# Do we know if there are any senses that we lack the organs to experience? **URL:** \ **Category:** Factual Questions\ **Created:** [July 19, 2006, 9:14pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238 "2006-07-19T21:14:10Z")\ **Posts on this page:** 11\ **Page:** 3
**Author:** ![II\_Gyan\_II](https://avatars.discourse-cdn.com/v4/letter/i/bbe5ce/32.png) [@II\_Gyan\_II](https://boards.straightdope.com/u/II_Gyan_II)\ **Post date:** [July 21, 2006, 3:21am UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/41 "2006-07-21T03:21:46Z")
Re: bird vision, I came across this article in the July issue of Scientific American: [What Birds See](http://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=000DA6AC-F10C-1492-A7CE83414B7F0000): > [@](#): > > Our knowledge of color vision is, quite naturally, based primarily on what humans see: researchers can easily perform experiments on cooperative human subjects to discover, say, what mixtures of colors look the same or different. Although scientists have obtained supporting information from a variety of other species by recording the firing of neurons, we remained unaware until the early 1970s that many vertebrates, mostly animals other than mammals, see colors in a part of the spectrum that is invisible to humans: the near ultraviolet > . . . > our experiments provided evidence that birds use all four cones in their color vision. But it is difficult—impossible, in fact—for humans to know what their perception of colors is actually like. They not only see in the near ultraviolet, but they also can see colors that we cannot even envision. For those interested, I’ve put up the full PDF [here](http://www.yousendit.com/transfer.php?action=download&ufid=4B79031A72400E6B). ---
**Author:** ![Lama\_Pacos](https://avatars.discourse-cdn.com/v4/letter/l/d6d6ee/32.png) [@Lama\_Pacos](https://boards.straightdope.com/u/Lama_Pacos)\ **Post date:** [July 21, 2006, 7:39am UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/42 "2006-07-21T07:39:15Z")
> [@CalMeacham](#): > > 3.) More Degrees of Freedom in Color Vision. Even in the range of visible light, we’re not completely discriminating. In our sense of hearing we can clearly distinguish between different pitches. Even people without perfect pitch can tell the difference between two notes. But we can perceive an infinite number of different spectral combinations as the same “green”, because we only have three degrees of freedom in our color sense. We could conceivably have color sense more like a spectrometer, and be able to distinguish between different spectral compositions that now look the same to us. This seems to me more a linguistic issue than a sensory one. Sure, we _call_ them all ‘green’, but I think I could probably at least acknowledge the difference between many shades of it. Also, your analogy to music does not seem particularly apt. As far as I’m aware, the division of the spectrum of sound frequencies in Western tradition is equally as arbitrary as a given language/culture’s division of the color spectrum. I might be wrong on this one though. ---
**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:** [July 21, 2006, 11:40am UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/43 "2006-07-21T11:40:22Z")
> [@](#): > > This seems to me more a linguistic issue than a sensory one. Sure, we call them all ‘green’, but I think I could probably at least acknowledge the difference between many shades of it. > > Also, your analogy to music does not seem particularly apt. As far as I’m aware, the division of the spectrum of sound frequencies in Western tradition is equally as arbitrary as a given language/culture’s division of the color spectrum. I might be wrong on this one though. No, it’s not linguistic. We can build color TVs using three phosphors, and can do color printing with three colors because we only have three degrees of freedom in our sense of color. If we had four or more, we’d never be able to get away with that – the colors as we print or broadcast them now would look wrong ion some way. Also, with sound, I’m not talking about division into particular notes – the modern chromatic scale or the ancient harmonic scales or the Easternm pentatonic scale. I’m saying that we have much better resolution in sounds than in colors (and I never said it was infinite – any physical receiver is going to have some limiting resolution, determined by its construction). we have more degrees of freedom in our sense of sound than in color. Although we can mix different proportions of spectral compositions together to get the same color as far as our eyes can tell, we can’t construct sounds that seem to be the same by playing different chords. And this is as true f you’re a modern American, an ancient Greek, or a Medieval Chinese. ---
