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Biological Evolution: What Is Being Debated


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#1 John Paul

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Posted 08 June 2005 - 06:14 AM

"The major tenets of the evolutionary synthesis, then, were that populations contain genetic variation that arises by random (ie. not adaptively directed) mutation and recombination; that populations evolve by changes in gene frequency brought about by random genetic drift, gene flow, and especially natural selection; that most adaptive genetic variants have individually slight phenotypic effects so that phenotypic changes are gradual (although some alleles with discrete effects may be advantageous, as in certain color polymorphisms); that diversification comes about by speciation, which normally entails the gradual evolution of reproductive isolation among populations; and that these processes, continued for sufficiently long, give rise to changes of such great magnitude as to warrant the designation of higher taxonomic levels (genera, families, and so forth)."
- Futuyma, D.J. in Evolutionary Biology, Sinauer Associates, 1986; p.12
from talk origins: (on the above)
This description would be incomprehensible to Darwin since he was unaware of genes and genetic drift. The modern theory of the mechanism of evolution differs from Darwinism in three important respects:
1. It recognizes several mechanisms of evolution in addition to natural selection. One of these, random genetic drift, may be as important as natural selection.
2. It recognizes that characteristics are inherited as discrete entities called genes. Variation within a population is due to the presence of multiple alleles of a gene.
3. It postulates that speciation is (usually) due to the gradual accumulation of small genetic changes. This is equivalent to saying that macroevolution is simply a lot of microevolution.
In other words, the Modern Synthesis is a theory about how evolution works at the level of genes, phenotypes, and populations whereas Darwinism was concerned mainly with organisms, speciation and individuals. This is a major paradigm shift and those who fail to appreciate it find themselves out of step with the thinking of evolutionary biologists. Many instances of such confusion can be seen here in the newsgroups, in the popular press, and in the writings of anti-evolutionists.


From the book jacket of The Blind Watchmaker:

Natural selection, the unconscious, automatic, blind yet essentially non-random process that Darwin discovered, has no purpose in mind. If it can be said to play the role of watchmaker in nature, it is the blind watchmaker.



(from Darwinism, Design and Public Education

1925- Scopes: Maynard M. Metcalf (zoologist)- 1st expert witness for the defense “Evolution and the theories of evolution are fundamentally different things. The fact of evolution is a thing that is perfectly and absolutely clear, but there are many points- theoretical points as to the methods by which evolution has been brought about- that we are not yet in possession of scientific knowledge to answer.”

Fast forward to 1982- Yale biologist Keith Stewart Thompson breaks evolution down a little further- into 3 meanings: change over time, common ancestry and the natural mechanisms that produce change in organisms.

Jump to 2003 and it gets broken down even further.
The meanings of evolution, from Darwinism, Design and Public Education:

1. Change over time; history of nature; any sequence of events in nature
2. Changes in the frequencies of alleles in the gene pool of a population
3. Limited common descent: the idea that particular groups of organisms have descended from a common ancestor.
4. The mechanisms responsible for the change required to produce limited descent with modification, chiefly natural selection acting on random variations or mutations.
5. Universal common descent: the idea that all organisms have descended from a single common ancestor.
6. “Blind watchmaker” thesis: the idea that all organisms have descended from common ancestors solely through an unguided, unintelligent, purposeless, material processes such as natural selection acting on random variations or mutations; that the mechanisms of natural selection, random variation and mutation, and perhaps other similarly naturalistic mechanisms, are completely sufficient to account for the appearance of design in living organisms.

With the above in mind it has become obvious to me that IDists and anti-IDists (blind-watchmaker proponents) differ on four major points. These are as follows:
(in no necessary order of importance)

1) The starting point of the evolutionary process.

2) The phenotypic & morphological plasticity allowed/ extent the evolutionary process can take a population (do limits exist?).

3) The apparent direction the evolutionary process took to form the history of life. Is it possible to increase genetic, phenotypic and morphological complexity on the scale required?

4) The mechanism for the evolutionary process. Is the genetic code really akin to a computer code? Can a “blind-watchmaker” thesis really hold water with what we do know about life’s complexity, the laws of nature, the requirements for life and the requirements for complex life?


For example the starting point of the evolutionary process- Creationists say it was from the originally Created Kinds. What were those Kinds? That is what we need science for. If we knew the answers science wouldn’t be necessary.

The same can be said of evolutionists and their search for LUCA (Last Universal Common Ancestor). Was it one population, one organism or multiple populations?
IDists would also like to know life’s origins and will accept what the evidence leads to. If it leads to we are the ancestors

The starting point is important in that if life did not arise from non-living matter via unintelligent, blind/ undirected processes, there would be no reason to infer its subsequent diversity is the result of those processes.

