It looks like you're using an Ad Blocker.

Please white-list or disable AboveTopSecret.com in your ad-blocking tool.

Thank you.

 

Some features of ATS will be disabled while you continue to use an ad-blocker.

 

Creationist Confusion

page: 7
0
<< 4  5  6    8  9  10 >>

log in

join
share:

posted on Dec, 3 2004 @ 04:20 AM
link   
.
to mattison0922,

I have repeatedly denied being a creationist, and have not mentioned God or genesis, other than to plead ignorance.
For someone who 'claims ignorance' you seem ONLY to object to evolution, but don't object to creationism or those who openly [and with honestly and integrity] support it. In fact you give kudos and pats on the back to them. I think i smell a fraud. Could it be you have a not-so-hidden agenda?

[Evolution] is a theory developed around a particular set of observed facts and speculative reasoning. Because the story agrees with the facts does not make it correct.
You are so troubled with evolutionist's explanation yet offer no other logical reasoned explanation of your own.

It's written with a knowledge of certain observations, in an effort to explain said observations.
Well that is what SCIENCE does, doesn't it? It takes facts and tries to understand and explain how all these facts fit together.

BTW the 'law of large numbers says that if you flip a coin a large enough number of times the proportion of heads to tails will be almost exactly even.'
What it means is over the long run the probabilistic odds of something occuring will be represented in actual outcomes. If something will happen 33% of the time one third of the outcomes will be that outcome.

Maybe it is only me to whom it seems apparent but entities best suited to an ecological niche will survive in greater numbers than those that are not as well adapted. And further they will do so in proportion of their suitability to a given environment.

Sickle-cell anemia is common with populations of humans that live in areas that have mosquitoes and malaria. One copy of the gene confirs resistance to malaria, Two copies causes Sickle cell anemia. If my memory serves there is a 40% chance of passing the gene on to offspring. That means the odds of getting two copies is 0.4^2 = 0.16, one copy is 2 * 0.4 * 0.6 = 0.48, and no copies is 0.6^2 = 0.36. [0.16+0.48+0.36=1=100%] This leaves about half the population with some resistance to malaria, A little over a third with no protection and a little over 1/6th of the population sick with sickle cell anemia.
This also has to be calculated with the infection rate of malaria

baseline surveys showed malaria infection rates in children of 60-90%
.link
If malaria was absolutely fatal the proportion of the population having the gene would be higher, if the fatality of malaria was lower the proportion would be lower.

During epidemics the fatality rate was often as high as 85%
www.question.com...
I believe sickle cell anemia without bone marrow transplants or new drugs is close to 100%.

So with 60% infection rate: 16% die of sickle cell, 48% are protected, and .40*.36=.144 unprotected-uninfected, .60*.36=.216 infected unprotected of those .216*.15=.0324 survive; .48+.144+.0324=.6564 survive or about 2/3rds
With 90% infection rate: 16% die of sickle cell, 48% are protected and .10*.36=.036 unprotected-uninfected, .90*.36=.324 infected unprotected, of those .324*.15=.0486; .48+.036+.0486=.5646 survive or a little over 1/2

In short what the system does to optimize survival is balance the sickle cell deaths against the malaria deaths to optimize survival: 16% die of sickle cell and from 18.36% to 27.54% of malaria deaths. (total 16+18.36=34.36 to 16+27.54= 43.54)

With sickle cell gene 34.36% to 43.54% die
without the sickle cell gene between 51% and 76.5% would die

This is an example of evolution in its crude mindless way optimizing survival.

[edit on 3-12-2004 by slank]




posted on Dec, 3 2004 @ 11:43 AM
link   
To Slank:
Thanks for your post. That wasn’t so bad was it? You’ve got some substantiation here… in a perfect world you’d be citing primary references, demonstrating that you’d actually read and evaluated the scientific merit of the said claims for yourself without someone elses ‘filter.’ But, I suppose that I can’t have it all.

Anyway, thanks for bringing up sickle-cell; it’s truly one of my favorite topics. Not necessarily from an evolutionary standpoint, but from a biochemical standpoint as well. Sickle-cell is truly does stand as monument to adaptation and natural selection. The entire globin oxygen transport system with its cooperative transport mechanism and numerous allosteric effectors is fascinating indeed. I posted this in another thread recently, but did you know that plants, and even yeast and other fungi possess hemoglobin? Remarkable, at least I think, but true nonetheless. But I digress… let’s have it.


I have repeatedly denied being a creationist, and have not mentioned God or genesis, other than to plead ignorance.

For someone who 'claims ignorance' you seem ONLY to object to evolution, but don't object to creationism or those who openly [and with honestly and integrity] support it.

Hmmmm… I must again point out that if you’d read my posts and followed this particular thread you’d have realized that my involvement in this thread is for the purpose of demonstrating that evolution is not a fact, that there is plenty of good scientific evidence that would stand in opposition to this fact. So, it’s only natural that I would object to evolution only. This is how I support my thesis. Furthermore, if and when I see a thread where the creation science people start claiming their science proves Devine creation is a fact, I’ll be there as well. Although, it’s much less likely that there would be any lack of outspoken opposition to that thread.


In fact you give kudos and pats on the back to them. I think i smell a fraud. Could it be you have a not-so-hidden agenda?

Hmmm… It seems to me that the largest amount of praise I’ve given out in this particular thread was to Nygdan for his monumental effort to uphold the fossil record. Of course you’d realize this if you’d read the thread. I did give ‘kudos and pats on the back’ to both saint and schmick, but this was not for their belief in creation. Said praise was given in the context of them pleading for people to be open-minded and because they actually seem to be interested in both sides of the issue, not blindly devoted to some dogmatic belief (saint
, schmick
). Not sure what other ‘kudos’ or ‘pats’ you’re referring to, but would be happy to address on a case-by-case basis.


[Evolution] is a theory developed around a particular set of observed facts and speculative reasoning. Because the story agrees with the facts does not make it correct.


You are so troubled with evolutionist's explanation yet offer no other logical reasoned explanation of your own.

Well, my point was never to offer an alternative explanation. And as I’ve pointed out (in this thread) I don’t have an alternate theory. I don’t see why this is relevant. I don’t need to have my own theory in order which data supports the current theory and which data don’t. So you believe that people should blindly follow whatever the popular theory regarding something is, even if they know it doesn’t make sense in multiple contexts, if they can’t offer an explanation of their own? Perhaps my inability to offer an explanation is my own fault. Perhaps if I’d taken the time to read the Bible I’d be speaking to you as a person who believes in creation. However, I, as I’ve accused so many others of, don’t really want to believe in God. It sort of goes against everything I’ve ever been taught or believed. Maybe my statements about not wanting to read through genealogies, or plow through the language of the KJV is my excuse for not facing that which I don’t want to face. Despite my extreme aversion towards Biblically based spirituality, I don’t let it cloud my judgement re: science. I digress again, but I still don’t see the relevance of pointing out that I don’t have my own theory. So what? Theorhetical science is not my thing. I am at heart, even if not in practice any longer a bench scientist: someone who performs experiments, evaluates data, and attempts to see where it all fits in to the big picture. I don’t need a theory to know what I believe and what I don’t.


It's written with a knowledge of certain observations, in an effort to explain said observations

.Well that is what SCIENCE does, doesn't it? It takes facts and tries to understand and explain how all these facts fit together.

Some science does. Not the science that I do. The science that I’ve done is ask a question: What is the function of gene X? Mutate, manipulate, truncate, or remove this gene and observe the effects. Form a hypothesis, and propose additional experiments to test said hypothesis. Said hypothesis never becomes ‘true’ and is only ‘supported’ or ‘not supported.’ In light of a hypothesis being supported, it may or may not make sense in the big picture. That is the way it goes. I’ve got pages and pages of data that may never get published because they don’t make sense in the big picture, at least not yet. Some data may prove publishable in light of some other new unpublished data.

Some sciences take a fact: A fossil exists, for example and try to build up a story based on that coupled with other assumptions: ‘this sediment was laid down 65 million years ago,’ for example. These are two fundamentally different kinds of science, one is inductive while the other is deductive. One is observable and testable, the other is not. It can never be proven that sediment was laid down 65 million years ago, just like it can never be proven that the universe is 15 billion years old.


BTW the 'law of large numbers says that if you flip a coin a large enough number of times the proportion of heads to tails will be almost exactly even.'

Hmmm… on my side of the Mississippi we call that probability. But I did confirm that the ‘Law of large numbers’ does actually exist, and while I am not a mathematician I think its different then what you’ve described, but this is peripheral to the discussion.

The law of large numbers is absolutely dependent on probability of success. The probability of successfully producing a stereospecific coherent biologically relevant polymer de novo via random chemical reactions is 0.000000000%. Thus, the law of large numbers would argue against random assembly of biologically relevant molecules.


What it means is over the long run the probabilistic odds of something occuring will be represented in actual outcomes. If something will happen 33% of the time one third of the outcomes will be that outcome.

I think you could be confusing probability with reality if the chances of something happening are 33%, it doesn’t mean it will happen that often. The probability of having a male vs. female child is nearly equal… ~50%. My mom has 6 sisters and 1 brother obviously ~50% is not represented in the actual outcomes. Each time you attempt something you’ve the same probability of that happening. It’s not progressive. As your number of trials increases you will approach that average value. However a probability of zero doesn’t grant one much flexibility.


Maybe it is only me to whom it seems apparent but entities best suited to an ecological niche will survive in greater numbers than those that are not as well adapted. And further they will do so in proportion of their suitability to a given environment.

Okay, but this is not evolution. This is natural selection. Natural selection ‘selects’ the individuals best suited to certain conditions from the pool of available resources. This is fundamentally different than the generation of new resources seemingly de novo, as would be required at nearly every branch of ANY phylogenic tree. Natural selection actually, paradoxically, results in a loss of genetic information.

Now on to the good stuff!!!


Sickle-cell anemia is common with populations of humans that live in areas that have mosquitoes and malaria. One copy of the gene confirs resistance to malaria, Two copies causes Sickle cell anemia. If my memory serves there is a 40% chance of passing the gene on to offspring.

Hmmm… your memory doesn’t serve you correctly. Allow me to refresh it. The situation is certainly more complex than you’ve described. In the case of 2 carriers that is one sickle cell and one normal gene in both parents (not affected significantly by sickling) The chances are 25% being affected by sickle cell, 50% carrier, and 25% sickle gene free. In the case of two affected individuals having offspring 100% will be affected. In the case of one affected and one carrier 50% will be affected, and 50% will be carriers.


That means the odds of getting two copies is 0.4^2 = 0.16, one copy is 2 * 0.4 * 0.6 = 0.48, and no copies is 0.6^2 = 0.36. [0.16+0.48+0.36=1=100%]

Wrong.


This leaves about half the population with some resistance to malaria, A little over a third with no protection and a little over 1/6th of the population sick with sickle cell anemia.

This may or may not represent the actual affected members of the population, but the distribution within the population isn’t really relevant.


This also has to be calculated with the infection rate of malaria quote: baseline surveys showed malaria infection rates in children of 60-90%

Malarial infection rates are not really relevant either. No one denies that malaria is likely the selective pressure that allowed sickle-cell genes to persist in the gene pool.


If malaria was absolutely fatal the proportion of the population having the gene would be higher, if the fatality of malaria was lower the proportion would be lower. quote: During epidemics the fatality rate was often as high as 85%www.question.com...

