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When the Earth Was Purple
Ollabelle writes "It's always been a bit of a mystery why plants absorb red and blue light, reflecting green, when the sun emits the peak energy of the visible spectrum in the green. A new theory offers one possible answer: that the first chlorophyll-utilizing microbes evolved to exploit the red-and-blue light that older green-absorbing microbes didn't use, eventually out-competing them through greater efficiency and the rise of oxygen."
The article mentions that when looking for life elsewhere in the universe, "We should make sure we don't lock into ideas that are entirely centered on what we see on Earth", suggesting basically that we don't just look for green plants, but accept that plants on other planets could be any color.
Duh.
I can't understand people who think that to find life on other planets we have to look for conditions similar to Earth. All of the hubbub over liquid water seems so silly to me. We have *no idea* what life on other planets might be like. I think that the only thing to look for is patterns which we don't believe could occur in nature, suggesting that the anti-entropy force of life might be present.
Anyway, I'm kind of a skeptic already, I don't think that looking for life outside our galaxy is particularly interesting or useful anyway, considering that the nearest life would be millions of years away by interstellar travel. Even if it's out there, we'll never meet it or communicate with it.
but they got too big and fat, so they all died and they turned into oil. And then the Arabs came and they bought Mercedes Benzes. And Prince Charles started wearing all of Lady Di's clothes. I couldn't believe it.
What?
would that fit with plants being green? It seems like it would if I'm understanding correctly.
Which reminds me of the theory that before the global flood (Noah's ark) most of the earth's water remained in the atmosphere. If the atmosphere was a super-thick water cloud it would make sense that the earth would be purple.
Green is the new purple, completly off topic but a scary resemblance.
You use the word theory. I don't think that word means what you think it means.
Slashdot - where whining about luck is the new way to make the world you want.
I don't buy into it because (a) these people aren't rational and (b) taking away their religion could make them worse - they could easily be converted into Stalinists or extreme nationalists. But I am sure that this, as well as the desire to get budget for exploration, is one of the factors in the search for life on Mars, and in SETI.
Finally, looking for water is not irrelevant. Any practical life form is going to need a solvent and carrier for the various chemicals it needs to get from place to place internally. Water is unique because its strong hydrogen bonding gives it a wide liquid temperature range. Other small molecules which are good solvents also tend to have very low boiling points, meaning that the range of reactions that can take place in them is much more limited. Water has very unusual properties, in fact, that make it more probable that life would evolve on a planet with lots of liquid water than, say, one covered in methane or liquid carbon dioxide.
Pining for the fjords
Specific wavelengths of light are required to kick the electrons in specific molecules into the required energy level... i.e. Plants are green because red & blue light is required for a successful sequence of highly specific chemical reactions.
It has nothing to do with total levels of energy absorbed from the sun, but the energy produced by the chemical reaction which is triggered by photons. Or, plants are powered by chemicals, not by heat.
Deleted
After watching Barney the Dinasoaur I think we were all able to infer that the earth was purple at some point in history.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
The original form of photosynthesis resulted in a different metabolic pathway which used red or blue light and evolution took care of the rest
There were some conditions on the Earth at that time which meant that only red and blue light was available at the intensities required.
There are many possibilities why this might be so, including the nature of the media in which the first synthesising bacteria lived. I suspect the explanation when it is eventually found will be very interesting. However, it is by no means obvious that there is not a much simpler photosynthetic pathway using a single photon absorbtion, and it did not evolve simply because the conditions at the time - the predominant biochemistry of the bacteria and the wavelengths of light falling on them - were not suitable.
Pining for the fjords
Noo!!
that whole Green Tentacle - Purple Tentacle thing again!
This is proof that the artist formerly known as the artist formerly known as Prince has been here on earth since the dawn of time!
You moved your mouse. Please restart Windows for changes to take effect.
Plants originated on a planet where the sun was a different colour (http://news.bbc.co.uk/2/hi/science/nature/6589157 .stm) and the hairdressers and telephone cleaners who colonized earth brought them here...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Can someone here afford a few hundred bucks from this scientist to replace his old computer with CGA video and monitor?
Wh47 d1d j00 541, 31337 15n't t3h r0xor5 ne m0r3???
I'm no scientist, so can somebody please explain the relationship between TFA and the article described here:
Plants may be red and yellow in galactic boonies
Frankly, the colour green was easier to understand when I didn't think about it...