Point 2 above deals with limits. Creationists say there are limits, a boundary that can’t be passed. Possible boundaries would be between prokaryotes and eukaryotes; single-celled and metazoans; shell and no-shell; vertebrates and invertebrates. IDists

Evolutionists say no such boundaries exist but can only get around the alleged barriers via assertion. IOW they throw vasts amounts of time at the issue.

We know limits exist in life & to life itself. Why should the evolutionary process be exempt? Evolutionists want Creationist to point to a boundary. Some say it has been done. Genetic homeostasis is the term used for the resistance a population has towards change. That term came about because what has been observed in the lab, and in the real world, is that although allele frequencies do change, the overall body plan remains the same.

Point 3 above will be clarified here. I am not saying the theory of evolution says anything about a direction. I am saying that the way evolutionists are applying the theory to come up with a history of life (on Earth) implies that life started out much simpler and then evolved to be more complex. Creationists say that the originally created kinds had more genetic information than the extant fauna & flora.

The mechanism- Random mutations culled by natural selection, environmentally induced mutations, organism induced mutations, some pre-programmed plan, lateral transfer, culled by any selection process.

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Posted 08 June 2005 - 09:12 AM

This assertion should be easy to prove. Show us a "kind" and show us where the imagined "barrier" is.

If you can show that the kind can evolve no further than that, you've made your point.

Tell us about it.

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Posted 08 June 2005 - 09:38 AM

In other words, the Modern Synthesis is a theory about how evolution works at the level of genes, phenotypes, and populations whereas Darwinism was concerned mainly with organisms, speciation and individuals.

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Many of Darwin's observations have withstood the test of time, despite the fact that he made them without the benefit of the knowledge provided by Mendel (let alone Watson and Crick). I imagine that he would have been a most enthusiastic pupil of genetics and molecular biology, and would have welcomed the opportunity to see his ideas tested using the mathematical rigor made possible by these new insights. But I think it is overstating things to suggest that the Modern Synthesis consists entirely of such mathematical analyses. There is still plenty of room for theoretical proposals of the sort Darwin was so good at coming up with, and for various approaches to interpreting the data we see emerging out of the mathematical models -- in fact, the mathematical models often produce new questions as quickly as they do new answers. What is debated within the scientific community (such as the importance of drift, or the nuances of pleiotropy) bears little resemblance to what is debated between IDists and anti-IDists (such as how to define 'information', or what is meant by 'kinds').

#4 John Paul

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Posted 08 June 2005 - 01:09 PM

Yehren:
This assertion should be easy to prove.


Science is not about proving.

Yehren:
Show us a "kind" and show us where the imagined "barrier" is.


I covered that in my opening post. Did you read it?

Yehren:
If you can show that the kind can evolve no further than that, you've made your point.


I have been waiting for over 40 years for evolutionists to show that the alleged "great transformations" (see the PBS series Evolution) could be accounted for via some mutation/ selection process.

Yehren:
Tell us about it.


It all started with the claim that all of life's diversity owed its collective commom ancstry to some unknown populations that just happened to have the ability to self-replicate. Not only is this premise beyond observation & experimentation, it also goes against the evidence we do observe and experiment on.

#5 chance

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Posted 08 June 2005 - 02:36 PM

John Paul why is

Evolutionists say no such boundaries exist but can only get around the alleged barriers via assertion. IOW they throw vasts amounts of time at the issue.

‘time’ not a valid point?

#6 John Paul

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Posted 08 June 2005 - 03:07 PM

John Paul why is  ‘time’ not a valid point?

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Can it be tested & reproduced? If yes then it is valid. If used as a "hocus-pocus" then it isn't valid. IOW looking at variations within a population and adding time is not scientifically valid when discussing the alleged evolution of cetaceans from land animals.

But anyway this link may help:

Extrapolating From Small Changes

#7 chance

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Posted 08 June 2005 - 07:13 PM

Can it be tested & reproduced? If yes then it is valid. If used as a "hocus-pocus" then it isn't valid. IOW looking at variations within a population and adding time is not  scientifically valid when discussing the alleged evolution of cetaceans from land animals.

But anyway this link may help:

Extrapolating From Small Changes

View Post


There are many separate and independent methods of testing for age, so yes that can be tested.

With fast reproducing species some changes can be observed.

The fossil record show vast amounts of changes through the life of the earth.

However to answer some points from the link

Consider a biological example. Jones begins to lift weights and starts by bench pressing 100 pounds. After one week, he'd up to 110 pounds. After 2 weeks, he's pressing 120 pounds. He then uses formula (1) and predicts that after 2 years of working out, he'd be benching pressing 1140 pounds. Of course, we also know from experience, that the constraints of anatomy and physiology step in and will prevent Jones from ever bench pressing so much weight.

