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Author Topic:   PROOF against evolution
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 130 of 562 (46537)
07-20-2003 3:30 AM
Reply to: Message 129 by Buzsaw
07-20-2003 12:33 AM


Buzz writes:
quote:
That's all you're going to say, that you meant 2LTD instead of 1LTD? How does 2LTD make any more sense than 1LTD? 2LTD says that the entropy of a system can never decrease. 2LTD has as little to do with information as 1LTD.
I guess the old meaning of 2td and the new are different, the old having a more negative effect, including the information factor. I guess the question is whether the change was to accommodate or to enlighten.
2LTD has never changed to have "a more negative effect", there are only different ways of stating it. I chose the shortest. 2LTD has nothing whatsoever to say about information. Why do you think it does?
You still have repetitive salt, in spite of the errors. I would think logically that would still be more likely than random mutations which must each involve something different as well as productively positive so as to introduce information for natural selection. Does that make sense?
No, it does not make sense. Please perform this exercise. Copy the following lines of information 1,000 times. Each time you make a copy, be sure to copy only from the previous copy:
agctagcggtacagcgtggacctggtcaacggtagacagttcgatccgttcgatccatggtgccaactagttagct
atgatcgttagccatgtcatactgctaagtcaaattgccagctacctaactggccatagtctgatccgatctgatc
tttgacaggttgccacaacttcgacatgtcgacaccggttgtttcgtcatctatccggtaaacgttcgacttagct
Each time you make a new copy you are doing the exact same thing you did before, not "something different" as you claim above. And each time you make a copying error you create new information. DNA copying during reproduction is fairly analogous to this. There's no "magic extra something" happening every time there's a copying error. It's just chemistry.
quote:
Observing what, Buzz? The evolution of organisms on another planet? For the sake of argument, let's say there's other life out there in the universe. Let's even say it's on a planet orbiting the closest star. How would we observe it?
True. I should've narrowed that down to the other planets and satelites of the solar system.
Except that I already addressed this in an earlier email, saying that the earth is in a beneficial location, neither too far nor too close to the sun. At heart, life is just very complicated chemistry, and so conditions must be warm enough to permit chemical activity, but not so warm that chemical bonds can't form. You need to first examine other planets in beneficial locations like earth's, and only after finding no life on a statistically significant number of planets can your statement that we don't observe evolution elsewhere carry any weight.
quote:
And how about answering an earlier question that you ignored. If we happen to discover life on Mars or Europa, what would it mean to this claim of yours?
It would mean to me the same god saw fit to created life on both. I would then have one less of the other ss bodies to argue with you about.
I acknowledge the smiley, but you're using it to avoid addressing the issue. Your original argument makes no sense. You're arguing that evolution violates 2LTD, and that the lack of life on other planets in the solar system is evidence that evolution isn't happening on earth because it isn't happening on other planets. Since biological evolution only occurs in the presence of life, how does it make any sense to even bring this up?
Life is just complicated chemistry. If you look inside a cell there isn't anything supernatural going on, just chemistry. And everytime there's a copying error with DNA thereby adding information (which happens all the time, including in your own body), it's just chemistry.
I got the implication that by your suggestion it might be useful for me to come back and respond to some unfinished business. Sorry I disappointed you. I did the best I could with the time I had to put into it.
Why didn't you put the time you had yesterday and the time you had today and the time you had tomorrow into researching the issues so that the next day you could compose an intelligent response? If we hear from you again on this thread, I hope it's not before Wednesday.
--Percy

This message is a reply to:
 Message 129 by Buzsaw, posted 07-20-2003 12:33 AM Buzsaw has replied

Replies to this message:
 Message 131 by Buzsaw, posted 07-20-2003 12:21 PM Percy has replied
 Message 144 by DNAunion, posted 01-14-2004 9:52 PM Percy has not replied
 Message 147 by DNAunion, posted 01-14-2004 10:02 PM Percy has not replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 132 of 562 (46604)
07-20-2003 8:14 PM
Reply to: Message 131 by Buzsaw
07-20-2003 12:21 PM


