Evolution? How?

Now before this thing formed, what did we have? A self replicating molecule alone which has just formed.

And moments later, it is surrounded by a protective membrane. How do we suppose this happened?

The first survival-of-the-fittest competition was likely a physical duel between fatty bubbles stuffed with genetic material, researchers from the Howard Hughes Medical Institute are proposing.

The researchers, led by Howard Hughes.......

Perhaps the notion of Martian seeding as I made reference to earlier will assert itself.

As far the origins of life on earth (exempting the premise of proto-life / self-replicating molecules etc.) it's vastly more plausible that it was from seeding than from any religious belief.

Which begs the question: if a religionist is arguing the origin of life from a plausibility context, then seeding (intentional or accidental) holds way more merit than any religious belief in the origins of life.

What came first the chicken or the egg?

The Bible says that God formed man from the dust of the ground... Then God breathed into his nostrils the breath of life...

The body is the empty shell and the soul is the life that animates.

So was the DNA breathed into the mitocondria?

Skepticism Greets Claim Of Possible Alien Microbes Special to World Science
1-8-6

A paper to appear in a scientific journal claims a strange red rain might have dumped microbes from space onto Earth four years ago. But the report is meeting with a shower of skepticism from scientists who say extraordinary claims require extraordinary proof-and this one hasn't got it.

The scientists agree on two points, though. The things look like cells, at least superficially. And no one is sure what they are.

"These particles have much similarity with biological cells though they are devoid of DNA," wrote Godfrey Louis and A. Santhosh Kumar of Mahatma Gandhi University in Kottayam, India, in the controversial paper.

"Are these cell-like particles a kind of alternate life from space?"

The mystery began when the scarlet showers containing the red specks hit parts of India in 2001. Researchers said the particles might be dust or a fungus, but it remained unclear.

The new paper includes a chemical analysis of the particles, a description of their appearance under microscopes and a survey of where they fell. It assesses various explanations for them and concludes that the specks, which vaguely resemble red blood cells, might have come from a meteor.

A peer-reviewed research journal, Astrophysics and Space Science, has agreed to publish the paper. The journal sometimes publishes unconventional findings, but rarely if ever ventures into generally acknowledged fringe science such as claims of extraterrestrial visitors.

If the particles do represent alien life forms, said Louis and Kumar, this would fit with a longstanding theory called panspermia, which holds that life forms could travel around the universe inside comets and meteors.

These rocky objects would thus "act as vehicles for spreading life in the universe," they added. They posted the paper online this week on a database where astronomers often post research papers.

Louis and Kumar have previously posted other, unpublished papers saying the particles can grow if placed in extreme heat, and reproduce. But the Astrophysics and Space Science paper doesn't include these claims. It mostly limits itself to arguing for the particles' meteoric origin, citing newspaper reports that a meteor broke up in the atmosphere hours before the red rain.

John Dyson, managing editor of Astrophysics and Space Science, confirmed it has accepted the paper. But he said he hasn't read it because his co-managing editor, the European Space Agency's Willem Wamsteker, handled it. Wamsteker died several weeks ago at age 63.

A paper's publication in a peer-reviewed journal is generally thought to give it some stamp of scientific seriousness, because scientists vet the findings in the process. Nonetheless, the red rain paper provoked disbelief.

"I really, really don't think they are from a meteor!" wrote Harvard University biologist Jack Szostak of the particles, in an email. And this isn't the first report of red rain of biological origin, Szostak wrote, though it seems to be the most detailed.

Szostak said the chemical tests the researchers employed aren't very sensitive. The so-called cells are admittedly "weird," he added, saying he would ask his microbiologist friends what they think they are.

"I don't have an obvious explanation," agreed prominent origins-of-life researcher David Deamer of the University of California Santa Cruz, in an email. They "look like real cells, but with a very thick cell wall. But the leap to an extraterrestrial form of life delivered to Earth must surely be the least likely hypothesis."

A range of additional tests is needed, he added. Louis agreed: "There remains much to be studied," he wrote in an email.

The researchers didn't dispute the panspermia theory itself, which has a substantial scientific following. "Panspermia may well be possible," wrote Lynn J. Rothschild of the NASA Ames Research Center in Moffett Field, Calif., in an email. "I'm just not so sure that this is a case of it."

Others viewed the study more favorably.

"I think more careful examination of the red rain material is needed, but so far there seems to be a strong prima facie [first-glance] case to suggest that this may be correct," said Chandra Wickramasinghe, director of the Cardiff Centre for Astrobiology at Cardiff University, U.K., and a leading advocate of panspermia.

The story of the specks began on July 25, 2001, when residents of Kerala, a state in southwestern India, started seeing scarlet rain in some areas.

"Almost the entire state, except for two northern districts, have reported these unusual rains over the past week," the BBC online reported on July 30. "Experts said the most likely reason was the presence of dust in the atmosphere which colours the water."