Who can wait for the rise of (and the war between) the United Atheist Alliance, United Atheist League, and the Allied Atheist Allegiance? By all the Sciences, it will be a glorious day.
You know, there is a difference between trolling and pointing out the flaws in your reasoning. Just saying.
I see trees of purple , blue roses too
I see em bloom , for me and for you
And I think to myself , what a wonderful world
All the plants were split into two camps, Green! and Purple! They fought until there was only one kind left.
"Waste not one watt!" - CZ
This theory has been around for ages. Is the recent discussion of this because of a new development? I don't see it anywhere.
I think that the only thing to look for is patterns which we don't believe could occur in nature.
Because if you want to understand a process, and you have a fully functional model which uses that process right in front of your eyes, the smart play is to completely ignore that model, right?
I don't think that looking for life outside our galaxy is particularly interesting or useful anyway, considering that the nearest life would be millions of years away by interstellar travel. Even if it's out there, we'll never meet it or communicate with it.
And after all, any probes we might send would travel at the same speed as radio waves. I see your point. Life throughout the universe: utterly worthless and uninteresting.
Nope. Other shows have tried weird looking aliens. Adults seem to treat them like kids' shows, and lose interest. The thing is... most sci-fi isn't about science or aliens at all; they're just re-tellings of old human stories; those alien stories are just modern versions of ghost/demon/knight stories from millenia ago, that humans find appealing.
The problem is just that most of us simply CAN'T imagine life from other worlds.
No, it doesn't!
- Solar irradiance at sealevel
- Absorption-spectrum
Solar irradiance at sealevel 'peaks' at 470nm which is exactly where chlorophyl-B absorption peaks. In fact the 'peaking', when put into context, is somewhat vague, since throughout the whole visible spectrum from 400nm - 700nm you have well over 50% of the real watts that you get at the peak 470nm, so an adaptation to a particular wavelenght within it gives at most only a conservative if not marginal advantage.
www.tribalnetworks.org - helping tribal people around the world to own their own means of high-tech communications
However, your first comment appears to be made in ignorance of the recent discovery that there is more to it than that and that a kind of quantum channeling - which I don't pretend to understand - increases the chance that the blue-excited state will last long enough for the second step to have a good chance of occurring. The operative word was clever, not quantum.
As for your third point, you misrepresent what I said. Let's assume that a "2Y" process exists and works better than the "BR" process. How would an organism evolve to use it? Evolution is not like engineering development, where the decision may be taken to expend large amounts of effort on something that may not work. An organism which starts to develop a pathway that can use a single yellow photon will have nothing useful to do with it unless this meets a specific need that improves its fitness. Somehow we have to assume that a double process would emerge in a single step, along with all the other modifications to biochemical pathways that would need to exist around it. This is exceedingly improbable. Evolution does not, in fact, present any obvious mechanism for saltation. Hence the interest in research which explains how cetacean evolution resulted in flukes that beat up and down - because the growing tail worked alongside swimming legs and had to work in the same direction.
Pining for the fjords
Haven't you heard? Green is the new Purple.
The plants are green because of intelligent painting. The Intelligent Painter, (you know who, but who shall remain nameless due to legal reasons, wink, wink) said I give you green plants for food.. This unwarranted attack on religion by science is totally unwarranted. Here we are, with a perfectly good explanation of why plants are green. And out of nowhere these scientists come and explain it all in a logical and credible manner. Our God of the Gaps, oops sorry The Intelligent Painter is now diminished by that much. If this attack continues, we will have no choice but to invoke the "Protection of Endangered Species Act" and demand certain "gaps in knowledge" to be preserved for ever as the sanctuary for Intelligent Painter.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
I'm violet, da ba dee da ba dye!
Our light isn't mainly green, take a prisma there is more red and bleu then that thin yellow/green the plant absorbs what is most of and thus its pigments are good if ir reflect where there is less of.. green.
I know you're out there. I can feel you now. I know that you're afraid. You're afraid of us. You're afraid of change.