Let's say that you decide to create a pile of coins at a rate of one coin added/day. After one week, you'll have a pile seven coins high. From this small scale perspective, you then argue that after 10 years of adding coins, you'll have a pile 3,650 coins high. But we all know, from experience, that the laws of physics will eventually step in as the tower of coins becomes unstable at some point and comes crashing to the ground


The above ‘poor’ analogies only highlight a limit to the speed evolution can work not the impossibility of it.

Structural differences. Imagine we invent a new machine called the "Expander." The Expander works as follows: material that is placed inside the Expander is magnified in size, i.e., it expands to becomes many times larger than the original. Now, if we cut off a small piece of the Sun or a small piece from a mountain, and place it in the Expander, we could essentially generate a new sun or mountain. This is because both the Sun and mountains can be viewed as "aggregates," where a mass of parts are loosely associated with each other in an unorganized fashion. But if we were to take a chunk of skin from a mouse and put it in the Expander, we would not generate a new mouse. This is because a mouse is not truly an aggregate, but instead of composed of many different parts that are tightly organized. While it seems perfectly reasonable to view aggregates in terms of (1), given that expansion/enlargement lend themselves nicely to such process, it is not clear at all that biotic organization follows suit.


Another distorted analogy, what if we take the ‘DNA’ and expand it then yes, you would get a new mouse.

Formational differences. Middle ear bones and avian lungs form as the result of a genetic program which, in turn, is run by encoded instructions deciphered by nanomachines. Stars and mountains are not built by nanomachines or encoded instructions. Thus, when we consider that both the structural complexity and the formation of stars/mountains differ significantly from that of living organisms, acceptance of (1) in the former cases does not automatically entail we accept it in the later case.

rather obvious I would think. I feel the author is confusing complexity with size.

First, it is well-known that small genetic changes over small periods of time can lead to large morphological changes. Unfortunately, most of the observed examples of such change are clearly deleterious. Yet a significant number of biologists throughout the years have proposed such "macromutations" to explain various evolutionary transitions

bold my emphasis, and that’s all it takes, as long as there is a beneficial trait that is passed on, that’s evolution. Micro/macro is a smokescreen.

But what does this mean? It would mean that all of the fossil evidence is largely the consequence of trivial evolutionary events that have little meaning for the origin of much cellular machinery. 


Partially agree with this, e.g. all mammals, reptiles, birds are basically all quadrupeds, we all have to breath oxygen, reseparate, so in a very real way there has been little change since the Devonian period (if you get my meaning) to me this show the common ancestry nature of living things. You could look at it like this, evolution changes a basic plan that does not change much.

Attempts to justify this move by appealing to the use of (1) in astronomy and geology fail because biotic complexity differs in both structure and formation.


I still don’t get this part of the authors objection to evolution, but suspect it is to try to find an problem where non exists.

#8 John Paul

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Posted 09 June 2005 - 05:30 AM

QUOTE(John Paul @ Jun 9 2005, 08:07 AM)
Can it be tested & reproduced? If yes then it is valid. If used as a "hocus-pocus" then it isn't valid. IOW looking at variations within a population and adding time is not scientifically valid when discussing the alleged evolution of cetaceans from land animals.

But anyway this link may help:

Extrapolating From Small Changes


chance:
There are many separate and independent methods of testing for age, so yes that can be tested.


That is not what I was talking about.

chance:
With fast reproducing species some changes can be observed

Read the OP again. Changes, per se, are not being debated.

chance:
The fossil record show vast amounts of changes through the life of the earth.


The fossil record can't tell us anything about a mechanism. IOW we don't know how the organisms that are represented in the fossil record came to be.

chance:
However to answer some points from the link

QUOTE
Consider a biological example. Jones begins to lift weights and starts by bench pressing 100 pounds. After one week, he'd up to 110 pounds. After 2 weeks, he's pressing 120 pounds. He then uses formula (1) and predicts that after 2 years of working out, he'd be benching pressing 1140 pounds. Of course, we also know from experience, that the constraints of anatomy and physiology step in and will prevent Jones from ever bench pressing so much weight.

Let's say that you decide to create a pile of coins at a rate of one coin added/day. After one week, you'll have a pile seven coins high. From this small scale perspective, you then argue that after 10 years of adding coins, you'll have a pile 3,650 coins high. But we all know, from experience, that the laws of physics will eventually step in as the tower of coins becomes unstable at some point and comes crashing to the ground



The above ‘poor’ analogies only highlight a limit to the speed evolution can work not the impossibility of it.


The analogies are only 'poor' to you because they go against your way of thinking. Also if you read the OP evolution isn't being debated. Allele frequencies do change.


