Talk:Tetrachromacy

message: Why is there a student essay referring to a study on female human tetrachromates as an external link instead of the study itself - or at least a more normal article reporting on the study like http://scienceblogs.com/cognitivedaily/2005/09/do_women_perceive_color_differ.php --Troed 21:45, 23 January 2007 (UTC)
thread_title: Comments

message: The article states that over 50% of women and 8% of men may be tetrachromats.
The linked reference has no mention of male tetrachromats, and other references make it clear that tetrachromats can only occur in females (or at least people with two X chromosomes) I think the statement is a misquote?
59.167.121.128 (talk) 14:51, 28 August 2008 (UTC)
thread_title:  Tetrachromats can only be female! 

message: In Calomhe's article, "Up to 50 per cent of women are tetrachromatic and can use their extra pigments in 'contextually rich viewing circumstances'.", she must've meant "Up to 50 per cent of women who are tetrachromatic can use their extra pigments in 'contextually-rich viewing circumstances'."
We desperately need a test for tetrachromacy, and for tetrachromats to point out where extra divisions of hues are, say, on the RGB wheel.  Do tetrachromats see a breakup of symmetry on the wheel?  Also, whenever I see red I get an odd feeling that the red is always tinged with orange.  Is this true of most people, or is this a tetrachromatic effect, or am I just slightly red-blind?  I do though, in principle, understand and see the difference between red and orangey-red. lysdexia 03:03, 23 Nov 2004 (UTC)
replies: text: A few weeks ago I read an article in an ophthalmology journal about this, only I forgot to take notes. They tested twenty thousand women with the gene for tetrachromacy and found that it was only expressed in one person. She had a fourth cone somewhere within the normal range of vision, in between two of the other cones (in terms of peak sensitivity). They subjected her to a battery of vision and color perception tests. As far as they could tell, the fourth cone had absolutely no effect. Zyxwv99 (talk) 02:33, 3 September 2013 (UTC)
thread_title: uhm

message: I am concerned about they way this article suggests that there are human tetrachromats walking among us.  In theory it may be possible, in practice I am not aware of any fully confirmed cases.Ken McE (talk) 23:36, 21 December 2007 (UTC)
replies: text: I find the current formulation ("It has been suggested that women who are carriers for variant cone pigments may be born as full tetrachromats") overly cautious. I am not advocating that the we present the theory of female human tetrachromats as a fact, but this formulation almost ridicules the possibility that the theory may be true. — Adhemar 20:35, 14 September 2006 (UTC)
thread_title:  Human Tetrachromats?? 

message: http://vm.uconn.edu/~lundquis/links.html
suggests diet can extend IR senstivity
but
http://www.google.co.uk/search?q=carrots+night+vision
suggests this may be propaganda.
Doubt if it's a 4th channel, though !
--195.137.93.171 00:41, 8 September 2007 (UTC)
thread_title:  Wartime Experiments 

message: I've heard of Individuals being able to see additional colors in connection with LSD use (apart from being able to see sound). This would disprove that a trichromat can not "imagine" a tetrachromatic colorspace. However there does not seem to be much research on LSD in connection with tetrachromacy. 83.64.17.44 11:16, 6 March 2007 (UTC)
thread_title:  LSD use 

message: I want tetrachromacy ! damm ! what do we guys get they don't , I want to lord it over them for once!
somebody help me find something (other than what hanges twixt my legs ;-) that I have that they don't.
Hi, in exchange for lesser color vision men get better night vision.  So go out tonight and enjoy it!  Ken McE 21:42, 14 August 2007 (UTC)
thread_title:  whaterver 

message: The article says Tetrachromacy has not yet been discovered in any mammals and later says at least one tetrachromat has been identified - "Mrs. M" ...  Is she not a mammal? Don Don 18:44, 31 March 2007 (UTC)
replies: text: No: humans are glorious spiritual beings set apart from all the base creatures of the... uh, fine you're right, she's a mammal.  Not sure how we should change the article to reflect this.  I guess: "only one confirmed case of tetrachromatism has been discovered in mammals"  ???  Sound good?
No, it does not.  It has not been solidly confirmed that she is a tetrachromat.  Ken McE 21:44, 14 August 2007 (UTC)
thread_title:  Contradiction? 