It's pretty obvious once you know the argument. It's due to light-scattering. There's so much energy in the sky all day that it doesn't matter what color you absorb, there's plenty at any visible wavelength. But during sunset and sunrise there's predominantly red light in the sky, and a green plant would be more efficient at absorbing red light (they're complementary colors) than if the plant were another color. This blog entry goes into it:
. view&FriendID=187945&blogMonth=9&blogDay=24&blogYe ar=2006
http://blog.myspace.com/index.cfm?fuseaction=blog
That's why I like what I've read (His Master's Voice, Solaris) of Lem's work. He admits that what we encounter "out there" is likely to be largely incomprehensible, and surely won't be able to be just rephrased as another human story.
keep your crack pipe topped up and it will continue to make perfect sense.
What if Tetris was invented by Nazis?
I just figured that the "intelligent painter" had a monopoly on this section of the universe and decided to paint plants green. It's not like he has much competition...
Or perhaps he owns patents on many other plant colors. The first green algae/plants were the only ones not smited out of existence.
I've known about this for at least 15 years, and I've never even studied biology, so I'm certainly not learning about it from cutting-edge sources. Considering the time it takes for ideas like this to percolate down to the layman, this news must be decades old.
I see that we either have 3 people with a warped sense of humor here on /. or 3 more morons than previously suspected. Who modded this 'Informative'? I could possibly have seen this modded 'Funny'.
The only Plasma Charges around the earth are on the Vogon Demolition Ships.
My layman's theory is that photosynthesis arose as a form of protection against the intense UV radiation that hit the earth in its early oxygenless (and therefore ozone layerless) period. Different pigments arose by chance, some more effective than others. The energy absoarbed by the pigments went to heat waste or broken down pigments until a pigment appeared that could pass on that energy in a useable form. The early atmosphere was probably reddish from the lack of blue scattering oxygen and from volcanic dust. So was is it more advantageous to try to capture the direct sunlight or the scattered sunlight? And maybe the green pigments were chemically better suited for the oxygenated atmospheres that developed.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
A plant's collecting light isn't anything at all like an animal foraging for food. And a biologist doesn't know this?
Oh wait, he's NOT a biologist. He's an astronomer and knows less biology than me, another layman. I suggest he stick to astronomy, and that the lame web site Live "Science" stick to quoting people who have actually studied in a field.
When they have a story about a black hole are they going to ask a biologist about its event horizon? Or maybe a cook at McDonalds, who is likely to be more knowlegable about the subject?
That's where I stopped reading. Lame!
-mcgrew
The problem with travel methods that let you go huge distances (wormholes, whatever, jolly fast stuff anyhow) is that they miss all the stuff between you and your destination.
Well I'm glad that the problem isn't something like, oh, I dunno, that those travel methods seem to defy physics, or something.
They're filming these on a studio lot. There are tons of idle cowboy, nazi, ancient greek, etc. costumes and sets available. It's an obvious cost-saving move. Not to mention it taxes the writer's brain a lot less to rip off these plotlines.
That's part of why I loved Star Trek. Where else could you see all the different genre prope in the same series?
Man, you really need that seminar!
There is no right to feel safe thru security vaudeville at the expense of everyone's freedom, privacy and tax money.
Red and green aren't complementary colors in the light spectrum, they're both primary colors.
Red and green aren't complementary colors *period*. The Red-Yellow-Blue spectrum still taught to children and art students is simply incorrect, and the mixing of different ratios of "complementary" colors to get black is just a hack atop a poorly designed system. (And I say this as someone with an art degree, so don't think I'm bashing on art students here).
The additive primaries ("in the light spectrum" as you said) are red, green, and blue.
The subtractive primaries (as useful in inks and other pigments) are cyan, magenta, and yellow. This is what they ought to use in art classes.
The additive secondaries are the subtractive primaries, and vice versa; the two spectra are complementary. (As an additive primary is light of a frequency which stimulates only one of the cone types in the human eye, and a subtractive primary is something which absorbs only one such frequency range and reflects the rest).
Thus, the complement of red is not green, but cyan, which is a sort of blue-green. Interestingly enough, some of the earliest and most prevalent photosynthetic life forms were the blue-green algae, also known as cyanobacteria.
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
As a matter of fact I think Richard Dawkins is a complete prat, a leftover from the obsolete battles of the nineteenth century. I side with people like Jay Gould (RIP) and Robert Winston on all of this.