QUOTE
Structural differences. Imagine we invent a new machine called the "Expander." The Expander works as follows: material that is placed inside the Expander is magnified in size, i.e., it expands to becomes many times larger than the original. Now, if we cut off a small piece of the Sun or a small piece from a mountain, and place it in the Expander, we could essentially generate a new sun or mountain. This is because both the Sun and mountains can be viewed as "aggregates," where a mass of parts are loosely associated with each other in an unorganized fashion. But if we were to take a chunk of skin from a mouse and put it in the Expander, we would not generate a new mouse. This is because a mouse is not truly an aggregate, but instead of composed of many different parts that are tightly organized. While it seems perfectly reasonable to view aggregates in terms of (1), given that expansion/enlargement lend themselves nicely to such process, it is not clear at all that biotic organization follows suit.

chance:
Another distorted analogy, what if we take the ‘DNA’ and expand it then yes, you would get a new mouse.


No we would not. Life is more than DNA.


QUOTE
Formational differences. Middle ear bones and avian lungs form as the result of a genetic program which, in turn, is run by encoded instructions deciphered by nanomachines. Stars and mountains are not built by nanomachines or encoded instructions. Thus, when we consider that both the structural complexity and the formation of stars/mountains differ significantly from that of living organisms, acceptance of (1) in the former cases does not automatically entail we accept it in the later case.

chance:
rather obvious I would think. I feel the author is confusing complexity with size.


I doubt the author is confusing anything.


QUOTE
First, it is well-known that small genetic changes over small periods of time can lead to large morphological changes. Unfortunately, most of the observed examples of such change are clearly deleterious. Yet a significant number of biologists throughout the years have proposed such "macromutations" to explain various evolutionary transitions

chance:
bold my emphasis, and that’s all it takes, as long as there is a beneficial trait that is passed on, that’s evolution. Micro/macro is a smokescreen.


It isn't all it takes, unless you want to bypass science and jump right into conclusion making by way of false extrapolations.


QUOTE
But what does this mean? It would mean that all of the fossil evidence is largely the consequence of trivial evolutionary events that have little meaning for the origin of much cellular machinery.

chance:
Partially agree with this, e.g. all mammals, reptiles, birds are basically all quadrupeds, we all have to breath oxygen, reseparate, so in a very real way there has been little change since the Devonian period (if you get my meaning) to me this show the common ancestry nature of living things. You could look at it like this, evolution changes a basic plan that does not change much.


To me it shows the common design in living things. It also tells me we have no idea how those metazoans came to be in the first place.


QUOTE
Attempts to justify this move by appealing to the use of (1) in astronomy and geology fail because biotic complexity differs in both structure and formation.

chance:
I still don’t get this part of the authors objection to evolution, but suspect it is to try to find an problem where non exists.


The problem is showing small changes, ie variations within a population, and then, without justification, extrapolating that observation into the premise that, for example, cetaceans can evolve from land animals.

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Posted 09 June 2005 - 09:21 PM

The problem is showing small changes, ie variations within a population, and then, without justification, extrapolating that observation into the premise that, for example, cetaceans can evolve from land animals.

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I understand the problem with extrapolating from small changes as it applies to the stack of pennies; the increasing instability which comes with greater height constitutes a barrier to change accumulating beyond a certain point. I don't understand the problem with extrapolating from small changes as it applies to genomes. What is the barrier? Is there any organism so perfecty designed that it could not possibly gain even the slightest advantage from a very small change -- even if placed in a new environment? Is it proposed that beyond some point no change can occur at all? It seems to me that the burden of evidence is on the one making the claim that small changes would not accrue to large ones; in the absence of any explanation to the contrary, the question seems to default to simple mathematics -- which would seem to demand that they accrue.


I also have problems with this bit:

"First, it is well-known that small genetic changes over small periods of time can lead to large morphological changes. Unfortunately, most of the observed examples of such change are clearly deleterious. Yet a significant number of biologists throughout the years have proposed such "macromutations" to explain various evolutionary transitions."

Looks like the guy got a little lost there. He started out talking about small changes, then, in mid-paragraph, switched to talking about large ones. It is true that a random change has a much greater chance of being deleterious than it does of being beneficial. In fact, the larger the change, the greater the chance of its being deleterious (for reasons that are intuitively obvious when one considers how many more ways there are of being wrong than there are of being right). Natural selection easily accounts for this. Various biologists (such as Goldschmidt) have indeed proposed models based on some form of macromutation, but it is worth noting that these proposals have not been very well recieved; the modern synthesis does not rely on any form of macromutation in the sense of large, single-step changes (regulatory genes are a special case).