Again I fail to see the relevance of malaria statistics in the context of evolution. As I’ve stated, no one denies that malaria is the selective pressure that allowed this allele to persist. Cystic fibrosis is similar. The reason that gene persists in the population, is because the heterozygous state is thought to lend some resistance to typhoid. This certainly explains why these genes with seemingly negative effects persist in populations.
But this is not evidence of evolution. This is merely an increase or decrease of alleles ALREADY present in a population. This is fundamentally different from the macroevolutionary concepts of addition of new genetic information at various stages in the phylogenic trees.


I believe sickle cell anemia without bone marrow transplants or new drugs is close to 100%.

You really should look this stuff up before you post it. I mean you are correct 100% of people with sickle cell are going to die, but so are 100% of people without. If you want to talk actual statistics, even if they are not relevant to this thread, about 50% of people with sickle-cell anemia live into their fifth decade. With some versions of the disease men have an average life expectancy of about 60, and women about 68 years (See: N Engl J Med. 1994 Jun 9;330(23):1639-44.). Given that sickle-cell occurs predominantly in the African-American population and that the life expectancy of all African-american males and females (in one state) was 63 and 70 years respectively, between 1970 and 2000, this doesn’t seem like a huge increase in mortality to me. But again I don’t believe this relevant to the topic at hand.


So with 60% infection rate: 16% die of sickle cell, 48% are protected, and .40*.36=.144 unprotected-uninfected, .60*.36=.216 infected unprotected of those .216*.15=.0324 survive; .48+.144+.0324=.6564 survive or about 2/3rds
With 90% infection rate: 16% die of sickle cell, 48% are protected and .10*.36=.036 unprotected-uninfected, .90*.36=.324 infected unprotected, of those .324*.15=.0486; .48+.036+.0486=.5646 survive or a little over 1/2

In short what the system does to optimize survival is balance the sickle cell deaths against the malaria deaths to optimize survival: 16% die of sickle cell and from 18.36% to 27.54% of malaria deaths. (total 16+18.36=34.36 to 16+27.54= 43.54)

Again, your calculations wrong, and not relevant to the topic at hand, but your effort is appreciated nonetheless.


This is an example of evolution in its crude mindless way optimizing survival.

Again this an example of natural selection altering the balance of existing alleles within a population.



posted on Dec, 4 2004 @ 12:16 AM
link   

If two parents who are carriers have a child, there is a 1-in-4 chance of their child developing the illness
This sounds to me like all double Hemaglobin S persons get the disease.

The sufferers of the illness usually die early.
'Early' is an imprecise term, but certainly must mean die sooner than would otherwise be expected. Whether that means before puberty or not is not clear.
www.worldofmolecules.com...

[A]nyone who suffers from either sickle cell disease or thalassemia. Premature death is likely . . .


Hemoglobin S is widely distributed; it is found most frequently in tropical Africa, with a gene incidence of up to 40% in some tribes.
tmcr.usuhs.mil...
If you have two carrier parents the ratio of their offspring is 25%, 50%, 25%
If the population as a whole is 40% carriers the ratio is 16%, 48%, 36%
(I'm suprised my memory is better than i thought. Yay! no alzheimers yet)


but the distribution within the population isn’t really relevant.
It is the ONLY relevant thing that explains the mechanisms involved. Too many children die of sickle cell, those less likely to have it survive. Too many children die of malaria those less likely to get it survive. NOTE: this is what happens when an environment has a stable condition. The population is optimized for that environment. Most civilized people looking at it would think it brutal and barbaric to balance one kind of death with another kind of death. Only a mindless mechanism would come up with that kind of natural solution.


You really should look this stuff up before you post it. I mean you are correct 100% of people with sickle cell are going to die, but so are 100% of people without. If you want to talk actual statistics, even if they are not relevant to this thread, about 50% of people with sickle-cell anemia live into their fifth decade. With some versions of the disease men have an average life expectancy of about 60, and women about 68 years (See: N Engl J Med. 1994 Jun 9;330(23):1639-44.)

Your citation of the New England Medical Journal Is working with modern day first world subjects with health care, NOT pre-medical indigenous populations.


In probability theory, several laws of large numbers say that the average of a sequence of random variables with a common distribution converges (in the senses given below) to their common expectation, in the limit as the size of the sequence goes to infinity.
en.wikipedia.org...
I believe this means if you roll a single die enough times the odds of getting a one is 1/6, a two is 1/6, etc.

My mom has 6 sisters and 1 brother obviously ~50% is not represented in the actual outcomes.
7 individuals is not a large sample size, a long way from infinity. The preponderance for 1/2 male and 1/2 female only shows clearly when you look at a large number of births. (After birth males have a higher death rate so there is some imbalance there)
.



posted on Dec, 4 2004 @ 03:18 PM
link   
Thanks for your post, Slank.


Originally posted by slank
If two parents who are carriers have a child, there is a 1-in-4 chance of their child developing the illness

This sounds to me like all double Hemaglobin S persons get the disease.

If by ‘double hemoglobin S persons’ you mean individuals homozygous for the sickle cell allele, then you are correct. However in conjunction with the quote regarding carriers it doesn’t make too much sense. The specific quote you mention deals with carriers, or individuals who are homozygous for the gene.


The sufferers of the illness usually die early.


'Early' is an imprecise term, but certainly must mean die sooner than would otherwise be expected. Whether that means before puberty or not is not clear.

Okay, whether or not the sufferers die early is somewhat irrelevant. It’s not postulated that the homozygous condition is responsible for the propagation of disease. The heterozygous, malaria-resistant condition is responsible for propagation and persistence of this particular allele.


[A]nyone who suffers from either sickle cell disease or thalassemia. Premature death is likely . . .

Okay… so what’s your point. You’re attempting to use sickle cell for the purposes of explaining evolution. Pointing out that having the gene makes one more susceptible to premature death is not the way to do this. Furthermore, I don’t believe that anyone would use thalassemia as an example of evolution; it’s a crippling disease offering NO selective advantage in any context. In addition to this sickle-cell trait is a defect. Niether an increase in complexity or an improvement in function is being selected for. Sickle cell trait lends resistance to malaria only via loss of function. Having more carriers in the population means that there will be more people suffering from this terrible disease


Hemoglobin S is widely distributed; it is found most frequently in tropical Africa, with a gene incidence of up to 40% in some tribes.

tmcr.usuhs.mil...
If you have two carrier parents the ratio of their offspring is 25%, 50%, 25%
If the population as a whole is 40% carriers the ratio is 16%, 48%, 36%
(I'm suprised my memory is better than i thought. Yay! no alzheimers yet)

While you’ve not included your calculations, one can only assume that you are calculations are derived from the Hardy-Weinberg equation. I would assume you are aware that Hardy-Weinberg applies to only non-evolving populations. You are probably also aware that Hardy-Wienberg clearly demonstrates that sexual shuffling of genes doesn’t alter the overall frequency of alleles within a population, only selective pressure does that. In this case malaria, in the third world that is, will cause a continuous increase in the frequency of the allele. So eventually, in a non-equilibrium state, such as that in the third world, the frequency of this allele will increase, raising ALL of the percentages you’ve cited above. So actually, sickle-cell, represents a de-evolution of the genetic code, a loss of functionality. This is an important distinction.


but the distribution within the population isn’t really relevant.

It is the ONLY relevant thing that explains the mechanisms involved. Too many children die of sickle cell, those less likely to have it survive. Too many children die of malaria those less likely to get it survive. NOTE: this is what happens when an environment has a stable condition. The population is optimized for that environment. Most civilized people looking at it would think it brutal and barbaric to balance one kind of death with another kind of death. Only a mindless mechanism would come up with that kind of natural solution.

The frequency of alleles isn’t relevant. As I’ve repeatedly mentioned, no one disputes that malaria is likely the selective pressure that has permitted sickle cell to persist within a population. Certainly malaria is increasing the frequency of that allele in the population… again, I don’t think this is in dispute. What is in dispute is whether or not changing of allele frequency is evidence for macroevolution, which it is not.


You really should look this stuff up before you post it. I mean you are correct 100% of people with sickle cell are going to die, but so are 100% of people without. If you want to talk actual statistics, even if they are not relevant to this thread, about 50% of people with sickle-cell anemia live into their fifth decade. With some versions of the disease men have an average life expectancy of about 60, and women about 68 years (See: N Engl J Med. 1994 Jun 9;330(23):1639-44.)


Your citation of the New England Medical Journal Is working with modern day first world subjects with health care, NOT pre-medical indigenous populations.

Hmmm… that would probably be because the data on pre-medical indigenous populations, due to the pre-medical connotation, is spotty, unreliable, and not so easy to come by. By the way… since there are few treatments for sickle-cell, how are those in the first world better off than those in the third world with respect to this disease? Interestingly enough, the western treatments that have recently been developed for alleviation of symptoms are derived from indigenous remedies, demonstrating that we in this medical society are no better equipped to deal with this disease than in ‘pre-medical’ societies.


In probability theory, several laws of large numbers say that the average of a sequence of random variables with a common distribution converges (in the senses given below) to their common expectation, in the limit as the size of the sequence goes to infinity.

en.wikipedia.org...
I believe this means if you roll a single die enough times the odds of getting a one is 1/6, a two is 1/6, etc.

This is exactly what it means, but this doesn’t matter so much when the chances of assembling stereospecific, biologically relevant polymers are many orders of magnitude less than zero.


My mom has 6 sisters and 1 brother obviously ~50% is not represented in the actual outcomes.

7 individuals is not a large sample size, a long way from infinity. The preponderance for 1/2 male and 1/2 female only shows clearly when you look at a large number of births. (After birth males have a higher death rate so there is some imbalance there).

Certainly I am aware of the necessity of large population sizes. That was posted in response to this statement: “If something will happen 33% of the time one third of the outcomes will be that outcome.” Apparently I misread your initial post. What I thought implicit in your post was that 50% of the time a mother will have a boy and 50% they will have a girl. However, I’ve gone back and read the post, and it seems you’ve qualified it via stating large sample size was necessary. My mistake.

This is peripheral, but in addition to the higher death rate, I do believe that birth statistics are skewed slightly in favor of females. The even numbers were picked for clarity of my point.

In any case, Slank, thanks again for your efforts. I would close this particular post by clarifying that we are in agreement with respect to the mechanism that permits sickle-cell to persist in a population. However we still disagree on the implications of said trait. My contention is that simply altering the frequency or number of existing alleles within a population is not proof of macroevolution. It’s proof of adaptability and natural selection, but not proof of macroevolution. Clearly a defective hemoglobin gene is far from addition of new information into a population, and given the destructive nature of said allele, it hardly represents the increase in either the quality or the quantity of unique genetic information that is required by macroevolution. Sickle-cell, while both fascinating and unfortunate is hardly a good example of macroevolutionary change.



posted on Dec, 5 2004 @ 01:20 AM
link   
Firstly I would inquire [with any] whether or not you believe in evolution or not a species retaining as much genetic diversity gives it more [often unexpected] viability/robustness in response to changing environmental conditions?
Obviously I do, and am curious about others. Mono culture in any species, including crop species worries me a great deal.
Initially researchers probablly thought of sickle cell anemia as absolutely a malady, but on further inquiry realized the truth was deeper and more complicated.

(note: the following is speculation from a non-expert)
At one time radiation was given as a possible source of mutations. This is certainly possible, but It seems to me it would more likely just cause damage. In earlier more primative organisms this may have been possible, This would concur with the slow rate of genetic change and 'evolution' towards the beginning of life.

