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Author Topic:   Mutation
Loudmouth
Inactive Member


Message 42 of 171 (98459)
04-07-2004 4:10 PM
Reply to: Message 39 by Milagros
04-07-2004 3:31 PM


quote:
Also DC85 , what do you mean, "most are not Visable...?" Visible to the naked eye? Microscope? Electron Microscope? The reason that confuses me is because mutations "HAVE" to be, somehow, visible otherwise, how would we even know if one occurred? Right?
Most mutations are neutral. Usually, this refers to mutations of the DNA in areas that do not code for a protein or are not involved with expression of a protein (eg, promoter regions). Also, neutral mutations can change the amino acid sequence of a protein but the activity and specificity of the protein is unaffected. Obviously, without sequencing the DNA or amino acid sequence of the protein these mutations would not be apparent. So yes, they are visible, but not visible with respect to the functioning of the organism, either as an increase in fitness or a decrease in fitness.
Here is a question for the fold. If a mutation causes a change in phenotype, but is neutral with respect to fitness, can this also be considered a neutral mutation? I would assume that this type of mutation would be considered neutral, but was wondering what the uber-experts thought.

This message is a reply to:
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Replies to this message:
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Loudmouth
Inactive Member


Message 89 of 171 (100008)
04-14-2004 4:15 PM
Reply to: Message 85 by Milagros
04-14-2004 9:48 AM


quote:
The only itty bitty teeny weenie itsy bitsy problem I see with the stone arch comparison is that it was built by conscience, living, breathing, thinking, humans. (Who so happen to also build the scaffolds) Of course any "conscience" person can build, as we've seen, pretty much anything. But we're talking about an "unconscious" process doing it. Are we not?
You may be missing one part of the analogy. A finished arch, with scaffolding removed, is an irreducibly complex system. Without the scaffolding, it is impossible to build the arch, even with human intelligence. Therefore, I could make the argument that space aliens built the arch since no known human could have made the free standing arch. The weakness in the alien argument, and also Behe's argument, is that I am ignoring the supporting structure that could have been around previous to my visit. Behe also ignores indirect routes of addtion and subtraction when commenting on biological systems. Behe claims that the systems could only have come about in one fell swoop via intelligent design, no different than me saying the arch had to come about in one fell swoop by space aliens. Behe must show that these systems have never undergone any change from what we find today in order to validate his claims. He has never and probably never will look for this evidence.

This message is a reply to:
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Loudmouth
Inactive Member


Message 92 of 171 (100037)
04-14-2004 6:37 PM
Reply to: Message 91 by Milagros
04-14-2004 5:53 PM


quote:
I am incredulous to believe that anyone can win it 3 times in a life time. NOT because I think it's impossible but Because I think it's HIGHLY IMPROBABLE.
You are forgetting one factor, number of chances. If I won a 100 million dollar jackpot and take all of that money and buy tickets, chances are I would win again, given that the odds are 1 in 50 million.
Also, given that 100 million tickets are bought for a lottery with 1 in 50 million chances, it doesn't matter that we KNOW if someone won. It is highly probable given the number of chances and the odds of winning. Observation is not needed, only the probabilities.
quote:
What are the "facts" about mutations that you see which shows that they (beneficial mutations) DID result in todays millions of varied species?
Sorry to jump in on a debate, but this is an open forum. For me, the strongest data is in genetic relationships. From the fossil record we can construct trees that relate to common ancestory. From this fossil record we make the hypothesis that genetic differences will increase in direct relation to the amount of time since the last common ancestor between two species. For example, through the fossil record apes and humans should have more similarity than humans and dogs. This hypothesis actually works. Those differences in genetic sequence are due to mutations, and the longer two species have "been apart" the more differences they will have.