#10 John Paul

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Posted 10 June 2005 - 05:40 AM

I understand the problem with extrapolating from small changes as it applies to the stack of pennies; the increasing instability which comes with greater height constitutes a barrier to change accumulating beyond a certain point. I don't understand the problem with extrapolating from small changes as it applies to genomes. What is the barrier? Is there any organism so perfecty designed that it could not possibly gain even the slightest advantage from a very small change -- even if placed in a new environment? Is it proposed that beyond some point no change can occur at all? It seems to me that the burden of evidence is on the one making the claim that small changes would not accrue to large ones; in the absence of any explanation to the contrary, the question seems to default to simple mathematics -- which would seem to demand that they accrue.


Where is the burden for those making the claim that small changes can accumulate in such a way as to give rise to the diversity of life from some unknown population of single-celled organisms? What are the experiments that show this? What, exactly, can be modified on an invertebrate as to give rise to vertebrates?

Genetic homeostasis is real. It has been observed in labs. It takes more than "just-so" stories to get around it.

As for mathematics- The Wistar Institute falsified the theory of evolution using mathematics. You know what Ernst Mayr said about that?

"Somehow or another by adjusting these figures we will come out all right. We are comforted by the fact that evolution has occurred"

Can anyone say dogma?

I also have problems with this bit:

"First, it is well-known that small genetic changes over small periods of time can lead to large morphological changes. Unfortunately, most of the observed examples of such change are clearly deleterious. Yet a significant number of biologists throughout the years have proposed such "macromutations" to explain various evolutionary transitions."

Looks like the guy got a little lost there. He started out talking about small changes, then, in mid-paragraph, switched to talking about large ones. It is true that a random change has a much greater chance of being deleterious than it does of being beneficial. In fact, the larger the change, the greater the chance of its being deleterious (for reasons that are intuitively obvious when one considers how many more ways there are of being wrong than there are of being right). Natural selection easily accounts for this. Various biologists (such as Goldschmidt) have indeed proposed models based on some form of macromutation, but it is worth noting that these proposals have not been very well recieved; the modern synthesis does not rely on any form of macromutation in the sense of large, single-step changes (regulatory genes are a special case).


Yeah I know the "hopeful monster" routine. It too is un-testable.

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Posted 10 June 2005 - 10:17 AM

Where is the burden for those making the claim that small changes can accumulate in such a way as to give rise to the diversity of life from some unknown population of single-celled organisms?

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Regardless of how it is phrased, it is still the same argument: "small changes cannot accrue to large changes". Before this thread gets locked for bogging down, I'd like to try one more time to see if I can get a direct answer to the objections being made to that claim.

We agree that changes in allele frequencies do occur. Presumably, it is also agreed that these changes are the result of natural selection and random mutation.

The problem with applying extrapolation from small changes to the stack of pennies is easily resolved by removing a specific constraint: that the pennies form a vertical stack. Once this constraint is removed -- and unless some other constraint is proposed -- the situation defaults to simple mathematics, which demand that the stack get bigger. Do we agree on that? The question then is: with regard to the genome, what constraint prevents accumulation of small change? And: if no specific constraint is proposed, why should not those claiming that small changes can accumulate in such a way be considered to have met the burden of proof on the basis of simple mathematics?

I have yet to see an argument that rises above the sort of crude appeal to common sense that head-scratchers like Zeno's paradox depend on: "we see small changes, yes, but we never see new species formed". Dawkins likened this to saying that the temperature of a teakettle on a stove rises degree by degree, but nowhere is there a point at which it ceases to be "cold" and becomes "hot"; therefore, it is impossible to make a cup of tea. He illustrates the fact that this sort of error in thinking is an artifact of human thought and its infatuation with category boundaries by dubbing this: "the tyranny of the discontinuous mind".

I'm going to address Genetic homeostasis in a separate post.

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Posted 10 June 2005 - 12:41 PM

We could do an entire thread on genetic homeostasis. Disclaimer: What I'm presenting here isn't the whole picture, it's just where I decided to start.

First, we have to recognize the difference between absolute fitness and relative fitness. Absolute fitness is concerned with traits as they relate to the ability of an organism to survive in a particular environment, while relative fitness is concerned with traits as they relate to an individual's ability to compete with others in a population. The two are not always complementary; for example, every ounce of fat expended by a bull in a duel with another bull is one less ounce of fat held in reserve against the onslaught of winter, yet the bull who avoids those battles may store up more fat and still leave fewer offspring.

Every organism has a 'natural range', where conditions such as temperature, sunlight, humidity, availability of food, etc, are best suited to that organism's survival. (The converse is not true, however; no organism can be considered 'optimally fit' to any environment, since the plethora of different solutions to any problem make that impossible to define -- absolute fitness cannot be defined absolutely).

