold it farther away from the surface being measured which is great for an animal that is timid and easily spooked, or if you've got an agressive jumping croc monitor or keep something like rattlesnakes. (The meanest uro tail sounds pretty mild now, doesn't it?) It has a laser sightbeam which shows you where it is being pointed (but don't be fooled into thinking you are measuring the temp at just that dot - it measures an area and that area is larger the farther away you hold the gun). Personally I use the PE-1 and hold it up close to the surface. Maybe Robyn from Pro-Exotics has some additional comments on advantages I haven't though of.
For more fun, figure out the workings of the pineal eye.

Okay, that was my entire typing quota for November.
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Lindsay Pike
Urotopia Uromastyx

Lindsay,

That was very helpful, Thank you!

Lindsay, isn't it fair to assume that the pineal eye DOESN'T work? Either way, good response!

Dan, I dont think the pineal eye can be ruled out as not working, from what I understand, it is a photoreceptor that acts as a kind of "dawn and dusk detector." I have also read that its importance in circadian rhythmicity varys among the taxa.
-Nat

So it's a developing organ, not a degenerative one like a human appendix? Nat, your & Lindsay's brains are too big for even modern science!! Just don't get me started on the latest findings of the metabolic effects on the biliary system of the female Amphiuma means under induced anoxia...
'Cause I wouldn't even know what the findings mean!
D.

I would have to say its a functional organ. The parietal eye is an archaic structure in the sense that it was much more widespread among earlier reptiles. Now it is most noted in the iguanids, varanids, and the tuatara; as I said in the last post, its importance varies among taxa and is thought to function as a control for thermo-regulation and seasonal reproduction. This is a great thread and maybe someone who is a little more read on the subject can spread more light?

-Nat