message: Just wondering why no one has created a test similar to the Ishihara color test. It seems that the approximate maximum sensitivity of the fourth cone could be experimentally determined from perceptual studies on potential tetrachromats. These tests could be performed similarly to the experiments performed by Wright & Guild to formulate the CIE 1931 color space. Then, based on that wavelength, images could be created analogous to the Ishihara test images, in that some would contain symbols that only tetrachromats could distinguish. I know i am oversimplifying the issue, but it seems pretty straightforward. Straha 206th 22:44, 28 June 2007 (UTC)
replies: text: I believe some tests were done in this  experiment which suggested the lizards were tetrachromats (i.e. actual perception tests, not just the pigments are there tests). It may have also mentioned some other perception experiments Nil Einne 12:31, 9 October 2007 (UTC)

text: The Ishihara test may be useful.  From my own experience, I see colors quite well, but I can't see most of the numbers on the Ishihara test.  I just see a multitude of colors.  This may relate to the fact that my father and son are color blind, so I carry some sort of anomaly.  — Preceding unsigned comment added by Mamjean (talk • contribs) 03:23, 9 August 2012 (UTC)

text: I'd like to make a note that a google search for this is probably futile, as monitors were no doubt designed for trichromats.  74.64.80.193 (talk) 04:49, 12 January 2013 (UTC)
thread_title:  Tetrachromat Testing 

message: I don't really know much about bird gender and genetics, but I was wondering if the possibility of  tetrachromacy is reserved for human women, is it the same in other animals and insects. In the case of birds, it would add another dimension to the high sexual dimorphism, specifically, male plummage. Now that their finding even more difference that were previously undetectable in the human spectrum of sight in birds feathers, are these difference just for the females?71.235.115.115 03:33, 19 July 2007 (UTC)
replies: text: (Crossposted reply) - Birds are tetrachromatic having cones for the red, green, blue and UV regions of the spectrum. As far as I am aware there is no widespread sexual difference in colour perception in birds. The signals you dexcribe that they can percieve but we can't are UV in nature but are used for signalling to both species. I'll amend the article to include mention of tetrachromacy. An interesting subject we allude to without directly mentioning. Sabine's Sunbird  talk 04:25, 19 July 2007 (UTC)
thread_title: Birds

message: The last paragraph in this section suggests that the extra information from an additional cone would get muddled in the brain, but recent studies (see link for article) with genetically modified trichromatic mice show that they are able to select a colored panel for a treat 80% of the time compared to 1/3 of the time for the control mice.  I believe this shows a flexibility of the mammalian mind that could allow a tetrachromatic human to fully utilize the extra information.
Further more, I recently watched the movie "in pot we trust" which features a San Diego police officer with an extraordinary ability to distinguish between shades of green, allowing him to spot marijuana plants from a helicopter.  I believe it is possible that he is a fully functioning tetrachromatic.
http://www.physorg.com/news93792566.html  �Preceding unsigned comment added by 71.160.237.237 (talk) 17:15, August 29, 2007 (UTC) 
Hi 71.160,
I meant to suggest that it is difficult, not that it is impossible.  We know that it is biologically possible, we just don't know if *we* could handle it.Ken McE (talk) 23:51, 21 December 2007 (UTC)
replies: text: I find the problem with the "Difficulties" section to be as follows: it posits the arrival of tetrachromacy as an ADDITION to an already existing brain / nervous system (with words such as "it is not clear if the nerves could handle the extra channel").  For a person born with this condition, there would be nothing extra -- the brain and nervous system would have been presented from the very first moment with 4 different signals.  Since it is not clearly understood how the brain makes sense of the three signals it receives in normal trichromatic vision, it seems somewhat limiting to assume that the brain of a tetrachromat could not make sense of the extra sensory input. WikiDan61ChatMe!ReadMe!! 18:43, 22 April 2009 (UTC)
thread_title:  Possibility of human tetrachromats 

message: The question I find fascinating, that I have seen no research on, is this: since RGB monitors present information approximately mapped to a human's three color receptors, how does a tetrachromat's perception of RGB colors vary from a trichromat's.  For example, if a screen is displaying a yellow image, there are red and green pixels lit.  There is no actual yellow light, but the trichromat's receptors are stimulated in the same proportion as they would be if pure yellow light were presented, and the person perceives yellow.  However, the screen ONLY stimulates the tetrachromat's red and green receptors, and not the intermediate (orange?) receptor in the same way that the pure yellow light might, so does the tetrachromat perceive the image as something other than yellow?  If so, this must make the world of computer imagery (and televison and three-color printing, etc) truly maddening to such people. WikiDan61ChatMe!ReadMe!! 18:43, 22 April 2009 (UTC)
replies: text: Use a monochrome display and you will understand. Czech is Cyrillized (talk) 06:49, 14 September 2013 (UTC)
thread_title:  Tetrachromats and RGB monitors 