The explanation didn't satisfy everyone.

The rain "is eluding explanations as the days go by," the newspaper Indian Express reported online a week later. The article said the Centre for Earth Science Studies, based in Thiruvananthapuram, India, had discarded an initial hypothesis that a streaking meteor triggered the rain, in favor of the view that the particles were spores from a fungus.

But "the exact species is yet to be identified. [And] how such a large quantity of spores could appear over a small region is as yet unknown," the paper quoted center director M. Baba as saying. Baba didn't return an email from World Science this week.

The red rain continued to appear sporadically for about two months, though most of it fell in the first 10 days, Louis and Kumar wrote. The "striking red colouration" turned out to come from microscopic, mixed-in red particles, they added, which had "no similarity with usual desert dust."

At least 50,000 kg (55 tons) of the particles have fallen in all, they estimated. "An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like dust storms etc. cannot explain" it.

"The red particles were uniformly dispersed in the rainwater," they wrote. "When the red rainwater was collected and kept for several hours in a vessel, the suspended particles have a tendency to settle to the bottom."

"The red rain occurred in many places during a continuing normal rain," the paper continued. "It was reported from a few places that people on the streets found their cloths stained by red raindrops. In a few places the concentration of particles were so great that the rainwater appeared almost like blood."

The precipitation, the researchers added, had a "highly localized appearance. It usually occur[ed] over an area of less than a square kilometer to a few square kilometers. Many times it had a sharp boundary, which means while it was raining strongly red at a place a few meters away there were no red rain." A typical red rain lasted from a few minutes to less than about 20 minutes, they added.

The scientists compiled charts of where and when the showers occurred based on local newspaper reports.

The particles look like one-celled organisms and are about 4 to 10 thousandths of a millimeter wide, the researchers wrote, somewhat larger than typical bacteria.

"Under low magnification the particles look like smooth, red coloured glass beads. Under high magnifications (1000x) their differences in size and shape can be seen," they wrote.

"Shapes vary from spherical to ellipsoid and slightly elongated These cell-like particles have a thick and coloured cell envelope, which can be well identified under the microscope." A few had broken cell envelopes, they added.

The particles seem to lack a nucleus, the core DNA-containing compartment that animal and plant cells have, the researchers wrote. Chemical tests indicated they also lacked DNA, the gene-carrying molecule that most types of cells contain.

Nonetheless, Louis and Kumar wrote that the particles show "fine-structured membranes" under magnification, like normal cells.

The outer envelope seems to contain an "inner capsule," they added, which in some places "appears to be detached from the outer wall to form an empty region inside the cell. Further, there appears to be a faintly visible mucus layer present on the outer side of the cell."

"One characteristic feature is the inward depression of the spherical surface to form cup like structures giving a squeezed appearance," which varies among particles, they added.

"The major constituents of the red particles are carbon and oxygen," they wrote. Carbon is the key component of life on Earth. "Silicon is most prominent among the minor constituents" of the particles, Louis and Kumar added; other elements found were iron, sodium, aluminum and chlorine.

"The red rain started in the State during a period of normal rain, which indicate that the red particles are not something which accumulated in the atmosphere during a dry period and washed down on a first rain," the pair wrote.

"Vessels kept in open space also collected red rain. Thus it is not something that is washed out from rooftops or tree leaves. Considering the huge quantity of red particles fallen over a wide geographic area, it is impossible to imagine that these are some pollen or fungal spores which have originated from trees," they added.

"The nature of the red particles rules out the possibility that these are dust particles from a distant desert source," they wrote, and such particles "are not found in Kerala or nearby place."

One easy assumption is that they "got airlifted from a distant source on Earth by some wind system," they added, but this leaves several puzzles.

"One characteristic of each red rain case is its highly localized appearance. If particles originate from distant desert source then why [was] there were no mixing and thinning out of the particle collection during transport"? they wrote.

"It is possible to explain this by assuming the meteoric origin of the red particles. The red rain phenomenon first started in Kerala after a meteor airburst event, which occurred on 25th July 2001 near Changanacherry in [the] Kottayam district. This meteor airburst is evidenced by the sonic boom experienced by several people during early morning of that day.

"The first case of red rain occurred in this area few hours after the airburst... This points to a possible link between the meteor and red rain. If particle clouds are created in the atmosphere by the fragmentation and disintegration of a special kind of fragile cometary meteor that presumably contain[s] a dense collection of red particles, then clouds of such particles can mix with the rain clouds to cause red rain," they wrote.

The pair proposed that while approaching Earth at low angle, the meteor traveled southeast above Kerala with a final airburst above the Kottayam district. "During its travel in the atmosphere it must have released several small fragments, which caused the deposition of cell clusters in the atmosphere."

