# organisms living outside our normal parameters? **URL:** \ **Category:** Factual Questions\ **Created:** [October 11, 2012, 5:42am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395 "2012-10-11T05:42:15Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![crypto](https://avatars.discourse-cdn.com/v4/letter/c/b3f665/32.png) [@crypto](https://boards.straightdope.com/u/crypto)\ **Post date:** [October 11, 2012, 5:42am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/1 "2012-10-11T05:42:15Z")
are there any organisms out there that have been discovered that do not live within the visible spectrum? Is this even possible? I know this sounds like a really stupid question, (and it REALLY sounds stupid when you type it out), but animals can communicate outside the normal range of human hearing. it would seem to me that it could be possible that an animal could be invisible to us because it didn’t reflect light within the visible spectrum. As counter-intuitive as this sounds, does one actually exist? Can it? And if it can’t, why not? If it did, I can’t imagine the size of a creature being large. Please, give me the answer gently. I’d blame the question on my five year old. But I don’t have a five year old. ETA: I’m not referring to something microscopic, invisible to the naked eye. And I doubt the answer is “Yes, they are all around us, you just haven’t bumped into them yet.” Sort of like the ball players in the movie “Field of Dreams”. No, I am NOT drunk, or under the influence of anything that I am aware of. 😉 ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [October 11, 2012, 5:50am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/2 "2012-10-11T05:50:40Z")
> [@Stink Fish Pot](#): > > possible that an animal could be invisible to us because it didn’t reflect light within the visible spectrum. if it didn’t reflect any light in the visible spectrum it would appear to be black as it would be absorbing all the visible light that fell onto it. To be invisible your creature has to be transparent with transparent organs as well, or change colors to mimic the environment. See Jellyfish and Squid. ---
**Author:** ![crypto](https://avatars.discourse-cdn.com/v4/letter/c/b3f665/32.png) [@crypto](https://boards.straightdope.com/u/crypto)\ **Post date:** [October 11, 2012, 6:03am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/3 "2012-10-11T06:03:42Z")
Well, the orgqns were what almost stopped me from even posting this. obviously, everything about the animal would have to follow thw same rules, or youd see the heart, stomach, whatever. And even if they followed those rules, one vitemamd youd see a chunck of food just floating along, inside the animals invisible innards. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 11, 2012, 6:12am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/4 "2012-10-11T06:12:06Z")
This was a reasonably common theme in golden era SF- an entity that was ‘:)a colour we can’t see’ - but as \*\*coremelt \*\* rightly notes, thats just another way to say black. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 11, 2012, 6:12am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/5 "2012-10-11T06:12:07Z")
There are nearly transparent fish. Not totally transparent though. The totally invisible ones would have to remain that way after death until they decomposed sufficiently to be undetectable. ---
**Author:** ![jackdavinci](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackdavinci/32/3259_2.png) [@jackdavinci](https://boards.straightdope.com/u/jackdavinci)\ **Post date:** [October 11, 2012, 6:14am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/6 "2012-10-11T06:14:52Z")
There are a few transparent organisms but like glass, they still refract light, so they aren’t invisible. ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [October 11, 2012, 6:17am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/7 "2012-10-11T06:17:14Z")
To be invisible, something would not only have to be perfectly transparent, its refractive index would have to match that of the medium - air, water, whatever - in which it lived. I don’t think you are going to find any, but jellyfish (and similar things like comb jellies) are about the closest. As **coremelt** said, something that did not _reflect_ light wold be black, and (in daylight anyway) black things are usually relatively conspicuous. ---
**Author:** ![crypto](https://avatars.discourse-cdn.com/v4/letter/c/b3f665/32.png) [@crypto](https://boards.straightdope.com/u/crypto)\ **Post date:** [October 11, 2012, 6:24am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/8 "2012-10-11T06:24:01Z")
> [@njtt](#): > > As **coremelt** said, something that did not _reflect_ light wold be black, and (in daylight anyway) black things are usually relatively conspicuous. what about in an extreme environment, like an underground cave, where light cannot reach? ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [October 11, 2012, 6:27am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/9 "2012-10-11T06:27:54Z")
> [@Stink Fish Pot](#): > > what about in an extreme environment, like an underground cave, where light cannot reach? If there’s no light a creature can be bright florescent green and it’s still going to be “invisible” to any creature that can’t generate light somehow. Most cave adapted creatures seem to be white, since there’s no evolutionary advantage to having any pigmentation any more. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 11, 2012, 6:28am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/10 "2012-10-11T06:28:02Z")
> [@Stink Fish Pot](#): > > what about in an extreme environment, like an underground cave, where light cannot reach? Everything is invisible where there’s no light. ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [October 11, 2012, 6:54am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/11 "2012-10-11T06:54:50Z")
If you don’t limit yourself to organisms but just try to find substances that fullfil your criteria you’ll find the world sorely lacking in solids and liquids that both match your criteria and are sufficient to build a living organism. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 11, 2012, 7:14am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/12 "2012-10-11T07:14:29Z")
