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Member (Idle past 1505 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
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Author | Topic: Information and Genetics | |||||||||||||||||||
wj Inactive Member |
quote: Perhaps you were right not to mention it. Here's some relevant comments by Gary S. Hurd atAccount Suspended "Unfortunately for Sarfati, reality intrudes again. In Noll et al. (1997) for instance it is learned that an atmosphere with less than 10% of the Earth's current oxygen level could have as much as 25% of the Earth's current ozone. Further, without any free oxygen, or ozone, there are several additional means available that could have protected early macromolecules, and life itself. For example, Cleaves and Miller (1998) observe that the prebiotic organic compounds in the oceans would easily absorb the UV radiation flux during the Archean (when the Sun produced less heat [IR radiation] and more UV than today). Earlier, Sagan and Chyba (1997) had shown that methane photolysis could have provided an effective ultraviolet radiation shield for the Earth and prevented, or minimized global glaciation. However, a third model exists, the occasional impact melting of frozen oceans on the early Earth (early to middle Archean approximately 3.9 Ga to 3.5, 1Ga=1 billion years before present) which provides oceanic organic chemical concentration, and an impact heat sink in addition to UV protection of prebiotic chemicals by ice (Bada et al. 1994). Indeed there is strong evidence that these processes could have begun during the Hadean as early as 4.4 Ga (Sleep and Neuhoff 2001, Wilde et al. 2001). " So UV dissociation of complex organic molecules may not be the problem which creationists suggest.
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Quetzal Member (Idle past 5898 days) Posts: 3228 Joined: |
Well, well, well. Welcome back, ChaseNelson. It took me some time to dig up that old thread, since you never replied to my last post.
As to your assertion that I failed to answer any of your questions, I think it would behoove you to re-read the thread in question. Please respond to: 1. my last paragraph on specified complexity and its problems 2. my citation of Dawkins and why your argument concerning what he said is erroneous 3. my examples of the immune system and cochlear system from the previous post which you have failed to address 4. the three references I provided concerning the evolution of biological information 5. my challenge to you to either accept MY definition of information or provide an operational one of your own As to your claim that I failed to respond to the final paragraph you cut-and-pasted from some creationist website, I stand by my contention that the paragraph has NOTHING to do with the topic - information and biology - and is rather a transparent attempt to divert the discussion into an abiogenesis/origin of chirality and the availability of oxygen in the early atmosphere. You don't even cite the references on your own - one of them ends in the middle of a sentence, showing not only didn't you READ the references, but merely cut and pasted the whole argument from someone else. If you want to discuss - we'll discuss. However, this time around there's going to be absolutely no tolerance on my part for straight cut and paste. If you can't synopsize in your own words the arguments, then all you're doing is re-hashing something someone else wrote - and which you may or may not understand. If you don't want a discussion under those constraints, fine. At least I won't have to wonder for three months what's going on.
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derwood Member (Idle past 1902 days) Posts: 1457 Joined: |
quote: Me too. I tend to 'cycle' between different boards. That and, after all, it is summer![quote]
SLPx:
quote: But that is a non sequitur. Inferring that something was designed (how is that done?) is not examining it. How does one conduct experments to test whether this inferred design really is design? And would not the creationist claim design if/when experiments were performed to show that it can occur naturally? Thios caveat is, in fact, already in place and has been employed by creationists since the early 1970's. Randy Wysong, creationist veterinarian, wrote a book in I think 1972 (The Creation Controversey, or something like that) in which he wrote that life had been created in the lab (news to me) but that rather than it being evidence for natural processes, it was evidence for design. After all, scientists had to add "KNOW HOW" (emphasis his) to the mix to get it to work. This same escape clause has been used on discussion boards recently, in fact. It was claimed by a creationist that indicing speciation in a lab would be a "good place to start" so that we can see how much "intervention" is required. That is, no matter what, the creationist will cry Design!quote: "As we know it." Do we know what the original life was? Do replicating molecules qualify? If so, where are their proteins? Do viruses have these 19 proteins? Do you KNOW that "none others" can support life?Here is an analogy: I am going to hang a picture on a wall. I ask my kid to bring me a screwdriver. He brings me a cross-tip. I ask him to bring me some screws. He brings me a box full of assorted screws of every type. I fish around in the box and pull out a hex head. No good. A flat-blade type. No good. A socket head. No good. Ah! A cross-tip screw, the only one I can use. Does this mean that the only screw types that will hold pictures on walls are cross-tips?quote: You missed the point...quote: But THAT is the question, is it not? You are saying that these things DO contian detectible design. Who detected it? How was it done? Where can I read this myself? I do hope, however, that you are not referring to Dembski's "filter"?quote: Why does it surprise you that I cannot answer your question? Do you think everyone should be conversant in biochemistry? I understand that any creationist with a degree in anything is an 'expert' in all areas of science by default. Sadly, I do not measure up. I, for one, would feel uncomfortable presenting myself as being 'expert' or even conversant in an area that I am not. But, see my screw analogy above for handedness...quote: Allow me to emphasize: "I'm just saying that what we know about what life needs today..." Do we know that what we need today was what the first life needed? Subsequent life? I read recently an analogy to a modern automobile. A modern automobile requires certain things to run. If we just start taking parts out, pretty soon - maybe even immediately - the car stops running. Does this mean that the a Model T NEEDED the same parts?quote: I've read some of Meyer's online essays and I find them fairly innocuous. At least he didn't analogize 'Darwinists' to Communists, like Wells does in his 'Icons...' video...
