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.
I swear they coordinate this stuff or crib off each other or something.
It's all downhill from there.
Thanks for the heads ups.
You're far from farthood, maybe just a Little Toot.
I rather like phrases like "during the middle of the last century" or "this has a fin de siècle air about it" or the like.
I am usually just a lurker on these threads, and am glad to see your tagline, as it does distinguish you from that other poster on the CREVO threads...I actually was able to keep the two of you separate in my mind, but your tagline just makes it much easier...
Indeed, look how wound up somebody gets!
I will repeat it again, you lying piece of garbage.
Oh, wait! That's g3k talking to dbeebs in your first link.
Fitness applies to species (or other groupings), not individuals. Ants and bees seem to do quite well with over 99% of the individuals being sterile. Individual homosexuals may not have their genes passed on but that has no more bearing on human evolution than the failure of many heterosexuals to bear children.
Non-breeders may be useful.
or....
1) they are the same person, or
2) they share a common source.
Note that Howard Phillips used the same phrase in an article....
Is it true that you can tell the upper class neighborhoods in Canada by their indoor Curling Rinks.... the lower classes have to contend with the proverbial outdoor rink in th back yard!
That's not what my wife says.
Yeah; but just wait until the NEXT time you need a tagline; BIG BUCKS!
The century mark really has a big impact on perceived age. My grandson gives me that 'holy cow you're old' look when I mention things I did the previous century. Anything that happened in the 20th is ancient history to him. Every time I hear 'at the end of the last century' I automatically pop back to the 19th. I may never get used to this being alive in the 21st century.[sigh]
In another 10 years it will seem quite natural. By then, they'll be labeling things as the "crime of the century!" the way they did with Leopold & Loeb back ... when was it ... the 1920s?
No longer. There is an indoor curling rink on every second corner. The back yard rinks are for hockey. Too many people want to play hockey on too few indoor hockey rinks.
Taglines-R-US; one-stop tagline shopping to distinguish yourself from the Trolls & riff-raff.
Capitilist.
Peter of course castigates "ignorant" people. That is those people who refuse to listen to proper teaching authority.
Nothing like making claims when only the first 20% of the century has gone by. Journalists [disgusted look on my face]. If the news is boring, spin it as fast as possible.
Infrequent bathing and tendency to sex with camels.
The French in Morocco?
Sorry, I really didn't mean that. The set up was just too perfect. Now I'm sure some creo will use that as proof of my bigotry.
Oh well, I've already been called a Nazi and a Communist.
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