Hi, Buzz!
Ya know, it's not Wednesday yet. Had you waited a few days and let your reply at least simmer in your mind a bit you might have produced something that made sense.
Buzz writes:
Creationists believe that the complex chemistry and all that's going on in the universe was originated and put in place by the supernatural. That does not mean we believe the chemistry itself which is going on is going on supernaturally as you are implying.
You started this conversation about information with arguments about RM/NS, so clearly we're talking about evolution, not the origin of life. You've never come straight out and said it, probably because you don't understand what Gitt (not Pearcey) is actually saying, but the way Gitt claims it works is that there is a law of entropy for information, and that random processes cannot create new information. This is obviously false since it has already been described for you how random processes can do just that, and without any supernatural intervention. And the fact that Pearcey, who *is* another Creationist after all, does not agree with Gitt at all on this matter should at least raise questions within your mind. And these questions might have occurred to you had you studied and contemplated a bit more. But no, you had to reply today.
I should think there are other creationists out there who are more educated...
It isn't your lack of education that is hurting you, because all the information you need is out there on the web. It is your reluctance to seek out this information and incorporate it into your understanding that is hurting you.
Maybe it's that they don't care to deal with the insults and arrogant attitude of some with whom they must contend with to do so.
The insults are regrettable, and you have shown yourself to be a far better gentleman than many here, myself included. But as for arrogance, no one here can hold a candle to you. The confidence, not arrogance, with which other people have expressed their understanding stems from evidence gathered over decades and in some cases centuries, and this evidence deserves the consideration it did not receive from you. Many people have spent much time explaining things to you, only to have it ignored or dismissed, usually on the basis of personal incredulity. This produces a certain amount of very understandable frustration as extremely few points ever seem to get across. It isn't that the people you're discussing with are right. Maybe they are, maybe they aren't. It's that your responses rarely indicate any understanding of what was explained, yet you dismiss the argument anyway. Further explanations are usually met with a determined ignorance, and you have occasionally commented that you don't have the time or background for this, but you believe you're right anyway. Most people at least have the good sense to avoid expressing and defending strong opinions of things they know little about. That you refuse to be guided by this is the height of arrogance.
--Percy

This message is a reply to:
 Message 131 by Buzsaw, posted 07-20-2003 12:21 PM Buzsaw has not replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 187 of 562 (87678)
02-20-2004 8:17 AM
Reply to: Message 181 by sonicxp
02-17-2004 5:25 AM


sonicxp writes:
Here's a book I recommend you read: The Evolution Cruncher by Vance Ferrell
This book is available for $5.00 from CSE Ministry (CSE stands for Creation Science Evangelism). It is not available from any of the three on-line bookstores I visited, Amazon, Borders and Barnes and Noble, though you can find it for $12.60 at some used bookstores. It appears to be self-published by Evolution Facts, and is a compendium of an encyclopaedia they call their Evolution Disproved Series.
But save your money, it's also available online.
Vance Ferrell's only other book is Cut Funeral Costs: Save 1000 on Every Funeral. He appears to be associated with organizations like Mission Evangelism and SDA-Defend, all out of Altamont, Texas.
--Percy

This message is a reply to:
 Message 181 by sonicxp, posted 02-17-2004 5:25 AM sonicxp has not replied

Replies to this message:
 Message 188 by PaulK, posted 02-20-2004 3:53 PM Percy has not replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 458 of 562 (134175)
08-15-2004 9:14 PM


Finally found time to check my email and discovered that Vxifix had replied to a message I posted last month. I've only skimmed the ensuing discussion, but what a silly attempt to disprove evolution: Evolution can't happen because we don't know how the semantics and symbols were defined and joined.
To me, the key fallacy in Vxifix's argument is his belief that meaning implies an intelligence creating that meaning, placing him firmly in the IDist camp. But at heart, biology is just complicated chemistry, and the processes that influence and modify the genetic code occur without any intelligent direction, and we've observed this taking place in the lab.
So Vxifix can argue all he likes that evolution is impossible because meaning has to come from somewhere, but allele frequencies and nucleotide sequences care not and continue changing over time.
--Percy