**Author:** ![Shalmanese](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shalmanese](https://boards.straightdope.com/u/Shalmanese)\ **Post date:** [July 21, 2006, 11:54am UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/44 "2006-07-21T11:54:39Z")
[QUOTE=Lama Pacos] This seems to me more a linguistic issue than a sensory one. Sure, we _call_ them all ‘green’, but I think I could probably at least acknowledge the difference between many shades of it. [/QUOTE] No, it’s not about different colours being called the same name, it’s about the same perceptual colour having different spectrums. For example, imagine you were able to set up a computer monitor to perfectly replicate a scene as in a [trasparent laptop screen](http://www.flickr.com/photos/w00kie/7234920/in/set-180637/) setup. Pointing a spectrograph at a point on the laptop would yield 3 sharp peaks at red, green and blue and a low level everywhere else due to ambient light. Pointing the spectrograph to the point behind the laptop screen which is the exact same colour and you would get a smooth curve with no peaks. Yet both of these appear the same to the human eye. Another sense that humans are missing is I guess what would be called “3dness”. We can simulate a crude 3d perception of the word through parralax vision but it’s not true 3d. A true 3d sense would be able to distinguish a hollow sphere from a solid one. However, for such a sense to exist, the sensorary organ would probably have to reside in the 4th dimension which doesn’t seem all that practical or even possible. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [July 21, 2006, 2:38pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/45 "2006-07-21T14:38:45Z")
[QUOTE=Lama Pacos] This seems to me more a linguistic issue than a sensory one. Sure, we _call_ them all ‘green’, but I think I could probably at least acknowledge the difference between many shades of it. [/QUOTE] As has been already pointed out, the issue is not linguistic. The different “colors” that can be perceived depends on the number and sensitivity of different color receptors an animal has. To give a simplistic and somewhat artificial example, we perceive the combination blue + yellow as green. A dog, with only two kinds of cone cells, may not be able to distinguish green from other colors that we can tell apart with our three kinds of cone cells. One the other hand, a bird, with four kinds of cone cells, will perceive UV + blue to be a color as distinct from blue as blue and green are to us, and one that we can no more understand than a dog can know what “green” is. As the Scientific American article linked to above mentions, birds and other animals also have oil droplets in the eye that help to fine-tune the response of each type of cone cell, giving them an even greater ability to distinguish shades of color. ---
**Author:** ![bouv](https://avatars.discourse-cdn.com/v4/letter/b/bc8723/32.png) [@bouv](https://boards.straightdope.com/u/bouv)\ **Post date:** [July 21, 2006, 3:18pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/46 "2006-07-21T15:18:52Z")
Well, we certainly don’t have smission. 😃 ---
**Author:** ![First\_Amongst\_Daves](https://avatars.discourse-cdn.com/v4/letter/f/4491bb/32.png) [@First\_Amongst\_Daves](https://boards.straightdope.com/u/First_Amongst_Daves)\ **Post date:** [July 21, 2006, 3:40pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/47 "2006-07-21T15:40:00Z")
[QUOTE=CalMeacham] 4.) Improved depth perception [/QUOTE] Extra eyes? I’m guessing animals like spiders have very very good depth perception. ---
**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:** [July 21, 2006, 3:52pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/48 "2006-07-21T15:52:28Z")
> [@](#): > > Extra eyes? I’m guessing animals like spiders have very very good depth perception. That’s precisely what I was thinking. You could improve the parallax if you had more separations available, or more planes of parallax (we’re restricted to one plane, with two eyes). Like Spiders. Or Dr. Jumba Jookiba: [http://fan.star-wisher.com/jumba/](http://fan.star-wisher.com/jumba/) ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [July 21, 2006, 4:53pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/49 "2006-07-21T16:53:48Z")
