I just got to thinking—I love watching The Universe, How the Earth Was Made, etc…and I remember arguing with Don Wollheim about the origin of flowers and colors (two separate debates, actually.) Today I’m thinking about color, and the tendency of many biologists to assume color perception had to do with mating display.
I don’t think so. I think the first ‘color’ other than white, black or brown, was red.
Why? Because in the deep sea, it’s a great advantage to be red if you’re not going to be transparent. You’re invisible. And many modern (but ancient) deep sea creatures are red…the vampire squid. etc.
The first evolution of sight was the ability to perceive light and dark and react to it. Since many corals have photosynthetic elements (zooxanthellae) that give them sugars via sunlight, I’d think that the ability to crawl into a sunnier spot (and many soft corals crawl, or grow ot a certain side)—is advantageous. It likely started because, like the little robot, things need input—in this case—of energy.
There followed the development of the ability to see motion. Many primitive creatures still register only movement against a still field. If you aren’t moving, you’re not there.
From that, the primitive brain developed the complexity to ‘expect’ or ‘track’ that movement and ‘store’ the position to track it down. Predictive tracking requires a few more dedicated neurons.
Beyond that I think camoflage became big business. The ability to look like your background.
I think red was the first ‘color’, and it was a protective pigmentation. I have a red coffee cup…and if I set it down in the darkened kitchen, I need to find Marvin the Martian’s eyes, because the red cup is just not visible. It’s no-color. It’s not there. And it’s not just my aging eyesight.
Redness developed in, I think, the early, early ocean. And when redness came up into the sunlight…predators found it advantageous to see red. Ergo (and we can’t prove this, since soft tissue doesn’t fossilize) the first development of color vision would have have come along as an evolving system for detecting red.
Genetics is a crap shoot. You tweak one thing and a dozen others tag along and get tweaked with it. Develop red, and pretty soon you’ve got weak red (pink) and then the zooxanthellae and their photosynethesis give you greens. And then you get some strange chemistry combos through mutation and you’ve got a yellow. If you’re a coral nibbler, seeing some of these wavelengths is good. Now—we’re not always talking 20/20 vision here…and there’s the possibility of creatures seeing way over into spectra we don’t visit…eg, insects picking up uv. [Jane and I have had interesting arguments as we drive regarding how we see certain landscape, what predominates, and we’ve decided she sees more blue than I do. I think humans do see a bit into the high and low edges of the spectrum.)
I also think that colors in their origin are about biochemistry. There’s something in the makeup of flowers that makes yellow and purple ‘popular’ colors. Blues are hard to get—in flowers. Not hard in birds. and I think it’s about life process, chemicals of a certain sort in abundance: for instance, stony coral slurps up calcium and magnesium by the tablespoonful and builds what we call bone. In fact—animals (and corals are animals) are really fond of calcium (which not only builds our bones but powers our contractile tissue.) But plants—are really fond of phosphate and nitrogen—which in general, animals don’t like to bathe in. And we’re not green, and plants are. Its that chlorophyll thing—but it’s also what lives inside your skin, whether you have hemoglobin, and whether or not you were up near the primeval surface collecting light and making sugar, or down in the depths either trying to be red or to find what IS red. If our ‘blush’ hadn’t been an advantage, the survivors would have been the ones with thicker skin.
So there. I don’t think it’s mating displays, well, not for millions of years. I think it’s survival.
Or being able to survive until you can mate. The stillness notion is interesting coz the first thing I thought of has to be one of the most basic instincts — don’t move and it won’t see you. The red issue is really interesting and one I now wanna play with myself. I’ve wondered about flowers, how in general wildflowers (and most flowering bushes too, at least in the southwest) tend to be more yellow and oranges than other colors, but hummingbirds really zero in on reds. I’ve had them buzz my red Escape at home and at work a lot.
On a side note, saw an article the other day that hawks focus on the odd floored prey, which made me think of the light vs dark colored moths in industrial England — a big evolutionary example in my day.
I saw a hummingbird the other day checking out a walk/don’t walk sign. It was in the ‘don’t’ phase: red lights!