Replies to this message:
 Message 461 by yxifix, posted 08-16-2004 4:27 AM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 477 of 562 (134288)
08-16-2004 9:07 AM
Reply to: Message 461 by yxifix
08-16-2004 4:27 AM


yxifix writes:
All in all... I want to tell you only one thing -> Do NOT reply like this before you have read whole discussion!! Thank you.
Arguments like, "There has to be DNA for hair before there can be hair," did not originate with you. These are IDist arguments, and we see them here all the time. Your information argument isn't new, and I don't have to read the whole thread to know where you're coming from. The problem with your argument is that the very processes you say it disallows, namely allele frequency changing over time and mutation modifying and adding information to the genome, are both observed and inferred to happen.
I'd say I probably disagree with Pink Sasquatch about evolution not involving creation of information. The first life was billions of years ago, and that first life did not have DNA for eyes, teeth and eyes, so that DNA must have developed over time from some process, and that process is called evolution.
--Percy

This message is a reply to:
 Message 461 by yxifix, posted 08-16-2004 4:27 AM yxifix has replied

Replies to this message:
 Message 480 by yxifix, posted 08-16-2004 10:23 AM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 483 of 562 (134312)
08-16-2004 11:05 AM
Reply to: Message 480 by yxifix
08-16-2004 10:23 AM


yxifix writes:
Once again... give me clear explanation and example... how can an information "arise" ....I'm not talking about an information changed a little by "mutation". I'm talking about macro-evolution.
Macroevolution resulting in the origin of a new species derives from the accumulation of mutations over time. There is no memory in the genome to say, "We've changed enough from the original, and further changes are disallowed." If, say, a bacterial genome had accumulated 100 mutations over time, there is nothing keeping track of how many mutations the genome has already experienced to prevent additional mutations. In other words, there are no limits to the number of mutations a genome can accumulate.
We know that speciation occurs by at least a couple avenues. First, it has been both observed in the lab and in the wild. And second, fossils are a record of change over time. Well before Darwin it was already widely accepted that evolution had occurred, they just hadn't yet figured out the mechanisms.
We also have genomic evidence of speciation through DNA analysis. The genetic differences between closely related species indicate to us which mutations the genomes experienced as the two species drew further apart.
As I said... read whole discussion.... you are the only one who think evolution involves a creation of information... I'll be happy to discuss this with you !
So now you can tell me, how the initial information evolved. Thanks.
This is what I described in Message 99, which is the message you replied to in your first post to this thread. Let us say that these are all the alleles of the eye color gene in a population:
0001 blue
0010 green
0100 brown
Now a reproductive mistake produces a mutation in this gene, giving rise to an additional allele:
0001 blue
0010 green
0100 brown
1000 yellow
So now there are four alleles for this gene in the population instead of three. Mutation has produced additional information.
It wouldn't make any difference if the new allele resulted in an eye color that already existed, instead of a new color. The measure of information is the size of the set of messages, and our set of messages has just increased in size by one allele, and therefore there is now more information in the population's genome.
Of course, if the individual with this mutation fails to reproduce, then the mutation will die with him and the allele count for this gene in the population will decrease by one back to its former size.
--Percy

This message is a reply to:
 Message 480 by yxifix, posted 08-16-2004 10:23 AM yxifix has replied