message: For trichromats, there are 2^3=8 basic colours: black, red, green, blue, cyan, magenta, yellow and white. But for tetrachromats, there are 16 basic colours. Let's name the extra colour octarine. The extra basic colours for them are: octarine, octarinish red, octarinish green, octarinish blue, octarinish cyan, octarinish magenta, octarinish yellow and octarinish white.
second that  — Preceding unsigned comment added by 157.193.9.140 (talk) 11:56, 28 July 2011 (UTC)
replies: text: You can't count that way. The cones register colour but rods register light or the lack there off. Therefor black and white (more correctly darkness and lightness) should not be counted as basic colours. When a trichromatic eye sends a signal to the brain, it uses 3 scales, light-dark, red-green, blue-yellow, the human brain then makes an 3D colourspace based on those 3 axis. The bw rgb cmy is a misinterpretation of what colour is. Colour is a wavelength or a combination there of. Normally humans can register 300 different wavelengts, each of which is a basic colour. The number of combinations possible is larger than the human eye can see, and many combinations even thou they are very different will be percieved as the being alike by humans. Red green blue are primary colours in a coloursystems where colours are made by adding light. Cyan magenta yellow are primary colours in coloursystems whre ligth is being taken away. balck and white are not colours. Colour systems made up by 3 components are never able to make all the colours a human can percieve.
A light source sends out up to 300 differnt wavelengts, that are reflected into a human eye. The eye registers lightness, red, Green and blue, and send a signal to the brain in form of a 3D coordinat on the axis red-green, yellow-blue, dark-light, the brain a colourspace and interprets colour by a way simular to longitude, latiude and distance to the core, the brain then associate the colour to a memory or feeling.
The interesting part is not only which wavelenghts a fourth cone may register, but also how they are signaled and percieved by the brain.94.145.236.194 (talk) 16:51, 25 September 2011 (UTC)
thread_title:  Basic colours 

message: I assume that the left and the right eye do not have rods and cones with the same response to wavelength. (Sensitivity is certainly not always the same.) In that case, it's possible, isn't it, that humans can see six primary colors, or including the greyscale possibilities discussed above, eight?
Piano non troppo (talk) 07:09, 16 September 2008 (UTC)
thread_title: Left and right eye variations

message: Is there a discrepancy betweeen the several statements in the article which treat the human tetrachomatacy as an unconfirmed hypothesis:
:Further studies will need to be conducted to verify tetrachromacy in humans. Two possible tetrachromats have been identified [...]
:It is possible that some humans could have four rather than three color receptors.
and the one near the end which seems (to a lay reader, at least) to treat it as an established phenomenon:
:People with four photopigments were shown to have increased chromatic discrimination in comparison to trichromats.
...or am I missing something here? Dependent Variable (talk) 21:13, 26 September 2008 (UTC)
thread_title: Discrepency?

