Unlike dragons of Western lore, fearsome symbols of evil and chaos, the Chinese dragon represents nobility, wisdom and prosperity. Eastern dragons are intricately connected to the seasons and the elements and are often associated with one of the four cardinal directions. They also can be categorized by color, as each color bears a symbolic meaning and has associated connotations within Chinese culture.
Blue and Green
In Chinese culture, the colors blue and green are associated with nature, serenity, growth and health. Blue and green dragons symbolize the approaching spring, evoking the clear skies and new plants that the season brings. These colors also are representative of the East and indicate Eastern dragons. Other Chinese associations with blue and green include healing, rest, prosperity and harmony. In Chinese culture, there are four animals that represent the cardinal directions with the Green Dragon represents the power of the East.
Black and White
Black and white are key colors on the Chinese spectrum, representing the balance of the black yin, which is negative, passive and feminine, and the white yang, which is positive, active and masculine. Black dragons are associated with winter and the North, while white dragons represent autumn and the West. In China, the color white is associated with purity as it is in Western cultures, but it also symbolizes mourning and mortality, suggesting that the white dragon functions as an omen of death. The black dragon is known for its power and vengeance and is often connected to storms.
Yellow and Gold
Yellow dragons have been called “superior” and “the most revered of the dragons” because they represent the Emperor and the imperial family. Even in the 21st century, yellow is a color associated with solidity, reliability and warmth, and it is set aside for royalty and those of higher social class. Gold dragons share many of these assets and are recognized as symbols of wealth, wisdom and compassion. During the Chinese New Year holiday, the opening dragon dance begins with the arrival of a regal Golden Dragon held aloft by a group of men.
In China, red is the traditional color of good fortune and happiness, and it is often used in large celebrations, such as weddings. The red dragon is associated with luck, fire, passion and the heart. It is the dragon of summer and the South. Other Chinese associations with the color red include vitality, enthusiasm and creativity. During Chinese holidays like the Chinese New Year, a red dragon can be a focus along with equally lucky red envelopes of money.
Found at: Classroom.com
A campfire is magical. How the coals glow and the flames flicker and the sparks pop and shower, its mesmerizing. But, you can make it even more magical with these simple tricks. It will get old if you use these all the time, but an occasional surprise makes a campfire at that special place or time something to be remembered.
Adding a small amount of chemicals to a hot burning fire can have an ‘Ooooh-aaaah’ effect. It’s important to do these only after all cooking has been done on the fire and when there is little wind so the smoke can rise up rather than into campers’ faces.
You may acquire these chemicals in a grocery or dry goods store, in the laundry or cleaner section. Find copper sulfate in swimming pool supplies. Epsom salts, borax, and calcium chloride may be found with laundry/cleaning supplies.
Copper Chloride, Strontium Chloride, and others my be best found at fireworks supply companies. Practice before using them at a campfire so you know how much to use and how to best apply for maximum effect.
Creating Colors and Special Effects:
- Copper Chloride ~ BLUE flame
- Borax (laundry) ~ LIGHT GREEN flame
- Copper Sulfate (tree root killer for plumbers) ~ GREEN flame
- Strontium Chloride ~ RED flame
- Potassium Chloride (water softener salt) ~ PURPLE flame
- Calcium Chloride ~ BLUE flame
- Lithium Chloride ~ PINK flame
- Alum ~ GREEN flame
- Sodium Chloride (table salt) ~ ORANGE flame
- Magnesium Sulfate (Epsom salts) ~ WHITE flame
- Sugar ~ sprinkle into fire for TINY SPARKS
- Powdered Coffee Creamer ~ throw a handful into the flames above the fire for small SPARKLY FLASHES
- Flour ~ toss a small amount into flame to make a FLASH FLAME
- Iron filings ~ toss a small bit into flame to make GOLD SPARKS
- Powdered aluminum ~ toss a small bit into flame to make SILVER SPARKS
- Magnesium shavings ~ toss a small bit into flame to make very bright SILVER SPARKS
- VIOLET ~ 3 parts Potassium sulfate, 1 part Potassium nitrate (saltpeter)
So, then how do you get the chemicals into the fire? Well, throwing the powder in gives a burst of color, but then quickly dies out. You might want to do this for special effect when telling a story. But, to make the colors last longer, you can create wax patties. Don’t use these patties if you want sparks, just toss the dry chemical on.
How To Create Wax Patties
- Melt old candle wax in a double boiler.