Replies to this message:
 Message 489 by yxifix, posted 08-16-2004 8:27 PM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 494 of 562 (134496)
08-16-2004 9:34 PM
Reply to: Message 489 by yxifix
08-16-2004 8:27 PM


yxifix writes:
Percy writes:
Macroevolution resulting in the origin of a new species derives from the accumulation of mutations over time.
You don't know what you are talking about... This is just your rich fantasy, your assertion, nothing more.
I think it's more like bluster is your way of avoiding discussion, for otherwise you would explain why mutations cannot accumulate to the point of speciation and beyond. Allele frequency change and random mutation are processes that we observe taking place today, and so we conclude that those processes are responsible for speciation.
I've never seen anyone walk from Boston to San Francisco, but I've often seen people walk a considerable distance. From this I can reasonably conjecture that one could walk all the way from Boston to San Francisco. Someone could object that I've never actually observed anyone walking between these cities and that therefore it isn't possible, and silly as this would be it is the same as your claim that mutations cannot accumulate to produce significant change in organisms. Just as there seems nothing to stop someone stringing together enough steps to walk from Boston to San Francisco, there is also no apparent obstacle to stringing together enough mutations to cause speciation.
Maybe you can describe how a hand evoluted in stages through these small mutations, hm? ...well. not a hand, both hands in fact... that would be interesting reading.
Unraveling specific evolutionary pathways and aligning them with specific mutations for morphological structures like the hand is in many cases likely to prove impossible because mutations and allele frequency changes don't leave a paper trail. But we can be confident it developed through the same processes we observe taking place today.
Asking such questions is similar to asking how a particular grain of sand in the desert arrived at its current location. In most cases we would be unable to answer that question in any detail because there simply isn't sufficient evidence. But we can confidently say that it was due to geological and environmental processes, or perhaps it arrived off the sole of someone's shoe, and of course there are other possibilities. Someone could object that this is impossible to know because we have no evidence for that particular sand grain and that therefore it must have arrived there by some other means, but that would be ridiculous. It isn't much different to say that the evolutionary processes we see in action today could not be responsible for hand evolution simply because evolutionary processes do not leave hard evidence of specific evolutionary pathways behind.
And I'm asking you... why 0001 is blue, why it is not green or brown? THIS is the important question. Please read whole discussion (from page 18). I don't want to start it all over again.
I'm afraid I don't have any answers except the ones you've already been provided. But your question isn't relevant to the point I was making, something you would have realized had you read Message 99 more carefully. It had been asserted that random mutation cannot add information, and my example was an illustration of how random mutation can increase the amount of information in a population's genome. The example is valid no matter how codes align with colors.
--Percy

This message is a reply to:
 Message 489 by yxifix, posted 08-16-2004 8:27 PM yxifix has replied

Replies to this message:
 Message 496 by yxifix, posted 08-17-2004 4:45 AM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 511 of 562 (134647)
08-17-2004 10:42 AM
Reply to: Message 496 by yxifix
08-17-2004 4:45 AM