Alternatively I would look closely at the transcription process for errors/goofs that occassionally happen. For single celled dividing organisms the minor (one amino acid change) if not fatal/crippling would probably be reflected in the new divided cells.
Since the effect of a single amino acid change in a structural protein (if not in a crucial point) probably doesn't make a big difference one way or the other. In a critical enzyme or something it probably could be crucial.

With sexual reproduction since two copies of a gene, even if one parent had passed a fatal gene construct (as long as it was recessive) the other working gene would most likely cover it. Sexual reproduction, by having two copies of each gene may allow for a looser handling of genetic materials and inheiritance.

A likely place to look for creation of original genetic combinations is Meiosis:
In Meiosis, prophase I, the chromatids(single paired strand of duplicated chromosome) exchange chunks of genetic material. I have been unable to get clear whether the chiamata (exchange points) ever happen in the middle of a gene or if there is some sort of modularization that blocks this. If the swap point occurs in mid-gene this seems like an easy way new/altered genes can be introduced.

There are also any number of other things that sometimes occur in prophase I, swapping material from two different chromosomes, inversion of a chunk of DNA, duplications, insertions, deletions and Triploids, Monoploids instead of the standard Diploids (two sets of Chromosomes).

It is estimated that from 10–20% of all human fertilized eggs contain chromosome abnormalities, and these are the most common cause of pregnancy failure (35% of the cases)
Interestingly many pretty severe DNA alterations are not fatal. Some do create an essentially sterile adult though.

The amount of genetic variation between the maternal and paternal gene lines in a single individual in the reproductive cells is huge.

Random assortment in humans produces 223 (8,388,608) different combinations of chromosomes. . ., none of these chromosomes is "pure" maternal or paternal. So I think it is safe to conclude that of all the billions of sperm produced by a man during his lifetime (and the hundreds of eggs that mature over the life of a woman), no two have exactly the same gene content.
users.rcn.com...
If this is the case it seems like a point where differences of the maternal genes and paternal genes can be combined into unique combinations. This is one point where creation of unique traits seem likely, over a long period of time.

When geneticists look at human DNA they say 9/10ths of it are 'junk'. What if it is sort of like many people, who store junk in the attic, garage, or basement? Many genes are activated by master control genes. There might be some mechanism that stimulates a master control gene to activate some of these unused chunks of DNA. Also if this 'junk' DNA gets spliced in the middle of an existing gene it would create a new gene combination.

Chemical toxins and Radiation would, I think in most cases just be destructive, and therefore not (very often) create viable mutations. Transcription and Meiosis errors seem, especially with duplicate copies of each chromosome, to have a higher (still low though) probability to seamlessly introduce new viable genetic variations.
.



posted on Dec, 5 2004 @ 03:11 AM
link   
.
further thoughts about sickle cell anemia.

I thought about the 40% carriers ratio.
My math was wrong. There is only a 50% of getting the gene from a carrier. So in the population overall the probability of getting the gene is 20% if 40% are carriers.
So it becomes 4% have sickle cell (die), 32% are protected and 64% have no protection.

During an Epidemic: 4% die, 32% live, 54.4% die, 9.6% live
The next generation would be 77% carriers

Not during an Epidemic: 4% die, 32% live, 64% live
The next generation would be 33% carriers

I would speculate that epidemics are periodic. So the number of carriers would go up and down with Epidemics.
In a weird way paired chromosomes sort of works like having an alternative card to play. With variability in a sexually reproduced population it allows for different genetic strategies to be held in reserve.

With constant epidemics after a few generations one would approach 100% carriers. (But non-carriers would always be present in the next generation)
If epidemics stopped the number of carriers would drop, but I think it would be a very long time before the trait was completely gone.

Would migrating animals tend to be more adaption oriented?

I was wondering if with more than one pair of a gene eccentric proportions of of a trait might be expressed. If it were a completely recessive trait with two genes from each parent it would show only 1/16th of the time. If it showed when 3 out of 4 copies of the recessive gene were present that would be 5/16ths of the time.

digressing . . .

The image that still comes to my mind is fluid, like a water balloon. In freefall a water balloon becomes mostly spherical, when [non-puncturingly] manipulated it can conform to any number of shapes. I see it as a thing rolling/flowing downhill into the future. When something to one side gets in the way it flows off to the other side. Only when blocked broadly flat or cupped does it stop its progress. Maybe a lava lamp also works where sometimes the mass cleaves into a new species or sub-species.

Odd thought: Perhaps (intermitant?) stresses keeps the gene pool flexing and changing, which keeps more variant strains of DNA code active/numerous making for a species ready to adapt. Sort of like, use it or lose it for genetic code. So if a species occupies many environments yet still migrates to interbreed (maintain species cohesiveness) it attains a richer genetic code.

I've often thought the best minds/nervous systems are those that are stimulated, including negative stimulation. Sometimes that can even be mildly torturous, but in a constructive manner. [I may get flamed for being so bluntly honest] In our culture we always want to make everything 'easy' for children, but many of the most outstanding people come from troubled childhoods. I don't want to say people should make children's lives unnecessarily miserable, but we should probably instill certain standards upon them. Within reason I think this is almost arbitrary what they are in particular. Hopefully not ownerous, but certainly offspring should know the world does not revolve soley around them. This also demands of people that they determine what their core values are first. 'To them much is given, from them much is expected' makes a good balance. They will of course find their own ways to shine. They should have a sense that the Universe operates in balance.
.



posted on Dec, 5 2004 @ 04:14 PM
link   
Slank, thanks for your post. Allow me to preface this post by apologizing to you for stating that one of your posts was ‘a monument to ineptitude.’ While the quality of your posts has increased substantially since I did that, I’ve never been much of an ‘the ends justifies the means,’ type of person. So… sorry for saying that in that post. I appreciate your reponses.


Firstly I would inquire [with any] whether or not you believe in evolution

I definitely believe that certain aspects, facts, observations, and conclusions postulated and/or perpetuated via the theory of evolution are true.


or not a species retaining as much genetic diversity gives it more [often unexpected] viability/robustness in response to changing environmental conditions?

Absolutely, genetic diversity is the hallmark of adaptability, which is why genetic engineering scares me so deeply.


Obviously I do, and am curious about others. Mono culture in any species, including crop species worries me a great deal.

I concur. I am also particularly concerned with the large scale use of genetically engineered crops. I personally do not believe adequate data exists to reasonably estimate their impact on the environment. Notice I did not say I am against genetic engineering.
Initially researchers probablly thought of sickle cell anemia as absolutely a malady, but on further inquiry realized the truth was deeper and more complicated.


(note: the following is speculation from a non-expert)
At one time radiation was given as a possible source of mutations. This is certainly possible, but It seems to me it would more likely just cause damage. In earlier more primative organisms this may have been possible, This would concur with the slow rate of genetic change and 'evolution' towards the beginning of life.

Obviously said radiation would have to mutate germ line cells specifically. And yes you are correct radiation tends to damage DNA, rather than mutate. UV radiation damages via dimerization of adjacent Thymine pairs, mutation results when DNA polymerase tries to replicate unrepaired T-dimers; stronger radiation is capable of flat out breaking strands.


Alternatively I would look closely at the transcription process for errors/goofs that occassionally happen.

Transcription errors will not affect the organism’s progeny. Transcription errors will affect only the organism itself. The place to look is in replication errors, or as you point out below, errors in mitosis/meiosis. The reason one doesn’t need to postulate sources of mutation is because the source is built in… via the intrinsic error rate of DNA polymerases.


For single celled dividing organisms the minor (one amino acid change) if not fatal/crippling would probably be reflected in the new divided cells.
Since the effect of a single amino acid change in a structural protein (if not in a crucial point) probably doesn't make a big difference one way or the other. In a critical enzyme or something it probably could be crucial.

Certainly mutations that are passed on are reflected in the progeny of said organism at the DNA, RNA, and protein levels. In general most mutations, due to the redundancy of the genetic code are likely to be silent… that is in the case of substitutions. Insertion/Deletions result in much more profound effects as the ‘reading frame’ of the genetic code is thrown of; Here is an example: Th equic kbrow nfo xjumpe dove rth elaz ydo g. Insertion/deletions can have devastating effects on any protein. But in general, most mutations are either silent, having no effect, or are negative.


With sexual reproduction since two copies of a gene, even if one parent had passed a fatal gene construct (as long as it was recessive) the other working gene would most likely cover it. Sexual reproduction, by having two copies of each gene may allow for a looser handling of genetic materials and inheiritance.

Sexual reproduction allows for a more diverse distribution and recombination of existing alleles, certainly diploid (two copies of each gene) organisms, possess certain advantages over haploid organisms in certain contexts. However, the diploid state doesn’t guarantee absolute dominant/recessive relationships; there are all sorts of other genetic relationships, co-dominance, incomplete dominance. The situation obviously becomes even more complex with polygenic traits and pleiotropic (one gene affecting multiple traits) effects.


A likely place to look for creation of original genetic combinations is Meiosis:
In Meiosis, prophase I, the chromatids(single paired strand of duplicated chromosome) exchange chunks of genetic material. I have been unable to get clear whether the chiamata (exchange points) ever happen in the middle of a gene or if there is some sort of modularization that blocks this. If the swap point occurs in mid-gene this seems like an easy way new/altered genes can be introduced.

Meiosis results in swapping of homologous genes from homologous chromosomes. The chiasmata occur at very specific locations, and the exchange is pretty-much exclusively ‘one-for-one.’ The swap doesn’t occur mid gene, and even if it did you’d most likely be swapping out homologous domains, creating more allelic diversity, but not new genes.


There are also any number of other things that sometimes occur in prophase I, swapping material from two different chromosomes, inversion of a chunk of DNA, duplications, insertions, deletions and Triploids, Monoploids instead of the standard Diploids (two sets of Chromosomes). quote: It is estimated that from 10–20% of all human fertilized eggs contain chromosome abnormalities, and these are the most common cause of pregnancy failure (35% of the cases)Interestingly many pretty severe DNA alterations are not fatal. Some do create an essentially sterile adult though.

Certainly, errors in such a finely tuned process can and do happen, although less frequently than you’d probably believe. And as you’ve correctly pointed out most errors in cell division are negative. A great example of a meiosis error is Down’s Syndrome, resulting from having extra copies of chromosome 21. Interestingly enough, at least I think, it endows one with extra copies of a beneficial gene, super-oxide dismutase that is responsible for breaking down toxic oxygen radicals that result from cellular biochemistry. The problem is SOD is breaking down oxygen radicals into peroxides, which are also damaging. However the catalase system, being located on a different chromosome is overwhelmed because of the extra SOD, and can’t break down the peroxides fast enough. This results in cellular damage, and the increased aging and shortened life spans associated with Down’s individuals. This just demonstrates the precise balance of enzymes and other factors necessary for cellular existence.


The amount of genetic variation between the maternal and paternal gene lines in a single individual in the reproductive cells is huge.quote: Random assortment in humans produces 223 (8,388,608) different combinations of chromosomes. . ., none of these chromosomes is "pure" maternal or paternal. So I think it is safe to conclude that of all the billions of sperm produced by a man during his lifetime (and the hundreds of eggs that mature over the life of a woman), no two have exactly the same gene

Untrue and a bad assumption. I am assuming you mean 2^23 chromosomes. Actually this figure underestimates the different combinations due to recombinations, etc. BUT This doesn’t mean that there are not exact copies of the same genes between parents. You absolutely posses exact copies of some of your parents genes. Fertilization doesn’t mix genes up and pull out new versions. You definitely possess genes that are the EXACT same sequence as your parents. This is what makes things like paternity testing possible.


