Viable Mechanism for evolution?
If natural selection, mutations, polyploidy, and gene replication/duplication do not add new functional genetic information to DNA (they only delete, scramble, and copy existing information), then how exactly do you account for the astronomical increases in information required to arrive at human DNA with over 3 billion base pairs? And when I say that they copy information, this is subsequent to photocopying a page out of a book; no new information is added. Also, assuming you present a mechanism (which we do not currently observe), how would evolution accomplish this even within 3 billion years, unless it added at LEAST 1 necessary, coherent, and functional piece of information to this DNA every year? Finally, this does not even account for the proteins necessary to carry out instructions for the genome, the role that they play in eukaryote cells, the process of meiosis necessary for sexual reproduction, or the replication of 100 trillion cells necessary to produce a human.
Also, although you may ASSUME that SOME unknown mechanism caused 1 perfectly functional change that was coherent to the DNA molecule without destroying the integrity and functionality of the entire molecule every year (which is a ridiculous assumption anyways), what motive and reasoning do you give to this mechanism (without inferring intelligence) to continue to build upon this structure of highly ordered complex information to get to this point? Finally, without any observable evidence of this happening today (remember, all those listed only delete, scramble, and copy existing information) how can you claim that this (evolution) is a scientific fact? Please respond using only logical answers and references to ACTUAL increases in functional genetic information (not including polyploidy, gene duplication, etc.), otherwise I will assume you are just another brainwashed evolutionist. Thank you.
Saying that scrambling and copying “absolutely do create new information” is an assumption based on your beliefs, not the actual evidence. Once again, what mechanisms do we CURRENTLY OBSERVE that add new information? Our observations of mutations that result in transcription errors have never produced these needed changes; so you’re resorting to your faith in the necessity of these happening, not factual occurrences.
Anything that cannot be construed as intelligently and purposely guided sorting of information (which is why they are called ERRORS) can certainly legitimately be called “scrambling,” because it relies on random changes. You observe replication processes because DNA was designed to allow for this, but your contention that it was the necessary driving force behind the mechanism for evolution is only hearsay. Any change that is not immediately beneficial to the genome of the organism is either neutral or detrimental. If you were to change one or two base pairs randomly, this would be detrimental to specific protein sequencing, and thus could easily result in partial or non-functionality of the cell. In the case that it actually is beneficial, such as sickle cell anaemia preventing malaria, it is still represented by a loss of information. Also, this loss of information on its own would certainly still be considered detrimental to the organism in question.
New information is not the issue here; it is functional information that is specific to the coherence of the coding process for certain proteins. For example: if you have the word CAT, and you randomly add characters to it, you cannot arrive at the word CATCHER unless you have specific letters that make the word coherent and meaningful. This does not even take into account the fact that this particular word, and the letters that are used in it, are both part of a structured, intelligently designed language system called English. Incidentally, if you add random Arabic letters to the end of CAT, you are never going to get the word CATCHER, in one coherent language. It just isn’t possible. The same is true of changes in DNA structure, in that they must be coherent to the language of the genome in order to make sense and function correctly.
Your contention that trichromatic color vision was produced naturally via mutations is purely speculative, and is in no way different than the argument that they were designed that way. Presumptions about hypothetical processes that you HAVE to believe occurred in order to validate your theory do not count as empirical evidence for your case.
Your assertion that natural selection strictly builds is patently false; in fact, quite the opposite is true. Natural selection selects from readily available genetic information in an organism, it does not add anything. It is a preservative feature used to allow adaptive characteristics to be selected for in specific environments for survival; but these traits are all pre-coded into the DNA structure prior to this selective process. The argument of “better or worse” is purely one of semantics, as it matters only whether this process is representative of a gain in coherent, functional, genetic information or not, which it is not.
It’s easy enough for you to say that duplications plus alterations equals the mechanism, but all the observable evidence points to only a loss, scrambling, and copying of existing information, not an increase. Although I applaud your effort, all you supplied me with was a bunch of handwaving and hyperbole, not real life examples.
Sorry, I only get 1000 characters to play with here, but I hate to leave anything out.