vxifix writes:
Genetic code can't decide to create an exact mutation it wants and repeat it again and again and again and again.
True, and the theory of evolution agrees with you. Natural selection tends to prune those individuals with unfavorable allele combinations or mutations. The production of allele recombinations and mutations is a game of chance where life just keeps rolling the dice until it wins. Individuals with unfavorable genes lose, but over time the population wins.
A favorable mutation gained by a population was not inserted by an intelligence, but rather was the success story of a lengthy process of blind experimentation. Many random mutations are produced and then tested in the real world by the individuals with the mutations. Some of the mutations are favorable and enhance the individuals probability of survival and reproduction, and over time the favorable mutation will become more and more common within the population. There are simple bacterial genetic experiments that demonstrate these processes in a relatively short period of time.
The only way (according to your words about mutations) is to create a hand by accident by mutations, that means -> By mutations is created 1st part of a hand, then by chance created another and another and another, until by chance half-hand is creted over elbow and then the same process continues until whole hand including fingers and nails is done, maybe in billions stages. ...well, or you can apply it to a "leg" of a fish with legs (part of evolution theory), that's the same in fact... so....you understand what you are talking about?? Absolut nonsense ! Percy. You have to think.
I'm a little uncertain how to reply to this because I couldn't quite get a consistent read on it, but let me take a stab at it anyway.
Evolution does not postulate anything resembling what you describe in the first part of your paragraph. It doesn't think that there were creatures whose arms ended at the wrist and then gradually a hand evolved on the end of the wrist. That there are no handless hominids, apes or monkeys in the fossil record confirms that evolutionary theory is correct on this point.
Evolution believes in the accumulation of many small changes, and this is in line with what I think you're saying in the second part of your paragraph where you mention the fish. The evolutionary progression from fish to amphibians includes fins which gradually became more and more leg-like.
I'm sorry I haven't been provided by your answers. You have to do it again, if you think so. ...the truth is, that to find out which color is '0001' (or A,C,T,G) you need a 'translation' program (RNA)! But this program has to have already 'inserted' information what exactly would new 'mutation' do, if it is "good" mutation!! Otherwise it just won't translate it and a big message "ERROR!" will pop up -> the result? Organism stops working properly.
Your question boils down to this: Once new information has been added to an organism's genome through mutation, how does the cell's machinery know what to do with this new information?
The answer is that it doesn't "know" what to do with it.
Assuming that the mutation takes place in an active gene, that gene codes for the production of a protein. The various alleles of the gene produce slightly different proteins. When a new allele is introduced into this gene through mutation, the new allele will still produce a protein.
There are several possibilities concerning the nature of this protein. It might be identical to the protein produced by one of the other alleles for this gene. Or it might be yet another slightly different type, a new type, of this gene's protein.
If it is a new type of the gene's protein, then what happens is anyone's guess. Maybe the new protein causes the same outcome as one of the other proteins. Maybe it causes something different to happen, perhaps a different eye color. Whatever happens, to the extent the mutation is expressed upon the individual possessing it, that mutation influences that individual's chances of survival and reproduction. If the influence is favorable, then the individual survives, reproduces, and the mutation goes on to become part of the population's gene pool. If the influence is sufficiently unfavorable, the individual does not survive and reproduce, and the mutation dies with the individual.
There is absolutely no chance DNA code can be created without existing cell and a cell can be created without existing DNA. Sorry, but that's the truth.
I think there may be a typo in this. Did you mean "and a cell can't be created..."? Anyway, if I correctly understand what you're getting at here, this seems more an issue of the origin of life than of the origin of species. I don't know where the first DNA or first cell came from, and they weren't issues I was trying to address.
quote:
DNA is a code. It is written in only four 'letters', called A, C, T and G. The meaning of this code lies in the sequence of the letters A, T, C and G in the same way that the meaning of a word lies in the sequence of alphabet letters. Different languages use different alphabets to convey meaning. (Understand this?!!! Intelligence needed! What a shame for your theory, isn't it?)
So what does that mean? To find out which color is 0001, you need and intelligence which can create a program which is able to 'translate' a code '0001'.
As already described above, allele recombination, mutation and natural selection comprise a random trial and error process, and biology students demonstrate this for themselves all the time with simple bacterial mutation experiments. The process happens all by itself without any intelligent intervention at all.
--Percy

This message is a reply to:
 Message 496 by yxifix, posted 08-17-2004 4:45 AM yxifix has replied

Replies to this message:
 Message 516 by yxifix, posted 08-18-2004 11:04 AM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 531 of 562 (134991)
08-18-2004 3:31 PM
Reply to: Message 523 by AdminNosy
08-18-2004 12:21 PM


Re: Pinning him down.
My own opinion is that yxifix is being evasive, abusive and inflammatory. I think these Forum Guidelines are being violated:
  1. Debate in good faith by addressing rebuttals through the introduction of additional evidence or by enlarging upon the argument. Do not merely keep repeating the same points without further elaboration.
  2. Respect for others is the rule here. Argue the position, not the person. The Britannica says, "Usually, in a well-conducted debate, speakers are either emotionally uncommitted or can preserve sufficient detachment to maintain a coolly academic approach."
  3. Make your points by providing supporting evidence and/or argument. Avoid bare assertions. Because it is often not possible to tell which points will prove controversial, it is acceptable to wait until a point is challenged before supporting it.
But I think moderator action might run the risk of making yxifix's volatile behavior just more so. Moderator intervention for his boorish behavior might cause him to abandon the thread, or it could blow up into moderator abuse with ensuing suspension. Resigning ourselves to the long haul while deciding to just endure and ignore the abuse is my own guess as to what will produce the best outcome.
Added by edit: I'm only commenting on yxifix's behavior so far. If his behavior worsens, if, for example, he blows up a la WillowTree, moderator action would make more sense.
--Percy
This message has been edited by Percy, 08-18-2004 02:34 PM