Pretty much by definition, the conditions best suited to a particular organism will be found nearest the center of its range; start moving up the valley, or down the mountain, or away from the coast, or out of the forest, and conditions will become gradually harsher until a point is reached where that organism will not be able to survive at all. At the extreme edge, you may find some organisms just barely hanging on. Now, if those organisms can live long enough to reproduce, they might well produce some offspring with characteristics that would make them better suited to the harsh marginal conditions, but back toward the center of the range, the value of those traits in terms of absolute fitness would likely be of so little value in terms of relative fitness as to prevent them from gaining any traction at all within the population at large -- and gene flow from the population at large to the marginal group would render those traits so dilute as to prevent them from gaining any traction in the marginal group either. As long as significant gene flow was taking place between these marginal groups and the main population near the center of the range, the marginal groups are not likely to drive change in the population.

But if one of those groups became reproductively isolated from the main population, the strong selective pressure might produce much more rapid changes in the isolated group than those taking place within the main population. The descendants of such a group, re-introduced into the main population, could then introduce sweeping changes in its allele distribution. If the period of isolation was long enough to prevent interbreeding with the ancestral population, the new species could quickly supplant them. This is known as allopatric speciation, and (contrary to widely popularized misconception) is the main mechanism proposed by Gould and Eldredge to explain discontinuities in the fossil record (it is the application of Mayr's theory of allopatric speciation in peripheral isolates).

#13 John Paul

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Posted 10 June 2005 - 08:20 PM

QUOTE(John Paul @ Jun 10 2005, 05:40 AM)
Where is the burden for those making the claim that small changes can accumulate in such a way as to give rise to the diversity of life from some unknown population of single-celled organisms?


Regardless of how it is phrased, it is still the same argument: "small changes cannot accrue to large changes".


They are opposite arguments. I am asking for positive evidence that demonstrates mutations culled by any selection process can accumulate in such a way as to lead to the range of phenotypic & morphological change required if all of life's diversity owes its collective common ancestry to some unknown LUCA.

Before this thread gets locked for bogging down, I'd like to try one more time to see if I can get a direct answer to the objections being made to that claim.


Then don't bog it down.

We agree that changes in allele frequencies do occur. Presumably, it is also agreed that these changes are the result of natural selection and random mutation.


Yes and then No. Changes in allele frequencies do occur, and the evidence shows it leads to oscillations. IOW the beaks may vary, but the finch remains a finch.

We do not know if the mutations are random.

Dr. Spetner discussing mutations (Not By Chance):
"The motion of these genetic elements to produce the above mutations has been found to a complex process and we probably haven’t yet discovered all the complexity. But because no one knows why they occur, many geneticists have assumed they occur only by chance. I find it hard to believe that a process as precise and well controlled as the transposition of genetic elements happens only by chance. Some scientists tend to call a mechanism random before we learn what it really does. If the source of the variation for evolution were point mutations, we could say the variation is random. But if the source of the variation is the complex process of transposition, then there is no justification for saying that evolution is based on random events."

Natural selection is virtually meaningless as luck & chance play as important a role in survival as does some arbitrary definition of fitness. NS cannot build anything from scratch. There isn't any way to predict what would be selected for at any point in time. All hunters go for the biggest buck sporting the biggest rack. The fastest zebra is the first into the lioness ambush.

The problem with applying extrapolation from small changes to the stack of pennies is easily resolved by removing a specific constraint: that the pennies form a vertical stack. Once this constraint is removed -- and unless some other constraint is proposed -- the situation defaults to simple mathematics, which demand that the stack get bigger. Do we agree on that? The question then is: with regard to the genome, what constraint prevents accumulation of small change? And: if no specific constraint is proposed, why should not those claiming that small changes can accumulate in such a way be considered to have met the burden of proof on the basis of simple mathematics?


But simple mathematics has falsified the ToE. That is what led Mayr to say what he did.

Also the pennies would still reach a limit. The fact is limits exist in every aspect of life, including life itself. If you want us to believe that the evolutionary process is immune to limits the burden is upon you to show it. Throwing time at the issue, shaking your head, and saying "John Paul just doesn't get it", does nothing for me. And it isn't science.

I have yet to see an argument that rises above the sort of crude appeal to common sense that head-scratchers like Zeno's paradox depend on: "we see small changes, yes, but we never see new species formed". Dawkins likened this to saying that the temperature of a teakettle on a stove rises degree by degree, but nowhere is there a point at which it ceases to be "cold" and becomes "hot"; therefore, it is impossible to make a cup of tea. He illustrates the fact that this sort of error in thinking is an artifact of human thought and its infatuation with category boundaries by dubbing this: "the tyranny of the discontinuous mind".


But what constitutes a new species? As far as I know, speciation, even through its ambiguity, is not being debated. What is being debated is the formation of new body parts with novel functions- shells from the shell-less; bones from the bone-less; vertebrates from in-verts, yada, yada, yada.

I'm going to address Genetic homeostasis in a separate post.


