Evolution Pros and Cons

[questor]

Galapagos has presented a link to a site that everyone intereted in this subject should read. 29+ Evidences for Macroevolution: the Scientific Case for Common Descent This poses and argues the subjects we should be discussing. A quote from this site:
[quote] I am writing this essay in response to a request from Edward E. Max to comment on his posting The Evolution of Improved Fitness (updated July 12 1999). His essay is an attempt to defend evolutionary theory against attacks by creationists. Although Max scored some points against some alleged creationist arguments, he failed to defend Darwinian evolution against my attack on it in my book Not By Chance. He did not mention my book in his posting, but he referred to my book in his request for my comments. I shall also take this opportunity to clarify some issues in my book about which some readers have written me.
The principle message of evolution is that all life descended with modification from a putative single primitive source. I call this the grand sweep of evolution. The mechanism offered for the process of modification is basically the Darwinian one of a long series of steps of random variation, each followed by natural selection. The variation is generally understood today to be random mutations in the DNA.

That primitive source of life is assumed to be sufficiently simple that it could have arisen from nonliving material by chance. There is no theory today that can account for such an event, but I shall not address that issue here. That is for another place and another time. What is relevant to this discussion is that the requirement that life arose spontaneously sets, at the very least, a stringent upper limit on the complexity and information content of the putative first organism that could reproduce itself, and thus serve as a vehicle from which to launch Darwinian evolution. The issue I address here is the alleged development of all life by the neo-Darwinian process of random mutation and natural selection, starting from a sufficiently simple beginning.

Despite the insistence of evolutionists that evolution is a fact, it is really no more than an improbable story. No one has ever shown that macroevolution can work. Most evolutionists assume that macroevolution is just a long sequence of microevolutionary events, but no one has ever shown it to be so. (Those few evolutionists who hold that macroevolution is really different from microevolution have changed their story several times since they first came out with it, and their mechanism is so fuzzy that I cannot tell what it is. John Maynard Smith seems to be of a similar opinion.)

For the grand process of evolution to work, long sequences of "beneficial" mutations must be possible, each building on the previous one and conferring a selective advantage on the organism. The process must be able to lead not only from one species to another, but to the entire advance of life from a simple beginning to the full complexity of life today. There must be a long series of possible mutations, each of which conferring a selective advantage on the organism so that natural selection can make it take over the population. Moreover, there must be not just one, but a great many such series.

The chain must be continuous in that at each stage a change of a single base pair somewhere in the genome can lead to a more adaptive organism in some environmental context. That is, it should be possible to continue to climb an "adaptive" hill, one base change after another, without getting hung up on a local adaptive maximum. No one has ever shown this to be possible.

Now one might say that if evolution were hung up on a local maximum, a large genetic change like a recombination or a transposition could bring it to another higher peak. Large adaptive changes are, however, highly improbable. They are orders of magnitude less probable than getting an adaptive change with a single nucleotide substitution, which is itself improbable. No one has shown this to be possible either.

Moreover, as I have noted in my book, the large mutations such as recombinations and transpositions are mediated by special enzymes and are executed with precision - not the sort of doings one would expect of events that were supposed to be the products of chance. Evolutionists chose the mechanism of randomness, by the way, because we can't think of any other way beneficial mutations might occur in the absence of a law that might govern them. Genetic rearrangements may not be really random at all. They do not seem to qualify as the random mutations neo-Darwinists can invoke whenever needed to escape from a local adaptive maximum.

Evolutionists can argue, and rightly so, that we have no way of observing long series of mutations, since our observation time is limited to a relatively short interval. Our genetic observations over the past 100 years are more like a snapshot of evolution rather than a representative interval in which we can search for the required long series of changes. But our inability to observe such series cannot be used as a justification for the assumption that the series Darwinian theory requires indeed exist.''