This message is a reply to:
 Message 523 by AdminNosy, posted 08-18-2004 12:21 PM AdminNosy has not replied

Replies to this message:
 Message 532 by mark24, posted 08-18-2004 7:32 PM Percy has not replied
 Message 534 by contracycle, posted 08-19-2004 5:57 AM Percy has not replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 533 of 562 (135122)
08-18-2004 10:22 PM
Reply to: Message 516 by yxifix
08-18-2004 11:04 AM


Hi, Vxifix!
RNA actually plays a different role within the cell than what you've described. The code of life is contained in DNA. RNA is not an alternate copy of DNA, but only a means by which the DNA code is translated into proteins. The cell is a factory for churning out proteins, and the factory works like this.
First, a copy of the DNA code for a gene is constructed of RNA. This is called messenger RNA.
Next, the messenger RNA goes to a construction shop called the ribosome where small building blocks provided by transfer RNA are combined to form proteins.
The process is actually more complex than this, and perhaps some of the biologists here can elaborate if they think it would be helpful or useful, or if my explanation needs some correction since I'm not a biologist. But the important point is that the code for proteins is in the DNA, and it is not mirrored in the RNA. A DNA mutation does not need an equivalent RNA mutation in order to have an effect. Just as a phonograph needle will faithfully trace all the wiggles in the track of a record to produce sound, RNA will faithfully follow the instructions in the DNA code to construct a protein. You don't need a new needle for each new record, and you don't need new RNA for each DNA mutation.
You don't have to read textbooks to understand that this is so, because even genetic engineering articles in the popular press make it clear that it is only necessary to insert the DNA segment in the cell's genome to change cell behavior. Once the new DNA segment is installed, the RNA machinery takes over to produce proteins from the altered DNA.
Once the protein gets out into the organism's body, what happens is anyone's guess. The individual with the mutation plays out its life as best it can. If the mutation is helpful then the individual will probably survive and reproduce, and the new allele caused by the mutation will become part of the population's gene pool. If the mutation is sufficiently harmful, the individual will not survive and reproduce, and the mutation will die with the organism.
Evolution proceeds one small step at a time, each step causing at most an imperceptible change. But over time the changes can accumulate to bring about profound differences.
--Percy

This message is a reply to:
 Message 516 by yxifix, posted 08-18-2004 11:04 AM yxifix has replied

Replies to this message:
 Message 537 by yxifix, posted 08-19-2004 7:05 PM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 545 of 562 (135438)
08-19-2004 9:45 PM
Reply to: Message 537 by yxifix
08-19-2004 7:05 PM


