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Author Topic:   Evolution and the BIG LIE
RAZD
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Message 1 of 108 (440999)
12-15-2007 6:57 PM


There are several threads (definition of evolution, definition of the theory of evolution, etc) and posts that mention evolution on this forum, but I want to discuss what evolution is - as a process, as a theory and as a scientific field of study - in one combined thread, and what any competing ideas regarding evolution involve and how we can test concepts of evolution against reality to determine which concepts explain the evidence and which ones do it best.

We'll start with the process, where evolution is the change in hereditary traits in populations from generation to generation

Where:
trait is an aspect that can be quantified, such as an allele or variation of a gene, the length of a bone, the size of a skull, the color of an eye, the thickness of hair,
change is a measurable quantifiable difference in a trait, such as the number, length or color,
hereditary means that it is passed from parent to child,
population means a group of individual organisms of the same species, and
generation is the average time it takes for a newborn to become able to reproduce.

You don't have to take my word for this, you can look these up and see how they are used, just be sure to stick to usage within the science of biology, seeing as that is what we are talking about.

Evolution is a process that is observed in everyday life: there is no species that does not change hereditary traits in populations from generation to generation. This process is an observed fact, and this is the objective evidential basis for the "Theory of Evolution" (ToE), and then both become the foundation of the science of Evolutionary Biology.

Astute creationists will notice that this is "just variation and adaptation within kinds" or "microevolution" which has become a well accepted fact even in these circles (as has a heliocentric solar system). That's the good news: creationists should not be concerned about evolution as defined here. The next question then is "what is the controversy all about," and how does this relate to "the rest of the story."

Darwin, Descent with Modification and Time

On 24 November 1859 Darwin published On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life, where he first described “descent with modification” and established his theory of natural selection. He does not use the word "evolution" but he does say:

quote:
He who can read Sir Charles Lyell's grand work on the Principles of Geology, which the future historian will recognise as having produced a revolution in natural science, yet does not admit how incomprehensibly vast have been the past periods of time, may at once close this volume.

When the views entertained in this volume on the origin of species, or when analogous views are generally admitted, we can dimly foresee that there will be a considerable revolution in natural history.



At that time geologists and other scientists had already determined that the earth was much older than was previously thought. He refers to Lyell's "the Principles of Geology" as one reference to geological age. Meanwhile, Lord Kelvin working from principles of thermodynamics shortly before Darwin's book had come to the conclusion that:
quote:
"This earth, certainly a moderate number of millions of years ago, was a red-hot globe ... ."[29]

and after the book was published he
quote:
... settled on an estimate that the Earth was 20-40 million years old. Shortly before his death however, Becquerel's discovery of radioactivity and Marie Curie's studies with uranium ores provided the insight into the 'energy source beyond' that would power the sun for the long time-span required by the theory of evolution.

This means that at that time the minimum age of the earth from sources outside biology was 20 million years, and probably a lot older due to the addition of radioactivity into the equations.

Darwin came to his conclusions based on comparison to animal breeding and his discoveries of existing life in various parts of the world, most notably the Galapagos Islands. He based his concept on what he knew about existing life, not on the fossil record. Not on rocks, organic soup or single cell organisms, and not on the evolution of man (his book on The descent of man, and selection in relation to sex was published in 1871). He noticed that life changed (modification), that those changes were hereditary (descent), that natural selection had to be involved because there were more offspring produced than were necessary, and that this predicted that there was a mechanism for developing new traits and transferring hereditary information from one generation to the next even though he did not know what it was.

Embryology, Evolution and Genetics

In 1900 the work of Mendel (originally published in 1866) was rediscovered by scientists working on plant physiology and then it was spread to embryology by Bateson, and this led to the further developments in biology by Haeckel, de Beers and others, leading to the use of the term evolution in studying how life develops and (ultimately) to genetics and the study of how genetic hereditary traits are passed from parent to offspring. While genetics was able to show that traits were inherited through chromosomes and genes, it took until the 1950's to link this to DNA. During that time there were a lot of theories that were proposed tested and discarded on how hereditary traits where physically transferred from parent to child before the truth was finally understood.

From 1936 to 1947 the modern synthesis was developed to combine the study of genetics with Darwinism based on morphology and fossils, and they concluded that “evolution consists primarily of changes in the frequencies of alleles between one generation and another as a result of genetic drift, gene flow, and natural selection” ...