Okay, let me repeat it just once more: New information is not the point! It is a matter of new *functional* genetic information that is *coherent* to the coding process and the genome as a whole. If you photocopy a page out of a book and then scramble random letters throughout the text, the overall coherency of the specific information is not added to, it is taken away from. I’m sorry to inform you that truth is not contingent on the overall appeal to the “scientific community,” but rather stands on its own, above the illogical conclusions of fallible man.
The example of CAT was a very simple analogy of the necessity of the coherency of information, but barely touches on the overwhelming complexity of a molecule of DNA and its role within the cell. You seem to think that evolution is subsequent to an inventor tinkering away, swapping bases one by one to see if they result in functionally viable outcomes for the molecule. What you have to understand, is that the coding process is specific for the functionality of the cell; meaning, if a certain base configuration translates into a pre-planned function of the molecule, then changing this configuration only inhibits normal function. An accidental scrambling or substitution of bases does not increase the intrinsic worth of the molecule itself or the cell as a whole, because it already has a designated set of protocols that it was created to carry out.
In fact, these transposons you refer to are comparable to viruses due to their mutagenetic propensity to corrupt the gene in question, causing a myriad of diseases such as “hemophilia A and B, severe combined immunodeficiency, porphyria, predisposition to cancer, and Duchenne muscular dystrophy (Wikipedia).” A good analogy here might be a well-designed car swapping out its rubber tires for stone tires. Certainly you are substituting “information” to some degree, but you are not improving upon the intended design; on the contrary, you are inhibiting normal function. The Arabic letters analogy was meant to point out that information that is contained within the genome is written in a specific language–vis-à-vis the language of English–and therefore requires an intelligent agent in order to add coherent letters, words, or sentences, represented within the genome by bases.
Of course you assume that the structured language used for DNA arrived arbitrarily; and also that this “created” language was able to produce the “book” of human DNA which is subsequent to over a thousand encyclopedias, quite by accident. But I’m sure random, meaningless processes which utilize haphazard trial-and-error methods could easily arrive at such incredible coherent information; so pardon me so very much for resorting to logical inferences of design. After all, if there is a god, and I’m sure it’s the one you claim to serve (‘cause it ain’t my God), he must be a real retard! But dang that evolution sure is a genius!
Evidence is what we interpret based on whatever our presuppositions are. This is especially true regarding events in the past that we cannot observe. Homology arguments are simply extrapolations of an a prior belief in naturalism. You might notice how many times the say “may have” or “may also” throughout the paper, if you look closely. I’m not disputing the credentials of the scientists here, only the main assumptions that they started with, and there also their conclusions.
Just the same, if I listed a paper by four PhD creationist scientists (educated at secular universities) validating the logical inferences of irreducible complex structures in nature, you would surely produce the same argument in your defense. But for some reason it is only viable when your assumptions are upheld by interpreting them through your own evolutionary filter. So yes, I stick with my original claim of handwaving and hyperbole. And now to that I guess I can add a fundamental misunderstanding of natural selection as well.
- secretsauceLv 71 decade agoFavorite Answer
>"If natural selection, mutations, polyploidy, and gene replication/duplication do not add new functional genetic information to DNA ... "
Wrong assumption. While it is debatable whether any of those things *by itself* produces "new information" (depending on what your definition of "new information" is), it is clear that those things *in combinations* absolutely do ... by *any* definition of "new information."
>"(they only delete, scramble, and copy existing information)"
Two of those things ... "scrambling" and copying of existing information, when they happen *in combination*, absolutely do create "new information." Here's why:
First, let's look at that word "scramble". You're trying to stack the deck by implying that any transcription error *must* randomize information to the point of complete useless non-functionality. That is simply not true. Something as small as a change in one or two base pairs may simply change the properties of the resulting protein a small amount ... maybe slightly worse, maybe slightly better ... but still within the parameters of being functional. So calling this "scrambling" is unfair.
As far as "copying" ... absolutely, this occurs. But why do you rule out gene duplication? Making an extra copy of a gene perhaps does not create "new information" *BY ITSELF* ... but coupled with even a single base-pair change that alters the property of the resulting protein, a gene duplication + base-pair change produces a NEW GENE ... which is "new information" by any definition.
So right there is a perfectly viable mechanism for evolution:
1. A gene is copied (gene duplication). The duplicate may be harmful, beneficial, or just neutral (just a redundant copy).
