Stanley Miller's classic "primordial soup" experimental setup,
with a simulated ocean, lightning and broth
of hydrogen, methane, ammonia and water.
Posted on 04/08/2005 7:39:14 AM PDT by PatrickHenry
A new University of Colorado at Boulder study indicates Earth in its infancy probably had substantial quantities of hydrogen in its atmosphere, a surprising finding that may alter the way many scientists think about how life began on the planet.
Published in the April 7 issue of Science Express, the online edition of Science Magazine, the study concludes traditional models estimating hydrogen escape from Earth's atmosphere several billions of years ago are flawed. The new study indicates up to 40 percent of the early atmosphere was hydrogen, implying a more favorable climate for the production of pre-biotic organic compounds like amino acids, and ultimately, life.
The paper was authored by doctoral student Feng Tian, Professor Owen Toon and Research Associate Alexander Pavlov of CU-Boulder's Laboratory for Atmospheric and Space Physics with Hans De Sterk of the University of Waterloo. The study was supported by the NASA Institute of Astrobiology and NASA's Exobiology Program.
"I didn't expect this result when we began the study," said Tian, a doctoral student in CU-Boulder's Astrobiology Center at LASP and chief author of the paper. "If Earth's atmosphere was hydrogen-rich as we have shown, organic compounds could easily have been produced."
Scientists believe Earth was formed about 4.6 billion years ago, and geologic evidence indicates life may have begun on Earth roughly a billion years later.
"This study indicates that the carbon dioxide-rich, hydrogen-poor Mars and Venus-like model of Earth's early atmosphere that scientists have been working with for the last 25 years is incorrect," said Toon. In such atmospheres, organic molecules are not produced by photochemical reactions or electrical discharges.
Toon said the premise that early Earth had a CO2-dominated atmosphere long after its formation has caused many scientists to look for clues to the origin of life in hydrothermal vents in the sea, fresh-water hot springs or those delivered to Earth from space via meteorites or dust.
The team concluded that even if the atmospheric CO2 concentrations were large, the hydrogen concentrations would have been larger. "In that case, the production of organic compounds with the help of electrical discharge or photochemical reactions may have been efficient," said Toon.
Amino acids that likely formed from organic materials in the hydrogen-rich environment may have accumulated in the oceans or in bays, lakes and swamps, enhancing potential birthplaces for life, the team reported.
The new study indicates the escape of hydrogen from Earth's early atmosphere was probably two orders of magnitude slower than scientists previously believed, said Tian. The lower escape rate is based in part on the new estimates for past temperatures in the highest reaches of Earth's atmosphere some 5,000 miles in altitude where it meets the space environment.
While previous calculations assumed Earth's temperature at the top of the atmosphere to be well over 1,500 degrees F several billion years ago, the new mathematical models show temperatures would have been twice as cool back then. The new calculations involve supersonic flows of gas escaping from Earth's upper atmosphere as a planetary wind, according to the study.
"There seems to have been a blind assumption for years that atmospheric hydrogen was escaping from Earth three or four billion years ago as efficiently as it is today," said Pavlov. "We show the escape was limited considerably back then by low temperatures in the upper atmosphere and the supply of energy from the sun."
Despite somewhat higher ultraviolet radiation levels from the sun in Earth's infancy, the escape rate of hydrogen would have remained low, Tian said. The escaping hydrogen would have been balanced by hydrogen being vented by Earth's volcanoes several billion years ago, making it a major component of the atmosphere.
In 1953, University of Chicago graduate student Stanley Miller sent an electrical current through a chamber containing methane, ammonia, hydrogen and water, yielding amino acids, considered to be the building blocks of life. "I think this study makes the experiments by Miller and others relevant again," Toon said. "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept."
In the new CU-Boulder scenario, it is a hydrogen and CO2-dominated atmosphere that leads to the production of organic molecules, not the methane and ammonia atmosphere used in Miller's experiment, Toon said.
Tian and other team members said the research effort will continue. The duration of the hydrogen-rich atmosphere on early Earth still is unknown, they said.
I must have missed these two: could you post the Scripture references?
Selection is a CHOICE; a decision between two or more criteria that involves study of certain qualities of the items being selected.
Qualities ARE information; therefore the mere selection CANNOT be 'the' source of 'information'.
I, and I think most of those on the pro-evolution side, have absolutely no problem with those who believe in either creationism or ID as a matter of faith. In fact, one of my main points in all of these threads is that a belief in God is not in any way incompatible with any modern scientific theory, evolution included. In fact, that is my personal position. The problem I have (and I believe the problem most other evolution supporters have) is with the creationists who instead of saying, "We see and understand the evidence you have for evolution, and will admit that evolution is a reasonable conclusion based on this evidence, but my faith tells me that it's wrong," but rather will try to use misstatements of what the theory of evolution says, mischaracterization of the evidence in favor of evolution, and outright lies about the scientific community in order to try to knock down evolution. As a scientist, I am perfectly willing to accept that evolution might very well be wrong, and that creationism or ID might very well be correct. However, science is not the way, at least for creationism, to find this out. Creationism is not falsifiable and never will be, since no conceivable observation is incompatible with an omnipotent God. ID is not now, but could potentially be falsifiable. What is needed is some conclusive test for the presence of design. Given that, it would be, at least theoretically, a trivial matter to settle the question of design in life. Without that, however, all we have is a philosophical/religious debate, not science.