I think a lot of these things got started as survival first, display later. After all, what’s the point of a display unless it shows the potential mates how immensely fit one is?
As for eyesight, I’m pretty sure that bees see into the ultraviolet, and some flowers have more ‘color’ there than in the visible range. Which brings up the issue of human-centric measures of ‘visible range’…
Colour as we see it, especially for flowers, is a side-effect of the main purpose, which is to be attractive to their pollinators. When examined under UV, patterns that are invisible to us become clear, often of the “this-way-to-food” signs. Some of the more complex examples consist of what can only be described as landing strips with directional arrows.
Ancient pigments are starting to be found preserved on some quite early fossils The problem being that is the range of colours limited or is it just that certain ones preserve better.
BBC had a little taster article on this at the end of last year : http://www.bbc.co.uk/news/science-environment-14933298
My modem will shut me down in 15 minutes–a protective measure, you understand–so I have to make this quick.
Of course when it comes to color we first always have to ask if we’re talking transmitted or reflected light. But if I may take as an example a red squirrel fish in the ocean where red light is filtered out at depth, hence the upper waters appear blue, and on the surface the red squirrel fish is red because its skin absorbs green and blue wavelength, then at depth where there is no red light to reflect and the skin absorbs blue, the fish should appear black. If seen from above looking toward the “inky depths” that’s fine. But what if it’s in the upper waters and seen from the side? A “black” fish against the blue water should be visible.
Perhaps I’m not understanding the situation you envision?
Much of evolution being predator-driven, being less visible to some predators in some circumstances is still a quality that will be powerfully selected for, in the same way that being a little bit sensitive to light is eventually going to lead to the evolution of an eye, even if it is only one like the human eye, built backwards and never would have been built that way by an intelligent designer …
Just after I read your post, I then came across this article about “Monet’s Ultraviolet Eye” http://www.downloadtheuniverse.com/dtu/2012/04/monets-ultraviolet-eye.html
It suggests that human eyes can detect ultraviolet, but that our lens normally filters it out. So when Monet had his lens removed as a form of cataract treatment, his paintings started showing things that are only visible in ultraviolet.
Interesting. A cardinal in a cedar tree is hard to spot unless you’ve trained your eye to spot them.
From what I’ve read, dogs see yellows, blues and purples, but not red or green. That seems counterintuitive if you think of canines hunting — vegetation and blood would look grey and blend in with what you’re hunting. What’s the advantage of seeing yellow and blue? On the other hand, prey animals may have evolved to avoid being colors predators can see.
There was a park in Missouri that stocked their pond with rare golden trout. Within a week most were lunch.
It’s ‘saturation’. The neural transmission temporarily ‘wears out’ on a certain wave length…sort of like the dog smelling the daisy in the post I made today. If our nerves didn’t ever flag on anything I think we’d be motionless, just little lumps of sensation overwhelmed by the input.
It’s why you need to change coffee or tea types every few days to be able to taste it—why you may not realize the cat litter needs changing—why your SO walks in as you’re painting or sanding and says, “Good grief! Why aren’t you wearing a mask?”
The receptors for vision, taste, and smell have a limited chemical ‘charge’ and when it runs out, chemically goes to zero state, it takes a while to recharge or re-set. That’s why when you’re buying cologne, or testing for taste, you may need to ‘clear your palate’ with a different scent or taste.
Fortunately the sensors that advise us of pressure and heat are more direct, and more energetic or we’d fall on our noses from balance failure or go on hanging on to that hot pot handle til we fry ourselves.
You run into this with people who wear a lot of perfume or cologne too. They keep adding it on until *they* can smell it, repeatedly throughout the day, not realizing that everyone else can smell them from twenty feet away. And for those of us who get migraines from the stuff, it can get to be a real problem.
In human eyes, IIRC, red and green are seen by one type of ‘cone’ cell, and blue and yellow by another. That’s why looking at a green light leaves a red afterimage, and looking a something bright yellow for a while leaves a blue afterimage. This might (I’m not a biologist!) have something to do with why losing or not developing green colour vision also means no red colour vision, if there is a strong bio-chemical reason for this paired sensitivity.
