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Author | Topic: Miller and Urey Experiment: What has changed? | |||||||||||||||||||||||||||||||||||||||
Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2 |
Ardent Enthusiast writes: This theory was based on the Miller/Urey experiment, which took place in 1953. My question is, why hasn't any new data been gathered on this topic, and if it has, why is it still being taught at the high school/college level? While there's still nearly as much uncertainty today as a half century ago, the field *has* progressed a great deal since then. This seems like a perfect description of 50 year-old thinking:
In my AP Bio class, we went through the origin of life on earth, how lightening struck chemicals on primordial earth, and how amino acids were formed and these became the first proteins and nucleic acids which eventually became the first Prokaryotic cell, etc. This makes me very curious about the materials being used in your AP biology class. Could you scan these materials in and make them available to us here? To try to briefly answer your question, while nothing in that description is necessarily wrong, it doesn't really accurately reflect modern thinking on the orgin of life on earth. It happened nearly 4 billion years, and after all that time there is very little evidence. Research since Miller/Urey has been very active and come quite a long ways, but we still know very little. Modern speculation on the subject is very circumspect, and no recent responsible presentation would offer a simplistic scenario like the one you described without making clear that it's just a very simplified and speculative summary of one possibility for abiogenesis (origin of life). --Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2 |
Ardent Enthusiast writes: I do not have a scanner. I do know people who do, however, and I will scan some pages as soon as I can. That'd be great. Keep in mind that the passage from your opening post that made me curious about these materials was this one:
Ardent Enthusiast in Message 1 writes: In my AP Bio class, we went through the origin of life on earth, how lightening struck chemicals on primordial earth, and how amino acids were formed and these became the first proteins and nucleic acids which eventually became the first Prokaryotic cell, etc. The reason this caught my attention is that while high school biology classes are not the proper place to get into the nuances of modern conceptions of abiogenesis, it would still be misleading to present the above scenario as if it were something we were pretty sure of. And it would be surprising if the source were a book with Ken Miller's name on the cover.
Anyway, what is this experiment doing in a 2006 Biology book? Especially alone in a 2006 Biology book. There is no mention of any other experiments relating to life on early Earth in this book. The Miller/Urey experiment was landmark! Historic! Revolutionary! It changed our thinking about life's orgins. You can only discover this new scientific paradigm once. Miller/Urey is in the same class of experiments as Galileo's falling objects experiment at the Leaning Tower of Pisa, the Michelson/Morley experiment that showed the ether didn't exist, the Millikan oil drop experiment that revealed the charge of the electron, and the Eddington measurements of starlight deflection during an eclipse that provided confirmation of Einstein's general theory of relativity. There were subsequent experiments in all these cases, but the ones that get mentioned time and again, the ones that are remembered, are the ones that first changed our thinking and let man's understanding of the universe take another step forward. You can use Google (and Google Scholar if you're of a technical bent) to find scads of information about subsequent work in abiognesis. There are also some good books, including a very recent one that is a survey of recent abiogenesis research called Gen-e-sis: The Scientific Quest for Life's Origins by Robert Hazen. --Percy This message has been edited by Percy, Thu, 04-13-2006 09:20 AM
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2 |
For a few directly related references, check out Recent Related Studies over at the Wikipedia article on the Miller/Urey experiment. For a much broader view of work on abiogenesis try the Wikipedia article on Abiogenesis.
--Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2
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Hi LimpSpider,
You seem to have forgotten the question you asked, so here's your question:
LimpSpider writes: Simple question. What experiment has been conducted that expands successfully (as in the direction towards making life) Miller’s original experiment? Can I provide the references tomorrow? It’s night here. I pointed you to webpages at Wikipedia that contained references to papers about experiments that were follow-ons to the Miller/Urey experiment specifically, and to abiogenesis research generally. You asked if you could provide references tomorrow, and I assumed this was a rhetorical question, but since you haven't provided any references today I guess you were waiting for permission. You do not need permission to provide references. In fact, it's in the Forum Guidelines:
But given what you just posted I'm now getting the feeling that what you really meant to ask was whether we've successfully synthesized life in the lab. The answer is no, not yet. --Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2
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I believe I have added to that what I wanted to say. It is not a contradiction. The extensions to M-U, I would not consider new. You seem to be having a lot of problems with simple definitions. In another thread you didn't seem to know the meaning of "extrapolation", and now in this thread you don't seem to understand the definition of "new". If a paper contains findings and information not in the original Miller/Urey paper, then those findings and information are necessarily new. Saying "I would not consider [them] new" reflects a problem with simple English. I think what you probably meant to say was that you were expecting papers that reflected more substantial progress toward the synthesis of life and that you didn't find that. --Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2
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LimpSpirder writes: Actually, I’ve never seen a virus evolve the ability to metabolize. First, understand that no one is proposing that metabolizing life evolved from viruses, not that that isn't a possibility deserving of consideration, but no one here is making that argument. Ringo was only saying that there can be gradations of life, that some "organisms" can have some but not all of the qualities of life. But second, I'm concerned about the "I"ve never seen" part of your message. To put the concern in a context familiar to you, have you ever seen Noah's flood? Have you ever seen Jesus resurrected? How much of the things that you think you know have you ever seen? You may want to do some thinking and investigating about the actual methods scientists employ to establish confidence in what they think they know. --Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2
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The concern has nothing to do with historical versus experimental or observational science. You said you had never seen a virus evolve metabolizing ability, and I responded with Biblical examples because I thought they would be more familiar to you, but let me remove the confusion with different examples. Would you object to the possibility of water on Mars because, "I've never seen water on Mars"? Would you object to the possibility of electrons because, "I've never seen an electron"? Would you object to the possibility of mountains eroding away to plains because, "I've never seen a mountain erode away to a plain"?
In other words, "I’ve never seen a virus evolve the ability to metabolize," is no objection at all, but if you think it has validity then discussion with you is pointless. That's why I said it was concerning. I was afraid you were adopting the position that if you had never seen something happen with your own eyes that it was not possible. So what did you really mean when you said, "I’ve never seen a virus evolve the ability to metabolize"? Was there a legitimate objection that you actually had in mind? --Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2 |
LimpSpider writes: This is not so with viruses. We can test if they metabolize. They do not. They have never been seen to do so (Via experimentation, when I say see, I don’t mean in the with my own eyes sense). By anyone. You did not say, "I've never seen a virus metabolize." You said, "I've never seen a virus evolve the ability to metabolize." If you had a legitimate point, what was it? --Percy
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Percy Member Posts: 22850 From: New Hampshire Joined: Member Rating: 7.2 |
LimpSpider writes: So I made a paraphrasical mistake. Okay, I guess you were forced into a tough choice between conceding you had no point or appearing clueless. Are you sure you made the right choice? Is there anything you'd still like to discuss about post Miller/Urey research into life's origins? --Percy
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