If this is the case it seems like a point where differences of the maternal genes and paternal genes can be combined into unique combinations. This is one point where creation of unique traits seem likely, over a long period of time.

Again, you are talking about unique combinations of existing alleles, not creation of new genes de novo. You are altering alleles for existing genes, the genes still retain their function. If they don’t it results in death or disesase.


When geneticists look at human DNA they say 9/10ths of it are 'junk'.

This is not true. 9/10ths of DNA are not junk. DNA has many more functions than just coding information. The structure of chromosomes isn’t possible without this ‘junk DNA.’


What if it is sort of like many people, who store junk in the attic, garage, or basement?

Dawkins is wrong about this. We are not storing useless information. All DNA in the chromosomes has a pupose.


Many genes are activated by master control genes. There might be some mechanism that stimulates a master control gene to activate some of these unused chunks of DNA. Also if this 'junk' DNA gets spliced in the middle of an existing gene it would create a new gene combination.

The problem with this is that what was termed ‘junk DNA’ was originally coined this because the sequence obviously doesn’t encode genetic information. This ‘junk-DNA’ is generally composed of repeated regions of differing lengths. Repeated DNA sequence is not coding, but it is not junk. Cerainly inserting junk-DNA would have a effect on a protein, most likely resulting in a devastating frame shift mutation.


Chemical toxins and Radiation would, I think in most cases just be destructive, and therefore not (very often) create viable mutations. Transcription and Meiosis errors seem, especially with duplicate copies of each chromosome, to have a higher (still low though) probability to seamlessly introduce new viable genetic variations.

Again see all above rebuttals. But don’t look to transcription.
.

I thought about the 40% carriers ratio.
My math was wrong. There is only a 50% of getting the gene from a carrier. So in the population overall the probability of getting the gene is 20% if 40% are carriers.

Slank your initial post stating 16, 48, and 36%’s was actually correct assuming an allele frequency of 40%. It’s just that Hardy-Weinberg really only shows whether populations are undergoing natural selection or not. The equation is p^2 * 2pq * q^2, where p and q are the frequencies of the dominant and recessive alleles, respectively. Actually, which is p and which is q, obviously doesn’t matter.


So it becomes 4% have sickle cell (die), 32% are protected and 64% have no protection.

During an Epidemic: 4% die, 32% live, 54.4% die, 9.6% live
The next generation would be 77% carriers

Not during an Epidemic: 4% die, 32% live, 64% live
The next generation would be 33% carriers

I would speculate that epidemics are periodic. So the number of carriers would go up and down with Epidemics.
In a weird way paired chromosomes sort of works like having an alternative card to play. With variability in a sexually reproduced population it allows for different genetic strategies to be held in reserve.

With constant epidemics after a few generations one would approach 100% carriers. (But non-carriers would always be present in the next generation)
If epidemics stopped the number of carriers would drop, but I think it would be a very long time before the trait was completely gone.

Again, I am not sure how relevant this is, as you and I are in complete agreement about what the selective pressure that permitted the allele to propagate in the gene pool is.


Would migrating animals tend to be more adaption oriented?

Good question, and I don’t know. I suppose it depends on what you mean by migration… forced migration vs. natural migration, but this is really not my area of expertise.


I was wondering if with more than one pair of a gene eccentric proportions of of a trait might be expressed. If it were a completely recessive trait with two genes from each parent it would show only 1/16th of the time. If it showed when 3 out of 4 copies of the recessive gene were present that would be 5/16ths of the time.

Not sure I understand this question. Please clarify.


The image that still comes to my mind is fluid, like a water balloon. In freefall a water balloon becomes mostly spherical, when [non-puncturingly] manipulated it can conform to any number of shapes. I see it as a thing rolling/flowing downhill into the future. When something to one side gets in the way it flows off to the other side. Only when blocked broadly flat or cupped does it stop its progress. Maybe a lava lamp also works where sometimes the mass cleaves into a new species or sub-species.

The divergent patterns of development with respect to different traits is probably the analogy you are going for. And I don’t disagree, Darwin’s Galapagos finches probably did see beak morphology change as a result of something resembling his postulate. This, is not really at issue… We are talking about the source of information for the beak coming from the primordial cellular ancestor. This is really where the theory loses me: The constant addition of new and more complex genetic information.


Odd thought: Perhaps (intermitant?) stresses keeps the gene pool flexing and changing, which keeps more variant strains of DNA code active/numerous making for a species ready to adapt.

Not really all that odd. Stress, or selective pressure, IS what selects for particular alleles. However, generally, the selective process weeds out certain less well adapted alleles. So in many ways, natural selection is not responsible for keeping the gene pool diverse, it often limits it.


Sort of like, use it or lose it for genetic code. So if a species occupies many environments yet still migrates to interbreed (maintain species cohesiveness) it attains a richer genetic code.

For the most part the Lamarckian ideas of ‘if you don’t lose something it will disappear’ have pretty much disappeared themselves: and that’s good. However it’s highly unlikely that we are carting around much of anything useless (please no Appendix arguments anyone, at least search for it before posting).


I've often thought the best minds/nervous systems are those that are stimulated, including negative stimulation. Sometimes that can even be mildly torturous, but in a constructive manner. [I may get flamed for being so bluntly honest] In our culture we always want to make everything 'easy' for children, but many of the most outstanding people come from troubled childhoods. I don't want to say people should make children's lives unnecessarily miserable, but we should probably instill certain standards upon them. Within reason I think this is almost arbitrary what they are in particular. Hopefully not ownerous, but certainly offspring should know the world does not revolve soley around them. This also demands of people that they determine what their core values are first. 'To them much is given, from them much is expected' makes a good balance. They will of course find their own ways to shine. They should have a sense that the Universe operates in balance.

Agreed… more or less. Stress is good for an organism.
.



posted on Dec, 6 2004 @ 05:30 AM
link   
.
When I was talking about 'use it or lose it' I meant the species as a whole. (Not Lamarkian)
Without occasional malaria the sickle cell might at some point disappear from the genepool. So I guess I mean all potentially beneficial genes should be utilized by some portion of the species to keep those genes active as an adaptive trait.

It seems to me that the scrambling and re-pasting of genetic material together is 'designed' to create genetic variation. I am not sure if something like this happens in non-sexually reproducing species. But this was probably a big step in accellerating change in genetic code.

Have you heard of the 'Red Queen Theory'? Running/changing as fast as you can just to stay in place. Pathogenic organisms/viruses are constantly changing and the only way potential target organisms can keep up is to adapt and change rapidly too.
We do have immune systems, but this isn't sufficient defense against many organisms. It works often as a 'second time around' defense system.

I find it hard to believe there are not occasional transcription errors. In clone reproduction organisms this would pass the variation on.

I also am inclined to think there are any number of errors that happen during Prophase one of Mieosis.

I have heard speculations that viruses have introduced variation of the genetic code. If these spred to or are in the reproductive cells these variations would be spread to offspring. We are very aware of severly injurious viruses like the flu, but it seems quite possible that there are a lot of more benign viruses, that because they are not injuriously apparent are not hunted for and therefore not noticed. It could be that many chunks of what we call our (human) DNA is actually some ancient virus that has been incorporated into our DNA.

sidenote: I believe the mechanisms for splicing genes may have come originally from observing certain viruses.

Side note: It has been speculated that the mitocondria is actually an organism that combined with a nuclear cell.
Perhaps the nucleous was originally a cell within a cell.

I can see where one might think that the virtual sameness between individuals in a species might imply that there isn't much to work with for creating original genes. But chimpanzees are only 2% different from ourselves.
Note: I use the term 'junk' DNA because i don't know what the proper term for it is. Junk is not necessarily useless, but often just out-dated. But much in the manner that junk people collect is sometimes put to use, this genetic material is available for use as new genetic combinations.

If certain chemicals are present they stimulate cells in the developing embryo to be whatever organ/tissue they are being called on to be. It could be with all this un-utilized (junk) gene code that if the right chemical stimulation were present many other traits/structures might be expessed. Further it might be we are the particular organisms we are not just because of the particular genetic code we have but also because of which genetic code is expessed. Not sure how the master control genes work. If they create the chemicals that stimulate some particular set of genes to activate (and/or shut some off).

It could be that if you stimulate the right set of genes (perhaps using anachronistic control genes) we would come out as some pre-cursor ancestor creature. Like our ancestor that we share with the chimpanzees. The idea of music and chords comes to mind. A master control gene is like pressing a key on an organ that plays an entire chord. We are a set of harmonies that are played with our genetic code, but all the harmonies for many of our ancestors may infact be intact within us. Keys just waiting idle unplayed.

It brings to mind the sick examples of a dropsila fly with fully formed leg growing out of its head and other oddities. They show that the code for any of our organs/structures/tissues is in any cell. I speculate that they may be vastly more than that. With the activation of the right set of idle master control genes we would be some other creature. This might be synthesized with using the chemicals created by some idle master control gene.

We may have many creatures within us.
.



posted on Dec, 6 2004 @ 05:39 AM
link   
.
Often what passes for new technology is just the re-combination/re-use of old things/ideas. This seems very likely the case with genetic code. The wings of birds were on their ancestors, forelimbs. The flippers of Dophins and many marine mammals are from the limbs of ancestors. I think the feelers of many organisms are thought to be adapted limbs.
.



posted on Dec, 6 2004 @ 05:54 AM
link   
New fake leads left by God found... the ice core drilling in the artic has found more (fake) evidence to suggest the Earth is older than 6000 years.
That alongside all the fake dinsaur bones means god is a great forger and has a good sense of humor?

Naaah.. it means these gullible creationist muppets have it very wrong... veeeery wrong indeed.



posted on Dec, 6 2004 @ 06:42 AM
link   

Originally posted by Corinthas
New fake leads left by God found...


Why would the God of truth make fake things to deceive man? This makes no sense.


Originally posted by Corinthas
the ice core drilling in the artic has found more (fake) evidence to suggest the Earth is older than 6000 years.
That alongside all the fake dinsaur bones means god is a great forger and has a good sense of humor?


I believe he has a sense of humor, but only the wicked would think a forgery is funny.


Originally posted by Corinthas
Naaah.. it means these gullible creationist muppets have it very wrong... veeeery wrong indeed.


Yay! I'm a muppet! I loved that show. o/~ "It's time to get things started, it's time to start the show..." o/~. Great, what other titles have you got for me? I'm a Creationist currently because I hate the idea of people thinking evolution is a viable science. Prove me wrong and I'll gladly be an evolutionist. I don't care really, it changes nothing about God. Pardon me if I'm being a Fraggle.


[edit on 6-12-2004 by saint4God]



posted on Dec, 6 2004 @ 11:18 AM
link   

When I was talking about 'use it or lose it' I meant the species as a whole. (Not Lamarkian)
Without occasional malaria the sickle cell might at some point disappear from the genepool. So I guess I mean all potentially beneficial genes should be utilized by some portion of the species to keep those genes active as an adaptive trait.

Thanks for your clarification. I don’t think we are at odds at this issue.


It seems to me that the scrambling and re-pasting of genetic material together is 'designed' to create genetic variation. I am not sure if something like this happens in non-sexually reproducing species. But this was probably a big step in accellerating change in genetic code.

