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Bibleland
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USA
51 Posts

Posted - 03/30/2006 :  18:00:23  Show Profile  Visit Bibleland's Homepage Send Bibleland a Private Message
Still trying to understand the theory of natural selection from an evolutionists perspective. Here's the question. Do you believe that natural selection ever moves an organism from more complex to less complex? Do you ever see natural selection of an organism go from larger to smaller. If natural selection is unbiased in that it does not care either way it manifests itself (larger or smaller, complex or less complex), how do we determine that one fossil that is smaller is such and such an age. And the larger is such and such an age if all we have to go on is the type and size? Why does is seem we say that natural selection is unbiased but yet it appears the move forward is more complex and larger. Is there a thing called Carroll's Law? Does the survival of the fittest mean you can have less smart and less complex and less larger? Any examples of this being so? Thank you.

furshur
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USA
1536 Posts

Posted - 03/30/2006 :  18:15:34   [Permalink]  Show Profile Send furshur a Private Message
quote:
Do you believe that natural selection ever moves an organism from more complex to less complex?

Sure
quote:
Do you ever see natural selection of an organism go from larger to smaller.

Sure
quote:
If natural selection is unbiased in that it does not care either way it manifests itself (larger or smaller, complex or less complex), how do we determine that one fossil that is smaller is such and such an age. And the larger is such and such an age if all we have to go on is the type and size?

The age of a fossil has nothing to do with the size. It only has to do with the age of the strata it was found in.
quote:
Why does is seem we say that natural selection is unbiased but yet it appears the move forward is more complex and larger.

It doesn't. Infact just 15,000 years ago was a time of Megafauna. During an ice age larger is better for warm blooded animals.
quote:
Does the survival of the fittest mean you can have less smart and less complex and less larger? Any examples of this being so? Thank you.

I think the best examples of this are animals on islands. The Key deer comes to mind which is a resident of the Florida keys and is a type of white tail deer that is about the size of a collie. 'Dwarf' mammoths on the channel islands also come to mind.

Hope this helps.


edited for spelling


If I knew then what I know now then I would know more now than I know.
Edited by - furshur on 03/30/2006 18:18:48
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filthy
SFN Die Hard

USA
14408 Posts

Posted - 03/30/2006 :  18:22:08   [Permalink]  Show Profile Send filthy a Private Message
Hi Bible, and welcome back!

Excellent question! I am not qualified to give you a complete answer, but I can state that yes, natural selection can indeed make a species less complex. For an example, blind cave fish once had working eyes and now have only the remnants.

This is by no means any sort of de-evolution. It is simply a species better fitting into it's niche in the ecology. "Use it or lose it", as it were. The same holds for so-called dwarf species, and indeed, the giants found in some island habitats.

The Santa Catalina rattlesnake is in the process of losing it's rattle.

As for man evolving back to an amoeba (I've actually seen this one in a very bitter argument on another forum), it ain't likely.




"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)

"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres


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Hawks
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Canada
1383 Posts

Posted - 03/30/2006 :  18:53:33   [Permalink]  Show Profile  Visit Hawks's Homepage Send Hawks a Private Message
A good example of an organism getting less complex (probably by most definitons) compared to its ancestors would be Mycoplasma genitalium. It is thought to be most closely related to Lactobacillus and contains less than 500 genes (compared to Lactobacillus more than 1900 genes).

quote:
Why does is seem we say that natural selection is unbiased but yet it appears the move forward is more complex and larger.
Natural selection has no intrinsic bias towards size or "complexity". However, if size or complexity should lead to differential survival, then yes, natural selection would be biased.
quote:
Is there a thing called Carroll's Law?

Never heard of it. What is it supposed to be?

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Hawks
SFN Regular

Canada
1383 Posts

Posted - 03/30/2006 :  20:47:30   [Permalink]  Show Profile  Visit Hawks's Homepage Send Hawks a Private Message
Also, if you want to equate loss of complexity with the loss of genes, then it is fairly common for bacteria to loose plasmids (a plasmid is a circular DNA molecule found in both bacteria and some eukaryotes).

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beskeptigal
SFN Die Hard

USA
3834 Posts

Posted - 03/31/2006 :  01:56:23   [Permalink]  Show Profile Send beskeptigal a Private Message
I should like to add that your description of natural selection being unbiased is not exactly correct. And instead of survival of the fittest or even the term natural selection biology has adopted the more accurate descriptive term, selection pressures.