message: It's very unlikely women with two gene sets encoding for photoreceptor pigments with a different wavelength responsiveness for each set can ever take advantage of such trait. The explanation grounds in two facts. Women are not heterozygotic for most of the X chromosome genome at the cellular level. Instead, they are mosaic, i.e., only the genes present in the major part (including the genes encoding for the pigments) of one of the two X chromosomes will be expressed in every single cells. This is not enough to explain my assertion as in any cone cell only one of the different pigments are already expressed, and even so, the color sensitive mechanism is able to integrate the information coming from different color-specific cone cells to resolve the wave length that excited to those cone cells. The main problem is the way in which most of the genes present in one of the two X chromosomes are inactivated in every cell. In most mammals during the development of the embryo one of the X chromosomes is inactivated at random in every cell (under normal conditions). All the descendants of the these cells will inherit the same inactivated X chromosome. Usually this inactivation is permanent. That gives rise to a distribution pattern in most solid tissues in which cell patches share the same inactivated X chromosome, all those cells derived from the same embryonic cell. The whole tissue is a succession of patches in many cases of macroscopic size. Thus, there's no use of having two different pigment sets if all the neighbor cone cells around just express one pigment of always the same the pigment set, that is, the pigment set encoded in the X chromosome that escaped the chromosomic gene inactivation. Only in boundary regions between patches could be integrated the information provided cone cells expressing pigments of the two sets. The only way to achieve a functional color discrimination would be that the retina cells coming from different early progenitor cells being well mixed to reach a similar cone cell proportion for each different pigment in every tiny photosensory area of the retina.
Birds are unlikely to have sexual dimorphism for the color perception because sex chromosomes have evolved separately in mammals and birds, thereby, most genes present in the X chromosomes are not found as homologue genes in the bird sex chromosomes. But what makes almost impossible to occur is to find a male bias for a sex-linked recessive disorder since in birds the heterozygotic for the chromosomic sex determination is the female. Bird females are WZ whereas males are ZZ. If there's a gene mutated in the Z chromosome and the mutation is recessive it is more likely that the affected individuals be females since they just have one Z chromosome and therefore, only one copy of the gene (if there's just one copy of this particular gene in the haploid genome). Interestingly, in birds two sets of genes in the Z chromosome coding for different pigment sets could increase the effective color discrimination in males since in birds there isn't Z chromosome inactivation. Instead the genes of both Z chromosomes are downregulated to compensate the gene expression dose with the female gene expression (alternatively it can be said that the genes present in the female single Z chromosome are upregulated to reach the same dose as in males).
Heathmoor (talk) 01:16, 30 October 2008 (UTC)
thread_title: No functional female tetrachromats found among humans. Unlikely sexual dimorphism among birds but never male-biased defective color perception

message: Stop reverting my edits unless you got a sufficient knowledge on such things as spectral colors and chromaticity. For 3chromatic vision we can match any given chroma by a mixture of two chosen waves, and can make it in infinitely many ways (1-parametric family, because one degree of freedom is spare). But you can not find such three fixed waves which can match all chromas (even in trichromatic vision), you can not obtain a full gamut even by any finite number of fixed waves. Incnis Mrsi (talk) 09:45, 27 January 2009 (UTC)
replies: text: As it happens, I am an expert on colorimetry and color vision and photography.  I re-editted this bit to make the intended meaning more clear.  It's true that you can make an arbitrary color from two specially chosen monochromatic colors, but I think that's not the kind of point that was intended there. Dicklyon (talk) 18:01, 27 January 2009 (UTC)
replies: text:  Yes, I also thank that it's 3-dimentional chroma (instead of 2) the essential property of tetrachromatic vision, but not imaginable experiments with matching colors using monochromatic lights. That's why I removed the statement, but you considered it as my mistake. Incnis Mrsi (talk) 19:24, 27 January 2009 (UTC)

text: I don't know anything about her.  Oh, I see, you're referring to my revert of an uncommented change of physician to interior decorator.  If that was you, and it was serious, be aware that an edit summary will go a long way to distinguishing such an edit from drive-by vandalism.  Dicklyon (talk) 18:01, 27 January 2009 (UTC)
replies: text:  No, I never visited England and do not use proxies in casual Wikipedia edits ☺ Incnis Mrsi (talk) 19:24, 27 January 2009 (UTC)
thread_title:  [[user:Dicklyon|Dicklyon]] 

message: I tried to make it flow a little better; this did unfortunately involve moving some of the text around. I tried to keep the meaning intact, but as someone who has no expertise in the field it would appear from Piano non troppo's revert that I got it hopelessly wrong. Would someone who does know about the subject mind looking at it? - Jarry1250 (t, c) 10:06, 18 February 2009 (UTC)
thread_title:  Difficulties section 

message: The article states that "Rods may help with color vision in low light situations" but doesn't cite its source. Rods, and their photopigment rhodopsin, can't distinguish color. It's a binary pigment. Either light is or is not when it comes to rods. I'm going to remove the line. If anyone can prove me wrong, cite your source first before adding in the information 147.124.150.164 (talk) 15:01, 30 April 2009 (UTC)
replies: text: I added a source; feel free to investigate further and expand or whatever.  Rods are not "binary"; like cones they have their spectral sensitivity curve, which can help distinguish things of different colors, perhaps, when both rods and cones are active. Dicklyon (talk) 22:20, 30 April 2009 (UTC)
thread_title:  Rods and Rhodopsin 

message: This nature paper and the associated news coverage seems to demonstrate that color blind monkeys were able to gain trichromacy by inserting a gene. Since the brains adapted and were soon able to process the new signal, it provides some evidence that the section on 'Difficulties' may not be as difficult as initially supposed. Cariaso (talk) 19:27, 20 September 2009 (UTC)
thread_title: Animal Model