- Get a bunch of small paper dixie cups.
- Pour about 1/4 inch of chemical into each cup.
- Pour melted wax into the cup to just cover the chemical and quickly stir it with an unfolded paperclip or other small stir rod. This is to thoroughly coat all the chemical.
Let thoroughly cool and then peel or cut off the sides of the paper cup. I leave the paper bottom on. Toss one of these patties into the hottest part of the fire and it will melt and the show begins!
Mixing different chemicals will not make a new color. Just add one single type at a time or put different kinds in different places.
From: Camp Fire Dude
It’s commonly believed that the ocean is blue because it’s reflecting the blue sky. But this is a misconception.
The ocean is blue because of the way it absorbs sunlight, according to the National Oceanic and Atmospheric Administration (NOAA).
When sunlight hits the ocean, the water strongly absorbs long-wavelength colors at the red end of the light spectrum, as well as short-wavelength light, including violet and ultraviolet. The remaining light that we see is mostly made up of blue wavelengths.
However, NOAA notes that the ocean may take on other hues, including red and green, if light bounces off objects floating near the surface of the water, such as sediment and algae.
Just how blue the water is depends on how much of it is available to absorb the light.
For instance, water in a glass is clear — there aren’t enough water molecules to really absorb the light.
But ocean water appears bluer the farther you travel down the water column. The water molecules absorb infrared, red and ultraviolet light first, and then yellow, green and violet.
Blue light is absorbed the least, giving it the greatest ocean penetration depth, according to NASA.
This fact is clear if you look at unedited underwater photos that weren’t taken with a camera flash or another artificial light source — even the most vibrant of tropical fish look blue.
Source: Live Science
In high-stakes politics and business, there are only two colors of ties: red and blue. Oh, sure, you might spot purple or yellow now and then, but those are clear statements of aloofness, be they calculated or careless.
Few world leaders or CEOs want to be seen as aloof.
But does it matter whether one wears red or blue? Yes, suggest several studies, including one published in the journal Science on Feb. 6, 2009. More on that in a moment.
First, some color:
During his first address to a joint session of Congress, President Donald Trump wore a blue and white striped tie. Seated behind Trump, Vice President Mike Pence and Paul Ryan, Speaker of the U.S. House of Representatives, both wore blue ties.
For his inauguration on Jan. 20, President Donald Trump wore a red tie with his dark suit, while outgoing President Barack Obama donned a blue tie. Their wives wore the reverse, with Michelle Obama in a red dress and Melania Trump wearing a powder blue ensemble.
In the first presidential debate of 2016, then-nominee Donald Trump donned a blue tie, while the Democratic nominee, Hillary Clinton, wore a red suit. The Democrats may have decided on “red” during the election, as Clinton’s running mate, Sen. Tim Kaine donned a red tie during the first vice presidential debates on Oct. 4, while Trump’s running mate, then-Indiana governor Mike Pence sported a blue necktie
In President Obama’s first 11 days on the job, he wore only red and blue ties, observed Daily News reporter Joe Dziemianowicz. “Obama represents something different in politics, but he dresses the same as everyone else,” said Esquire senior fashion editor Wendell Brown. “Washington, D.C., is a strange place when it comes to style. All the emphasis is on fitting in.”
At the inauguration in January 2009, Obama and Joe Biden seemed to coordinate efforts: “For the inaugural festivities, both executives chose predictable dark gray suits, white dress shirts, enlivened by either baby blue or red necktie,” wrote Lisa Irazarry of The Star-Ledger in New Jersey. “As Obama wore a blue necktie on Monday and Biden wore his blue Tuesday, maybe they prearranged not to duplicate each other alternating necktie colors.”
Former President George H.W. Bush and former first lady Barbara Bush both had on plum overcoats and purple scarves at the inauguration. They can be aloof now. Plus, purple is associated with royalty and we do tend to treat our former presidents as such.
Where’s all this come from?
The ties to red and blue go way back. Neckties are said to be descended from the cravat and used throughout most of history, at least the portion during which humans have been fully clothed. Blue was once associated with the blue blood of British nobility, while red represented the red blood of the Guards.
Red has long been associated with love. And there’s some science to that, too. A study last year found red clothes on women makes men feel more amorous towards them. In sports, athletes wearing red are known to outperform their opponents, in part because referees cut the red-clad competitors some slack, researchers discovered.
Politicians, of course, love to gain advantages. Neckties are one way they try to do that.