Consider all multi-celled sexually reproducing life forms and many single celled organisms to be full of genetic code including lots of redundant genes as well as lots of variation that isn't being selected or rejected but nonetheless is spread if the whole organism is successful. Humans for example have duplicate genes for everything except those in males who have an x and y chromosome, (females have 2 x chromosomes). Many very serious genetic defects don't show up unless two defective copies are inherited. That allows for an awful lot of errors without killing the organism. In addition, there is a lot of variation in our genetic code which doesn't affect our ability to reproduce. In fact, variation benefits the organism and is therefore selected.

The result of these characteristics of our DNA allow a wide variety of selection pressures to occur and as a species we continue to reproduce. Take the plague which had a high fatality rate, yet it didn't kill everyone who became infected. That wasn't because a mutation occurred at the time of the epidemic. It was because a variation already existed within the population which provided resistance to the bacteria or its toxins.

Selection pressures can be anything from mate preference to infection to climate to food sources and so on. Most people think of survival of the fittest in much too oversimplified terms. The human genome has some 20-30,000 genes and ~3 billion base pairs of nucleic acids. It isn't just being the alpha dog that gives you the most offspring. There are a vast number of variables which give us a vastly varied population.

Also, you cannot assume because an organism looks simple that it is less complex than one which appears complex. There are bacteria which have more genes than humans. So you have to define what you mean by more complex and less complex. Intelligence is a very handy tool. So to see evolution of larger and larger brain size might be expected. Anything can come along and reverse that. Intelligent people might have fewer children, for example. Then something else comes along and reverses things again. People with too many children are less able to avoid disease and starvation.

I do think some survival tactics like intelligence will prevail over time so to say evolution is neutral as you describe it is probably incorrect. If there is some planetary catastrophe which wipes out 90% of the species on the planet, there may not be a guarantee intelligence will be sufficient to save the human species. Perhaps only very tiny creatures will survive. In a case such as that you might be closer to the definition of evolution being unbiased as you say. Otherwise evolution is biased. It's biased toward what ever the selection pressures are directing it.
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filthy
SFN Die Hard

USA
14408 Posts

Posted - 03/31/2006 :  02:35:46   [Permalink]  Show Profile Send filthy a Private Message
I too, was wondering about Caroll's Law so I picked up my shovel and went looking for it. And found it.... I think..... Maybe.
quote:
Call it Carroll's law, because what I've learned is this -- those doomed to extinction and other severe career implications as a result of rapid change, are usually the least receptive to a message as to the reality of their impending doom. They would prefer to escape rather than adapt to reality.

Ok, if this is it, Mr. Caroll is referring to social evolution and changing industrial climates. I suppose that it could be transferred over to evolution of species except that it deals with individuals.

Individuals do not evolve; only species. And even then, some populations of that species might, and probably will, evolve in different directions than others, and even at a higher rate. Thus, there are still apes on the planet as well as H. sapiens. Indeed, it can be easily seen in those apes as well. The differences between a chimp and a gibbon are vast. Add a gorilla and an orangutan to the equation, and the differences become enormous.




"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)

"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres


"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude

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beskeptigal
SFN Die Hard

USA
3834 Posts

Posted - 03/31/2006 :  12:34:21   [Permalink]  Show Profile Send beskeptigal a Private Message
I think you may have the wrong material, Filthy. I found two candidates out of about 10 different Carrolls that came up on a Google search of [Carroll's law evolution], but I'm pretty sure Bibleland was referring to Sean Carroll.

Sean Carroll
quote:
The control regions of the genes (switches that change an existing pattern of gene activity into a new pattern of gene activity) are crucial, as Carroll makes clear, and one gene can have many control regions.

Carroll emphasizes that individual animals are made up of similar parts, such as vertebrae, bones in fingers and spots on butterfly wings, and that modular construction played an important role in evolution. He is a supporter of Williston's law, which states that "in evolution . . . the parts in an organism tend toward reduction in number, with the fewer parts greatly specialized in function."...


Sean Carroll also has a book, Endless Forms Most Beautiful: The New Science of Evo Devo and the Making of the Animal Kingdom. Read the introduction from the Amazon link and it explains the concept. Actually, this work, from what I can tell, is consistent with genetic research discoveries in the last decade. Evo Devo is evolution de-evolution which fits with the OP. But I see nothing suggesting any "Carroll's law". And I wonder if Bibleland really meant, Williston's law.