2. One of those genes is altered slightly (transcription error in one or two base pairs ... perhaps many generations later).
3. Result ... two genes, where once there was one. Dat's "new information", baby.
4. If that "new information" is also "good information" (i.e. confers some benefit), then that new information will propagate into the population. Dat's evolution, baby.
As an example, that appears to be how we have three-color vision. The opsin gene that produced the photopigment that reacts to long wavelengths (LW) of light, was first duplicated, producing a redundant copy of the LW opsin. And (generations later) a small change to the peak wavelength of one of the copies, changed the peak wavelength of the resulting protein to medium wavelengths (MW) of light ... a *new protein* (new photopigment). This is how primates went from two-color vision (Short and Long wavelengths) to three-color vision (Short, Medium, and Long wavelengths). And this particular gene duplication+change can be traced in primates back to *after* the split between Old-World primates (African and Asian monkeys and all apes, including humans) and New-World primates (the Central and South American Monkeys). (See source.)
Going from two photopigments to three photopigments is "new information" by any definition.
>"what motive and reasoning do you give to this mechanism (without inferring intelligence) to continue to build upon this structure of highly ordered complex information to get to this point?"
No motive needed. No inferring of intelligence needed. The mechanism is a little thing called natural selection. Natural selection *BY DEFINITION* can only *build* upon the current structure ... it cannot diminish it, much less destroy it. While mutations themselves can be either harmful or beneficial ... natural selection selects *only* the beneficial ones. So even if 99% of mutations were harmful, and 1% are beneficial ... it's *ONLY* the beneficial ones that propagate. So over time, a structure will either stay the same, or get better; it cannot get worse.
Summary: mutation (e.g. duplication *PLUS* alteration) is the mechanism for producing "new information." And from that endless supply of "new information", natural selection is the mechanism that selects only the "good information." This always builds on existing structure ... it can only improve ... it cannot get worse. Add 3 billion years ... you do the math.
Look, the science of genetics is on my side. You claim that it is not "new information" ... and I ask, by what possible definition of "new information" is a new protein with different properties NOT "new information"?
Your CAT to CATCHER using Arabic letters analogy is off base. If DNA uses a language of four letter GATC, then you can get from CAT to TAG with a transposition + letter substitution ... the type of *combination* of mutations that is OBSERVED commonly in genetics, and which are able to occur without total collapse of functionality (although it may alter that functionality enough to provide a small harm, or a small benefit). Nobody's suggesting using Arabic letters ... only you.
>"Your contention that trichromatic color vision was produced naturally via mutations is purely speculative"
Purely speculative?? I did something rarely done on Y!A ... provided a *primary* source as evidence ... a scientific paper that lays out the *evidence* for my claim in excrutiating detail. I don't expect you to read it all, or even believe it all, just because four professors of molecular genetics from respected universties wrote the paper. I am not making an argument from authority ... but offering up *evidence*. I can't provide better evidence here on Yahoo Answers than these professional geneticists did with a detailed research paper ... but you just sniff it off as just "purely speculative" ... which shows the type of utter contempt for science and scientists that is impossible to argue with. *Any* example or evidence I provide is just dismissed with a wave of your hand.
And you accuse *me* of "handwaving and hyperbole." LOL
- Anonymous1 decade ago
to answer your first question, have you looked at a xerox copy of a book page? is it EXACTLY like the original? No it is not. Errors in copying occur, and the more copies you make of copies of copies of copies, etc., the more errors are made, until copies coming out look absolutely nothing like the original.
The same thing happens in gene replication. Mutations happen spontaneously during the replication process. Some times mutations happen in great numbers, and there is little in the environment to deselect their survival, but other times, such as the first billion or so years of life, mutations are usually less viable that the original and are discarded the same way you would discard your xeroxed book page if it was smudged so you couldn't read it.
Mutations happen all the time, sometimes they matter, sometimes they don't, sometimes they make a fatal error, sometimes they make an improvement, and sometimes the change doesn't affect the survival of the resulting organism, so the mutation survives in spite of not being an advantage. Other mutations can then build upon the first.