''I agree that there are no definitive examples where a macroevolutionary change (such as the development of cetaceans from terrestrial mammals) has been shown to result from a specific chain of mutations. And I agree with your further comment that "we have no way of observing a long series of mutations." But you go on to say that "our inability to observe such series cannot be used as a justification for the assumption that the series Darwinian theory requires indeed exist." An equally reasonable conclusion, in my view, would be that our inability to observe such series cannot be used as a justification for the assumption that such a series of mutations did NOT occur.''[>quote]

Here are two sides of the continuing argument over evolution. One side believes it happens a certain way, cannot prove it, but believes certain evidence, the other side believes it happens a different and proposes contrary evidence. Sounds pretty much like the argument over creationism. Irreducible complexity must be considered in this argument and if any of you reading this material determine the force or reason or mechanism causing mutations or genetic changes leading to differentiation of species by the biochemistry involved, please let me know.

[Moontanman]

First of all I don't see any contary evidence for a mechanism other than evolution via random mutation, I see statemnts that say random mutations cannot be proved to be the basis of evolution but no counter evidence. Is it too much to ask for more than someone just saying they cannot prove it so it must be wrong? Here is another quote from that site.

Are There Other Scientifically Valid Explanations?
The worldwide scientific research community from over the past 140 years has discovered that no known hypothesis other than universal common descent can account scientifically for the unity, diversity, and patterns of terrestrial life. This hypothesis has been verified and corroborated so extensively that it is currently accepted as fact by the overwhelming majority of professional researchers in the biological and geological sciences (AAAS 1990; NAS 2003; NCSE 2003; Working Group 2001). No alternate explanations compete scientifically with common descent, primarily for four main reasons: (1) so many of the predictions of common descent have been confirmed from independent areas of science, (2) no significant contradictory evidence has yet been found, (3) competing possibilities have been contradicted by enormous amounts of scientific data, and (4) many other explanations are untestable, though they may be trivially consistent with biological data.

When evaluating the scientific evidence provided in the following pages, please consider alternate explanations. Most importantly, for each piece of evidence, critically consider what potential observations, if found, would be incompatible with a given alternate explanation. If none exist, that alternate explanation is not scientific. As explained above, a hypothesis that is simply compatible with certain empirical observations cannot use those observations as supporting scientific evidence.

No other theory or hypothesis is being proposed other than God did it. No way to show God did it but lots of evidence that random mutations driven by environmental pressures accounts for it.

[questor]

Moon, you haven't had nearly enough time to read this website. Go to the section on the arguments proposed by creationists and read them. Most of the ''scientific'' proof offered is qualified by ''it could be that....'' or ''it is possible that...'' Hardly the terms used in science. There are no laws in evolution, no axioms. It is still a theory.
You spoke of irreducible complexity. here is where the research is needed:
Single-Gene Biochemistry

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''A central assumption of molecular biology is that cells work by transcribing DNA into messenger RNA, which is then translated into protein. That's familiar enough and uncontroversial. But gene expression has not been directly observed in real time in a live cell on a single-molecule basis. A new live-cell assay system has now been developed that makes such single-molecule observations possible, and can reveal the working of gene expression in live cells. The assay, tested in Escherichia coli, yeast and mouse embryonic stem cells, shows that protein molecules are produced in bursts. The distribution of molecules in each burst is a measure of gene expression levels, which can be compared under different conditions. This has the potential to take the sensitivity of gene expression profiling well beyond that possible today.''
Single-Gene Biochemistry : Nature

IF we can find the biochemical activation factor for genetic alteration, we may find the basis of life itself. All living things run by biochemical reactions, isn't this where true science starts?