Alive or dead, the particles have some staying power, if the paper is correct. "Even after storage in the original rainwater at room temperature without any preservative for about four years, no decay or discolouration of the particles could be found."

Farmerman,

While you were gone, the ID controversy has hit England in a big way (national science education standards).

ID THREAD

real life wrote:

Now before this thing formed, what did we have? A self replicating molecule alone which has just formed.

And moments later, it is surrounded by a protective membrane. How do we suppose this happened?

Don't worry. Scientists are working their little fingers to the bone trying to answer your questions.

http://www.hhmi.org/news/szostak4.html
September 03, 2004
Battle of the Bubbles May Have Sparked Evolution
The first survival-of-the-fittest competition was likely a physical duel between fatty bubbles stuffed with genetic material, researchers from the Howard Hughes Medical Institute are proposing. The scientists suggest that genetic material that replicated quickly may have been all the bubbles needed to edge out their competitors and begin evolving into more sophisticated cells.
This possibility, revealed by laboratory experiments with artificial fatty acid sacs, contrasts sharply with a current theory of the earliest evolution of cells, which suggests that cellular evolution was driven by primordial genetic machinery that actively synthesized cell membranes or otherwise influenced cell stability or division.


The researchers, led by Howard Hughes Medical Institute investigator Jack W. Szostak, published their findings in the September 3, 2004, issue of the journal Science. Szostak and first author Irene Chen, both from Massachusetts General Hospital and Harvard Medical School, collaborated on the studies with Richard Roberts of the California Institute of Technology.
Cells are basically sacs encapsulated by bilayered membranes of fatty acids and other lipids, plus proteins. A central question in evolution is how simple versions of these cells, or vesicles, first arose and began the competitive process that drove the evolution of life.
"Most of the previous thinking about how cells grew and evolved was based on the idea of the initial evolution of structural RNAs or ribozymes ?- enzymes that could synthesize membrane molecules," said Szostak. The ribozymes might have made more membrane material while the structural RNAs might have formed a cytoskeleton that influenced stability, shape, growth or division, he said.
However, Szostak and his colleagues theorized that a far simpler physical process might explain why cells would compete with one another for the materials necessary to expand their size.
"We proposed that the genetic material could drive the growth of cells just by virtue of being there," he said. "As the RNA exerts an osmotic pressure on the inside of these little membrane vesicles, this internal pressure puts a tension on the membrane, which tries to expand. We proposed that it could do so through the spontaneous transfer of material from other vesicles nearby that have less internal pressure because they have less genetic material inside."
In order to test their theory, the researchers first constructed simple model "protocells," in which they filled fatty-acid vesicles with either a sucrose solution or the same solvent without sucrose. The sucrose solution created a greater osmotic pressure inside the vesicles than the solvent alone. The membranes of the simple vesicles were not as sophisticated as the membranes of today's living cells, said Szostak. However, they closely resembled the kinds of primordial vesicles that might have existed at the beginning of evolution.
When the scientists mixed the two vesicles, they observed that the ones with sucrose - in which there was greater membrane tension - did, indeed, grow by drawing membrane material from those without sucrose.
"Once we had some understanding that this process worked, we moved on to more interesting versions, in which we loaded the vesicles with genetic molecules," said Szostak. The researchers conducted the same competition tests using vesicles loaded with the basic molecular building blocks of genetic material, called nucleotides. Next, they used RNA segments, and finally a large, natural RNA molecule. In all cases, they saw that the vesicles swollen with genetic material grew, while those with no genetic material shrank.
It is important to note, said Szostak, the concentrations of genetic material that his group used were comparable to those found in living cells.
"In contrast to the earlier idea that Darwinian competition at the cellular level had to wait until the evolution of lipid-synthesizing ribozymes or structural RNAs, our results show that all you would need is to have the RNA replicating," said Szostak. "The cells that had RNA that replicated better ?- and ended up with more RNA inside ?- would grow faster. So, there is a direct coupling between how well the RNA replicates and how quickly the cell can grow. It's just based on a physical principle and would emerge spontaneously," he said.
According to Szostak, the next step in the research will depend on another major effort under way in his laboratory to create artificial, replicating RNA molecules.
"If we can get self-replicating RNAs, then we can put them into these simple membrane compartments and hope to actually see this competitive process of growth that we are hypothesizing," he said.

to read more on Szostak's work
http://genetics.mgh.harvard.edu/szostakweb/publications/publications.html
http://www.hhmi.org/research/investigators/szostak.html

Hi Pauligirl,

That's pretty handy if the first little protocells had a beneficient scientist nearby to put xNA molecules inside the membrane. But how did they do it on their own?

If the membrane formed independently of the xNA molecule and then surrounded it, then when it comes time to reproduce there is no code in the xNA molecule to give it's offspring a membrane.

If, almost immediately after it formed itself, the xNA molecule generated the membrane then where did the information to do so come from?