- 4 years ago
Under this scenario you would be obligated to teach every other creation myth that was requested. The problem is that Creationists want it taught as a viable alternative to science when it clearly is not. I don't want my tax money paying for someone to confuse my kids w/ nonsense. If they came out and said, "This is creationism, just remember it's not really true." the fundamentalists would have a fit. If a teacher taught it as if it was true all the reasonable people would object and sue the school board costing the taxpayers even more money. There is no compromise w/ Creationism in public schools.
- NimrodLv 51 decade ago
You begin with a false premise. Someone must be spewing out misinformation recently about mutations and information. Yours is not the first question posted here that proceeds from the idea (incorrect) that mutations only lose information.
It is also apparent that you do not appreciate the power of selection and non-coding RNAs. I don't feel like getting into a long discussion, (it's late) but you are mixing up different questions. One is how did life arise. That is the domain of abiogenesis, not evolution. Look up the RNA World.
Of course it is ridiculous to think that billions of nucleotides directly self-assembled into a fully functional genome. But that's not how it happened. Our genome is not descended from a pool of organic slime, we inherited the legacy of our primate ancestors. They in turn inherited the genome of the ancestral placental mammal, etc....down to the last common ancestor of all eukaryotes who in turn received the genome of the common ancestor of all living organisms on this planet. Along the way, a lot of selection, mutation, genome duplication/reduction have added to the available repertoire of tools for complex organisms to develop.
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- Anonymous1 decade ago
Mutations (including duplications of gene stretches and point mutations on them) provide changes in "information", including "increases in information". Natural selection selects from this information. It's very straight forward. And it is abundantly observed. It is very clear from all that you have written that you don't understand at all what you are talking about at all, don't have an honest defintion of "new information" anyway, are probably incapable of being logical about the subject, and have a total lack of respect for the people who have taken the time to try to educate you. Hence I'll just list a few of the countless instances that "increased information" has been observed in living populations and hope that you have the integrity to give secretsauce best answer.Source(s): Hughes, A. L. and Friedman, R. 2003. Parallel evolution by gene duplication in the genomes of two unicellular fungi. Genome Research 13; 5, p.794-799. Lenski, R. E., Rose, M. R., Simpson, S. C. and Tadler, S. C. 1991. Long-term experimental evolution in Escherichia coli. I. Adaptation and divergence during 2,000 generations. American Naturalist 138, p.1315-1341. Park, I.-S., Lin, C.-H. and Walsh, C. T. 1996. Gain of D-alanyl-D-lactate or D-lactyl-D-alanine synthetase activities in three active-site mutants of the Escherichia coli D-alanyl-D-alanine ligase B. Biochemistry 35, p.10464-10471. Prijambada, I. D., Negoro, S., Yomo, T. and Urabe, I. 1995. Emergence of nylon oligomer degradation enzymes in Pseudomonas aeruginosa PAO through experimental evolution. Applied and Environmental Microbiology 61; 5, p. 2020-2022.
- JardLv 44 years ago
viable mechanism evolution
- Anonymous1 decade ago
I will give you the simplest of examples. Bacterial conjugation. During this process, bacteria can transfer plasmids, which are not part of the bacteria's main chromosome. These can often become incorporated into the main chromosome and thus add hundreds, sometimes thousands, of new base pairs in a single shot. This is one of the many reasons bacteria become resistant to antibiotics.
- 1 decade ago
Actually it does add new information.
Natural selection, genetic drift, and gene flow are all mechanisms that can alter a population's genetics, and can indeed add new information.Source(s): http://talkorigins.org/indexcc/CB/CB102.html http://talkorigins.org/indexcc/CB/CB101.html
- Anonymous1 decade ago
the process of crossing over of chromosomes adds new genetic info. in addition, replication mistakes add new information. these have all been witnessed in the lab. mistakes during meiosis can also add info... in the extreme sense look at trisomy disorders such as down syndrome
- 1 decade ago
You're probably gonna hate this... but that's why I don't believe evolution. I prefer creationism. Makes waaaayyyy more sense to me :).
I've heard some people saying that the chance of life coming from evolution as we understand it now is basically the same chance as taking all the parts to make a watch, throwing them in a box, shaking it up, and getting a functioning watch out of it. Assuming that the parts haven't turned to dust before that happens.