[Moontanman]

Originally Posted by questor

Moon, you haven't had nearly enough time to read this website. Go to the section on the arguments proposed by creationists and read them. Most of the ''scientific'' proof offered is qualified by ''it could be that....'' or ''it is possible that...'' Hardly the terms used in science. There are no laws in evolution, no axioms. It is still a theory.
You spoke of irreducible complexity. here is where the research is needed:
Single-Gene Biochemistry

--------------------------------------------------------------------------------

''A central assumption of molecular biology is that cells work by transcribing DNA into messenger RNA, which is then translated into protein. That's familiar enough and uncontroversial. But gene expression has not been directly observed in real time in a live cell on a single-molecule basis. A new live-cell assay system has now been developed that makes such single-molecule observations possible, and can reveal the working of gene expression in live cells. The assay, tested in Escherichia coli, yeast and mouse embryonic stem cells, shows that protein molecules are produced in bursts. The distribution of molecules in each burst is a measure of gene expression levels, which can be compared under different conditions. This has the potential to take the sensitivity of gene expression profiling well beyond that possible today.''
Single-Gene Biochemistry : Nature

IF we can find the biochemical activation factor for genetic alteration, we may find the basis of life itself. All living things run by biochemical reactions, isn't this where true science starts?

And just how much time should I need to read this website? No one has said that evolution is a fact or all the details have been worked out, it's just the best we have, no other theory can account for the evolution of life on the earth. Do you have a better theory? Do you have any theory? I'm not talking about a hypothesis, any one can have a hypothesis, the crack head down the street can have a hypothesis. Lets hear a better theory, just sitting around picking evolution to pieces because it's not perfect is not science either. If you have a better theory that explains the evolution of life lets hear it, stop whining that evolution is not complete and bring on something better.

[questor]

There is enough information and evidence here for anyone to draw their own conclusions, those that believe will believe, those that question will question. I have said enough.

[Galapagos]

Originally Posted by questor

Galapagos has presented a link to a site that everyone intereted in this subject should read. 29+ Evidences for Macroevolution: the Scientific Case for Common Descent This poses and argues the subjects we should be discussing. A quote from this site:

29+ Evidences for Macroevolution: the Scientific Case for Common Descent

The above page has any line of evidence anyone could choose. Fossil, DNA, molecular, speciation events, take your pick.

Instead of acknowledging that evolution certainly did happen, you instead quote yet another creationist website in response to one aspect of the page, and have ignored all of the other evidence.

You are clearly not looking for answers here and have your mind made up questor.

"You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep seated need to believe."
-- Carl Sagan


Oh, and by the way, irreducible complexity is regarded as junk science/pseudoscience by both the U.S. court system and the scientific community. Again, you would have seen this had you checked wikipedia(an incredibly neutral site) instead of a religious conspiracy theory webpage.
Irreducible complexity - Wikipedia, the free encyclopedia
Irreducible Complexity and Michael Behe on Intelligent Design

[Galapagos]

Originally Posted by Moontanman

No one has said that evolution is a fact or all the details have been worked out, it's just the best we have, no other theory can account for the evolution of life on the earth

Actually more than one of my college level biology textbooks refer to evolution as being both a fact and a theory.
Evolution as theory and fact - Wikipedia, the free encyclopedia
I have also seen many famous evolutionary biologists state this in various media( Neil Shubin, Craig Venter, R Dawkins etc).
The fact that creatures have changed over time is not disputed at all and is regarded as a scientific fact with an incredibly high degree of confidence. THe theory is specifically about how these changes took place.

It is like having a court case where you have a million million pieces of evidence indicating who the murderer was, so much to the point where no one could deny it. ANd as we have seen here, most creationists can only maintain their world-view by repeatedly ignoring or overlooking said evidence.


Edit- Awesome paper by T. Ryan Gregory about evolution as fact and theory:
http://www.springerlink.com/content/.../fulltext.html

Originally Posted by TR Gregory

Concluding Remarks

It has been noted many times that evolution is both a fact and a theory (Gould 1981; Moran 1993; Futuyma 1998; Lenski 2000). It can also be considered in terms of a historical path (Ruse 1997). The fact of evolution, that organisms alive today are related by descent from common ancestors, is fundamental to an understanding of biology. As Dobzhansky (1973) famously stated, “nothing in biology makes sense except in the light of evolution”. Nevertheless, a great deal remains to be determined regarding the mechanisms that have created (and destroyed) biological diversity since the emergence of life on Earth. Put in another way, modern evolutionary biology rests upon an extraordinarily solid foundation supported by multiple pillars of evidence, while its theoretical framework remains under construction. That the edifice of evolutionary theory is not yet complete is no cause for concern. Indeed, this is what makes evolutionary biology such an exciting and dynamic modern science.