Interesting use of the term designed given the context of this thread. Again, this is not in dispute. I think it should be quite clear from my previous posts that synapsis and crossing over (not with John Edwards) IS a way of creating genetic variation. You’ve missed the point though. This merely reshuffles EXISTING genes. It doesn’t create new ones. No one suggests that reshuffling a deck of cards somehow generates a new package.


Have you heard of the 'Red Queen Theory'? Running/changing as fast as you can just to stay in place. Pathogenic organisms/viruses are constantly changing and the only way potential target organisms can keep up is to adapt and change rapidly too.
We do have immune systems, but this isn't sufficient defense against many organisms. It works often as a 'second time around' defense system.

Not sure why you mention this. There is no disagreement here.


I find it hard to believe there are not occasional transcription errors. In clone reproduction organisms this would pass the variation on.

Sorry, but this indicates that you don’t understand genetics, cellular replication, or transcription/translation. I didn’t say there weren’t occasional transcription errors. I said that transcription errors are not passed on to the next generation. This is absolutely true… time to break out that Bio101 text.


I also am inclined to think there are any number of errors that happen during Prophase one of Mieosis.

Again, this was discussed and acknowledged. Errors due occur. As you pointed out, overwhelmingly such errors have a negative consequence. You can believe whatever you wish, but it doesn’t make it true. You can search the literature until you’re blue in the face, and I can almost guarantee you, you will not find any examples of mistakes in meiosis leading to a positive change.


I have heard speculations that viruses have introduced variation of the genetic code. If these spred to or are in the reproductive cells these variations would be spread to offspring. We are very aware of severly injurious viruses like the flu, but it seems quite possible that there are a lot of more benign viruses, that because they are not injuriously apparent are not hunted for and therefore not noticed. It could be that many chunks of what we call our (human) DNA is actually some ancient virus that has been incorporated into our DNA.

This speculation about viruses certainly does exist. And you are correct, for any changes to be observed in higher organisms, germ-line cells must be affected. Viruses can be implicated in swapping of genetic information between certain species. But I must again point out the distinction between existing genes and creation of genes de novo. Viruses can shuffle genetic material around, and again, it doesn’t create new genes. I suppose it’s possible that there could be some sort of ‘exon shuffling’ going on and generation of fusion proteins. However, if we talk about what we can observe: Fusion proteins have a history of distinctly being not beneficial, think: leukemia. Viruses have a history of ranging from innocuous or not necessarily harmful to completely fatal. Again, I would challenge one to search for information regarding the benefits of contracting a particular virus. This notion, that viruses are potential sources for macroevolutionary change, was postulated some time ago. Researchers still haven’t found this example of beneficial viruses, and not for lack of looking.


I believe the mechanisms for splicing genes may have come originally from observing certain viruses.

While I won’t address the veracity of this particular issue here, but even if it were true how is splicing of existing DNA info into the genome of the same or a very similar organism (based on the host range of viruses) evidence for macroevolution? Obviously the genes will still be there. Generally, when homologous recombination occurs, it replaces the existing gene, doesn’t usually duplicate it. Insertion of viral genomes into the genomes of it’s host tends to be very specific. When it’s not, problems tend to develop, again think: cancer.


It has been speculated that the mitocondria is actually an organism that combined with a nuclear cell.
Perhaps the nucleous was originally a cell within a cell.

Its called endosymbiosis. The theory isn’t that the mitochondria combined with a nucleus, rather it’s that a free living bacteria was engulfed by a free living cell, and have since become dependent on each other. Although once again the evidence for this is spotty at best. It is noteworthy that while the mitochondria do possess a genome, it is truncated, and not complete. Certain mitochondrial proteins are encoded in the nucleus. If it ever was a ‘free-living’ organism, it certainly is no longer capable of sustaining itself outside of the cell. I am not sure what the relevance of proposing a ‘nuclear-endosymbiotic’ theory is. I would also point out that you are virtually alone in this speculation. In all fairness, endosymbiotic theory does make efforts to account for the translocation of mitochondrial genes to the nuclear genome. I suggest reading said evidence prior to supporting this (or any) particular theory.


I can see where one might think that the virtual sameness between individuals in a species might imply that there isn't much to work with for creating original genes. But chimpanzees are only 2% different from ourselves.

First of all, given that human genome has just barely been sequenced, and only for a few individuals, and that to my knowledge NO chimp genome is complete, this is not really a good estimation of the homology. Furthermore if you’d actually read these papers, you’d realize that these experiments were performed using genome hybridization experiments and DNA ‘melting’ curves coupled with kinetic analysis. This type of analysis is not good at discriminating between point mutations, insertions/deletions of large repeated regions of sequence, and other important facets of genomes. Let’s talk about what we DO KNOW about human and chimp DNA: Humans have 23 pairs of chromosomes while chimpanzees have 24. Some evolutionists believe that one of the human chromosomes has been formed through the fusion of two small chromosomes. To my knowledge all known chromosome fusions or translocations are overwhelmingly harmful, again, think leukemia.
At the ends of chromosomes a string of repeating DNA sequences called a telomere exists. This telomere prevents chromosomes from shortening through successive rounds of DNA replication. Chimpanzees and other apes have about 23 kilobases of telomeric repeats. Humans have much shorter telomeres, only 10 kilobases long. Humans are unique among all primates in this capacity. The Y chromosome in particular is of a different size and has many markers that do not line up between the human and chimpanzee. Scientists have prepared a human-chimpanzee comparative map of chromosome 21. ‘[L]arge, non-random regions of difference between the two genomes,’ were observed. They found a number of regions that ‘might correspond to insertions that are specific to the human lineage.’ The size of the chimpanzee genome is 10% greater than the size of the human genome, while certainly genome size and complexity are not necessarily related it is an interesting fact. Generally, these types of differences are not included in calculations of percent DNA homology. In what is one of the most extensive studies to my knowledge that compares human and chimp DNA, researchers compared roughly 19.8 million bases. Sounds like a lot, but represents less than 1% of the genome. They calculated a mean identity of 98.77% or 1.23% differences. However, this study only considered substitutions, ignoring insertions and deletions. A study by Britten (Britten, R.J. 2002. Proc. Natl. Acad. Sci. 99:13633-13635 examined the insertion/deletions between humans and chimps. In this study Britten looked at 779 kilobase pairs to carefully examine differences between chimpanzees and humans. It was in agreement with previous studies demonstrating about 1.4% of the bases had been substituted (98.6% similarity). However, in addition to this a much larger number of insertion/deletions were discovered. The large majority of these were 1 to 4 nucleotides in length, although there were some that were > 1000 base pairs long. Interestingly, the insertion/deletions added an additional 3.4 % of unique base pairs.

Previous studies that have focused on substitutions only have missed what is probably the greatest contribution to the genetic differences between chimps and humans. Missing nucleotides from one or the other seem to account for more than twice the number of substituted nucleotides. While the number of substitutions is about ten times higher than the number of insertion/deletions, the absolute number of nucleotides involved in insertion/deletions is greater. These insertion/deletions were reported to be equally represented in the chimp and human sequences. Thus, the insertions or deletions are not occurring in just the chimp or in just the human, which is suggestive of intrinsic differences in the genome rather than a modification of a pre-existing genome.
Furthermore, using percentages conceals an important fact: If 5% of the DNA between humans and chimps is different, this amounts to something like 150 Million DNA base pairs that are different between them, in addition to the things discussed above.

Meanwhile, other studies have demonstrated a remarkable similarity in the nuclear DNA and mtDNA among modern humans. Available DNA sequences from humans are so similar that some scientists conclude there is a ‘recent single origin for modern humans, with general replacement of archaic populations’ (see: Knight, A. et al. 1996. Proc. Natl. Acad. Sci. 93:4360-4364.). Estimates for a date of a ‘most recent common ancestor’ by the evolution camp places the ‘recent single origin’ about 100,000-200,000 years ago. These estimates were based on comparisons with chimps, assuming a chimp-human common ancestor approximately 5 million years ago. Other studies using pedigrees or generational mtDNA comparisons have yielded a much more recent ‘most common recent ancestor,’ and the creationists will love this, even one at ~6,500 years (See: Heyer, E., et al. 2001. Am J Hum Genet 69:1113-1126, Parsons T.J., et al. 1997. Nat. Genet. 15:363-368, and Sigurgardottir, S., et al. Am J Hum Genet 66:1599-1609). Bolded ref. indicates ~6500 year MCRA reference.

The above examples only further demonstrate that the conclusions of scientific investigations can produce different outcomes depending on how the study was performed. Humans and chimps have 95% or >98.5% homologous DNA depending on which nucleotides are included in the analysis and which are not. Modern humans can be shown to have a single recent ancestor



posted on Dec, 6 2004 @ 06:59 PM
link   
Corinthas,
While i don't believe in God i don't discount any possibility. If there is one I would almost be more supprised if he/she/it didn't have some sense of humor. How sad to have great power and NEVER be free to have fun with it.

Wouldn't it be quite a joke if God [or any great powered mind(s)] were playing with us? The question is, which ones of us? It could be funny as heck looking down at the dumb humans trying desperately to figure things out and throwing a monkey wrench in the works just for laughs.

People do similar things with/to ants, geese, etc, [sometimes on other people] playing, experimenting and manipulating them. Children do it quite naturally, adults tend to do so with some intent in mind.

Honestly, who doesn't occasionally get at least a small charge playing with other people's heads (minds). It is also used as a social weapon/tool. It can be a small joke between friends or it can be completely vicious, cruel and usary, as well as many things between the polar ends.
.



posted on Dec, 6 2004 @ 09:17 PM
link   
evolution is scientifically impossible. fossil records severely lack the evidence like Darwin had hoped. enough said here.
sounds obsurd.



posted on Dec, 13 2004 @ 01:12 PM
link   
I apologize, profusely, for the long time it took to type this out. Its inexcusable, I had planned on beign very thorough, but there really is too much here to address in single posts. I've had to eliminate much of it. Also, I was spending some time considering how much the difference between 'facts' and theories and observations that are based in part on theories need to influence the understanding of this. But ultimately I think that a ;common sense' understanding of facts an observations is sufficient.


Originally posted by mattison0922

Phew! Here it is.

I would like to preface this post by again reiterating my intentions here.

My understanding is that you basically feel that macroevolution is seperate from microevolution and i suppose speciation and that, while there is evidence to support it, that evidence isn't iron clad and that it can't be said to be a 'fact'

I am removing a lot, because these are getting unweildy.

As far as archaeopteryx is concerned, i think that enough has been presented on both sides to allow for the points to stand. I'd be glad to discuss more if you want. Hmm, maybe a different thread would be a good way to pickup?



but my point has always been based on the available evidence, we CANNOT argue evolution as being a fact.

here's where something of a problem arises. I'm going to try to make this as unwordy as I can or else I'll probably start rambling.

One is not observing the fact of macroevolution when one looks at archaeopteryx. One hypothesises that archaeopteryx has the intermediate features that it does because of macroevolution.

Now, this does not mean that we are wasting our time when talking about transitionals, because one cannot observe the paleontological scale changes of 'macroevolution', rather one can only have evidence that is consistent with its occurance. -So-, transitionals are evidence of macroevolution having occured, and they tell us what its done and can do, and are relevant to the discussion. Most importantly, no transitionals, (in so far as we can identify them) then no operation of macroevolution in the past, and that in itself means that there would be major problems with the entire idea of evolution.

However, (and I think that this is a good way to reduce the size of these posts) they can be placed aside when talking about the fact of macroevolution and its mechanisms, and one can consider more small scale changes.