message: http://www.dailymail.co.uk/health/article-2161402/Gabriele-Jordan-British-scientist-claims-woman-superhuman-vision.html  — Preceding unsigned comment added by 76.172.122.94 (talk) 08:59, 19 June 2012 (UTC)
thread_title:  news 

message: Could:
Floral colors were categorized into two main wavelengths of light including 360–520 nm and 400–500 nm. be changed to:
Floral colors are categorised into two main wavelengths ranges of light: 360–520 nm and 400–500 nm.
Thanks for helping me understand. Edouard Albert (talk) 19:02, 15 November 2012 (UTC)
replies: text: I don't know about that specific research, but saying "ranges" is certainly more correct grammatically. I think this is non-controversial enough that you could just go ahead and do it. My opinion is that the section is very confusing and has no structure. There's no flow and the lead sentence doesn't help the reader help understand what the section will be about. Jason Quinn (talk) 23:57, 15 November 2012 (UTC)
replies: text: Many thanks Jason. I've tried to simplify the whole section keeping references. Please revert if any worse, and be kind if I made mistakes. Edouard Albert (talk) 13:37, 18 November 2012 (UTC)
thread_title: Question about the meaning of the [[Tetrachromacy#Insects|'''Insects''']] section

message: IF A PERSON, LIKE MYSELF, WHO COMES FROM A LONG LINE OF MOSAICS, WITH AB CIS BLOOD AND TETRACHROMACY, RECOMBINATION OF CHROMOSOMES WITH X INACTIVATION, COULD PRODUCE SOMEONE WITH AN EXTRA RED CONE AND SOME ABILITY TO SEE INFRARED.  ----REBECCA LUNSFORD ANDERSON  — Preceding unsigned comment added by 68.7.130.72 (talk) 00:53, 15 January 2014 (UTC)
thread_title:  X INACTIVATION AND TETRACHROMACY 

message: So I'm wondering why that section is called "Possibility of" human tetrachromats? Isn't the section naming a confirmed case already?
And AFAIK there are other cases which aren't mentioned there such as Concetta Antico.
Please look up:
* http://www.popsci.com/article/science/woman-sees-100-times-more-colors-average-person (note that I don't know if that's just a publicity stunt or actually confirmed - I guess someone got to validate it)
* http://www.bbc.com/future/story/20140905-the-women-with-super-human-vision
* http://www.tenthousandthings.info/#!research-papers
* http://www.imbs.uci.edu/~kjameson/jamesonOUP3.pdf
and change that section's title and content as appropriate.
--Fixuture (talk) 23:01, 2 May 2015 (UTC)
thread_title:  "Possibility of" human tetrachromats? -> Aren't there confirmed cases? 

message: Used the value 3,790,000 as male population which is slightly larger than actual population. This will skew my results and give me a larger percentage of males with multiple X chromosomes. - 3,790,000/500=7,580 in higher population estimate and 3,000,000/500=6,000 in lower population estimate.
Types of males with multiple X chromosomes are XX, XXY, XXXY/XXYY, and XXXXY. Supposedly XXXXXY is possible but couldn't find any known cases or frequency related to male births.
For types that have ranges for birth frequencies I'm using the end of the range that will result in the most amount of males with condition. This will produce a higher number of males with multiple X chromosomes. Ultimately this will mean I will end up with the highest possible number of males with multiple X chromosomes. - If frequency is 1 in 10 to 100 births, 1 in 10 would be 3,790,000/10=379,000 males while 1 in 100 would be 3,790,000/100=37,900 males.
XX males - 1 in 20,000 to 25,000 births or approximately 189 males - 3,790,000/20,000=189.11
XXY males - 1 in 500 to 1,000 births or approximately 7,580 males - (3,790,000-189)/500=7,579.62
XXXY/XXYY males - 1 in 17,000 to 50,000 births or approximately 223 males - (3,790,000-7,580-189)/17,000=222.484
XXXXY males - 1 in 85,000-100,000 births or approximately 45 males - (3,790,000-189-7,580-223)/85,000=44.494
Total number of males with multiple X chromosomes are 8,037 males - 7,580+223+189+45=8,037
With a male population of 3,790,000 theoretically the most amount of males with multiple X chromosomes would be 8,037. This does not mean each one has tetrachromatic vision. Only that each individual has the potential to have 2 cones on 2 different X chromosomes giving them a total of 4 cones. However even individuals with 4 cones still don't always have tetrachromatic vision.
For the purpose of this demonstration let's imagine there's actually 10,000 males with multiple X chromosomes in a population of 3,790,000 males. This would mean that the percentage of males to possibly have tetrachromatic vision in the population would be at best .27% - 100/3,790,000*10,000=0.236852%
Basically it's absurd to think that up to 8% of males could have tetrachromatic vision.  — Preceding unsigned comment added by 66.87.80.157 (talk) 08:39, 24 March 2017 (UTC)
thread_title:  Up to 8% of males have tetrachromacy is absurd. It's incredibly unlikely to be more than 1% of males 

