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United States24747 Posts
In my current studies of astronomy, I've begun to tackle the issue of how life came to be on Earth. Of course, there is a lot of disagreement about how confident we can be in prevailing scientific theories. But, I didn't realize how ignorant I was on the scientist side of the argument.
Things I knew, more or less:
Much of the information we claim to know about what the Earth was like when life was most likely to begin is a combination of educated guesses and logical thoughts. Most signs of what the Earth was like so long ago were erased by violent surface activity (volcanoes, meteorites, etc). Still, we have concluded that the atmosphere was most likely composed of hydrogen, nitrogen, and carbon compounds (not so much free oxygen). Shortly after, ammonia, methane and carbon dioxide entered the mix.
I also was aware that natural sources of energy could have contributed towards the creation of live. Lightning (along with radioactivity, radiation, meteor impacts, and volcanoes) all helped to shape the naturally occurring elements and compounds into complex molecules suitable for creating life.
I thought the theory ended there.
What I now know more about:
The first step in creating life from inorganic compounds, according to the prevailing theory, is for amino acids and nucleotide bases to be created (these are organic, carbon based molecules). In the 1920s, this was first being addressed scientifically. It wasn't until 1953 that the Urey-Miller Experiment attempted to scientifically recreate the environment where life is believed to have first come about (primordial atmosphere).
The scientists created a chemical apparatus which stored a mixture of the gasses of the early Earth atmosphere (ammonia, methane, carbon dioxide, and water vapor). The gas was energized by a spark-discharge electrode to simulate lightning, the theorized catalyst for the necessary reactions. After a week of running the experiment, amino acids (including those found in most living organisms) and other complex molecules were found in a trap.
Since then, many other experiments have reproduced the same basic results, while varying many parts of the apparatus and conditions. Amazingly, it has been shown that organic molecules can be made from inorganic compounds simply with natural forces that most likely appeared on early Earth.
No organism has ever been made from one of these experiments, but I'm not surprised. If a few dozen scientists could be so successful in a short period of time, imagine what results could have occurred if given thousands or millions of years.
 
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i thought god created the earth in 7 days 5000 years ago
+ Show Spoiler +heh jk
the problem is, however, that nobody knows how those amino acids may have turned into a cell. They've tried for quite some time to smash the various chemicals together, such as in conditions similar to undersea trenches, but to no avail.
All I have to say is, that we sure are lucky that the first cell(s) didn't get pulverized by some random burst of lava or whatnot.
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United States24747 Posts
On August 20 2009 13:03 Caller wrote:i thought god created the earth in 7 days 5000 years ago + Show Spoiler +heh jk
the problem is, however, that nobody knows how those amino acids may have turned into a cell. They've tried for quite some time to smash the various chemicals together, such as in conditions similar to undersea trenches, but to no avail.
All I have to say is, that we sure are lucky that the first cell(s) didn't get pulverized by some random burst of lava or whatnot.
Maybe the first 100000 cells were all pulverized by lava. Who knows. Sooner or later, one made it through I guess hehe.
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This is going to start a huge debate of creation v.s. evolution.
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old
also they haven't been able to replicate amino acid -> polypeptide yet
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United States24747 Posts
On August 20 2009 13:26 SpiritoftheTunA wrote:
old
also they haven't been able to replicate amino acid -> polypeptide yet
Missing the point? I know it's old. The point is that I (and many others) were unaware that they had gotten as far with this as they had.
Yeah it's no surprise they haven't made it through all the steps to life yet. If so, I surely would have heard more about this.
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Russian Federation1381 Posts
Cool, didn't know there was any kind of progress. Anyway Earth then was such a horrible mess, we can't know every complicated detail and can only imagine what was going on billions years ago, we only have basic pieces of the puzzle i believe.
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learned this stuff in ap bio last year
actually we didnt learn it, i read it in the textbook
really cool
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On August 20 2009 13:03 Caller wrote:
i thought god created the earth in 7 days 5000 years ago
furthermore, he placed fossils and impact craters all over the place and in layers of the earth that correspond to eras in order to test our faith.
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I think that is abiogenesis, not evolution.
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On August 20 2009 14:11 CharlieMurphy wrote:Show nested quote +On August 20 2009 13:03 Caller wrote:
i thought god created the earth in 7 days 5000 years ago
furthermore, he placed fossils and impact craters all over the place and in layers of the earth that correspond to eras in order to test our faith.
LOL
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No need for debate with the whole "Intelligent Design" thing right? Plus, I really doubt there are many hardcore Christians on this forum who outright believe the bible is word for word literal truth.
But the idea of human's being able to create organisms would be quite interesting, and I didn't know we had created such early steps in the process (skipped out on Bio). Would love to see this sort of study progress further.
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I read in Dawkin's The Selfish Gene that it was possible for early ancestors (loosely used) of DNA (simple replicators) could have existed for the sole purpose of replicating, and when they began competing for resources, they started to "attack" each other, and many made protein armor out of the amino acids. Sounds possible and very interesting to me :O
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On August 20 2009 14:11 CharlieMurphy wrote:Show nested quote +On August 20 2009 13:03 Caller wrote:
i thought god created the earth in 7 days 5000 years ago
furthermore, he placed fossils and impact craters all over the place and in layers of the earth that correspond to eras in order to test our faith.
Never get tired of hearing that one. Or the even more odd part. Satan placed the fossils there to further test our faith.
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Russian Federation1381 Posts
On August 20 2009 15:43 FragKrag wrote:
I read in Dawkin's The Selfish Gene that it was possible for early ancestors (loosely used) of DNA (simple replicators) could have existed for the sole purpose of replicating, and when they began competing for resources, they started to "attack" each other, and many made protein armor out of the amino acids. Sounds possible and very interesting to me :O
Very interesting, our life truly resolves around competition. We really do compete all the time in everything, just as every other living organism out there that is always in the competition for survival and other things. It's really a sense of rivalry that made us what we are, not blind unity, tolerance and teamwork.
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Yeah, the entire book revolved around the fact that every organism is driven by competition and the preservation of their genes. It's a great read and it was very interesting how he presented what he thought.
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I once tried to explain abiogenesis to my English class.... I have learned that if college students cant follow ... no wonder creationists are able to persuade so many people.
Me: Okay now if all the elements required are present... chemical evolution would allow the basic building blocks of life to evolve ...
Them: Evolution?! You said abiogenesis and evolution were two completely different issues?
Me: But they are...
Another Dude: HE LIES... There was this one dude who created everything ...
Them: Oh that is much easier to follow.
Me: /facepalm
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Just to add something: I believe in the bio-chemical evolution too.
As for the call-creation: the cell membrane consists of phospholipides. And they tend to make oil bubbles in water. There is a theory that the nucleotides and the amino acids made it into the oil bubbles and were thus defended in a way. It is also known that certain molecules can pass the phospholipid barrier and it's possible that those molecules joined the amino acids and the nucleotides. It's just a theory but it makes sense.
Sad to say this but I think people are never going to know for sure how life came on earth or how it originated for sure.
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On August 20 2009 13:24 Astray wrote:
This is going to start a huge debate of creation v.s. evolution.
hahaha.
REALLY? O.O
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EPT