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derwood Member (Idle past 1902 days) Posts: 1457 Joined: |
Perhaps of interest to Chase and others (re:chirality, other stuff):
This is from a post by Tim Thompson on a board that is now defunct: Racemic amino acids from the ultraviolet photolysis of interstellarice analogues Nature 416: 401-403, March 28, 2000 Max P. Bernstein, et al. Abstract: The delivery of extraterrestrial organic molecules to Earthby meteorites may have been important for the origin and early evolution of life. Indigenous amino acids have been found in meteorites - over 70 in the Murchison meteorite alone. Although it has been generally accepted that the meteoritic amino acids formed in liquid water on a parent body, the water in the Murchison meteorite is depleted in deuterium relative to the indigenous organic acids. Moreover, the meteoritical evidence for an excess of laevo-rotatory amino acids is hard to understand in the context of liquid-water reactions on meteorite parent bodies. Here we report a laboratory demonstration that glycine, alanine and serine naturally form from ultraviolet photolysis of the analogues of icy interstellar grains. Such amino acids would naturally have a deuterium excess similar to that seen in interstellar molecular clouds, and the formation process could also result in enantiomeric excesses if the incident radiation is circularly polarized. These results suggest that at least some meteoritic amino acids are the result of interstellar photochemistry, rather than formation in liquid water on an early Solar System body. Amino acids from ultraviolet irradiation of interstellar ice analoguesNature 416: 403-406, March 28, 2000 G.M. Muoz Caro, et al. Abstract: Amino acids are the essential molecular components of living organisms on Earth, but the proposed mechanisms for their spontaneous generation have been unable to account for their presence in Earth's early history. The delivery of extraterrestrial organic compounds has been proposed as an alternative to generation on Earth, and some amino acids have been found in several meteorites. Here we report the detection of amino acids in the room-temperature residue of an interstellar ice analogue that was ultraviolet-irradiated in a high vacuum at 12 K. We identified 16 amino acids; the chiral ones showed enantiomeric separation. Some of the identified amino acids are also found in meteorites. Our results demonstrate that the spontaneous generation of amino acids in the interstellar medium is possible, supporting the suggestion that prebiotic molecules could have been delivered to the early Earth by cometary dust, meteorites or interplanetary dust particles. Just to make the story complete, earlier studies on the stability ofamino acid molecules in space are encouraging. Once formed, they are subject to fairly rapid destruction by the same UV that made it possible, unless they are protected in ice mantles on interstellar grains, or in a dense cloud protected from UV (The photostability of Amino Acids in Space, P. Ehrenfreund et al., Astrophysical Journal Letters 550: L95-L99, March 20, 2001). There is also evidence, as suggested in both papers, that if the UV impacting the ice is circularly polarized, the result could be a non-racemic product. There is some experimental evidence to support this view (Mechanism of pH-dependent photolysis of aliphatic amino acids and enantiomeric enrichment of racemic leucine by circularly polarized light, H. Nishino et al., Organic Letters 3(6): 921-924, March 22, 2001), and it is also evident that the necessary environment can be found in space (Astronomical sources of circularly polarized light and the origin of homochirality, J. Bailey, Origins of Life and Evolution of the Biosphere 31(1-2): 167-183, Feb-Apr, 2001). |
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Peter Member (Idle past 1505 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
... but is there actually any information content
of DNA, or is it just the way we view it?
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derwood Member (Idle past 1902 days) Posts: 1457 Joined: |
quote: Good question. I think that most would say that yes, DNA contains information. However, I don't think anyone competent in any related field would claim that the information in DNA is anything like the 'meaning' definition that creationists append to it.
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Tranquility Base Inactive Member |
Peter & SLPx et al
I think we all agree that genomic sequences are 'special' - they're not random - who cares how they came to be - they are special now - they code for folded and function proteins. You guys believe that you can get a minimal genome randomly and then that this genome will, over time, end up with new genes that will form organs, limbs and cellualr systems etc. This is where the debate should be focused. Surely we all agree that what we now have in genomes is special and finely tuned. As we have discussed before, in itself the genomic sequence and the protein sequences look pretty random. But train a neural netweork on it and it will find a systematic lack of randomness. a neural netweork would discover consecutive codons coding for alpha-helical secondary structure and simlar streches for beta-strands. There is definte informaiton content even if analysed by something that doesn't know what to look for. This is exactly the same with a computer. Examining a hard disk in binary it would look loke junk. In ascii one would find patterns. [This message has been edited by Tranquility Base, 08-12-2002]
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Peter Member (Idle past 1505 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
But with a hard-disk we start with the assumption that
the data on it was put there by someone ... and the binary digits stored are data not information. The main reason that I started this thread was to discuss the line of reasoning put forward by some YEC's that the informationcontent of DNA is an indication of design. DNA contains sequences that are used in the cell to createproteins etc. and that process in itself is pretty complex, but does DNA actually, objectively contain information (can you even have objective information?) ? The issue of information and genetics is important in theconsideration of design ... but is extremely complex, compounded by the abstract nature of information. Another contention, within the context of the information = designline of reasoning, is that information has to come from an intelligent source. Is this true? If I write a computer program to randomly generate a three lettersequence, and eventually that comes up with 'cat', and english reading individual will read that sequence and glean information from it ... it is related to all things feline in the consciousness of the observer. There is no intelligence behind the emergence of the sequenceabove, the intelligence is in the observer, who assigns meaning to it, and thus forms information.