As Washington Post columnist Tom Shales wrote of a televised Bush-Kerry presidential debate in 2004: “Bush wore his traditional blue necktie, though a darker shade than the usual robin’s-egg hue, and Kerry wore the classic TV-red necktie; red ties supposedly lend color to the face of whoever wears them, and if there’s anything the Massachusetts senator needs, it’s color.”
But wait, there’s more.
Red and blue are also thought by psychologists to improve brain performance and receptivity to advertising. The 2009 study in Science supports this idea. It also suggests nuances that world leaders and presidential candidates might want to know about, assuming one buys into the notion that presidential messages and speeches are essentially a form of advertising.
The study found that red is the most effective at enhancing our attention to detail, while blue is best at boosting our ability to think creatively.
“Previous research linked blue and red to enhanced cognitive performance, but disagreed on which provides the greatest boost,” said study leader Juliet Zhu of the University of British Columbia. “It really depends on the nature of the task.”
Zhu and colleagues tracked the performance of more than 600 people on cognitive tasks that required either creativity or attention to detail. Most experiments were conducted on computers with a screen that was red, blue or white.
Red boosted performance on detail-oriented tasks such as memory retrieval and proofreading up to 31 percent more than blue. For brainstorming and other creative tasks, blue cues prompted participants to produce twice as many creative outputs compared with red cues.
Why? Look around.
“Thanks to stop signs, emergency vehicles and teachers’ red pens, we associate red with danger, mistakes and caution,” Zhu said. “The avoidance motivation, or heightened state, that red activates makes us vigilant and thus helps us perform tasks where careful attention is required to produce a right or wrong answer.”
And the value of blue?
“Through associations with the sky, the ocean and water, most people associate blue with openness, peace and tranquility,” says Zhu, who conducted the research with UBC doctoral candidate Ravi Mehta. “The benign cues make people feel safe about being creative and exploratory. Not surprisingly it is people’s favorite color.”
Perhaps presidential candidate’s choice of red vs. blue neckties should be made more thoughtfully than they realize.
Source: Live Science
We see a blue sky, because of the way the atmosphere interacts with sunlight.
White light, including sunlight, is made up of many different colors of light, each with its own corresponding wavelength.
Several different things can happen when this light encounters matter.
For instance, if sunlight passes through a transparent material, such as water, those light waves will refract, or bend, because light changes speed as it travels from one medium (air) to another (water). Prisms break up white light into its constituent colors, because different wavelengths of light refract at different angles — the colors travel at different speeds — as they pass through the prism.
Alternatively, some objects, such as mirrors, reflect light in a single direction. Other objects can cause light to scatter in many directions.
The blueness of the sky is the result of a particular type of scattering called Rayleigh scattering, which refers to the selective scattering of light off of particles that are no bigger than one-tenth the wavelength of the light.
Importantly, Rayleigh scattering is heavily dependent on the wavelength of light, with lower wavelength light being scattered most. In the lower atmosphere, tiny oxygen and nitrogen molecules scatter short-wavelength light, such blue and violet light, to a far greater degree than than long-wavelength light, such as red and yellow. In fact, the scattering of 400-nanometer light (violet) is 9.4 times greater than the scattering of 700-nm light (red).
Though the atmospheric particles scatter violet more than blue (450-nm light), the sky appears blue, because our eyes are more sensitive to blue light and because some of the violet light is absorbed in the upper atmosphere.
During sunrise or sunset, the sun’s light has to pass through more of the atmosphere to reach your eyes. Even more of the blue and violet light gets scattered, allowing the reds and yellows to shine through.
Source: Live Science
- Truth and the Intellect
- Piety and Contemplation
Blue is the color of the Heavens and is related to the fifth Chakra. Blue is traditionally worn by the Virgin Mary, the very embodiment of all the qualities described above. Whereas the reds, oranges and yellows carry with them a carnival atmosphere, blue is more sober, even somber despite its many variations.
If we’re “feeling blue” then we’re depressed or melancholy. And yet the bluebird is a universal symbol for happiness. The color has even given its name to a rich vein of music. The “blues” actually refers to “blue notes.” These are notes, either sung or played, that are pitched down a little for expressive purposes. An example is Billie Holiday’s heartbreaking rendition of “Strange Fruit.”
There’s something cool and detached about blue that gives rise to its reputation for spirituality and chastity. Above all blue is the color of the sky. Like the sky, blue is infinitely spacious. It contains everything, and yet contains nothing. The color is therefore associated with ideas of eternity.