Hopefully you will address why the people who claim mutations can accumulate as to lead to common descent from some LUCA do not have any burden to show that such a thing is even possible.

#14 Guest_Calipithecus_*

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Posted 10 June 2005 - 10:19 PM

Natural selection is virtually meaningless as luck & chance play as important a role in survival as does some arbitrary definition of fitness.

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I agree that luck and chance play an important role. But far from rendering selection meaningless, it is through chance and luck that selection is expressed; it is about probabilities: the race goes not to the swift, nor the battle to the strong, neither yet bread to the wise, etc -- they just have a better chance. Do you suppose that championship poker players are just lucky?


Since you brought up the pennies, let's see if we can at least get through that discussion before we head off in all these other directions (the randomness of mutation, the arbitrariness of the term: 'fitness', etc). I'd love to address those, really -- but I think this thing with the pennies is important.

"The pennies would still reach a limit" you say. Now, I agree with your earlier statement that science isn't about proof -- but since mathematics is (and since you seem to like mathematics), let's see if we can express your claim mathematically so that you can demonstrate your proof.

Unless I've missed something, your theorem is this:

For all positive numbers p and q, there exists some number p such that there exists no number p+q.

I feel that I must indeed have missed something -- perhaps you feel that there is something about the nature of pennies that renders them exempt from the ordinary rules of mathematics. If that is the case, I cannot imagine why you would be less interested in pointing it out to me than I am in having you do so.

#15 John Paul

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Posted 10 June 2005 - 10:34 PM

Are you ever going to answer the following?:


I am asking for positive evidence that demonstrates mutations culled by any selection process can accumulate in such a way as to lead to the range of phenotypic & morphological change required if all of life's diversity owes its collective common ancestry to some unknown LUCA.


Hopefully you will address why the people who claim mutations can accumulate as to lead to common descent from some LUCA do not have any burden to show that such a thing is even possible.



I don't understand your continued dodging of this issue.

And if you think you can pile pennies to infinity I really don't think we have much to discuss as it appears you aren't interested in a discussion.

On natural selection- A better chance does not mean better fit. Chance & luck are not hereditary. "Oh luck at Johnny- he was born with the luck gene."

Championship poker players are not just lucky. They also have to have the money to get in a game. In Texas hold-em they also have to know what combos are possible with the cards showing. So a lot of luck, a lot of money and some card savvy. Oh yeah, the ability to act also comes in handy.

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Posted 11 June 2005 - 07:22 AM

And if you think you can pile pennies to infinity I really don't think we have much to discuss as it appears you aren't interested in a discussion.

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Yes, we've clearly reached an impasse here. I feel that the burden of proof for the accumulation of small changes has been met by positive proof, in the form of the simplest of mathematical logic. You disagree, but are unable to say why, offering only vague, unsupported assertions like: "We know limits exist in life & to life itself". It doesn't look like it's going to get any better. Let's move on.

Maybe it would help if we can identify some points on which we do agree, at least in part.

NS cannot build anything from scratch

I agree -- no more than a sculptor can create statues out of thin air. It is mutation that produces the raw material.


There isn't any way to predict what would be selected for at any point in time

I don't disagree entirely with this, either. In certain environments, it might be easy enough to point to a particular trait and observe that -- all other things being equal -- organisms possessing that trait would tend to outpace the others reproductively; but in the real world, all other things never are equal.


But what constitutes a new species? As far as I know, speciation, even through its ambiguity, is not being debated.

That depends on whether you adhere to the idea that speciation is an important mechanism in producing significant change (see my post on allopatric speciation above). A statement like: "a finch is still a finch" is either an argument about speciation, or it's an argument about Platonic essences.


A better chance does not mean better fit. Chance & luck are not hereditary.

I agree with the second part of that.

#17 John Paul

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Posted 12 June 2005 - 09:59 PM

I feel that the burden of proof for the accumulation of small changes has been met by positive proof, in the form of the simplest of mathematical logic.


But mathematics have falsified that premise. The only thing Ernst Mayr had to say about that result was "Somehow or another by adjusting these figures we will come out all right. We are comforted by the fact that evolution has occurred."

NS cannot build anything from scratch

I agree -- no more than a sculptor can create statues out of thin air. It is mutation that produces the raw material.


And what do mutations do? They can muck things up or have no effect at all- most likely. If they do something it is only changing a protein/ enzyme, adding a protein/ enzyme or possibly effecting some other cellular-level chemical process. When a body plan is altered due to a mutation that effects development, it (the resulting offspring) is always deformed. Not the type of thing I would hang my hat on.

Speciation is just a dressed-up way to say variation. As in these two populations are variants of one parent population. And just as there isn't anything on a bicycle that could be varied (modified) to produce an engine, there isn't anything in an invertebrate that could be varied (modified) to produce a boned vertebrate.