yxifix writes:
But now we are talking about eye color - the problem is that at the same time it has to be an existing eye there otherwise (hypothetic) 'mutations' won't take effect.
The original point I was making was that mutations add information to the genome. The subsidiary point was that mutations can accumulate to cause substantial change. Many Creationists reject the possibility that complex organs like the eye could have arisen by this process, but it's merely the same process we observe taking place in all cell reproduction projected onto a long timeframe.
Another problem is, the code for all stuff can't develop 'naturally' at the same time, a code must be complete
But evolution postulates that change happens in tiny increments, and not all at once in the way you describe here. It is not the scientific view of eye evolution that one day a blind organism spawned a sighted offspring. It is instead postulated that there was a progression from light sensitive skin areas to eye spots to multiple eye spots grouped together to form primitive eyes to covered eyes to concave covered eyes to lensed eyes, each providing a greater survival advantage than what went before. I'm no expert on hypotheses of eye evolution, I'm just trying to give a flavor.
DNA code can't develop itself by accidents.
But that's exactly what it does. Mutations are reproductive accidents. Natural selection filters out the unfavorable ones and keeps the favorable ones. The favorable ones then propagate throughout the population and join the gene pool.
Of course you could say that today's eye was not that complex before but it really doesn't matter.... the same applies to 'fish fin->small leg' example or just imagine lungs... there is absolutely no way a fish could create 'something' that is needed to breath 'outside'. And these are just examples... as you can see all parts needed to stay alive on the air must be generated at the same time.
Evolutionary theory holds that all change is gradual. All the requirements for surviving on air did not need to be available all at once, because the transition from fish to amphibian to land animal was very gradual. One hypothesis for the emergence from the sea is that it occurred in very shallow pools that tended to evaporate, and hence the ability to be able to extract at least some oxygen from the air provided a survival advantage. There are other hypotheses, of course. There may be one involving lung fish, for example.
--Percy

This message is a reply to:
 Message 537 by yxifix, posted 08-19-2004 7:05 PM yxifix has replied

Replies to this message:
 Message 546 by yxifix, posted 08-23-2004 6:11 AM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 550 of 562 (137306)
08-27-2004 5:56 AM
Reply to: Message 546 by yxifix
08-23-2004 6:11 AM


yxifix writes:
How? How can they accumulate? How were evolved wings? How mutations accumulated? Where is your "the fittest survive"? Not complete wings are not an advantage -> they are fatal disadvantage, Percy.
Bird and bat wings are just adaptations from front forelimbs. Their wings have all the same major bones and basic structure as forelimbs. To suggest an example, gradual changes could add some gliding capability, like the flying squirrel with the extra skin between it's forelegs and body. If gliding provides a survival advantage, then flying squirrels with allele combinations or mutations that make gliding easier or more effective will survive to spread their genes throughout the population.
As I think I've already said a couple times, it isn't likely that we'll ever precisely decipher the evolutionary path for things like flight and eyes. While evolution *does* leave clues, there isn't really much of a paper trail. All we can do is take the clues we have and attempt to project backwards using the mechanisms known today, namely natural selection, mutation and allele recombination.
Eyes couldn't evolve from a light sensitive cell on the skin. They have to be connected to brain.
If we're talking about a creature with a brain, then the skin is already connected to the brain by nerve cells. Any mutation causing some skin cells to be more light sensitive would send signals to the brain when light strikes them. The light would probably be interpreted by the brain as heat or touch contact, depending upon which nerve cells connected to the skin respond, but natural selection would favor those individuals whose brain made the most of the information, and the interpretation of the light signals would improve in the population over time.
--Percy

This message is a reply to:
 Message 546 by yxifix, posted 08-23-2004 6:11 AM yxifix has not replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 552 of 562 (138496)
08-31-2004 1:54 PM
Reply to: Message 546 by yxifix
08-23-2004 6:11 AM


Bump for vxifix
You have replies.
--Percy

This message is a reply to:
 Message 546 by yxifix, posted 08-23-2004 6:11 AM yxifix has replied

Replies to this message:
 Message 553 by yxifix, posted 08-31-2004 4:12 PM Percy has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 555 of 562 (138565)
08-31-2004 5:16 PM
Reply to: Message 553 by yxifix
08-31-2004 4:12 PM