> [@](#): > > So we could imagine a spectroscopic eye that worked the same way. You’d need a prism lens that split the spectrum, then the spectrum would fall on an array of optical sensor nerves. You wouldn’t need them to be as finely sensitive as our cone cells, but due to the prism they’d only activate if light of a known wavelength stimulated them. Pack in enough cells and you’d have a spectroscopic eye, fine enough and you’d be able to see emission and absorbtion lines. Of course, this eye would be useless for seeing images. And Nyarlathotep knows what an organism could actually USE this eye for. There’s a lot of work done in spectroscopic imaging instruments, of various designs. It’s easy enough to get one axis of spatial information and one of spectral information, of course. Then, you can use multiple slits, or scan your slit across an image, to get the other dimension. Alternately, you can use a standard imaging system, but with a large number of filters: This would be analogous to increasing the number of types of cones in our eyes. Or you can combine spatial and spectral information in various ways (interestingly, the deconvolution for some of these methods is very similar to the analysis the brain has to do to convert two 2-d images into a single 3-d image). Or you could attempt to construct a detector which inherently measures the spectrum: For instance, you might have a thick receptor, into which different frequencies penetrate different distances, and the 3-d information of where a photon were detected would then give you full spectral imaging. As for use, it would enable the organism to precisely distinguish between different chemicals by sight, which might be useful for identifying foods with various toxins or essential nutrients. ---
**Author:** ![MagicXylophone](https://avatars.discourse-cdn.com/v4/letter/m/b19c9b/32.png) [@MagicXylophone](https://boards.straightdope.com/u/MagicXylophone)\ **Post date:** [July 21, 2006, 5:37pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/50 "2006-07-21T17:37:40Z")
I remember a science fiction short story I read once about people from another dimension - they were humans, just living in a sort of alternate reality - who had developed all of their geometry based on non-Euclidean concepts. A scientist in this alternate-reality was attempting to time travel, and as a test he sent some of his child’s simple toys in a box into the void. The toys came to our universe, where a boy discovered them and tried to play with them, only to realize that they were totally illogical because his Euclidean-conditioned mind couldn’t figure them out. IIRC, one of the toys was an anatomically correct doll that had all the features of normal humans, plus some sort of “new” system that pervaded throughout the body. A very very hard to follow summary, but it was called something along the lines of _“Mimsy Were the Borogroves”_ or something. [/hijack] ---
**Author:** ![indecisive1](https://avatars.discourse-cdn.com/v4/letter/i/41988e/32.png) [@indecisive1](https://boards.straightdope.com/u/indecisive1)\ **Post date:** [July 22, 2006, 12:43pm UTC](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238/51 "2006-07-22T12:43:23Z")
[QUOTE=Lemur866] But what exactly is “fear”? A sense is a nerve receptor that discharges when it gets a certain physical stimulus. What physical stimulus does “fear” cause? We “sense fear” by our regular senses…we see someone’s face and movements, we hear their voice, we smell their sweat, we use our brains to infer the person’s internal emotional state by their outward physical state. And we can do this with other animals too, especially if we have learned to read their body language. Pretty much anyone can tell when a dog is scared or when a cat is scared, many people can tell when a horse is scared, we could probably do a pretty good job telling if a monkey is scared. But sometimes we misinterpret those signals, how do you distinguish between fear and aggression, since an aggressive animal is likely to be fearful as well? The fact is, there is no “fear particle” that can be detected by a nerve cell. Just because a trait would be advantageous to have does not mean an organism will have the trait. So the ability to sense emotions is impossible because emotions are all in your head, they aren’t broadcast into the universe by any mechanism. The only way we can detect emotions is to infer them by observation of the organism experiencing (or not experiencing) the emotion. [/QUOTE] But if we can hear their voice and smell their sweat, are they not broadcasting particles? Could it be that fear causes our bodies to emit particles that we have no means to detect? [Previous page](https://boards.straightdope.com/t/do-we-know-if-there-are-any-senses-that-we-lack-the-organs-to-experience/365238.md?page=2)