In Jewish tradition the city of Luz, where the Immortals live, is also called The Blue City. Similarly, the mythical sacred mountain of the Hindus, Mount Meru, is constructed entirely of sapphire on its southern face and it’s this that is said to tinge the skies with blue.
To put any color out of context can have an alienating and often frightening effect. Knowing this, early British warriors daubed themselves in woad. These blue-skinned savages must have been an alarming sight for Roman soldiers.
To do something “once in a blue moon” is to do it very rarely. The phrase refers to the appearance of a second full moon within a calendar month, which actually happens about every thirty-two months.
Members of the aristocracy or the royalty are described as having “blue blood,” but why? The phrase originated with the Spanish, sangre azul, and refers to the pale-skinned Castilian ruling classes who prided themselves on never having interbred with darker-skinned races. Therefore, their blue veinous blood was plainly visible underneath the surface of their skin. There’s even a particular shade of blue that is meant to represent this color, called Royal Blue.
Blue is one aspect of the Hindu legend of Krishna that has remain unchanged through time and geography. We look at what this “blue magic” is all about, and why even Krishna’s sworn enemies were irresistibly drawn to it.
Blue is the color of all-inclusiveness. You will see in the existence, anything that is vast and beyond your perception generally tends to be blue, whether it is the ocean or the sky. Anything which is larger than your perception tends to be blue because blue is the basis of all-inclusiveness. It is based on this that so many gods in India are shown as blue-skinned. Shiva has a blue skin, Krishna has a blue skin, Rama has a blue skin. It is not that their skin was blue. They were referred to as blue gods because they had a blue aura.
All around the world, baby boys are dressed in blue. This originates in the belief that evil spirits congregate around newborn babies. Fortunately, these spirits detest the color blue, as it deprives them of their power. Consequently, dressing a baby boy in blue provides him with protection at a time when he is totally vulnerable. Blue was also considered an effective way of averting the evil eye.
Back then, girl babies were not considered to be as important as boys, and weren’t given any protection. Eventually, times changed, and girls were given the color pink.
Other meanings associated with the color blue:
- Navy blue and white, when used together, often represents sailing, and sailors.
- The saying “out of the blue” is used in reference to something unexpected.
- The expression “singing the blues” references a person who is complaining about their circumstances.
- The phrase “true blue” stands for someone who is loyal, trustworthy, and faithful.
- The saying “baby blues” is used to describe the sadness that women feel after giving birth. It is often used in reference to post-partum depression.
- A “blue ribbon” represents the best, first place, top prize, or number one.
- The expression “into the blue” means entering the unknown or uncertainty, not knowing what you’re walking into.
- The phrase “blue Monday” means feeling sad, often the feelings experienced when the weekend is over and the workweek begins.
- The term “blue laws” refers to laws that were originally passed to enforce specific moral standards.
- The saying “blue language” refers to using profanity.
- The “Bluebook” is known as a register of people of significance in social standing. Later, the term Bluebook was adapted by the car industry as the name of the registry listing vehicle values.
Borrowed from Sigils, Symbols and Signs
I found almost nothing in the way of foods that are naturally a turquoise color. This is what I did find:
Lingcods are sometimes found with amazing, edible blue flesh. A bile pigment called biliverdin seems to be the cause, but exactly how it gets into the flesh of the fish remains a mystery. Cooking destroys the color, but if you are wanting to eat a turquoise colored food, this seems like a possible choice.
There is also a chicken that lays blue or turquoise eggs. It’s called an Araucana. Here’s a picture of the eggs, and yes, they are real. When you crack them open, they look like any other egg.
Here’s a picture of the breed of chicken that lays these eggs:
“Oh yes! He loved yellow, did good Vincent… When the two of us were together in Arles, both of us insane, and constantly at war over beautiful colors, I adored red; where could I find a perfect vermilion?” ~Paul Gauguin
Most of us have a favorite color. Maybe you’re drawn to sky blue because it makes your eyes stand out or you find forest green particularly comforting. Whatever the case, your preferred hue can reveal a lot about what makes you tick. And the same holds true for the people you date — you’d probably have a different impression of a date if he or she said, “My favorite color is yellow” versus “My favorite color is black.” That’s because color speaks a powerful, silent language.
