Posted on 11/04/2005 5:00:06 AM PST by PatrickHenry
Minerals help molecules thought to have been essential for early life to form.
A team of US scientists may have found the 'primordial womb' in which the first life on Earth was incubated.
Lynda Williams and colleagues at Arizona State University in Tempe have discovered that certain types of clay mineral convert simple carbon-based molecules to complex ones in conditions mimicking those of hot, wet hydrothermal vents (mini-volcanoes on the sea bed). Such complex molecules would have been essential components of the first cell-like systems on Earth.
Having helped such delicate molecules to form, the clays can also protect them from getting broken down in the piping hot water issuing from the vents, the researchers report in the journal Geology [Williams L. B., et al. Geology, 33. 913 - 916 (2005).].
"It's very interesting that the clays preserve them," says James Ferris, a specialist on the chemical origins of life at Rensselaer Polytechnic Institute in Troy, New York. "It shows that this could be an environment where complex organic molecules can be formed."
Some like it hot
Hydrothermal vents are created when seawater that has seeped through cracks in the seafloor is heated by magma just below the surface. The water streams back out of the rock in a plume that can reach temperatures of around 400 °C.
Vents are a favourite candidate for the site where life first appeared. Their heat provides an energy source; the minerals provide nutrients; and the deep-sea setting would have protected primitive organisms from the destructive meteorite impacts that scoured the planet's surface early in its history.
But researchers have long wondered how, if early life did form in this environment, it escaped being boiled and fried by the harsh conditions.
The Arizona State team has shown that clay minerals commonly found at vents can encase organic molecules, keeping them intact.
Between the sheets
The group simulated the vent environment in the laboratory, immersing various types of clay in pressurized water at 300 °C for several weeks and looking at the fate of a simple organic compound, methanol, in this stew. They chose methanol because their earlier work had shown that the compound could be formed in a vent environment from simple gases such as carbon dioxide and hydrogen.
Clays generally consist of sheets made of aluminium, silicon and oxygen atoms, which are stacked on top of one another. In some of these materials, such as the clays saponite and montmorillonite, there is room for other atoms and molecules to slip between the layers.
Spouting soup
The researchers found that the methanol in their artificial vent system was converted to various large organic molecules over six weeks or so, so long as the clay's layers were spaced widely enough to hold the compounds.
"The clay provides a safe haven for the organic molecules, essentially like a 'primordial womb'," the team reports. Eventually, changes in the clay's mineral structure caused by heat, pressure and time may cause the sheets to close up and expel the molecules inside. But they think that some of these could spout out from the clay into less hostile environments than the hottest part of the vent, creating an organic soup in which life might arise.
These findings add weight to the idea that clays were the key to the origin of life. Previous research has shown that clays act as catalysts for the formation of polymer molecules such as the precursors of proteins and DNA. They can also encourage lipid molecules to arrange themselves into cell-like compartments called vesicles.
But this is a really big number isn't it?
I think AARP starts sending you junk mail when you hit 45. Then you notice that everything you like on TV seems to have sponsors that are selling laxatives, denture adhesives, and remedies for what Bob Dole calls "ED." It's all downhill from there.
G3k sure seemed to think so for about three days....
Did anybody catch Peter Ward on radio last night? He says they are going to look for earth fossils on the moon. Series.
How about a good "You kids get off my lawn!"
You do need to think about these things before writing.
Current thinking???
You mean they thought something else before??
Maybe THEY should think before publishing.
Too much might make ya nuts....
Acts 26:24-25
24 At this point Festus interrupted Paul's defense. "You are out of your mind, Paul!" he shouted. "Your great learning is driving you insane." 25 "I am not insane, most excellent Festus," Paul replied. "What I am saying is true and reasonable.
I thought Cialis is supposed to fix that.
If selection of fitness translates to reproduction as a goal of natural selection, then how do you explain homosexuality, which necessarily yields a state of reproductive stasis. Furthermore, why could I not then conclude that your claim is incorrect, since such a goal of reproductive stasis is the observation which would falsify your claim. And lastly, if such an observation of reproductive stasis does not falsify your claim, then how can the claim be useful, let alone falsifiable, if it can accommodate states which are in opposition to each other.
You're not alone. Others have trouble with his stuff, too.
2 Peter 3:15-16
15Bear in mind that our Lord's patience means salvation, just as our dear brother Paul also wrote you with the wisdom that God gave him. He writes the same way in all his letters, speaking in them of these matters. His letters contain some things that are hard to understand, which ignorant and unstable people distort, as they do the other Scriptures, to their own destruction.
Define 'primitive'.
Wouldn't a fossil of the Earth be quite a bit larger than the entire moon? How would they dig it up? How would they document its location?
So does Elmer Fudd...
Had that one down long ago. I'm now working on 'Give you $5.00 to shovel my walk'.
Well, there is a theory that the Moon was blasted from the Earth by a big chunk of impacting something...
"Everyone be nice."
Akin to handing an arsonist a can of gas knowing he brought his own matches to the party.
Also heard Peter Ward learn that the sun is 100 times earth's diameter. Who knew that he didn't know?
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