For example, chichilid fishes. Now, a fish is still a fish, as is famously said. However, speciation, as in the cesation of gene flow or even its ability to occur between two populations (even by third parties or something) can be said to have occured here. A single parent population has segregated into two distinct populations, and the result has been that they occupy two different 'environments' and have different morphologies between them.



As I have said, I never would have joined this thread if Aeon had not stated that ‘evolution is a fact.’ That kind of dogmatic speech just pushes my buttons.

Yes but, as you have stated, its a fact that populations change over time, your concern is, is it a fact that they change drastically and into other 'kinds' of animals (again tho, I think that 'kinds', while intuitively understandable today, doesn't have real biological relevance)


These references are offered for contextual purposes: What is often promoted is ‘fact’ is something for which there isn’t even a consensus opinion among scientists.

But the consensus is that evolution occurs. None of what you've presented is from scientists who think that it doesn't occur, they don't argue that it occurs, they argue that the particular pathway given, rather than another evolutionary one, occured. Having said that, I do agree that it shows that one can't domatically assert 'birds evolved from dinosaurs, its a fact'. That, most certainly, is deep in the realm of 'hypotheses'. Infact, its so new and there is enough dispute to keep it a 'hypothesis' for now (of course, thats semantics anyway, if a theory is said to be a hypothesis that has stood up to its tests and not been refuted or superseded by a better hypothesis, but whatever)

I haven’t seen you state this here, but are you stating that evolution is a ‘fact?’

I hope that the above illustrates my stance on the subject. I wouldn't seperate evolution into micro/macro/paleoscale or any of that when I would say that 'Evolution is a fact'. I had actually considered this question for a while. After all, what the heck do I care if evolution is a fact or a 'extremely well supported theory' or even a 'moderately well supported theory, and one that hasn't been superseded by any bettter theories yet'? So when I look at it, I am comfortable with the change in allele freq.


Your objection is of course acknowledged. However this quote was offered for historical perspective, particularly when coupled with the quote from Raup. Again these refs. are offered in refutation re: the statement that evolution is a fact.

This of course rams right up against the issue of what evidence for macroevolution should be, and what macroevolution itself is. Raup notes that transitions are rare, considering that gradualistic/anagenic evolution would mean that there should be a large number of intermediate forms. If macroevolution is taken to mean only these very large transitions, then yes, I agree, those very large transitions haven't been observed in nature; but, and this is important, its only not been observed if one is talking about transitions between different 'kinds' of animals. For example, experiments on selection and genetic manipulation in flies have resulted in viable populations of complete freaks, with different numbers of body segements and limbs comming out of their heads. Nature, not recognizing the human distinction between 'kinds' of animals, isn't going to say 'well, this is so radically different that its not a fly and therefore I will prevent it from existing.' I mean, if flies can exist, and I agree that this is different because its something that happened experimentally in a lab, but if flies can exist in populations where the features are so radically different, is there any reason to think that, say, fish with bony limbs can't benefit and change under selective pressure to develop supporting limbs? So in this way, macroevolution is a fact. Change in populations is observed, in the wild. Speciation is observed, in the wild. And, since the fruit fly and other laboratory experiments show that there is no limit to the 'plasticity', why not state its a fact? But I wholeheartedly agree that its not a fact that birds evolved from dinosaurs, or that tetrapods evolved from some particular group of pre-tetrapods, that is all theory.



In many ways, I don’t feel like we are coming from different perspectives. While I understand the context of these particular quotes, it’s nice that you are elaborating for the rest of the post. My continued assertion: stating evolution is a fact is not science, it’s dogma.


Interestingly enough, this [punctuational evolution] is where some of my biggest problems with evolution began. There is no reasonable mechanism postulated for the rapid change suggested by the fossil record.

Well, as you know from the massive amount of trees that have been sacrificed to the 'Punk Eek' debate, this is not somethign that should probably be discussed here in detail.. I would only put forward that the mechanism that causes the punctuational pattern is promoted as Gould and Eldridge as being Mayrs 'peripatric speciation' mode, wherein speciation, instead of happening in large populations over a large area, happens in very small populations that are practically isolated at the periphery of the species range.




places like say The British Museum have impeded this kind of research. Why?



Why should the BM grant more access to archaeopteryx? Wickramasingh's analysis was teribly flawed and the specimins are clearly not frauds. Also, the BM doesn't control all the specimins. Are you suggesting that the most rational answer is that they know its a fraud and are covering it up?
Perhaps you’d care to comment in the flawed methods used by Wickramasingh, especially in light of the flawed analysis of Spetner.

The spetner analysis was only flawed in that it didn't take particular note of there not being the same anomolous substance on the control portion. The thing is, the lack of the substance on the control section of the slab without any fossil material is consistent with the stuff being a preservative that was selectively applied to the fossi surfaces, rather than the entire slab surface. Now, I don't know if there is preservative or anything else in all the areas, but that would be consistent with wickramasingh's analysis. Also, I think that the chemical make-up of the substance being consistent with a preservative is rather suggestive of it being a preservative.



At the end of the three days of presentations, [Alan] Charig [chief curator of fossil amphibians, reptiles, and birds at the British Museum—BH/BT] orchestrated a concerted effort to summarize the ideas for which consensus exists. The general credo runs as follows: Archaeopteryx was a bird that could fly, but it was not necessarily the direct ancestor of modern birds.... A communiqué expressing the unanimous belief of all participants in the evolutionary origin and significance of Archaeopteryx was adopted, in order to forestall possible misuse by creationists of apparent discord among scientists (1985, 5:179).
Personally, I find it interesting and somewhat disheatening that the scientists at the meeting felt constrained to adopt a unanimous resolution concerning the “evolutionary origin and significance of Archaeopteryx” solely to prevent creationists
I think that that is a good thing. Most creationists are anti-rational, anti-scientific, and anti-intellect. Oh, surely, several of them use scientific sounding analyses, and in particular the chemists in the ID movement are using techniques that are very scientific sounding, but ultimately their positions are entirely those of faith, and they are anti-scientific. I mean, if the conclusion that evolution is a fact is dogmatic, then what is it when one looks to the bible as absolute literal truth and tries to conform the evidence to it?










Ahhhh, then you see my point. The point is there are so many different issues with respect to this stuff that to argue it a fact is absurd.

I will have to insist however that the transitionals are not promoted as observations of the fact of evolution, but are rather theorized to be the results of evolution. In that way they can allow people to study evolution. But the fossil record itself isn't 'evidence' of the fact of evolution. However, it would be rather difficult to explain the fossil record if evolution doesn't occur, and in that way its supportive of macroevolution. But, in a way, thats 'overkill'. Macroevolution is said to be a fact because of the laboratory evidence. Really, what one might best look at is darwin and his peers. When darwin came around, he wasn't arguing that evolution occurs, he was arguing that it occurs through natural selection. The genetic, most of the paleontological, and even some of the observational evidence, didn't exist in darwin's time. Yet many naturalists considered that it was a fact that evolution occurs, they could see that populations of organisms aren't static and arent composed of disctinct invariable types.


To prematurely discuss some issues in this post: Gravity is not a controversial theory, (notice I didn’t say fact). The reason is because the effects are consistently observed and measurable.
But gravity particles and gravity waves aren't observed. In a similar sense to evolution, its only thought that the planets and such move because of gravity. Their movement and nature conform to the requirements of gravity and the predictions of gravity theory are generally met. I'll agree that gravity is generally accepted as occuring, but then again people aren't personally offended at the idea of gravity. The anti-evolution position is normally a visceral emotional one, and half the time there isn't even a concern that animals evolved, only offense taken at the idea that man evolved.And of course there are some people who argue that gravity doesn't occur or that its the result of an entirely different phenomenon. Most of those people are generally loons tho. Of course, even in the physical sciences, there are some suggestions and attemps at 'unifying' gravity along with other forces. And also the fact that gravity doesn't work at extremely small distances, and may even work differently at very large distances (but thats a more controversial issue) show that radical changes to the theorys of just what gravity is are possible and infact probable or even, completely necessary. And even just regular old gravity has changed, Newtonian gravity was superseded by Einsteinian gravity. If Gravity in that sense was a fact, then Einstein's advancement wouldn't have been possible, or at least it would be wrong. So the situation is analagous to evolution. Gravity obviously is occuring, and its doubtful that anything coudl demonstrate that it doesn't, while on the other hand there are a variety of theories as to how it works and such and they have been changing eversince a Theory of Gravity was first proposed. This makes the variety of opinions and theories relevant to evolution all the less surprsing, since gravity is a 'fundamental' force of nature, while evolution is suubject to chemical physical and 'biological' 'laws'.



Homologous structures, initially thought to be controlled by descent with modification and natural selection of genes, are continuously being demonstrated to be controlled by DIFFERENT genes at the molecular level.
Such as what? And is it all of them? This aspect might demonstrate that particular homologies aren't homologous, but there are still homologies across the natural world. The hox genes for example, are the usual 'poster boy' of homology.


Clear to who, clear to you? Not clear to every scientists in the field.

its a quasi walking ape showing a trend torwards increasing brain size and human like facial and dental features. What else could a transitional between a man and a chimp look like?
I’m sorry, but similar features does NOT necessarily imply similar ancestry. It’s not an unreasonable assumption, but it’s not a fact.
But it cannot then be stated that these organisms aren't related. The point isn't that the ape-man transition is a factual observation of macroevolution, the fossils aren't breeding and giving birth in front of us in the first place. The point is that these fossisl can't be said to not be intermediates, their features are intermediate between the 'types'. They show that the 'type' doesn't actually exist, because they are inbetween it. Similarly archaeopteryx with its combinations of features, most broadly the hands, tail and head of a reptile with a hallux and feathers, show that, irregardless of what archaeopteryx is, that there isn't a 'bird type'. That all the features of birds are in other animals, espcially the prime features of feathers. The 'type', the kind, is an accident of the history of nature. If whatever the heck archaeopteryx and the other dinobirds and some dinosuars were still around, people probably wouldn't have any concept of a bird type, or at least it woudl be a very different concept, one that included ground running barely feathered no beaked sharp tooth long tailed screaming monsters that rip things apart with their hands.

These would of course argue against the factual nature of evolution, and again point out the speculative, not factual nature of the theory.

I think that the rejection of any 'transition' in the fossil record can't refute evolution, no more than any transition can 'prove' the factual nature of evolution.


. In fact, the DNA sequences for all people are so similar that scientists generally conclude that there is a ‘recent single origin for modern humans, with general replacement of archaic populations.

But this in itself is evolution. They are citing that evolution occured. I understand and agree that it shows that there is some controversy and disagreement on the specific patheways of evolution, but this only is an issue for the theory on the pathway.


To be fair, the estimates for a date of a ‘most recent common ancestor’ (MRCA) by evolutionists has this ‘recent single origin’ about 100,000-200,000 years ago. In contrast, studies that have used pedigrees or generational mtDNA comparisons have yielded a much more recent MRCA—even 6,500 years
! I'll have to check that one out, thats a very strange thing to get. 6,500 years ago was 4,500 BC, practically the historical era. I've read about there having been a populational 'bottleneck', one that is proposed to account for the genuinely surprising closely relatedness of humans and the low variability. I've often heard that the whole modern human population is less variable, in terms of genetics even not just phenotype, than -populations- of chimps. Not all 'chimpkind' as a whole but just subpopulations of groups of chimps. No reference on that, its one of those 'factoids' that just sticks in yer head.





here is ASU's Institute of Human Origns take on it
Did you insert this for a point of personal irony? Just Curious.
? No, i thought that it would make a good 'generalized' statement on it. Why? I think I am missing something.