Definitions used in Science

Evolutionary Biology is taught by many universities as part of their various degree programs for biologists, culminating in Ph.D.s, so if we want to look for modern definitions of evolution as used in science then we can look to how universities that teach these programs define it.

the University of California Museum of Paleontology, Berkeley definition is “evolution, simply put, is descent with modification”

The University of Michigan defines evolution as “changes in the genetic composition of a population with the passage of each generation” and the “gradual change of living things from one form into another over the course of time, the origin of species and lineages by descent of living forms from ancestral forms, and the generation of diversity” ...

The Massachusetts Institute of Technology (MIT) (Population Genetics) definition is “evolution is a change in the frequency of alleles within the gene pool of a population from one generation to the next”

One of the areas where evolution has seen new developments is the field of evolutionary developmental biology, "a field of biology that compares the developmental processes of different animals and plants in an attempt to determine the ancestral relationship between organisms and how developmental processes evolved."

quote:
Some evo-devo researchers see themselves as extending and enhancing the modern synthesis by incorporating into it findings of molecular genetics and developmental biology. Others, drawing on findings of discordances between genotype and phenotype and epigenetic mechanisms of development, are mounting an explicit challenge to neo-Darwinism.

This can also include the effects of environment on the development of individual genotypes into adult forms, the phenotype that is the subject of natural selection.

Conclusions

(1) The scientific definitions from universities are consistent with the definition that evolution is the change in hereditary traits in populations from generation to generation,

(2) That this is consistent with "variation and adaptation within kinds" or "microevolution" as used by creationists, and thus that creationists should not be concerned about evolution as defined here.

(3) This thread is long enough already.

But wait --- what's the BIG LIE?

The big lie is what creationists say about evolution, that evolution is a problem for creationist beliefs, that there is something else to evolution than the change in hereditary traits in populations from generation to generation or that this is NOT evolution (but will they define what is?).

If nobody objects to this definition of evolution, or you just agree to it for the sake of the argument, then we can move on to what the definition of "the Theory of Evolution" (ToE) contains, and see what develops, something that is a problem for creationism.

Enjoy.

Edited by RAZD, : added

Edited by RAZD, : pop in def list


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AdminNosy
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Message 2 of 108 (441003)
12-15-2007 7:12 PM


Thread moved here from the Proposed New Topics forum.
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Beretta
Member (Idle past 3822 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 3 of 108 (441059)
12-16-2007 8:50 AM
Reply to: Message 1 by RAZD
12-15-2007 6:57 PM


that evolution is a problem for creationist beliefs

Natural selection and variation within kinds is no problem.Evolution in the macro sense is not a problem for creationist beliefs, it is a problem full stop because it does not explain what we actually see. The usual icons given as proof for macroevolution all over the world are exaggerated or distorted and are not presented in a balanced way showing their shortcomings. If evolution is such a 'fact' -why are they not replaced with more convincing examples?

evolution is the change in hereditary traits in populations from generation to generation,

That this is consistent with "variation and adaptation within kinds" or "microevolution" as used by creationists, and thus that creationists should not be concerned about evolution as defined here.

They are not concerned with that definition but with the extrapolation that is implied and includes supposition of common ancestry and origin of life arising from chemicals through purely naturalistic processes.How much is real science and how much is pure materialistic philosophy?


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Larni
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Posts: 3986
From: Liverpool
Joined: 09-16-2005
Member Rating: 5.9


Message 4 of 108 (441060)
12-16-2007 8:55 AM
Reply to: Message 3 by Beretta
12-16-2007 8:50 AM


Beretta writes:

it is a problem full stop because it does not explain what we actually see.

Please explain how this is so.

Beretta writes:

The usual icons given as proof for macroevolution all over the world are exaggerated or distorted and are not presented in a balanced way showing their shortcomings.

Examples would be?


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nator
Member (Idle past 395 days)
Posts: 12961
From: Ann Arbor
Joined: 12-09-2001


Message 5 of 108 (441062)
12-16-2007 9:07 AM
Reply to: Message 3 by Beretta
12-16-2007 8:50 AM


quote:
Natural selection and variation within kinds is no problem.

What is the definition of "kind"?

Specifically, what method or system do I use to determine one "kind" from another?

For example, are my housecats the same "kind" as a Bengal tiger?

Are Bonobo Chimpanzees the same "kind" as homo sapiens?