What it represents: Ah, the color of passion, anger and high blood pressure. Red is a primal color. It represents primal urges, like lust (“I must have you now!”) and fury (you know the phrase “seeing red,” right?). Yes, red is a commanding color: think of how stop signs get you to halt in your tracks and how you stand back when a red fire engine goes whizzing by.
Understanding people who love it: They act — sometimes without thinking — on immediate desires. In fact, they’re usually the poster children for immediate gratification. It’s up to you if you go for it… or proceed with caution.
What it represents: OK, orange is not exactly the easiest color to wear and it’s not the most common favorite color, but guess what? Orange is as sensual as it gets. Orange is a mellowed red — and it takes primal, lusty urges and mellows them with a softer vibe. Orange is the color of early attractions, emotional responses, and inner magnetism. Oh, and one other thing: orange is also close to gold, the color of success and wealth.
Understanding people who love it: Someone who likes orange is alive with feelings, the ability to nurture, and can intuit a path to success. If your favorite color is orange, you don’t have an “off” switch when it comes to passion. This is all good stuff, but there’s nothing casual about the connections this kind of person usually forges.
What it represents: Yellow is the color of the sun, vitality, power and ego… but it’s not a great indicator of romance. Watch out for self-centered, “me first” energy when someone prefers yellow to the rest of the rainbow.
Understanding people who love it: If yellow is your favorite color, temper your use of the word “I” when you’re interested in someone else. You can come across as too ego-centric otherwise. Now, if you’re dating someone whose favorite hue is yellow, make sure to jump in and share stories about yourself, since this person may not give you much room.
What it represents: Here is the heart of the matter: green is the color of love. (It’s no coincidence that we make our money in the same color…) Green is the color of life and abundance — leaves, grass, plants — it’s all about growing, expanding, and living. So why don’t we give ferns instead of roses on Valentine’s Day? Because green is about expansive, humanistic love and acceptance, not bodice-ripping romance. What’s more, green is a nice-person color, a “do-gooder, be-gooder” kind of color. This person has a warm heart. Passion is probably in there somewhere, buried under their integrity and honor.
Understanding people who love it: If you love green, you put the greater good before your own good — but try a little selfish behavior once in a while.
What it represents: Blue is a color of clarity, communications and charm. And regardless of the shade, this hue says: “I like to be understood.” On the downside, under stress, a “blue” person can send mixed messages, have trouble making up their mind, or just space out during conversations.
Understanding people who love it: If blue is your favorite color, you never run out of anything to say — expression is your strong suit. And if you’re dating a “blue” person? The same holds true; you should always know where you stand.
What it represents: Purple evokes the energy of illusion, imagination and fantasy. Or should we say purrrrple? Purple tends to inspire coyness, romance, flirtation and teasing — it builds anticipation with a dash of playfulness. The downside of purple is unrealistic expectations. Is it easier to live in your fantasy world than the real world? Some purple-lovers prefer it.
Understanding people who love it: If you love purple, you can be an imaginative romantic or prefer imaginary romance, depending on how you feel.
What it represents: White is light — the combination of all colors. White symbolizes purity (the traditional bridal dress, the christening gown) and spirituality. There’s a simplicity to it, too.
Understanding people who love it: People who love white are probably clean and orderly. While white isn’t the sexiest color, it is certainly healthy.
What it represents: Like white, black is a combination of all colors, but instead of purity, it represents the unknown, the unseen — mystery. Black basically holds back information… but there’s no denying that it has strong associations in our culture with “the dark side” and evil.
Understanding people who love it: If your favorite color is black, you are more hush-hush than high-strung in nature. The silence of this color lets others fill in the blanks. Black says, “I’m not telling you anything.” People who love black can be tough nuts to crack, but quite possibly worth the effort.
From red to blue to violet, all the colors of the rainbow appear regularly in urine tests conducted at hospital labs.
The prismatic pee collection seen in this stunning photo took only a week to assemble for medical laboratory scientists at Tacoma General Hospital in Tacoma, Wash. Heather West, the laboratory scientist who snapped the picture at the hospital, said she and her colleagues collected the urine colors to highlight their fascinating behind-the-scenes work.
“My picture was intended to illustrate both the incredible and unexpected things the human body is capable of, the curiosity in science, and also the beauty that can be found in unexpected places,” West said. “A mix between art and science.”
None of the urine samples were treated with chemicals in the lab to change their hue, West said. “When I posted the picture [on Flickr], people thought that we did something magical to it. They did not believe it was actually urine,” she said.