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Loudmouth
Inactive Member


Message 97 of 171 (100068)
04-14-2004 8:08 PM
Reply to: Message 94 by Servus Dei
04-14-2004 7:16 PM


Re: Rocks and the Scaffold
quote:
The main problem with this logic is the assembly of the pieces. What has acted on the stone arch to make it assemble? Natural selection can not account for it, as natural selection can only take away thing. Mutations might have set out the pieces, but it cannot put them together. And time, which most would argue as the thing that assembles it all is flawed because time by itself can't do anything.
Of course each mechanism can not "build the arch" by itself. It is the combination of the mechanisms. Mutation creates the pieces, and natural selection determines which pieces stay and which go. In your post, you forgot that natural selection also keeps the good pieces which is an important point. Natural selection causes the accretion of multiple beneficial mutations as much as it removes the bad mutations. Given time, these mechanisms can create complex structures from the selection of good pieces from the ongoing development of pieces through mutation.
quote:
If it could be shown that evolution and nature and time could account for all the steps in the process of building an arch, then the theory of evolution would be a plausible explanation of the construction. Otherwise, evolution isn't an option.
Please explain how mutation and selection is incapable of explaining the biological structures we see today.
quote:
it seems like I am trying to disprove evolution because I am afraid of that as an option, that isn't true.
More of a rhetorical question, but if you hadn't read the Bible would you still have a problem with evolution? In other words, do you object for scientific reasons or religious reasons? Again, more of a rhetorical question but it still shows how our non-scientific preconceptions can taint our objectivity.
quote:
I just don't think that evolution can logically show the origin of life and the universe as exists today.
You should realize that evolution says nothing about the start of life, only the diversification of life once it was started. Also, evolution has nothing to do with how stars form. You might as well be saying that Darwin talked about the evolution of electronic media. Hey, I think I found another type of evolution to add to Hovind's list.

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 Message 94 by Servus Dei, posted 04-14-2004 7:16 PM Servus Dei has replied

Replies to this message:
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Loudmouth
Inactive Member


Message 114 of 171 (101862)
04-22-2004 2:14 PM
Reply to: Message 110 by Milagros
04-21-2004 12:48 AM


Milagros,
The problem that I see is that you are making subjective judgements from your own personal data set. That is, you are making off the cuff decisions from what you know. You like to call this probability, but in fact it is a personal estimation.
To use your example of a person jumping off of a 10 story building, it is a good estimation that most people will die on or directly after impact. However, there are examples of skydivers surviving a fall from an airplane at 10,000 feet. So how do we get the actual probability of survivors from a fall of 100 feet (10 feet/floor)? As ghastly as it sounds, the best way is to push 10,000 people from a 10 story building and see how many survive. After you collect this data, then you move from an estimate to a probability.
Drug companies follow the same technique when testing new drugs. Their study groups can differ between a few thousand to a few hundred thousand. They measure the number of people who recieve a benefit, no benefit, or side effects from the drug in question. This is then compared to the number of people in the placebo group reporting the same effects. These probabilities are then compared to one another to see if the drug is more effective than placebo without a high occurence of side effects. This same study can't be done by observing a few people, or by anecdotal evidence. You seem to be relying on just this sort of data, a few personal observations and anecdotal evidence.
Thirdly, beneficial mutations have been observed. Perhaps you can show us how beneficial mutations can occur but not enough of them do? Remember that we have only known about DNA for about 50 years, much less genes.
quote:
If you've calculated that 3 billion "beneficial" mutations may have occurred, what's that make the average of "beneficial" mutations occurring per year, decade, century, etc.? Now take that number and see if there is any scientific data that confirms this average. So that if you say every 6 years one "beneficial" mutation occurs, we can test this by seeing if this has been observed anywhere at anytime.
Molecular clocks are still a hot topic within evolutionary biology. The theory is that by taking the average mutation rate of a species you can back calculate to find common ancestory between two species. This has been done with fruit flies with decent success. By using the average mutation rate they were able to corroborate speciation with what fossil evidence there is for fruit fly evolution and speciation. From http://www.pubmed.com:
Mol Biol Evol. 2004 Jan;21(1):36-44. Epub 2003 Aug 29.
Temporal patterns of fruit fly (Drosophila) evolution revealed by mutation clocks.
Tamura K, Subramanian S, Kumar S.
Center for Evolutionary Functional Genomics, Arizona Biodesign Institute, and School of Life Sciences, Arizona State University, USA.
Drosophila melanogaster has been a canonical model organism to study genetics, development, behavior, physiology, evolution, and population genetics for nearly a century. Despite this emphasis and the completion of its nuclear genome sequence, the timing of major speciation events leading to the origin of this fruit fly remain elusive because of the paucity of extensive fossil records and biogeographic data. Use of molecular clocks as an alternative has been fraught with non-clock-like accumulation of nucleotide and amino-acid substitutions. Here we present a novel methodology in which genomic mutation distances are used to overcome these limitations and to make use of all available gene sequence data for constructing a fruit fly molecular time scale. Our analysis of 2977 pairwise sequence comparisons from 176 nuclear genes reveals a long-term fruit fly mutation clock ticking at a rate of 11.1 mutations per kilobase pair per Myr. Genomic mutation clock-based timings of the landmark speciation events leading to the evolution of D. melanogaster show that it shared most recent common ancestry 5.4 MYA with D. simulans, 12.6 MYA with D. erecta+D. orena, 12.8 MYA with D. yakuba+D. teisseri, 35.6 MYA with the takahashii subgroup, 41.3 MYA with the montium subgroup, 44.2 MYA with the ananassae subgroup, 54.9 MYA with the obscura group, 62.2 MYA with the willistoni group, and 62.9 MYA with the subgenus Drosophila. These and other estimates are compatible with those known from limited biogeographic and fossil records. The inferred temporal pattern of fruit fly evolution shows correspondence with the cooling patterns of paleoclimate changes and habitat fragmentation in the Cenozoic.
(emphasis mine).
The important bits are highlighted. By using the measured mutation rate it is possible to corroborate what evidence is in the fossil record. This seems to go against what you are saying, that there is not sufficient mutation to account for what we see in the fossil record. It seems that what you find improbable from a subjective point of view collapses when compared to objective, repeatable observations.