Re: Bump for yxifix
yxifix writes:
Hi, sorry, I don't have much time lately for discussions, so my answer is late, of course...so quickly:
The intention was not to prod you into a premature and hurried response. Please take all the time you need if this is a busy period for you. I'll reset the stage in this message.
Percy writes:
Bird and bat wings are just adaptations from front forelimbs.
Both of us know why you haven't mentioned insect wings, for example.
Despite Jar's classification of this as basic, I'm afraid I'm not able to recall anything about insect wing evolution. Perhaps someone can provide some details about current thinking in this area.
Their wings have all the same major bones and basic structure as forelimbs. To suggest an example, gradual changes could add some gliding capability, like the flying squirrel with the extra skin between it's forelegs and body.
Did it just appear? Or were there some stages when extra skin was developing. Of course there couldn't be any otherwise it would be fatal disadvantage.
I don't believe "extra skin" is provided for by DNA. Midgets are not wallowing in extra skin, and children provided growth hormone to become taller do not find their skin stretched taut. During an organism's developmental period up to adulthood, skin apparently grows to accomodate any growth.
And both of us know why you haven't mentioned how bird wings work, why you haven't mention its feathering.
I didn't mention just birds, I mentioned both birds and bats, and feathers aren't a shared characteristic of birds and bats. Feathers evolved from scales. Some orders of dinosaurs were feathered, and it is thought that birds evolved from them.
There's one point that you don't seem to be picking up on that is very important, so I'll repeat it again in this message. Evolution doen't leave much evidence behind. We can only take the clues we have in the form of fossils and genetic data and using the processes we're familiar with project backward in time what might have occurred. Nailing it down in any definitive way in most cases probably won't be possible. It would be like seeing a bird in a tree and trying to deduce what route it took to get there, and what were the previous 5 branches it had rested on. Clearly there's a definitive answer, but there's probably no evidence available to find that answer. Evolutionary pathways provide the same paucity of evidence.
If we're talking about a creature with a brain, then the skin is already connected to the brain by nerve cells. Any mutation causing some skin cells to be more light sensitive would send signals to the brain when light strikes them. The light would probably be interpreted by the brain as heat or touch contact, depending upon which nerve cells connected to the skin respond, but natural selection would favor those individuals whose brain made the most of the information, and the interpretation of the light signals would improve in the population over time.
This is an evident fantasy I won't comment as you've completely forgotten (ignored?) about a mechanism in brain needed to "decode" signals created by vision I was talking about.
But I didn't ignore it. You even quoted it. More briefly this time, I said the mutated skin cells are already connected to the brain by nerve cells, and that the brain would evolve to interpret the signals properly. Creatures possessing brain characteristics best able to interpret the signals would have the best chance of contributing to the next generation. I did not ignore your question, and if you don't like this answer you'll have to tell me why.
You next responded to Loudmouth:
Loudmouth:
Those two small brown dots on the upper left are eyespots. They are not eyeballs, but patches of photosensitive cells arranged inside of a depression, much like a human retina without the rest of the eye. Planarians are able to sense light and the direction the light is coming from which allows them to respond to light stimulus.
These are very very simple "eyes"... yes, there is retina, no lens, no cornea. (these "eyes" are also mentioned in a website I have already mentioned before)
Loudmouth was responding to this from your previous message, which was your response to me when I described how eyes might have evolved initially from skin cells:
Eyes = 2 small balls...how simple is that, isn't it? Really strange how somebody can believe in such nonsense.
So Loudmouth provided the example of planarium, which has two little eyespots that are not "small balls". The planarian does have a brain, primitive though it is and more a ganglia center than a brain, so I'm not sure what he meant when he said it does it without a brain. But we find examples in the animal kingdom of many stages of evolutionary eye development, and so our surmises are fairly well informed.
--Percy

This message is a reply to:
 Message 553 by yxifix, posted 08-31-2004 4:12 PM yxifix has not replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 558 of 562 (140058)
09-05-2004 11:49 AM
Reply to: Message 556 by DrJones*
08-31-2004 5:32 PM


Re: Bump for yxifix
Your avatar looks strangely similar to New Hampshire's state symbol, the Old Man in the Mountain. After years of attempted preservation, the Old Man collapsed a couple years ago, but here's a picture from its heyday next to your avatar:
   
And now, back to our topic. Yxifix?
--Percy

This message is a reply to:
 Message 556 by DrJones*, posted 08-31-2004 5:32 PM DrJones* has not replied

Replies to this message:
 Message 559 by nator, posted 09-05-2004 11:55 AM Percy has replied

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