Posted on 06/14/2008 12:22:54 AM PDT by LibWhacker
PARIS (AFP) - Genetic material from outer space found in a meteorite in Australia may well have played a key role in the origin of life on Earth, according to a study to be published Sunday.
European and US scientists have proved for the first time that two bits of genetic coding, called nucleobases, contained in the meteor fragment, are truly extraterrestrial.
Previous studies had suggested that the space rocks, which hit Earth some 40 years ago, might have been contaminated upon impact.
Both of the molecules identified, uracil and xanthine, "are present in our DNA and RNA," said lead author Zita Martins, a researcher at Imperial College London.
RNA, or ribonucleic acid, is another key part of the genetic coding that makes up our bodies.
These molecules would also have been essential to the still-mysterious alchemy that somehow gave rise, some four billion years ago, to life itself.
"We know that meteorites very similar to the Murchison meteorite, which is the one we analysed, were delivering the building blocks of life to Earth 3.8 to 4.5 billion years ago," Martins told AFP in an interview.
Competing theories suggest that nucleobases were synthesised closer to home, but Martins counters that the atmospheric conditions of early Earth would have rendered that process difficult or impossible.
A team of European and US scientists showed that the two types of molecules in the Australian meteorite contained a heavy form of carbon -- carbon 13 -- which could only have been formed in space.
"We believe early life may have adopted nucleobases from meteoric fragments for use in genetic coding, enabling them to pass on their successful features to subsequent generations," Martins said.
If so, this would have been the start of an evolutionary process leading over billions of years to all the flora and fauna -- including human beings -- in existence today.
The study, published in Earth Planetary Science Letters, also has implications for life on other planets.
"Because meteorities represent leftover materials from the formation of the solar system, the key components of life -- including nucleobases -- could be widespread in the cosmos," said co-author Mark Sephton, also at Imperial College London.
"As more and more of life's raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely," he said.
Uracil is an organic compound found in RNA, where it binds in a genetic base pair with another molecule, adenine.
Xanthine is not directly part of RNA or DNA, but participates in a series of chemical reactions inside the RNA of cells.
The two types of nucleobases and the ratio of light-to-heavy carbon molecules were identified through gas chromatography and mass spectrometry, technologies that were not available during earlier analyses of the now-famous meteorite.
Even so, said Martins, the process was extremely laborious and time-consuming, one reason it had not be carried out up to now by other scientists.
My grandfther was a 33rd degree Mason. My connection is more tenuous in that I have his books and a Mason Jar.
That may explain my prediliction to study botany and strong Darwinist beliefs. For all these years I thought I was just a scientist, but Free Republic has taught me I am actually a Darwinist.
The rectangles appear to have PSI geometry....The Golden section in design is independant of Masonry
Hi, TigersEye! On Earth, yes, that’s enough to get us going.
Now I may have misunderstood the poster; I interpreted her comment to be a statement in support of intelligent design, given how unlikely life was to arise by chance.
But we just don’t know yet what those odds are and the number of planets out there supporting life is still a wide open question. Could be a few, could be trillions upon trillions. imo
Lord Luther is a myth construct, as is King Arthur, son of Uther Pendragon.
“Lord” is a redundancy, as the “L” in “Luther” is a corruption of El, meaning Lord.
“Luther” itself is a corruption of El-Uther.
This marks him as a Krypton related to the lords of the R-Turd clan, which is hereditarily opposed to Jor-El, whom we know is not just a Kryptonian, but a Kryptonian Science Lord...i.e. a 'wizard'.
Kal-El and El-X (an atificially genetically enhanced experimental model of Kryptonian) continue the ancient rivally on Earth, known to us as Clark (Kal-El) Kent and Lex (El-X Uthur) Luther.
I have 33 Mason jars, what does that make me?
No; C'Thulu/, after getting a shave & a haircut.
Grope Grope.
The ET’s and globalists will have a polished version of this to deceive the world with . . . complete with purported 3D ‘historical’ videos of ancient times . . .
wheee
stay tuned.
I don't care too much for Darwin. His credibility with me is about as high as the Clintons.
Who goes there?
However I meant that the 'miracle' of life arising from a fortunate coming together of materials and circumstances would only have to happen once in the entire universe. We don't know that it has happened anywhere else. Also, 'local' could be this galaxy. That would be a tiny enough speck in this universe to be remarkable yet the galaxy is big enough to make our solar system seem like a dust speck.
But if the 'chance' happening occurred early enough in the development of the universe life could have been seeded throughout it from just one occurrence. It is not just the molecules that make the building blocks of life that could be traveling all over space but living organisms themselves. They are being found in harsher and harsher environments here on earth all the time. How do we know, trapped on this fertile little ball (so far,) just how harsh of an environment a living organism can exist in or how long it could remain dormant yet viable?
Have you ever actually read the Origin of Species?
RNA/DNA is an information code. Information codes do not simply just sort of happen. No number of years, trillions, quadrillions, or anything else will help the problem. Competent mathematicians are on record to the effect that the debate should have ended on the day DNA and RNA were discovered. For that matter the laws of populatoin genetics indicate that even if macroevolutoin were possible which it isn’t, it would take quadrillions and quintillions of years to produce our present biosphere, and not billions or trillions.
Someone took the time to paint or draw that? That’s just weird.
Well, where does one begin, let’s see.
We live in the middle of space on a planet orbiting a star.
We are aliens.
Is this news?
I checked: and you’ve left out a ,000 in the second set.
Very observant. I noticed that too.
Even leaving that set out, the chances are still zero.
Oh, ok, I see what you're saying. Yes, I've heard that before myself and can see where it would be easy to believe that that might be true. But the universe is much, much too large for that to be the case.
Consider the vast voids they've recently discovered in the distribution of matter in the universe. Those voids are so vast that they and the distribution of matter around them must have been there from the moment of the Big Bang.
Cosomologists know that to be true because if there had ever been galaxies in those voids, there would still be galaxies in them... In other words, not enough time has elapsed since the Big Bang for galaxies to have vacated the voids, if galaxies had been there to begin with.
If galaxies haven't had time to move very far from their original (relative) positions, how could a single organism have propagated throughout the entire universe? It couldn't.
If the cosmos is teeming with life, it had to have evolved independently from scratch numerous times.
OTOH all of the same materials would have been evenly distributed throughout the universe and the same amount of time, more or less, would have existed in every galaxy for the immense game of craps to be played out in each. Now we are back to "just once is enough" for each galaxy or galaxy cluster.
Still some places might remain sterile to this day and others are veritable compost piles. If odds have anything to do with it.
But the odds equation depends on the idea that if particular molecules come together in particular circumstances life will form. What then are the odds that those molecules all came to exist independently as well as the environment needed to catalyze them into life once they all collected together?
It seemed logical, Captain. ;^)
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