Is it useful to use genetic similarity to determine if an organism is the same "kind" as another, and also how closely related one "kind" is from another?


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RAZD
Member
Posts: 20028
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.9


Message 6 of 108 (441116)
12-16-2007 1:07 PM
Reply to: Message 5 by nator
12-16-2007 9:07 AM


we have a thread for defining kinds: Problems of a different "Kind"

This thread is about the different types of evolution.


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RAZD
Member
Posts: 20028
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.9


Message 7 of 108 (441120)
12-16-2007 1:14 PM
Reply to: Message 4 by Larni
12-16-2007 8:55 AM


perhaps we can come back to this when we get to macroevolution.
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RAZD
Member
Posts: 20028
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.9


Message 8 of 108 (441122)
12-16-2007 1:22 PM
Reply to: Message 3 by Beretta
12-16-2007 8:50 AM


Thank you Beretta
Natural selection and variation within kinds is no problem.

This is the first fact to learn about evolution: this is what evolution is, the change in hereditary traits in populations from generation to generation.

Evolution in the macro sense is not a problem for creationist beliefs, it is a problem full stop because it does not explain what we actually see. The usual icons given as proof for macroevolution all over the world are exaggerated or distorted and are not presented in a balanced way showing their shortcomings. If evolution is such a 'fact' -why are they not replaced with more convincing examples?

We can get to that when we get to macroevolution, or you can continue our discussion on the Dogs thread (I'll get to you there next).

They are not concerned with that definition but with the extrapolation that is implied and includes supposition of common ancestry and origin of life arising from chemicals through purely naturalistic processes.How much is real science and how much is pure materialistic philosophy?

And we'll cover this after we cover what the "Theory of Evolution" (ToE) is, as that is a major part of the answer.

Looks like we can move on then.

Enjoy.


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RAZD
Member
Posts: 20028
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.9


Message 9 of 108 (441282)
12-16-2007 11:21 PM
Reply to: Message 1 by RAZD
12-15-2007 6:57 PM


Part 2 - the Theory of Evolution - hidden for now.
Content hidden until discussion returns to this level. Use {peek} so see if you need to.

In part 1 we established three (3) things:

(1) Evolution is the change in hereditary traits in populations from generation to generation

Where:
trait is an aspect that can be quantified, such as an allele or variation of a gene, the length of a bone, the size of a skull, the color of an eye, the thickness of hair,
change is a measurable quantifiable difference in a trait, such as the number, length or color,
hereditary means that it is passed from parent to child,
population means a group of individual organisms of the same species, and
generation is the average time it takes for a newborn to become able to reproduce.

(2) that creationists should not be concerned about evolution as defined here, because this is the same as "variation and adaptation within kinds" or "microevolution" within their views and well accepted in creationist circles.

(3) that this was based on observation of changes in life in the present, not in the past or in the fossil record.

This is the basic evidence necessary for the Theory of Evolution (ToE).

In science, theories are based on evidence, evidence that is extensively reviewed for trends and tendencies, and then a conclusion is deduced, that {X} is caused by {Y}.

Darwin's big insight in his first book On the origin of species ...etc, was not that evolution was an on-going process (other people had noticed that), or that natural selection was a driving force (other people had noticed that), but that this process of evolution was sufficient to explain the diversity of life we know, from the present day to the fossil record.

He was not alone in this, Wallace had come to very much the same conclusions from the evidence around him in the Malay Archipelago (or the "East Indies," now Malaysia and Indonesia), and he recognized the importance of geographical barriers to diversity (See "Wallace Line"), which was instrumental to the early development of biogeography and speciation models.

So one way we can state the "Theory of Evolution" today is:

The Theory of Evolution is that the change in hereditary traits in populations from generation to generation - evolution - is sufficient to explain all the diversity of life we know, in the present, in history, in the fossil record, and in the genetic record.

That's pretty grandiose, but somewhat cumbersome, and one of the problems with this statement of the theory is that it does not describe how evolution actually occurs, the mechanism/s to the process. We now have several mechanisms from Darwin's original natural selection to modern genetics mechanisms for mutations in genes\DNA, to other population mechanisms like neutral genetic drift and epigenetic factors. Each of the different mechanisms can be considered a theory for part of the whole sum total process (Darwin's theory of Natural Selection, mutation theory, germ theory, Gould/Eldridge's theory of Punctuated Equilibrium and other population dynamics theories, Fisher's Runaway Sexual Selection theory, various "mimicry" theories, epigenetic theories, etc), some of which are important in some situations while others are more important in different situations.