I see the (also common in SF) theme of “a being composed of pure energy” marching in the direction of this conversation, so… Aside from the fact that matter can be regarded as energy, the notion of a ‘being composed of pure energy’ isn’t really viable - electromagnetic energy is generally _trying to go somewhere, fast_ - and an organism won’t remain organised if its organs want to disorganise themselves in every which direction at the speed of light. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [October 11, 2012, 10:32am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/13 "2012-10-11T10:32:14Z")
Let’s put it this way: we haven’t seen any yet. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [October 11, 2012, 11:17am UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/14 "2012-10-11T11:17:59Z")
Pink unicorns are generally held to be invisible. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [October 11, 2012, 1:40pm UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/15 "2012-10-11T13:40:47Z")
> [@Stink Fish Pot](#): > > are there any organisms out there that have been discovered that do not live within the visible spectrum? Is this even possible? > > I know this sounds like a really stupid question, (and it REALLY sounds stupid when you type it out), but animals can communicate outside the normal range of human hearing. it would seem to me that it could be possible that an animal could be invisible to us because it didn’t reflect light within the visible spectrum. As counter-intuitive as this sounds, does one actually exist? > > Can it? > > And if it can’t, why not? > > If it did, I can’t imagine the size of a creature being large. > > Please, give me the answer gently. I’d blame the question on my five year old. But I don’t have a five year old. > > ETA: I’m not referring to something microscopic, invisible to the naked eye. And I doubt the answer is “Yes, they are all around us, you just haven’t bumped into them yet.” Sort of like the ball players in the movie “Field of Dreams”. > > No, I am NOT drunk, or under the influence of anything that I am aware of. 😉 This was the premise of the invisibility of the creature in Ambrose Beirce’s 1893 short story _The Damned Thing_. > **[The Damned Thing](https://en.wikipedia.org/wiki/The_Damned_Thing_(Short_Story))** > > "The Damned Thing" is a horror short story written by American Civil War soldier, wit, and writer Ambrose Bierce. It first appeared in Town Topics on December 7, 1893. > "The Damned Thing" is written in four parts, each with a comical subtitle. The story begins in Hugh Morgan's cabin, where local men have gathered around the battered corpse of Hugh Morgan to hold an inquest concerning his death. William Harker, a witness to the death, enters and is sworn in by the coroner to relate the circumsta... > **[The Damned Thing by Ambrose Bierce](https://www.gutenberg.org/ebooks/23172)** > > Free kindle book and epub digitized and proofread by volunteers. [http://www.sff.net/people/DoyleMacdonald/L\_DAMNED.HTM](http://www.sff.net/people/DoyleMacdonald/L_DAMNED.HTM) The problem with the idea is that your hypothetical thing of an infrared color (or whatever) still has to do something with the visible light that hits it. If it doesn’t let it pass through unchanged, then the object will be visible. Getting the light to pass through unchanged is the hard part. Not only must your thing be transparent, it must have the same refractive index as the medium it’s in – that’s why you can see diamonds and glass and other transparent objects. (and it’s impossible for a solid or liquid to have as low a refractive index as gases. So it’s easier to be invisible underwater). Even if you could manage to match the refractive index at one wavelength, if you don’t match it at all visible wavelengths you’ll still be visible (that’s the basis of Christiansen filters). Aside from tyhis, there are only three ways to be truly invisible (as opposed to camouflaged): 1.) Bend the rays around you, or in some way present the same image/wavefront on one side of you that hits you on the other side. 2.) make sure that you and your background have the same high temperature, so that you and your bavckground are blackbodies em,itting light with the same emittance at al wavelengths, and are overwhelming any other light sources. This will result ion your being vaporized for visible light. You have to decide if it’;s worth it. Might be viable if your opposition only has long wave infrared vision. 3.) Turn out all the lights. In the dark everything is invisible. As long as it can’t see your blackbody emission in the infrared. (like pit vipers and Alien Predators. And covering yourself up with mud won’t help(_Predator_). Nor will standing in a refrigerator, as in _Hardware_ . You have vto cover yourself with cold stuff (_Tremors 2_).) ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [October 11, 2012, 1:50pm UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/16 "2012-10-11T13:50:32Z")
I think an organism could be so large that we could not recognize any form to it, a single cell being larger than our universe for instance. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 11, 2012, 2:13pm UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/17 "2012-10-11T14:13:56Z")
> [@badger5149](#): > > I think an organism could be so large that we could not recognize any form to it, a single cell being larger than our universe for instance. There’s a definitional problem in that idea. But the large size thing isn’t totally ridiculous. The Gaia theory treats the whole earth as something like an organism. It’s not that we don’t see the earth, but until modern times we were something like blind men feeling up an elephant. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [October 11, 2012, 2:20pm UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/18 "2012-10-11T14:20:00Z")
> [@Colophon](#): > > Pink unicorns are generally held to be invisible. So how do we know that they’re pink? ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 11, 2012, 2:27pm UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/19 "2012-10-11T14:27:01Z")
> [@Ludovic](#): > > So how do we know that they’re pink? They’re pink unicorns. What other color would they be? ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [October 11, 2012, 2:27pm UTC](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395/20 "2012-10-11T14:27:11Z")
> [@Ludovic](#): > > So how do we know that they’re pink? You have to take that on faith. [Next page](https://boards.straightdope.com/t/organisms-living-outside-our-normal-parameters/637395.md?page=2)