message: We will know better if we can find an actual human tetrachromat and test them.  There are people looking for them, but I expect that the search will be hard.  They might not see more colors, but rather better definition for the regular colors.  Where you or I might be able to distinguish between, say, ten shades of red, they might come along and be able to recognize a hundred, but they might still see them as shades of red, not some brand new octa-red.  At this point there are too many unknowns for us to really know.
Ken McE (talk) 21:21, 19 August 2018 (UTC)
thread_title:  Does functional Tetrachromacy really let you see 99 million more colors? 

message: The introductory paragraph currently says "In tetrachromatic organisms, the sensory color space is four-dimensional." It clarifies that this means "that to match the sensory effect of arbitrarily chosen spectra of light within their visible spectrum requires mixtures of at least four primary colors," but doesn't provide a direct source. But four points should only define, at most, a three-dimensional space, right? The trichromatic spectrum can be represented as a 2D triangle, and the dichromatic spectrum as a 1D line, so the tetrachromatic spectrum would be a 3D tetrahedron. Is this meant to include black as a point in the color space?  — Preceding unsigned comment added by 2600:6C4A:4C7F:FF9B:7951:AC53:29BB:FD23 (talk) 09:37, 17 October 2018 (UTC)
replies: text: Trichromatic spectrum cannot be represebted as 2D triangle. That is just a simplification by CIE without Y, real space is 3D. Valery Zapolodov (talk) 17:05, 24 March 2022 (UTC)
thread_title:  Four-Dimensional Color Space? 

message: Does they or related cells have any? We have only three special terms.
* Protan aka erythrolabe for red.
* Deutan aka chlorolabe for green.
* Tritan aka cyanolabe for blue.
But what about "special orange" of human tetrachromats, all those ultraviolet ones and so on, including mantis shrimp with more than a dozen types of cone cells? I couldn't find anything. - 109.252.81.3 (talk) 16:29, 23 November 2018 (UTC)
thread_title:  Extra photopsins names 

message: The content of pentachromacy is largely redundant with that of tetrachromacy, even after clean up. I propose merging them, i.e. adding pentachromacy (or multichromacy) as a subsection of tetrachromacy. Curran919 (talk) 17:22, 1 June 2022 (UTC)
replies: text: Seems fine to me (to be honest either way seems fine). If people have significantly more material to add about "multichromacy" (or the like) at some point in the future, the article can be re-split. –jacobolus (t) 21:10, 25 September 2022 (UTC)

text: Yes, do it. Dicklyon (talk) 21:12, 25 September 2022 (UTC)
thread_title: Merge with Pentachromacy

message: The title of the section  mentions "CVD", but there is no mention of "CVD" in entirety of the article. I checked the page history but still couldn't find the context behind it. Whoever added the acronym should have at least mentioned its full form.
Can someone please look into it?
Pinging active users: ,  —CrafterNova [ TALK ]  [ CONT ] 15:09, 28 September 2022 (UTC)
replies: text: I put in a new lead. Curran919 (talk) 16:17, 28 September 2022 (UTC)
replies: text: Thank you for the clarification. I really didn't know that CVD stands for color vision deficiencies —CrafterNova [ TALK ]  [ CONT ] 16:43, 28 September 2022 (UTC)
thread_title:  Tetrachromacy in carriers of "CVD" 

message: our brains synthesise myriad hues out of the three channels provided by the cones. It is tempting to speculate that the mantis shrimp with its 33 channels perceived so many more. However, its brain does not mix but keeps the channel apart. So in fact it only sees these 33 colours as discrete entities. 2A01:CB0C:CD:D800:80EC:E9D4:7AE5:C8EA (talk) 15:00, 19 August 2023 (UTC)
thread_title:  Mantis shrimp