Thus modern evolutionary biology has developed a very wide range of theories covering a lot of different aspects of evolution as the science has matured. So the question is, how can we practically cover all these mechanisms within the "Theory of Evolution?" We can do this with a number of different levels of conciseness or detail.

In modern evolutionary biology the Theory of Evolution is that all the diversity of life (the natural history of life from the present day, to history, to the fossil record and the genetic record), is explained by:

(1) a synthesis of several validated theories on how hereditary traits in populations change from generation to generation.

(2) a synthesis of several validated theories on how hereditary traits in populations change from generation to generation; it includes theories on how change is enabled, and it includes theories on how changes made within each generation are selected.

(3) a synthesis of several validated theories on how hereditary traits in populations change from generation to generation; it includes theories on how change is enabled, due to the available variations (diversity) within populations from the formation and accumulation of different mutations in hereditary traits, and it includes theories on how changes made within each generation are selected, due to the differential response of organisms under prevailing ecological pressures to their individual development, their ability to pass on hereditary traits to the next generation, and their opportunities to disperse into other ecological habitats.

(4) a synthesis of several validated theories on how hereditary traits in populations change from generation to generation; it includes:

  • theories on how change is enabled
  • (list of theories on different mechanisms for the formation and accumulation of different mutations in hereditary traits within populations)
  • theories on how changes made within each generation are selected
  • (list of theories on different mechanisms of selection and where and when they operate)
  • etc
Now it may be interesting to flesh out #4 with the lists of theories from natural selection to genetic drift to punk-eek to runaway sexual selection ... etc, but that is beyond the scope of this post.

So a second (concise version) way we can state the "Theory of Evolution" today then is:

The Theory of Evolution is that all the diversity of life is explained by a synthesis of several validated theories on how hereditary traits in populations change from generation to generation.

This solves the problem noted with the first statement for the theory, but there are a couple of things to notice about this statement of the theory, and they are:

(1) it is not a single theory but a synthesis, a compilation of contributory theories that all together add up to the Theory of Evolution.

(2) each of those individual contributory theories can be falsified (invalidated), and need to be revised, replaced or abandoned.

(3) invalidating contributory theories does not invalidate the overall synthesis, for that just changes the mix of contributory theories, and this makes it a robust theory, standing on many legs.

(4) the Theory of Evolution can be tested by all the evidence known to see if it is sound or invalidated by any piece of evidence from the natural history of life, from the present day, to history, to the fossil record and the genetic record.

(5) this still only involves mechanisms for "variation and adaptation within kinds" or "microevolution" as used by creationists, and thus that creationists should not be concerned about the Theory of Evolution as defined here.

Conclusions

(1) The Theory of Evolution can be stated several ways, with a concise statement being that the Theory of Evolution is that all the diversity of life is explained by a synthesis of several validated theories on how hereditary traits in populations change from generation to generation.

(2) That IF the definition still only involves mechanisms for "variation and adaptation within kinds" or "microevolution" as used by creationists, AND "macroevolution" truly IS a different process, that THEN this theory will not be able to explain anything more than microevolution, and testing it against all the evidence should invalidate it. Thus creationists should not be concerned about the Theory of Evolution as defined here.

(3) The real issue, then, is testing the theory against the evidence to see how far it can explain the evidence.

But wait --- what about that BIG LIE?

The big lie is still what creationists say about evolution, that evolution is a problem for creationist beliefs, that there is something else, something evolution can't explain, that the "Theory of Evolution is that the diversity of life is explained by a synthesis of several validated theories on how hereditary traits in populations change from generation to generation" is NOT all there is to evolution and that it is NOT sufficient to explain all the diversity of life. But how do we know this without testing it?

If nobody objects to this definition of the Theory of Evolution, or you just agree to it for the sake of the argument, then we can move on to what Evolutionary Biology, the "Science of Evolution" involves, and see what develops, and see if that presents a problem for creationism.


Enjoy.

