Author
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Topic: Milley/Urey revisited
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Modulous
Member Posts: 7799 From: Manchester, UK Joined: 05-01-2005
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Message 1 of 9 (486232)
10-17-2008 9:18 AM
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quote: Miller's well-known experiments first done in 1952 used water along with methane, ammonia and hydrogen, the kinds of gases then thought to have dominated the Earth's oxygen-free atmosphere more than two billion years ago. His sparks turned the mixture red, then yellow-brown, and made a number of amino acids, including glycine and alanine, commonly found in proteins. But soon after, Miller had revised those experiments by injecting hot steam into the gas mixture, so that conditions resembled those you might find in an erupting volcano. These experiments were the ones that intrigued Jeffrey Bada. Because not long after Miller's original experiments, it became clear the Earth's early atmosphere was nothing like the "reducing" mixture simulated in his apparatus.
So far, so normal. However, the exciting thing is that some original samples have been found from these experiments. Including the revised experimental conditions that Miller had only written about in vague terms.
quote: "We started sorting through these, and lo and behold, we found a whole collection, almost a complete collection, of the extract samples from the volcanic experiments. And so we just went at it, using the state-of-the-art techniques we have today and analysed these samples." [says Professor Bada]
quote: Miller, using the old methods, had found five amino acids; Jeffrey Bada and his teams tracked down 22. What is more, the overall chemical yields were often higher than in the first set of experiments - the mixture appeared to be more fertile.
BBC News
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bluescat48
Member (Idle past 4180 days) Posts: 2347 From: United States Joined: 10-06-2007
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Message 2 of 9 (486245)
10-17-2008 1:49 PM
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Reply to: Message 1 by Modulous 10-17-2008 9:18 AM
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Highly logical. Good article.
There is no better love between 2 people than mutual respect for each other WT Young, 2002 Who gave anyone the authority to call me an authority on anything. WT Young, 1969
This message is a reply to: | | Message 1 by Modulous, posted 10-17-2008 9:18 AM | | Modulous has not replied |
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Coragyps
Member (Idle past 725 days) Posts: 5553 From: Snyder, Texas, USA Joined: 11-12-2002
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Message 3 of 9 (486717)
10-23-2008 10:44 PM
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Reply to: Message 1 by Modulous 10-17-2008 9:18 AM
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I can email pdf's of the Science paper to anyone interested. Zephyr, how's Camp Taji treating you?
This message is a reply to: | | Message 1 by Modulous, posted 10-17-2008 9:18 AM | | Modulous has replied |
Replies to this message: | | Message 5 by zephyr, posted 10-24-2008 5:33 AM | | Coragyps has not replied | | Message 6 by Modulous, posted 10-24-2008 8:54 AM | | Coragyps has not replied |
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Deftil
Member (Idle past 4446 days) Posts: 128 From: Virginia, USA Joined: 04-19-2008
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Message 4 of 9 (486723)
10-23-2008 11:50 PM
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Reply to: Message 1 by Modulous 10-17-2008 9:18 AM
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Holy crap. That's awesome news.
This message is a reply to: | | Message 1 by Modulous, posted 10-17-2008 9:18 AM | | Modulous has not replied |
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zephyr
Member (Idle past 4540 days) Posts: 821 From: FOB Taji, Iraq Joined: 04-22-2003
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Message 5 of 9 (486732)
10-24-2008 5:33 AM
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Reply to: Message 3 by Coragyps 10-23-2008 10:44 PM
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Aside from the fact that it's apparently rendered me totally illiterate (I really did look for this thread before proposing a new one), I'm having a great time. I would absolutely love a copy of the paper... "thefisherking at gmail dot com" (still wondering why this isn't in "Origin of Life" btw) Edited by zephyr, : No reason given.