Hospital labs are often tucked away in a windowless basement, but they play a critical role in patient health. West, 26, who works the night shift, said a love of science and a wish to work in the medical field drew her to the career. “We are impacting every patient that comes into the hospital in multiple ways,” she said.
While the chromatic colors of pee are amazing, doctors are usually more interested in the contents of urine. Only a few colors, such as red or dark brown, warn that something is wrong with a patient’s health.
“I wouldn’t generally just monitor the color of someone’s urine,” said Kirsten Greene, an assistant professor of urology at the University of California, San Francisco. “But if it’s red or bloody, that’s a really strong cue that there’s infection or cancer, and that’s the one I would worry about the most.”
Here are some of the reasons for the pee shades.
Blood is the most common cause of red urine, and is a definite health warning signal. “As a urologist, I’m always worried when people have red urine,” Greene said. Bladder cancer, infections and kidney stones can all cause bleeding that shows up in urine, and all are worth a trip to the doctor.
More benignly, eating a lot of beets can turn your pee pink.
Dark-colored urine also points to health problems. Liver cancer can cause dark brown urine, containing excess bilirubin, a brownish pigment produced by the liver.
A drug called phenazopyridine (Pyridium) created the bright orange urine seen in West’s photograph. It’s a painkiller given to people with urinary tract infections, and converts pee into a Gatorade-like color.
“Antibiotics often alter urine color to orange,”Green said. “People who eat enough carrots to turn their skin orange can have orange pee, too,” she added.
Many people have seen the effects of dehydration on pee — a dark yellow- colored urine. Without enough water, a pigment called urochrome becomes more concentrated in urine.
On the other hand, in hospitals, some patients on intravenous fluids are so hydrated they produce nearly colorless urine, West said. The cloudy, yellow urine in West’s picture was caused by an infection.
Green urine usually flows from dilution of blue urine, as in West’s image. Occasionally, a urinary tract infection may trigger green pee.
The rarest of all on the pee rainbow, blue urine often comes from chemicals and drugs given to patients. The No. 1 offender is a drug called methylene blue, used to treat carbon monoxide poisoning, and as a dye during surgery. It makes the blue and green urine seen in West’s photograph.
Methylene blue was also a malaria treatment during World War II. Other medications that make blue urine include Viagra, indomethacin and propofol — the anesthetic drug infamously linked with Michael Jackson’s death.
Genetic conditions that affect the breakdown of dietary nutrients can also cause blue urine. Even blue food dyes sometimes passes into pee.
Indigo and Violet
In this photo, the deep purple urine comes from a patient with kidney failure. “The dark black one is something that you usually see in kidney failure,” West said. “Your kidneys should be filtering your blood and getting rid of your waste, and when you damage the kidneys, there’s a lot more blood [in the urine],” she said.
Another violet venue: Patients with catheters can develop a rare complication called “purple urine bag syndrome,” linked to a urinary tract infection and highly alkaline urine. A genetic condition called porphyria may also trigger deep purple pee.
The earliest life on Earth might have been just as purple as it is green today, a scientist claims.
Ancient microbes might have used a molecule other than chlorophyll to harness the Sun’s rays, one that gave the organisms a violet hue.
Chlorophyll, the main photosynthetic pigment of plants, absorbs mainly blue and red wavelengths from the Sun and reflects green ones, and it is this reflected light that gives plants their leafy color. This fact puzzles some biologists because the sun transmits most of its energy in the green part of the visible spectrum.
“Why would chlorophyll have this dip in the area that has the most energy?” said Shil DasSarma, a microbial geneticist at the University of Maryland.
After all, evolution has tweaked the human eye to be most sensitive to green light (which is why images from night-vision goggles are tinted green). So why is photosynthesis not fine-tuned the same way?
DasSarma thinks it is because chlorophyll appeared after another light-sensitive molecule called retinal was already present on early Earth. Retinal, today found in the plum-colored membrane of a photosynthetic microbe called halobacteria, absorbs green light and reflects back red and violet light, the combination of which appears purple.
Primitive microbes that used retinal to harness the sun’s energy might have dominated early Earth, DasSarma said, thus tinting some of the first biological hotspots on the planet a distinctive purple color.
Being latecomers, microbes that used chlorophyll could not compete directly with those utilizing retinal, but they survived by evolving the ability to absorb the very wavelengths retinal did not use, DasSarma said.