I am sure that you are aware of ‘convergent evolution’ as Aeon felt it necessary to point out to me.



Also, on convergent evolution, if it were to occur, it'd be an example of macroevolution. So you can't maintain that australpithecines are animals that have converged on the human type, and still say macroevolution doesn't occur. Unless you would say that they were all instantaneously created and the similiarity isn't due to convergence or any other evolutionary phenomenon.
Point taken. I was using the point of convergence to illustrate the fact that different explanations are offered when evidence doesn’t fit the currently accepted scenario. The point was that because things are similar doesn’t prove common ancestry. It may suggest it, but there could be other reasons for the similarity.
Well, phylogenetics and cladistics are more or less based on this similarity idea in combination with parsimony and some other aspects. however, cladistics isn't the fact of evolution. Cladistics is an attempt, based on theoretical considerations, to reconstruct hypothetical phylogenies. Each 'cladistic tree' is a hypothesis in and of itself. THey can, and of course routinely are, be refuted, rejected, and replaced. Homology is very suggestive that evolution occurs, but it is theoretical. IOW evolution explains homology, homology doesn't explain evolution.






Based on observable evidence, such as the rate of natural, unrepaired mutation in an organisms DNA for example

And you are stating that its too slow to lead to a strengthening of the limbs over the general timespan involved? I mean, the move from a perch to a lizard is a big jump, but from a bony limbed shallow water fish to a more boney limbed terrestrial amphibian?

While your point about existing variation is taken, existing variation in genetic structures in unable to account for the appearance of new genetic information,
Perhaps this is the greatest stumbling block then. If the genetic evidence demonstrates that, despite appearances, evolution cannot occur, if it refutes the idea that evolution occurs, then that woudl be significant.




This is not the point. The point is that there is considerable dissention

There is considerable dissention on the transitions, but none of the authors cited argue that evolution doesn't occur. As far as any of them can tell, and say, it does occur. They simply argue that a different set of archosaurs evolved into birds, or that a particualar organism is more terrestrial than usually thought, but the factual occurance of evolution is not based on this weak, theoretical transitions. Indeed, you are quite right, there is dissention and lack of consensus on some of these aspects, but there is a consensus that evolution occurs.


On Kow Swamp man and the differences betwen sapiens and erectus, only slightly features distinguish man from primitive apes in the first place. And I think that the point about the Kow Swamp specimin is that, its not erectus, its sapiens, and this means that erectus has a suite of features that are not found in sapiens. Of course, those features are "quantatative" in a sense, not qualitative. IE erectus has no chin or a smaller braincase, whereas modern man and kow swamp man has a larger braincase and more of a chin, differences in degree, not in kind, which is acceptable under the understanding of the differences between species.


We can’t look at the specimen as a whole without analyzing the individual components of that whole. If parts of the whole don’t add up though, HOW is the whole going to add up?

Perhaps I am being obtuse but I am not entirely sure I understand the comment. erectus, or any organism, doesn't need say one or two characters that are not had in any other organism in order to be considered a distinct species. They can have quantitative differences than other organisms, they can have no characters that are unique in and of themselves, but are merely 'more' or 'less' than others, ie more expanded, less vaulted, more keratinized, more sculptured, etc etc. Look at foxes and wolves. These are differences of degrees. Or even dogs and cats. Extend the snout, alter the musculature, allow the claws to retract, these aren't immpossible changes that would so radically alter the genome that the organism couldn;t function. If a fruit fly can have legs growing in place of antennae or have entire bod y segments lost, or duplicated, then surely these sorts of changes are possible. (agian, I'd hedge that there is a difference between hypothesised changes in the fossil record and deliberate changes in the lab, but it does show that the genome can be altered, that, as complex and interconnected it is, it can be radically altered, and, even in the fruit fly experiements, the changes were brought about by exposing the organisms to radiation and the like, not be selectively designing the freaks).




Nygdan, I’m sorry but this absurd, and doesn’t take evolution as a whole into account. There absolutely are kind barriers.

Ah, this is a strong statement, and probably the one we should try to focus on.


There are multiple very real, very difficult barriers that must be explained for this theory to be a ‘fact.’

The issue that I have with this is that, just what are these 'kind' barriers? For example, one could've said that feathers were a kind barrier, that they are something that had to have been formed ad hoc and at once. But they don't have to be. There are plausible antecedants to flight feathers in the fossil record. Given that, even tho we can't state as fact that "dino-fuzz" evolved into feathers, we can say that there isn't anything barring feathers from evolving. The 'kind barrier' of feathers doesn't exist, because feathers aren't limited to any kind of animal. And the tetrapod limb, similarly, there is nothing 'kind like' about it. Its just a limb with some bones. Its not far fetched to say that it could've come from more primitive antecedents, even if, as in other cases you've brought up, the genetic information has altered radically also. Its not insurmountable change, given that flys can have their entire body plan altered and survive. I understand that it ends up meaning a lot of changing of the genome, but obviously the genome can withstand change. At least thats how I understand it to be.

Now, of course you are not a fan of the Talk Origins newsgroup's archive, but there is a page about this subject.
www.talkorigins.org...
www.talkorigins.org...
www.talkorigins.org...

I note them because they do discuss the issue, and because they have the references relevant to the issue at hand. I, however, haven't been able to read those particualr references. The case made in them is that, infact, new structures can arise from old ones, and that 'arbitrary' gene sequences can result in functional ones.

I think that one of their notes is intersting:

According to Shannon-Weaver information theory, random noise maximizes information.

Its interesting because 'information theory' is often brought up, and it can be a counter-intuitive subject.


I will reiterate the is no proposed reasonable mechanism to account for the formation of new genetic information.

I do not understand. Why are mutations an insufficient source of new variation/information? Mutations are known to occur, they alter the genome, why aren't they able to alter it in such a way that results in a slightly different phenotype? And why can't natural selection act on this to result in new structures? I'll agree that the process isn't entirely understood, I'll agree that this is a theorectical portion of evolution, but the lack of a complete answer as to how evolution operates isn't in itself a refutation of hte concept or something that allows us to say that the factual observations of change in populations don't occur. We see change in populatins within a species. We see the evolution of new species. We see the induced but drastic alteration of the genome. We see evolution occuring, and, insofar as we do see that, we can state that evolution is a fact.


Dawkins for a refutation of this concept.

Which of his books refutes this?



On the out of place skulls, I am generally unfamiliar with the literature on them, so I can't really say anythign more than I already have.




1. “new” species that are “new” to man, but whose “newness” remains equivocal in light of observed genetic “variation” vs. genetic “change” (as discussed above), and/or because a species of unknown age is being observed by man for the first time.

If I understand this correctly you are saying its an issue because, say, in chichilids the new species isn't particularly different than the old right? Its just a different variation on the same type right?


2. “new” species whose appearance was deliberately and artificially brought about by the efforts of intelligent human manipulation, and whose status as new “species” remain unequivocally consequential to laboratory experiments rather than natural processes.

Indeed, human based selection is what inspired, some say, Darwin to come up with natural selection. The agent of selection isn't necesarily whats important here. Afterall, the humans didn't create ad hoc a new gene or set of genes and work out how it could be inserted into the organisms without disturbing their genome to the point of destruction. They selected for traits. Nature, too, can Select for traits. But, this sort of thing is the theory of natural selection, not the fact of evolution. The fact that the populations can be changed so radically is enough to show that evolution occurs. Infact, aren't you arguing that it doesn't occur, not that it occurs at the direction of any intelligence, man or god?



In neither of the above examples cited by Isaak was the natural (i.e., unaided) generation of a new species accomplished or observed, in which an unequivocally “new” trait was obtained (i.e., new genetic information created) and carried forward within a population of organisms.


in 5.9.1of this one of those pages one finds that multicellularity was observed to have occured in a unicellular organism Chlorella vulgaris, and in 5.9.1 Nakajima and Kurihara 1994 observed multicellurlarity in a bacterium, Shikano et al observed a morphological change of a size increase of 13 times the original size, from short rods to long filaments along with a size increase of 13 times. The human element shouldnt be rejected as 'design', since often all they are doing is providing selection pressure, or causing more exposure to radiation and thus an increase in random mutations. If the problem is that a totally new structure hasn't been observed to have evolved in nature de novo, well, thats not exactly what is expected to be the fact of evolution. Bird wings, for example, needn't have evolved out of nothing and all at once. Its the 'progressive' change that is the key to it. The change in a population of finches to have beaks that are stronger and larger than before, and a shift in diet from small plants to large hard shelled nuts has to be evolution. The new variation did not exist before, its new variation and new information. Yes, finches had beaks to begin with, but they didn't have those kind of beaks.


not just variations within a type of organism but the emergence of entirely new organisms.

Well, if its a question of massive change into entirely different sorts of organisms without any human selection, then I agree, this has not been observed. This does not mean macroevolution does not have a factual basis. Organisms speciate, and organisms change. Thats all that is required for macroevolution.


Definitions of “species” and (therefore) “speciation” remain are and varied, and by most modern definitions, certain changes within organism populations do conveniently qualify as “speciation events.” However after many decades of study, there remains no solid evidence that an increase in both quality and quantity of genetic information (as required for a macro-evolutionary speciation event) has happened or could happen.

Entire chromosomes have been seen to have duplicated and freed up for all sorts of selective pressure. And genes and even sets of chromosomes. And variation beyond the ancestral populations range has been observed to occur, this isn't 'hidden' genetic information, this is natural selection eliminating the unfit/promoting the fit and ever present mutation resulting in new random variation about the new mean.



As for Dobzhansky’s fruit fly experiments, it should be pointed out that an example of a laboratory-induced physiological change in a specimen, even if it involves genetic change, can hardly be considered proof that NATURAL evolution occurs, since the change did not take place without the deliberate activity of man.

But that deliberate change is often nothing more than providing a selective pressure, or in some cases merely exposing them to more radiation. Heck in one they only provided a maze with two alternate routes and rewards in them. There's no reason to think that this invalidates the changes, anymore than setting up a chemical reaction implies that it doesn't happen in nature.


Furthermore, a genetic, mutational change alone, while it may qualify as microevolution, does not demonstrate evolution per se: Evolution does not require just change, but progressive change,
On this I would have to disagree. Evolution is merely change, progressive or non-progressive. From the human viewpoint, and from a current temporal viewpoint, it certainly often looks like things have been progressive. But, for example, Eohippus wasn't under pressure to become the modern horse. It was under various pressures at variuos times and different populations of it evolved in all sorts of directions. Progression is not required. In particular it shouldn't have anythin to do with the appearance of a new trait.
In Dobzhansky’s work, numerous varieties resulted from radiation bombardment: fruit flies with extra wings, fruit flies with no wings, fruit flies with huge wings, fruit flies with tiny wings. In the end the only thing produced was fruit flies! Dobzhansky meddled with the genetic code


But he didn't directly and specifically alter it. He, in a sense, caused possibly hundreds of years of random, no directed mutations to occur over a few generations. And the result was entirely new body plans. If mere mutations can produce that, then what is supposed to prevent them from causing anything else? And these organisms needn't be more fit, becuase there was no selective pressure. Think about it, without selective pressure, all those changes occured. What would happen if there was selection and time for it to act on the organism?





Even the bird to dinosaur transition almost starts to fall 'below the level of kinds' of animals and into the 'microevolutionary' change level.