This message is a reply to:
 Message 110 by Milagros, posted 04-21-2004 12:48 AM Milagros has not replied

  
Loudmouth
Inactive Member


Message 126 of 171 (104218)
04-30-2004 2:24 PM
Reply to: Message 122 by Milagros
04-29-2004 11:35 PM


Re: Are we still on?
Milagros,
Here is the problems I see with your argument of "not enough beneficial mutations".
1. Common ancestory between species is well supported by genetic research and by morphological changes. Whether or not evolution was the mechanism that caused speciation is less of a certainty than the fact of common ancestory.
2. The mutation rates measured within organisms is in line with the DNA differences seen between organisms. That is, the rate at which mutations occur in an organism matches up with the span of time since common ancestory. On the previous page (mssg #110 I think) I posted an abstract that evidenced the mutation rate in fruit flies with the changes seen in the fossil record and with extant fruit fly species. The final conlusion is that the mutation rate is sufficient to result in the DNA differences we see between species.
3. Beneficial mutations have been observed, so their affects are not in question. However, you have asserted that the beneficial mutation rate is unknown yet you claim they are rare. You then go even farther and say that they are too rare to result in the diversity between species. These two claims, rare and too improbable, follow the claim that the beneficial rate is not known. This seems to be a logical flaw in your argument. To make your claim, you must show how many beneficial mutations there have been and in what time span, and then compare this to the observed mutation rate.

This message is a reply to:
 Message 122 by Milagros, posted 04-29-2004 11:35 PM Milagros has not replied

  
Loudmouth
Inactive Member


Message 155 of 171 (107169)
05-10-2004 4:01 PM
Reply to: Message 154 by Enchanted
05-10-2004 3:40 PM


Re: Mistakes are common
quote:
Ok... so "difference"... however it is still a random accident.
Which is kept or removed from the population gene pool due to natural selection, a non-random, non-chance process.
quote:
Im still learning! lol
We all are in a constant mode of learning. All we can do is help each other learn more, which is the attitude I try to bring to this forum. Right attitude=more knowledge.
quote:
The knee joint is irreduceable and cannot evolve as it requires four complex parts (Posterior cruciate ligament, Anterior cruciate ligament, Tibia and fuma) to exist simultaniosly and i complex assembly to be able to praform a useful function.
Before we go down the irreducibly complex path, perhaps you should check out the thread entitled Behe's Irreducible Complexity Is Refuted. This thread shows the evolution of an IC system found in the middle ear. This example shows how jawbones of a reptile became the small middle ear bones in mammals. It shows how each step in the evolutionary pathway gives an increase in function. This is what we would expect to see in the evolution of the knee as well.
This message has been edited by Loudmouth, 05-10-2004 03:02 PM

This message is a reply to:
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