As far as your assertion that organized complexity doesn't spontaneously arise from chaos, that's not necessarily true in all cases. Consider the chaos of molecules of water vapor in the cold upper layers of the troposphere. These cold, chaotic molecules will spontaneously give rise to a very ordered and symmetric arrangement of solid water molecules, namely a snowflake. Furthermore, arguments from improbability are not necessarily convincing. For example, I could use an argument from improbability to prove that you don't exist. After all, there are several million genes in your genome. Presumably if one of these is changed, the result would be a different person. Hence, since it's so extremely unlikely that all these millions of genes would arrange themselves in the manner needed to produce you, it's extremely unlikely that you exist. The real truth is that all kinds of extremely unlikely events are constantly occurring.
The difference between the idea that the universe has always existed and the idea of God WRT the ability to test them scientifically is that while we can't test either one now, in principle it is possible to test the idea that the universe has always existed, but it is impossible to test for the existence of God. The first would require new technology and/or more ingenious scientists. To test something, however, implies that the result of your test could in fact turn out negative. However, if your belief is in an omnipotent God, then there's no possible observation that could cause you to reject that idea. God could cause you to see anything He wants you to see. Therefore, a meaningful test of God's existence is not possible even in principle.
You know that the Krebs cycle doesn't exist in anaerobic bacteria, which are some of the simplest currently existing organisms. The Krebs cycle only operates in aerobic organisms. Anaerobic organisms derive energy exclusively from glycolysis.
Luk 6:29 And unto him that smiteth thee on the [one] cheek offer also the other; and him that taketh away thy cloke forbid not [to take thy] coat also.
Luk 6:30 Give to every man that asketh of thee; and of him that taketh away thy goods ask [them] not again.
Luk 18:22 Now when Jesus heard these things, he said unto him, Yet lackest thou one thing: sell all that thou hast, and distribute unto the poor, and thou shalt have treasure in heaven: and come, follow me.
Luk 18:25 For it is easier for a camel to go through a needle's eye, than for a rich man to enter into the kingdom of God.
Matt 5:39 But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also.
Matt 5:40 And if any man will sue thee at the law, and take away thy coat, let him have [thy] cloak also.
Matt 5:41 And whosoever shall compel thee to go a mile, go with him twain.
This statement clearly shows you either do not participate in or are unaware of the scientific process. A scientific hypothesis is used to construct and design an experiment. With respect to previous observations, this is an iterative process. Based upon current observations, i.e. Titan's environment is rich in hydrocarbons, my speculation is academically reasonable and is supoorted by the fact that hydrocarbon mixtures can and do contain a wide variety of chemical species.
I'm inclined to doubt your credentials, considering the above ridiculous statement. A scientist starts with an observation that needs an explanation. He doesn't start with a random fantasy.
Doubt all you want. It again shows you have a myoptic view of science and how it is performed, or it may be related to your area of secialization. This so called "flight of fantasy" is very close to what I work with day in and day out. And to a chemist, it is not unreasonable to believe that there will be a complicated brew of chemicals in such an environment, especially when you look at the low concentration ranges. Burn toast and you make thousands of different species, some of which are very nasty, but they are at such a low concentration, they can't harm you.
Let me clarify a bit here. Naturally, one would expect and receive a result, but the specific qualitative and quantitative nature of that result would be unexpected. It would be like having a newpaper subscription. You know the paper will likely be there in the morning and it will have headlines, but you don't know what those headlines are until you look at the paper.
It was and remains a flight of fancy. You yourself limited the species available by discussing it thereby limiting the available universe of possibilities to your speculation which remained unsupported by evidence.
Like I posted to mathemagician above, it is not a flight of fantasy (i.e. the Titan discussion). When you have a complicated mixture of hydrocarbons, you can and do get a wide variety of chemical species. At extremely low concentrations, the variety is huge. Anyone knowledgeable in analytical organic chemistry would be aware of this.
When delving into the unknown for the fisrt time, it is possible to know the constraints on an observation before knowing the specific observation. This is based entirely upon our knowledge of how things operate. For example, you may synthesize a new chemical in the lab and you will be able to predict the range of it's properties before it is synthesized based upon the nature of the chemistry involved, even though such a chemical may never have been observed in nature.
Finally, Since we know the world was without life and life arose from abiogenesis
I do not accept the sought after conclusion of a proof as an axiom in the said proof.
It is a fact that at one time the Earth was without life and at a later had life. We started with a world and life, through natural processes, came into existence. I suspect the part you do not like is the 'through natural processes.' That is the only scientific explaination. All processes are natural. Anything invoking creation or other such supernatural intervention, is outside the realm of science. No supernatural process has ever been documented as such.
I do not accept the sought after conclusion of a proof as an axiom in the said proof.
Nor does anyone else who has been introduced to even the slightest amount of logic.
Doc30, have you redefined what it means to know? If you have, then we all instantly know personal things about you which you have not told us.
Your patronizing reply is no evidence that your flight of fancy was not a speculation unsupported by evidence. I am familiar with "goo". In trying to "close"(form) a propane ring of a certain combination the result was always a "goo". It never developed legs and walked away. And the products, though "complex" were not of unlimited variety.
That is not what I wrote and you know it. And you also limit yourself to what you consider science. Without rational speculation, science has no starting point. I stres the term rational, but you refuse to see the logical progression that lead to that rationalization. What I did write is testable and you know it. Based on previous chemical knowledge, this hypothesis is valid and can be confirmed or refuted by testing. If you get a chance to actually work in science, which I can tell you have not, you will understand this.
How hard is it to understand that the world, in the distant past was lifeless. There is no evidence of life past a certain point in time. After a certain point in time, there is evidence of life. Buth then again, people who back a creationsist mindset do not like facts to get in the way.
And you don't understand logic. Below the ruins of "X" there is no evidence of habitation. Your logical conclusion is that "X" arose from rocks by itself.
Perhaps this is another proof of the Intelligent Designer.
I always imagined it not as primordial soup, but as more of a primordial open-faced sandwich.
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