And yes I understand geological isolation. But fresh water salmon are still salmon...

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Posted 12 June 2005 - 11:11 PM

But mathematics have falsified that premise.

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Actually, I believe that while the calculations to which you refer concluded that the available time was insufficient for the evolution of the eye, they assumed the accumulation of small changes. I can't seem to find any reference to what Ulam's assumptions were regarding rates of mutation, but if those assumptions were flawed, the results are worthless. The premise I propose:

For all positive numbers p and q, p+q > p.

makes no assumptions beyond the fundamental axioms of mathematics. You still haven't shown why pennies would not adhere to this logic. But I already agreed to drop it, so I'll let any response you have be the last word on the matter (that is, I promise to try even harder than I did this time to resist the temptation to respond further).


And what do mutations do? They can muck things up or have no effect at all- most likely.

Yes, I agree. Evolution requires that only the tiniest fraction be the exception to this general rule.


When a body plan is altered due to a mutation that effects development, it (the resulting offspring) is always deformed.

Yes, by definition. Now consider the rare case in which the deformity confers some advantage.


Speciation is just a dressed-up way to say variation.

It can be that. But the meaning of the term most pertinent to theoretical discussions (the biological species concept) is specifically concerned with important consequences for allele distribution which can occur only where there is reproductive isolation.

#19 chance

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Posted 13 June 2005 - 02:03 PM

QUOTE(John Paul @ Jun 9 2005, 08:07 AM)
Can it be tested & reproduced? If yes then it is valid. If used as a "hocus-pocus" then it isn't valid. IOW looking at variations within a population and adding time is not  scientifically valid when discussing the alleged evolution of cetaceans from land animals.

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Not directly, because it is acknowledged that time is a factor and evolution happens at the reproductive point. So if one wants to investigate evolution on complex life (mammals, reptiles etc) then you cant observe large changes and fossil evidence is used. I don’t se any way around this fact. Calling that a copout requires a counter explanation to what is found, If evolution were false, the fossil record should not show any lineage, but it does.

The fossil record can't tell us anything about a mechanism. IOW we don't know how the organisms that are represented in the fossil record came to be.

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Not 100%, but as you know a theory is tentative and is currently the best we have to explain the evidence, to topple evolution you will need a better theory.

No we would not. Life is more than DNA.

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Agreed, but my objection to the ‘expander’ was in context to the original flawed analogy.


I doubt the author is confusing anything.

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Then I’ll ask you, what is more complex an amoeba or a star?

It isn't all it takes, unless you want to bypass science and jump right into conclusion making by way of false extrapolations.

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I don’t understand your objection, can you clarify please.



To me it shows the common design in living things. It also tells me we have no idea how those metazoans came to be in the first place.

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I think I could make a better argument for ‘common poor design’ as life is a hotchpotch of adaptations.

#20 John Paul

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Posted 14 June 2005 - 05:27 AM

chance:
Not directly, because it is acknowledged that time is a factor and evolution happens at the reproductive point. So if one wants to investigate evolution on complex life (mammals, reptiles etc) then you cant observe large changes and fossil evidence is used. I don’t se any way around this fact. Calling that a copout requires a counter explanation to what is found, If evolution were false, the fossil record should not show any lineage, but it does.


On other discussion boards I am told that Creation isn't science because it isn't supported via experimentation. Here I am told that the ToE is exempt from that criteria.


QUOTE(John Paul @ Jun 9 2005, 10:30 PM)
The fossil record can't tell us anything about a mechanism. IOW we don't know how the organisms that are represented in the fossil record came to be.

chance:
Not 100%, but as you know a theory is tentative and is currently the best we have to explain the evidence, to topple evolution you will need a better theory.


Theories stand or fall on their own. If a theory is falsified another theory doesn't have to take its place before it is scrapped.


QUOTE(John Paul @ Jun 9 2005, 10:30 PM)
No we would not. Life is more than DNA.

chance:
Agreed, but my objection to the ‘expander’ was in context to the original flawed analogy.


What flaw?



QUOTE(John Paul @ Jun 9 2005, 10:30 PM)
I doubt the author is confusing anything.


chance:
Then I’ll ask you, what is more complex an amoeba or a star?


What does that have to do with anything?


QUOTE(John Paul @ Jun 9 2005, 10:30 PM)
It isn't all it takes, unless you want to bypass science and jump right into conclusion making by way of false extrapolations.

chance:
I don’t understand your objection, can you clarify please.





QUOTE(John Paul @ Jun 9 2005, 10:30 PM)
To me it shows the common design in living things. It also tells me we have no idea how those metazoans came to be in the first place.


I think I could make a better argument for ‘common poor design’ as life is a hotchpotch of adaptations.




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