This message is a reply to: | | Message 3 by Coragyps, posted 10-23-2008 10:44 PM | | Coragyps has not replied |
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Modulous
Member Posts: 7799 From: Manchester, UK Joined: 05-01-2005
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Message 6 of 9 (486738)
10-24-2008 8:54 AM
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Reply to: Message 3 by Coragyps 10-23-2008 10:44 PM
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That would be fascinating, thanks. My email should be not so cunningly hidden behind the mail button.
This message is a reply to: | | Message 3 by Coragyps, posted 10-23-2008 10:44 PM | | Coragyps has not replied |
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Stile
Member Posts: 4295 From: Ontario, Canada Joined: 12-02-2004
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Message 7 of 9 (486786)
10-24-2008 3:18 PM
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Reply to: Message 1 by Modulous 10-17-2008 9:18 AM
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Some musings
Modulous writes: Miller, using the old methods, had found five amino acids; Jeffrey Bada and his teams tracked down 22. What is more, the overall chemical yields were often higher than in the first set of experiments - the mixture appeared to be more fertile. So, if I follow correctly: 1. Some people have found samples from the Miller/Urey experiments that are 50 (or so) years old. 2. When Miller/Urey analyzed the samples, they found 5 amino acids. 3. When present-day people analyzed the samples, they found 22 amino acids. Are they saying that the samples were more successful because the present-day equipment found things that 50 year old equipment did not find? That is... the 22 amino acids were present 50 years ago, just not detectable by Miller/Urey? Or (and I find this much more impressive) are they saying that the samples are more successful than previously thought because those 5 amino acids in the samples have gone on to evolve into (or somehow otherwise create) 22 amino acids on their own over the last 50 years? Is it possible to tell the difference?
This message is a reply to: | | Message 1 by Modulous, posted 10-17-2008 9:18 AM | | Modulous has replied |
Replies to this message: | | Message 8 by Modulous, posted 10-24-2008 6:08 PM | | Stile has seen this message but not replied | | Message 9 by Coragyps, posted 10-24-2008 7:55 PM | | Stile has seen this message but not replied |
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Modulous
Member Posts: 7799 From: Manchester, UK Joined: 05-01-2005
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Message 8 of 9 (486810)
10-24-2008 6:08 PM
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Reply to: Message 7 by Stile 10-24-2008 3:18 PM
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Re: Some musings
Are they saying that the samples were more successful because the present-day equipment found things that 50 year old equipment did not find? That is... the 22 amino acids were present 50 years ago, just not detectable by Miller/Urey? Or (and I find this much more impressive) are they saying that the samples are more successful than previously thought because those 5 amino acids in the samples have gone on to evolve into (or somehow otherwise create) 22 amino acids on their own over the last 50 years? I think the former, rather than the latter, is what they were arguing for. If the 22 amino acids came along some time after the experiment, I'd suspect contamination rather than some revolutionary chemical evolution discovery Also: I'm not sure if they found the amino acids, or evidence of the previous existence of those amino acids.
This message is a reply to: | | Message 7 by Stile, posted 10-24-2008 3:18 PM | | Stile has seen this message but not replied |
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Coragyps
Member (Idle past 725 days) Posts: 5553 From: Snyder, Texas, USA Joined: 11-12-2002
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Message 9 of 9 (486829)
10-24-2008 7:55 PM
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Reply to: Message 7 by Stile 10-24-2008 3:18 PM
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Re: Some musings
the 22 amino acids were present 50 years ago, just not detectable by Miller/Urey? Exactly that. Miller looked for his by running paper chromatography and spraying ninhydrin on the paper with a scientific-looking Windex bottle - and probably turned some fingers purple in the process. State-of-the-art in 1953, but already near-obsolete by the time I got to college in '65. The new study's methods are at least 10,000 times as sensitive.
"The wretched world lies now under the tyranny of foolishness; things are believed by Christians of such absurdity as no one ever could aforetime induce the heathen to believe." - Agobard of Lyons, ca. 830 AD
This message is a reply to: | | Message 7 by Stile, posted 10-24-2008 3:18 PM | | Stile has seen this message but not replied |
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