In that case, maybe ‘graying out’ the green background so other things stand out strongly might have an advantage that is strongerthan being able to see red blood among the green. Especially as I’ve occasionally heard that red-orange is somehow supposed to be a good colour for hiding among greenery, citing tigers and orang-utans as exapmles. I’m not sure about that – maybe if all the cone-cells are overexited by all that greenery they haven’t got enough to spare for seeing the red bits inbetween???
As for the ‘visible spectrum’, and the effect of the grayed-out green background, I remember something from a David Attenborough series about birds. He talked about a kind of small hawk or kestrel or some such, whose favourite prey was a specific kind of fieldmouse. The hawk didn’t see green, but it could see into the ultraviolet spectrum a bit, like bees as Apf said (and David Attenborough showed on another program about flowers). It turned out the little fieldmouse leaves a trail op urine spots that show up under ultraviolet as bright blue spots, very visible against the gray background. The hawk could easily follow the trail in the direction in which it became brighter, and find the mouse at the end of it. Much easier than finding a dun-brown spot against a green-with-occasional-brown-spots background.
Several other kinds of birds also could see ultraviolet, but definitely not all of them. I think one of the ones that could, was a relatively drab (to our eyes) bird of paradise (or maybe a kind of bower bird), which turned out to be brilliantly coloured in UV – in that case it seems more like a sexual selection thing, rather than the survival-based development in the little hawk.
There is so much variation in nature, and still so much to discover that people have never even thought about being possible. I really loved those programs.
Speaking of colors, just saw this on Smithsonian channel. Extremely interesting, especially about skin color the trade off of UV protection for folate levels in the blood, and vitamin D manufacturing as evolutionary pressures on skin color.
http://www.smithsonianchannel.com/site/sn/show.do?show=141379
I was under the impression that cats also only see yellows and blues, and that they sacrificed green/red color vision and the ability to pick things out from a background in favor of night vision and enhanced ability to detect motion. — the minute the ball stops rolling, they lose it. The “stop action” movements of squirrels always fascinates me in that context.
In ref: Flowers and ultraviolet light, see: http://www.naturfotograf.com/UV_flowers_list.html
It’s worth mentioning too that our own ability to discriminate color has been enhanced by civilization.
The Greeks had fairly few colors. Many ancient languages have limited palettes.
In Latin, I can just about reel off what there is in a few lines.
In 1856, a chap discovered a purple dye, mauvine. This began the modern dye industry—and people exposed to the modern dyes have trained their brains to recognize a more finely defined spectrum.
It’s an urban legend that women see more colors than men. If that were so, male painters would be at a complete disadvantage. Those of us who have a complete range of color vision can learn to do it. The question is more cultural—ie, am I interested in the difference between daffodil and crocus? Go to the paint department of your local hardware. Do you see differences in the shades? If you’re a painter or a home decorator, yep, betcha. Now, as above, Jane and I do seem to differ in how far into the ‘unseen’ spectrum we do see—which can certainly speak to differences in what colors we ‘like’ or how we would paint a scene if both of us were painters. What a painting does, as opposed to an unaltered photograph, is play deliberate games of perception, bringing the unseen color ranges into the range of most viewers, exaggerating textures, etc, in a pleasing or evocative way.
And for those of you curious: the Latin colors. http://coolschool.k12.or.us/courses/121510/lessons/assignments/13/13-4.latincolor.html BUT just like the guy who’s never trained his brain—most Romans would be completely puzzled by this list and many would say they didn’t know certain words and were guessing. The colors they mostly referred to are: albus—opaque white; Rubens — transparent ruby red; sanguineus: blood red; rufus—reddish, red-brown; purpureus—[purple] Imperial purple, actually a violet on the very slightly red side [ http://en.wikipedia.org/wiki/Tyrian_purple ]; flavus: opaque yellow brown, blond; croceus—sunny transparent yellow; niger—opaque, flat black; nero—glossy black; ater—transparent black; caeruleus—sky blue. And you’ll notice (for us) an unusual precision in those colors…that you can talk about the night being ater, but never niger. A cat could be niger or nero depending on the quality of its fur. But if you used ater with the cat it would more describe his disposition.