[questor]

Galapagos, you seem to have difficulty understanding my words. I have never said evolution has not occurred. I said species variation is obvious. I am saying we don't know the biochemical mechanism that causes the changes and what motivates the change to occur. If you can explain this, have at it, if you can't , let's close the thread. This is getting tedious.

[questor]

A couple of parting quotes from Galapagos link:

10.1007/s12052-007-0001-z

''3 Genetic drift involves changes in the genetic composition of populations due to chance events and is most powerful in small populations. It is also widely recognized that mutations, which are the source of the genetic variation upon which other evolutionary processes depend, is “random” in the sense that mutations occur without regard to their consequences for organisms, although not all are equally likely. Natural selection, on the other hand, is the opposite of random chance. While there are chance elements involved (mutation and genetic drift), it is a deep misconception to equate evolution as a whole to random chance.''

Concluding Remarks
It has been noted many times that evolution is both a fact and a theory (Gould 1981; Moran 1993; Futuyma 1998; Lenski 2000). It can also be considered in terms of a historical path (Ruse 1997). The fact of evolution, that organisms alive today are related by descent from common ancestors, is fundamental to an understanding of biology. As Dobzhansky (1973) famously stated, “nothing in biology makes sense except in the light of evolution”. Nevertheless, a great deal remains to be determined regarding the mechanisms that have created (and destroyed) biological diversity since the emergence of life on Earth. Put in another way, modern evolutionary biology rests upon an extraordinarily solid foundation supported by multiple pillars of evidence, while its theoretical framework remains under construction. That the edifice of evolutionary theory is not yet complete is no cause for concern. Indeed, this is what makes evolutionary biology such an exciting and dynamic modern science.''

''Nevertheless, a great deal remains to be determined regarding the ''mechanisms'' that have created (and destroyed) biological diversity since the emergence of life on Earth.''
These mechanisms are what I am talking about.

[Moontanman]

Originally Posted by questor

A couple of parting quotes from Galapagos link:

10.1007/s12052-007-0001-z

''3 Genetic drift involves changes in the genetic composition of populations due to chance events and is most powerful in small populations. It is also widely recognized that mutations, which are the source of the genetic variation upon which other evolutionary processes depend, is “random” in the sense that mutations occur without regard to their consequences for organisms, although not all are equally likely. Natural selection, on the other hand, is the opposite of random chance. While there are chance elements involved (mutation and genetic drift), it is a deep misconception to equate evolution as a whole to random chance.''

Concluding Remarks
It has been noted many times that evolution is both a fact and a theory (Gould 1981; Moran 1993; Futuyma 1998; Lenski 2000). It can also be considered in terms of a historical path (Ruse 1997). The fact of evolution, that organisms alive today are related by descent from common ancestors, is fundamental to an understanding of biology. As Dobzhansky (1973) famously stated, “nothing in biology makes sense except in the light of evolution”. Nevertheless, a great deal remains to be determined regarding the mechanisms that have created (and destroyed) biological diversity since the emergence of life on Earth. Put in another way, modern evolutionary biology rests upon an extraordinarily solid foundation supported by multiple pillars of evidence, while its theoretical framework remains under construction. That the edifice of evolutionary theory is not yet complete is no cause for concern. Indeed, this is what makes evolutionary biology such an exciting and dynamic modern science.''

''Nevertheless, a great deal remains to be determined regarding the ''mechanisms'' that have created (and destroyed) biological diversity since the emergence of life on Earth.''
These mechanisms are what I am talking about.

None of this points toward ID or creationism nor does it point away from evolution. The theory of evolution like all good theories is revamped as new information comes to light, so far it only gets stronger and stronger. Evolution remains the best and only theory of how life had developed on the Earth. Do you really think you've made a point here Questor?