BS. Dinosaur to bird transitions have never been classified as microevolution. Please point out a reference where this is referred to this way.


The change from somethign like herrerasaurus to modern pigeons is of course huge, and I am not claiming that, if one accepts the existence of 'kinds' (which I do not accept as a biological term) is 'inter-kind' change. What I am saying is that the change from things like archaeopteryx to birds, or microraptor and other very bird like dinosaurs shows that the 'morphological gap' between birds and dinosaurs is extremely small. Birds, again, have extremely few features that dinosaurs don't. How can one seriously contend that more co-ossification of vertrebrae is huge and fanatastic 'inter-kind' change? Or more reduction of the tail bones, or more fusion of the hand bones? Kinds simply do not exist in biology.
I would again encourage you to consider the big picture and the amount of genetic information to be added to go from E. Coli like organisms to homo sapien like organisms…. Really, seriously ponder that for a while, and I encourage you to try and answer it for yourself.

With over 4 billion years of time and a nearly infinite number of generations? Selective pressure in small 'microevolutionary' steps can produce practically any 'macroevolutionary' patter. Induce multicellularity, cause differentiation of cells, let entirely different organisms meld into the same one, throw in new genetic information with viruses, increase some of the different types of cells and decrease the others. All the changes involved, they are mind boggling in terms of 'raw' evolution, in terms of raw factual uncontroversial and seemingly powerless changes in a population. But with direction, with natural selection, they become workable. With speciation they become accelerated and with limits to plasticity they become 'progressive'.


.




I was sold on evolution until the subject of the primordial cell came up, then I started seriously researching it.

Well, at least if there is anyway to reject modern biology, that would be it. Its the great unknown in it all.





Gravity seems to hold up very well at all levels except the quantum level.

As before, which gravity? Newtons, einsteins? Tommrrows?

[qujote] Similarly, you can mix two organic reagents together and get coherent repeatable results time after time.
And you can seperate populations and apply selection and get speciation.

[quiote]However the result of evolution is merely inferred, and never observed (macro).
The only thing that is not observed are the paleontological scale changes, which are not the 'factual' observation of evolution.


This is the essence of my argument, notice how I didn’t say gravity is a ‘fact.’

Well, I think that most people would say that gravity is a fact, and that, after all, the initial problem was that most people were saying 'evolution is a fact' when it isn't. I'd say that evolution is as much a fact as gravity. And, similarly, that macro-evolution has as much to do with micro-evoltion as gravity at, say, the scale of feet and inches has to do with gravity as the scale of AU or galaxies.

But, if we want to talk about which theories are better supported, ie Einsteins theories on gravity and Darwin's theories that natural selection occurs, well, that would be a different sort of thing that talking about it being a fact.


If you want to reject "macroevolution" because you've never witnessed it, then you'd also have to reject almost any chemical reaction, or the existence of transitional states within those reactions that are too small to see or too ephemeral to be 'observed' in the same manner than you want to observe macroevolution.
Please see my above rebuttal. While reactions can’t be observed, their results can be measured with some degree of reproducibility. Furthermore transition states can be studied; there are entire fields of study devoted to this,
Yes, but, interestingl, a transition state in a chemical reaction doesn't necessarilly exist. Similarly, one can draw the structure of a series of resonance structures of an organic molecule, but one realizes that this 'thing' is just a construct of theory, and that the actual thing doesn't truly conform to any of those structures. Nonetheless, one can predict the products of reactions with it and list the properties of the 'resonance chemical'. That doesn't mean that, merely because the true nature of the transition isn't understood, that the reaction isn't occuring.



one of the major one’s is drug development. I specifically did a major portion of my graduate work re: enzyme thermodynamics and transition state analogs.

Christ. And you still find time to read a forum about reptiloid illuminati pyramid builders from planet x eh?



posted on Dec, 13 2004 @ 01:42 PM
link   
Nygdan,
Thanks for replying. I genuinely had lost faith in your response. Anyway... it will take me some time to respond to this particular post. I have read it, not thoroughly, but I see there's some good info there.

It's funny, because we agree on many different levels... I have never asserted that populations don't change over time, certainly they do. Certainly, I am intimately aware of the fundamental nature of DNA to change and for the frequencies of alleles within a population to change, and for the ability of new alleles to appear as a result of mutation and susequently persist because of natural selection. These are not the fundamental issues that stand between us.

I will address your post... hopefully before the weekend... maybe not though... I may take some liberties and sum up a few of your ideas into a single rebuttal, as there are some themes within your post. We shall see. Anyway, looking forward to responding, and again thanks for your reply.



posted on Dec, 13 2004 @ 03:46 PM
link   

Originally posted by mattison0922
Nygdan,
Thanks for replying. I genuinely had lost faith in your response.

Yeah I'm really sorry about that I took far too long to get to this.



posted on Dec, 13 2004 @ 10:48 PM
link   
.
My impression [correct if wrong], mattison0922 is that you see and acknowlege microevolution as is observable, but since there is no smoking gun macro evolution you feel free to challenge macro [new-gene production] evolution. [In true science everything is open to scrutiny, It is always the search for truth and not the supposition of truth]

Q: do you take exception to any/all dating methodologies?

My take. Since the nature of evolution [macro or micro] is to adapt to an environment and because I believe much of the time environments change very suddenly [ie. flash frozen mamoths] the transitional forms are probably going to be rather more scarce. Compound this with the fact that stable forms that are believed to have existed for 10s of millions of years are very scarce themselves.

Through time it seems that many forms have existed [many more than now exist] and they seem be progressively more elaborated from a similar/general base form. It seems all dinosaurs were reptiles. But grandually changed/diversified over the 100s of millions of years they 'dominated'.

Now anything may be possible, but barring divine intervention the best logical explanation, it seems to me is that all the various forms seen in fossils are stemming to and from one another. At one time flies were thought to spontaneously come from rotting meat. And other organisms likewise. I assume we all agree that this does not happen? The fact we all know is a species line is generated from it's own offspring. Since this is the [a] line of heritage of which we are aware, it becomes the only one we can point to as a possible explanation.

I am certainly open to hearing some other explanation that accounts for the fossil record as it is. I just don't have one off the top of my head. [Aliens intermitently playing with genetic material, mostly spoofing, but you never know]

There might be some kind of stress factor that pulls idle genes into action, but that is extremely speculative.

Certain stress conditions might create enzymes that break DNA into short chunks for recombination. This under stress conditions creates many mutated forms, mostlly unsuccessful, but increases the odds of a new beneficial mutation. Randomly trying to create a useful mutation would be favored by a high population and high reproductive rate.

It could be there may be some radical behavior that causes/creates new forms to occur. [Another wild idea] Maybe instead of creating new genes from scratch there is some way that genes are taken whole from other species and somehow concatenated with the 'evolving' species DNA. This would mean that the gene had some intrinsic [if possibly irrelevant] logic to it. Certainly the probability for usefulness is far better than simple random mutation of protiens. [Would that mean evolution was a 'thief'?]

Maybe after several [one?] generations of malnutrition it stimulates a need for new forms. Which has a sort of logic to it. A well fed species in biological rationale has no need to change. A species that is struggling needs to change. Maybe we should examine a species that is struggling to survive without actually being wiped out. Interestingly enough nutritionally balanced caloric deprivation up to a point creates a longer life-span in mammals. This would allow an individual to create more offspring which would allow for a higer number of mutated offspring without endangering the species.

People do seem to procreate more, subsequent to some kind of violent disaster.

I am grasping for explanations, but anytime one is trying to reverse engineer some unknown process one can only guess at what happens inside the 'black box'.
.



posted on Dec, 14 2004 @ 10:33 PM
link   
Slank,

Nice to see you back.

Nygdan… hang in there, itsacomin.



My impression [correct if wrong], mattison0922 is that you see and acknowlege microevolution as is observable, but since there is no smoking gun macro evolution you feel free to challenge macro [new-gene production] evolution. [In true science everything is open to scrutiny, It is always the search for truth and not the supposition of truth]

I see and acknowledge that the allele frequencies existing in a population change in response to natural selection. I have real difficulties with the not the evolution of new genetic information per se, but in the nature of the way it seems to brought about. Glycolysis for example, has like 10 steps, and doesn’t actually yield any energy until the end of the pathway… furthermore, the pathway requires the end products (ATP) for it to commence. This is a real chicken-and-egg conundrum in my opinion.


Q: do you take exception to any/all dating methodologies?

I take serious exception to all RADIOMETRIC dating methods.


Now anything may be possible, but barring divine intervention the best logical explanation,
Devine intervention will never be proven. However, claiming evolution is a fact would tend to halt progress. If something’s a fact, what challenge is there to said theory.


I am certainly open to hearing some other explanation that accounts for the fossil record as it is. I just don't have one off the top of my head. [Aliens intermitently playing with genetic material, mostly spoofing, but you never know]

Liquefaction and sorting (observed phenomena) during a large scale catastrophe such as an earthquake or a flood can account for this particularly intriguing observation.



There might be some kind of stress factor that pulls idle genes into action, but that is extremely speculative.

There might be. A simple mutation could, theorhetically, reactivate dormant genes. We just need to find evidence of this.


Certain stress conditions might create enzymes that break DNA into short chunks for recombination. This under stress conditions creates many mutated forms, mostlly unsuccessful, but increases the odds of a new beneficial mutation. Randomly trying to create a useful mutation would be favored by a high population and high reproductive rate.

The odds of a beneficial mutation are always the same. Creation of many mutated forms increases the number of mutations and hence increases your odds. This is the way that a virus like HIV adapts… luck of the draw… maybe the law of large numbers as you called it.



It could be there may be some radical behavior that causes/creates new forms to occur. [Another wild idea] Maybe instead of creating new genes from scratch there is some way that genes are taken whole from other species and somehow concatenated with the 'evolving' species DNA. This would mean that the gene had some intrinsic [if possibly irrelevant] logic to it. Certainly the probability for usefulness is far better than simple random mutation of protiens. [Would that mean evolution was a 'thief'?]

Maybe after several [one?] generations of malnutrition it stimulates a need for new forms. Which has a sort of logic to it. A well fed species in biological rationale has no need to change. A species that is struggling needs to change. Maybe we should examine a species that is struggling to survive without actually being wiped out. Interestingly enough nutritionally balanced caloric deprivation up to a point creates a longer life-span in mammals. This would allow an individual to create more offspring which would allow for a higer number of mutated offspring without endangering the species.


This is sort of along the lines of the SINGLE good example of something that arguably is evidence for evolution of new genetic information. That would be the appearance of enzymes that are capable of breaking down nylon in microorganisms. This is, IMO, the ONLY known example of what seems to spontaneous appearance of a completely new genetic trait. This is a serious point of contention among the evolution/creation debate.



posted on Dec, 23 2004 @ 12:07 AM
link   
.
Very interesting newly identified genetic mechanism of bacteria transfers gene 'cassettes' both intra species and inter species.

This sounds a bit like object oriented programming with computers.
It is the technique of modularization.

As I read it cassettes of DNA [a gene?] can be traded between individuals within a species and across species. Many can be stored and if positioned in an activation point will be expressed.

This indicates that nature already has been discovered doing some of its own gene splicing, even between species.

The discovery was made on work with all of the antibiotic resitant strains of bacteria now appearing.
link

Where I first noticed this was the current story on 'superbugs' being found commonly in turkey.
.



new topics

top topics



 
0
<< 4  5  6    8  9  10 >>

log in

join