Edited by RAZD, : hiding text for discussion on Part 1 to catch up


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mobioevo
Member (Idle past 4169 days)
Posts: 34
From: Texas
Joined: 12-13-2007


Message 10 of 108 (441290)
12-16-2007 11:59 PM
Reply to: Message 9 by RAZD
12-16-2007 11:21 PM


the Theory of Evolution definition
RAZD writes:

The Theory of Evolution is that all the diversity of life is explained by a synthesis of several validated theories on how hereditary traits in populations change from generation to generation. (Italics added for emphasis)

I think you should state or make more clear the "several validated theories" that you refer to so that there is no ambiguity to creationists or students of evolution in what you mean. This may seem cumbersome but I think it will bring more validity to your definition if you keep vague words out.


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Beretta
Member (Idle past 3822 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 11 of 108 (441306)
12-17-2007 1:34 AM
Reply to: Message 4 by Larni
12-16-2007 8:55 AM


Icon Problems
Larni writes:

Beretta writes:
it is a problem full stop because it does not explain what we actually see.

Please explain how this is so.

Well quite simply if gradualistic evolution is true, what about the cambrian explosion which defies explanation in gradualistic terms.

Larni writes:

Beretta writes:
The usual icons given as proof for macroevolution all over the world are exaggerated or distorted and are not presented in a balanced way showing their shortcomings.

Examples would be?

Human evolution
Homology arguments
Origin of Life from lifeless chemicals
Four winged Fruit flies
Haeckel's Embryos etc....


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Beretta
Member (Idle past 3822 days)
Posts: 422
From: South Africa
Joined: 10-29-2007


Message 12 of 108 (441309)
12-17-2007 1:46 AM
Reply to: Message 8 by RAZD
12-16-2007 1:22 PM


Re: Thank you Beretta
This is the first fact to learn about evolution: this is what evolution is, the change in hereditary traits in populations from generation to generation.

I would say that that is not what 'evolution' is, it is only what 'microevolution' is -the definition does not do justice to all that is implied by the word 'evolution'.


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Kitsune
Member (Idle past 2525 days)
Posts: 788
From: Leicester, UK
Joined: 09-16-2007


Message 13 of 108 (441319)
12-17-2007 3:01 AM
Reply to: Message 12 by Beretta
12-17-2007 1:46 AM


Re: Thank you Beretta
If you accept that microevolution can occur, then what is to stop it from becoming macroevolution over a longer stretch of time, as more and more changes accumulate?
This message is a reply to:
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Kitsune
Member (Idle past 2525 days)
Posts: 788
From: Leicester, UK
Joined: 09-16-2007


Message 14 of 108 (441321)
12-17-2007 3:12 AM
Reply to: Message 11 by Beretta
12-17-2007 1:34 AM


Re: Icon Problems
Well quite simply if gradualistic evolution is true, what about the cambrian explosion which defies explanation in gradualistic terms.

The simple answer to this is that the term "explosion" is misleading. The diversification of organisms in this period is estimated to have occurred over a range of about 30 million years. What's more, in order to be available to us as fossils, certain conditions must be met in the biochemical makeup of the organism, and the conditions in which it died; the sparseness of the pre-Cambrian fossil record is believed to reflect some difficulties in meeting those conditions. You can read about it here.

However, if you look at RAZD's definition of evolutionary theory, he talked about it being a synthesis of different theories. Lack of gradualism is often only apparent rather than factual, and this topic has already been addressed in theories by well-known evolutionary scientists, Gould and Eldredge for example.

Your list at the end of this post is OT here as we are discussing the definition of evolution, the theory of evolution, and evolutionary biology. However, I have seen each one of these things addressed in other topics on the forum if you'd care to have a look.


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crashfrog
Inactive Member


Message 15 of 108 (441324)
12-17-2007 3:17 AM
Reply to: Message 11 by Beretta
12-17-2007 1:34 AM


Re: Icon Problems
Well quite simply if gradualistic evolution is true, what about the cambrian explosion which defies explanation in gradualistic terms.

Uh, it really doesn't. The so-called "explosion" refers to the emergence of no more than about 8000 different species over a period of around 50 million years.

Not much of an explosion, really. It doesn't really "defy explanation"; random mutation and natural selection account for the origin of those species just as well as they account for the species we see evolving today. The fact that most of these 8000 species appear in the fossil record with relatively few known precursors is easily explained by the fact that those 8000 species were largely hard-shelled organisms whose ancestors had no hard body parts to speak of, and therefore nothing to fossilize.

Edited by crashfrog, : No reason given.


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