Many languages have what we might consider ‘limited’ color words. Japanese, for instance, did not have a separate word for ‘green’, pre-Western contact (and for a good chunk post, too.) The word for blue, ‘aoi’, stands for the entire portion of the spectrum which a Westerner would term blue and green.
However, ‘sakura’, meaning cherry blossom, can be used as a color word, which only goes to show that though this culture does not put a premium on the difference between green leafies and blue whatever, it does on whether something is a pale pink or not.
Japanese has been changing under the influence of Western culture; it now uses ‘midori’ to mean green in some instances. Midori means grass. The word cannot be used as widely as a speaker of English would use green (I’m not clear on the exact parameters.)
There are other examples; some languages have three color words (usually black, white, and one other, such as red or yellow.) Others, such as our own, have a positive explosion of them. Neither case implies that one set of people sees color less; it does say a lot about the way a culture organizes its ideas and/or memes. There is so much variation between languages that the difference must be cultural, not biology.
Also, re: men not seeing as much color as women: not quite a myth. Men are more often red/green colorblind (by something like a factor of ten, which means most of you have probably met at least one such man, but likely have never met such a woman.) There’s a study out there looking at this and whether it means humans have three channel color vision (red, green, blue) or if some women might have four channel color vision (red, green, red/green, blue). It has to do with the way the genes for red and green are placed on the X chromosome, and if I go into the detailed explanation, your eyes will glaze over (if they aren’t already!) Basically, go look up ‘tetrachromat’ for the in-depth info, if you’re interested. Or go here: http://old.post-gazette.com/pg/06256/721190-114.stm –which is a fun write-up.
Odd fact re: tetrachromacy: a tetrachromat woman is more likely to have a red/green color blind son. How’s that for family friction?
Interesting–fwiw, I’m one of those red/green colorblind men, but it works in odd ways. I’ve struggled to find a red thing in green grass, but not for green things surrounded by red. Big red things are easy to find; small ones aren’t. And I’m a color photographer, and the condition doesn’t seem to limit me. (But maybe my pics look odd to others.)
I don’t have a reference handy, so take this with a grain of salt, but I read somewhere that color-blind men are better at seeing, say, the deer hiding behind those trees, than someone with regular vision.
I gather it’s a matter of recognizing shapes despite complex visual fields. Handy for hunting… I imagine it would be useful for photography, too. 🙂
Interesting re: your vision. I’ve met two colorblind men; one couldn’t tell red from green at all (a photo of a red rose with green leaves against a blue background looked uniformly brown against blue to him.) I gather that means he had a red/green cone, or maybe two red/green cones. You can tell the colors apart somewhat… maybe you have a green cone and a red/green one?
I just got back from teaching my Language & Society class and am reading on Wave without a Shore as a way of winding down. Among other things, tonight my students and I were talking about colors and language. Supposedly, all languages have a minimum of three color words: light/white, dark/black and red. (I certainly don’t know all languages and have seen a few linguists disagree with statement.) Red is also the first color a human child supposedly distinguishes other than light/dark.
Scottish Gaelic and other Celtic Languages do not traditionally distinguish between green and blue, at least as English does. I used to describe it as simply being a different division of the color spectrum (many languages have one word for blue/green), but now I think that they are partly categorizing based on how a color reflects/absorbs light. “Gorm” is traditionally translated as dark blue, but can also mean dark green or dark purple (and I wonder about dark brown). Uaine is a pallid, yellowish-green to English-speaking eyes, but seems more to be the color of young or dying vegetation that hasn’t darkened into full green yet. I think it reflects light well. Glas (etymologically related to our word Glass) is blue/grey: a whitish blue or gray range that my Puritan ancestors would recognize as a “sad” (not bright/reflective color). An example in a traditional adjectival phrase: A person who is racially, to North American eyes, “black” is described in Gaelic as “duine gorm” or “dark blue/skin that absorbs light” person. Gaels don’t traditionally categorize people by skin color (as Americans are enculturated to do), however, but by hair color: they have another set of color terms for that, not the above ones. Color and culture is really fun: I did a talk on it last fall.