But I was writing about something special, the situation in the US where you have very backward, scientifically illiterate Protestant fundamentalists (who never seem to be able to read the Bible in the original, strangely) who have considerable power in Government and the media, and so scientists see themselves as being in conflict with them. Most US scientists do not work in institutions where they come into contact with modern religious thinkers, whereas they do watch television.
While on this somewhat off-topic explication, I'd like to add that I'm a fan of the Episcopalian Church, which to my mind is where the US ought to be. It's a tragedy that the Church of England is siding with the bonkers African bishops against the Episcopalians, instead of telling them to behave like civilised people or stop calling themselves Anglicans.
I'm sure I don't know as much about the history and sociology of religion as I ought to, but I don't think anything I have written would actually support the idea that I'm opposed to modern liberal Christianity.
As for my remarking on the view that fundamentalists can switch from one fundamentalism to another, this is a well known piece of religious sociology. Leaving Godwin and his law completely out of his, how about the studies that showed that in France and Italy post-WW2, Catholics moving to Communist areas frequently became Communists? There are various explanations that can be put forward, but one simple one is that people who become fundamentalists, or communists, or fascists, are people who are prone to accept the views put forward by authority figures rather than rebel against them. This isn't derogatory.
Pining for the fjords
late 19th oil wells in the US that were abandoned after being pumped by have magically refilled themselves, I might take the "abiotic" crap seriously. At this point, it has to be put into the junk science category along with the garbage ExxonMobil expects us to take seriously about global warming being "imaginary".
Tech Public Policy stuff
One learns in thermal physics that the suns wavelength density peaks somewhere in the red wavelenghts of light, but this is of no importance to the plant because it cares more about the energy density of light when utilizing photosynthesis. The peak of energy density of sun light is not green either.
In your tag line you stated "605413? Yes, it's a prime."
Base 10 and base 16, yes, but not base 8, where 605143 = 5 * 115717.
Just being pedantic, as to be expected of a slashdot user.
--
I'm really a nice guy. If I had friends, they would tell you.
I'm glad you cleared that up!
/sarcasm
I can see now how it's all a big cover-up (just like the moon landing) and all the independent and peer-rewiewed answers have been predetermined since that monk with the pea plants forged his results. It was just one monk who started all this but generations of scientists have conspired to ignore the methods handed from God to Newton in favour of "piltdown-science", these modern day monks make a concerted and largely sucessfull effort to hide the "truth" that is known only to "God's messengers", the creationists.
The evil misinformation about pea plants and hominoids that pours from the monks of modern science is the contents of pandoras box, we can't close the lid but surely we can dispose of the box. It's high time we gave authority over natures laws back to the church, the inquisition got rid of witches and they can get rid of those heretics who won't conform to the alice-in-wonderland world view of gods chosen people. And I don't mean "wonderland" in a derogatory sense, who are they to judge God's plan for humans and dinosours as revealed by the creationist's "truth", it is plain the creationists are right the references they quote are right there in the bible for all motel patrons to see and in their museam they physicaly demonstarte that dinosurs could indeed wear a saddle.
BTW: Now that I am converted, where are my slaves, don't give me that namby-pamby UN BS about human rights, the bible says I can have slaves, dammit I need my slaves to look after all the kids god is going to bless me with, and don't forget my conqubines - I imagine rotating the same 6 wives will rapidly become as sexually boring as monogomy.
BTW: This post required a rather large hit of angel dust to work up the right level of parinioa and religous ferver to do it justice and several bongs to calm down afterwards. I am not hostile towards personal faith, my partner is religious and just last year I was lucky enough to sit in on a public service at Westminster abbey with her. But please, show me and others educated in science the same kind of respect and "christian charity". Learn something about what you are critisizing and critisize the "science" you are preaching, none of this means you have to "question your faith" but it may result in you dumping organised religion.
Start with the skill of skeptcisim (AKA "critical thinking"), "Doubting Thomas", JREF and Sagan are good guides from different view points. Learning the skill takes a lifetime but the basics are not hard, find out why "peer-review" is so important, look up the meaning of "the republic of science" and "the scientific method", while you are there find out what the difference is between "opinion/fact", "anecdote/observastion", "idea/debunked idea", "theory/dogma", "testable/tested", "logic/rhetoric", "statistics/individual outcome", "science" and "established science". If you are connected to the net there is very little excuse for the unfortuately common ignorance about the philosphy and methods of modern science and the awe inspiring miricales it reveals for all to see.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.