“Chlorophyll was forced to make use of the blue and red light, since all the green light was absorbed by the purple membrane-containing organisms,” said William Sparks, an astronomer at the Space Telescope Science Institute in Maryland, who helped DasSarma develop his idea.
Chlorophyll more efficient
The researchers speculate that chlorophyll- and retinal-based organisms coexisted for a time. “You can imagine a situation where photosynthesis is going on just beneath a layer of purple membrane-containing organisms,” DasSarma told LiveScience.
But after a while, the researchers say, the balance tipped in favor of chlorophyll because it is more efficient than retinal.
“Chlorophyll may not sample the peak of the solar spectrum, but it makes better use of the light that it does absorb,” Sparks explained.
DasSarma admits his ideas are currently little more than speculation, but says they fit with other things scientists know about retinal and early Earth.
For example, retinal has a simpler structure than chlorophyll, and would have been easier to produce in the low-oxygen environment of early Earth, DasSarma said.
Also, the process for making retinal is very similar to that of a fatty acid, which many scientists think was one of the key-ingredients for the development of cells.
“Fatty acids were likely needed to form the membranes in the earliest cells,” DasSarma said.
Lastly, halobacteria, a microbe alive today that uses retinal, is not a bacterium at all. It belongs to a group of organisms called archaea, whose lineage stretches back to a time before Earth had an oxygen atmosphere.
Taken together, these different lines of evidence suggest retinal formed earlier than chlorophyll, DasSarma said.
The team presented its so-called “purple Earth” hypothesis earlier this year at the annual meeting of the American Astronomical Society, and it is also detailed in the latest issue of the magazine American Scientist. The team also plans to submit the work to a peer-reviewed science journal later this year.
David Des Marais, a geochemist at NASA’s Ames Research Center in California, calls the purple Earth hypothesis “interesting,” but cautions against making too much of one observation.
“I’m a little cautious about looking at who’s using which wavelengths of light and making conclusions about how things were like 3 or 4 billion years ago,” said Des Marais, who was not involved in the research.
Des Marais said an alternative explanation for why chlorophyll doesn’t absorb green light is that doing so might actually harm plants.
“That energy comes screaming in. It’s a two-edged sword,” Des Marais said in a telephone interview. “Yes, you get energy from it, but it’s like people getting 100 percent oxygen and getting poisoned. You can get too much of a good thing.”
Des Marais points to cyanobacteria, a photosynthesizing microbe with an ancient history, which lives just beneath the ocean surface in order to avoid the full brunt of the Sun.
“We see a lot of evidence of adaptation to get light levels down a bit,” Des Marais said. “I don’t know that there’s necessarily an evolutionary downside to not being at the peak of the solar spectrum.”
Implications for astrobiology
If future research validates the purple Earth hypothesis, it would have implications for scientists searching for life on distant worlds, the researchers say.
“We should make sure we don’t lock into ideas that are entirely centered on what we see on Earth,” said DasSarma’s colleague, Neil Reid, also of the STScI.
For example, one biomarker of special interest in astrobiology is the “red edge” produced by plants on Earth. Terrestrial vegetation absorbs most, but not all, of the red light in the visible spectrum. Many scientists have proposed using the small portion of reflected red light as an indicator of life on other planets.
“I think when most people think about remote sensing, they’re focused on chlorophyll-based life,” DasSarma said. “It may be that is the more prominent one, but if you happen to see a planet that is at this early stage of evolution, and you’re looking for chlorophyll, you might miss it because you’re looking at the wrong wavelength.”
- Violet vs Purple In the traditional color wheel used by painters, violet and purple are both placed...
- Foods That Are Turquoise I found almost nothing in the way of foods that are naturally a turquoise color. This...
- Best colors for a closet You may not give much thought to the inside of your closets when painting a room bu...
- A to Z Healing Index Here is an A to Z list of illnesses and the colors that are used to treat them. C...
- Purple Planet Earth The earliest life on Earth might have been just as purple as it is green today, a...
- Healing Colors Healing with color requires a basic understanding of the specific function of a parti...
- The Colors of Hinduism Hindu deities are depicted in colors that symbolize many positive attributes. Rem...
- Designing With Turquoise A mix of blue and green, turquoise has a sweet feminine feel while the darker teal...
- The Psychology of Yellow Some of the key characteristics that are often associated with the color yellow i...
- Chinese Dragons and Color Unlike dragons of Western lore, fearsome symbols of evil and chaos, the Chinese dra...