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monkenstick Inactive Member |
i'll sum up how I see the whole genetics/information/ID argument
Step 1) formulate a series of rules about what information is, does and can do, based on man-made forms of information Step 2) Identify DNA as a form of information Step 3) Apply the rules we made for information to show that DNA can't do what the evolutionists say it ca
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Peter Member (Idle past 1505 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
If I have a group of chemicals and I put them together
in a flask, give 'em a whisk, add some heat energy maybe, and they react to form something else ... does that mean that the starting molecules contained the information required to perform the reaction? |
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Tranquility Base Inactive Member |
Peter
I partially agree/disagree. A study of genomes would discover systemtic non-randomness even without knowing what to look for. This is evidence of specialness which indludes design but I agree it is not proof of design.
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Quetzal Member (Idle past 5898 days) Posts: 3228 Joined: |
quote: Hi TB: I actually partially agree with this (removing the word "design"). There is no question that genomes are pretty well adapted to their current function. Although a case could be made (and has been) that many of the non-coding sections in the genomes of various organisms are pretty good evidence that "random" substitutions and duplications do exist (I'm thinking of the Alu sequence repetition in humans repeated over a million times; the so-called "satellite DNA" in Drosophila which consists of a seven bp sequence repeated 11 million, 3.6 million, and 3.6 million times - comprising over 40% of the genome). Even if these sequences have a structural function now, it may be a question of evolution making use out of something originally "useless". The other issue with your statement, of course, is to justify the use of the terms "finely tuned" at all. Obviously a leopard or human wouldn't be a leopard or human if their respective genomes didn't "code" specifically for the products necessary to build a leopard or human, by definition. In that sense, of course they're "finely tuned" (to state the obvious). If they sequenced any other way they wouldn't build leopards and humans (duh). (A rose by any other sequence wouldn't be a rose). On the other hand, if by "finely tuned" you mean "perfect" or even "approaching perfection", then you are way off base, and the nonsense sequences present in every genome investigated to date falsify the "perfect" genotype argument. Which in a round-about way, brings me to my point. The only way we are justified in asserting that the genomes of modern, living organisms are "finely tuned" is by understanding that their current form/sequence represents the end product of billions of years of evolution. Modern organisms with genomes which promote their survival are the beneficiaries of millions of generations of survivors. The organisms whose genomes weren't "finely tuned" for their particular environment and lifestyle aren't around any more. Moreover, simply because the genotypes appear finely tuned NOW, doesn't necessarily mean that a given genotype won't be selected out in the future if conditions change.
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Tranquility Base Inactive Member |
Hi Quetzal
I basically agree. The fine-tuning is at various levels of course and I agree that it is happening today via natural selection. I simply don't beleive the ribosome was finally tuned from nothing!
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Lewissian Member (Idle past 4752 days) Posts: 18 From: USA Joined: |
Deleted.
Edited by Lewissian, : Outdated.
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Quetzal Member (Idle past 5898 days) Posts: 3228 Joined: |
[QUOTE]Originally posted by ChaseNelson:
Hello, I am by no means back as this is the first day of a hectic school year. Yes, SLPx, I know exactly what you mean--I find time for one board, and then things get busy again so I end up skipping around.[/b][/quote] Good luck with school. Hopefully you'll have the opportunity to actually respond to my final post on the original thread.
quote: Really? How interesting. You are to be congratulated on laboriously retyping all those quotes. Perhaps to avoid such misunderstandings in the future you might want to consider synopsizing in your own words and simply reference the articles.
quote: That wasn't ad hom. An ad hominem attack would be to call into question your honesty and maturity directly - for example by calling you a liar for cutting and pasting a direct Phillip Johnson misquote of Dawkins here. I'm sure since you are quoting directly from the original source you are fully aware that the ellipses cover 16 full pages (part in the preface, part on page 2, and part on page 18!) - which represents one of the largest ellipse gaps I've ever seen - and weren't drawn from page 2-3 of the book as you cite in your reference. Johnson's misquoting can be found here. Anyone notice the similarities? However, since I don't engage in this type of tactic, I won't bring it up. Hopefully someday you will decide to respond substantively. In the meantime, enjoy school. [This message has been edited by Quetzal, 08-28-2002]
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