Description, example and counter example of Williston's Law. This page explains it all and answers Bibleland's question. Clearly selection pressures determine the direction of evolution. I suspect Bibleland, from his forum name, is looking for something to refute evolutionary theory. Nice try but no dice.




There was also a Robert Carroll.
quote:
WHAT ABOUT THE HUNDREDS OF SCIENTISTS "OPPOSING DARWINISM" ?

IDers, and IDnet-NM in particular, deliberately and repeatedly confuses the concept of "evolution" - the descent of many varied species from common ancestors - with the concept of "Darwinism' which is the gradual unfolding of variations by natural selection espoused by Charles Darwin in 1859. IDnet-NM purposely equates any and all criticisms of Darwin's original work with criticisms of the idea of "evolution" itself.

From IDnet-NM's http://www.nmidnet.org/new_mexico_speaks.htm :
In the preface and first chapter of his book, Patterns and Processes of Vertebrate Evolution, [Robert] Carroll makes some extraordinary statements about pervasive problems in the history of life constructed from examination of the fossil record compared to the history predicted by Darwin. He even criticizes textbooks for perpetuating this false history. Here is Carroll.

"Instead of showing gradual and consistent change through time, the major lineages appear suddenly in the fossil record, already exhibiting many of the features by which their modern representatives are organized."

"..few fossils are yet known of plausible intermediates between the invertebrate phyla, and there is no evidence for the gradual evolution of the major features by which the individual phyla or classes are characterized"

"Progressive increase in knowledge of the fossil record over the past hundred years emphasizes how wrong Darwin was in extrapolating the pattern of long-term evolution from that observed within populations and species."

Carroll indeed makes such statements. But, he was talking about the state of evolution as it was known in Darwin's time -1859. In the fourteen decades since, we've made many new discoveries. Carroll points out that continental drift has had a huge impact on the course of evolution over time scales of hundreds of millions of years, yet it was not even accepted until about 1960. Yes, there are indeed gaps in the fossil record, but these can be caused by several mechanisms, including migration and mutations in regulatory genes. If a species evolves in one region, and then migrates to a new region, the fossil record would show a "sudden appearance" of the species in the second region. For example, future New Mexican scientists might uncover evidence of a "sudden appearance" of Africanized Killer Bees in New Mexico, in the late 20th and early 21st centuries. The bees evolved, all right, but in Africa, not in America. Their "sudden appearance" in New Mexico is no more mysterious than the "sudden appearance" of distant relatives during holiday seasons.

Carroll also discusses how mutations in regulatory genes - genes that control other genes, like the homeobox (Hox) genes - can produce massive changes in body plans, using conventional hereditary mechanisms. Carroll indeed takes issue with Darwin's predictions, because these were primarily derived from observations of living creatures alone, and did not take into account what we've learned from hundreds of millions of years worth of fossil data. Carroll writes in his preface "Although Mendelian and population genetics are important for understanding the mechanics of evolutionary change, behavior and external factors of the physical and biological environment are more significant in determining the rate, direction, and nature of change over long periods of time."

But I found Robert Carroll less likely to be the Carroll in Carroll's Law that Bibleland speaks of.
Edited by - beskeptigal on 03/31/2006 12:36:04
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Bibleland
Skeptic Friend

USA
51 Posts

Posted - 03/31/2006 :  14:59:51   [Permalink]  Show Profile  Visit Bibleland's Homepage Send Bibleland a Private Message
I appreciate your input. Yes I'm YEC however I want to understand what your position is before I speak. And from what I have to chew on that could be some time. Please continue to post if you have more to contribute. I intently read every word.
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Dave W.
Info Junkie

USA
26022 Posts

Posted - 03/31/2006 :  15:05:46   [Permalink]  Show Profile  Visit Dave W.'s Homepage Send Dave W. a Private Message
quote:
Originally posted by beskeptigal

Evo Devo is evolution de-evolution...
Evo-Devo refers to the wedding of evolution with developmental biology, actually. Very interesting stuff.

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Dave W.
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USA
26022 Posts

Posted - 03/31/2006 :  20:14:15   [Permalink]  Show Profile  Visit Dave W.'s Homepage Send Dave W. a Private Message
Hiya, Bibleland!

Do you happen to have any ideas on when the Lost World Museum will begin to really fulfill its mission?

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filthy
SFN Die Hard

USA
14408 Posts

Posted - 04/01/2006 :  03:30:11   [Permalink]  Show Profile Send filthy a Private Message
Thanks, B'gal. I had the wrong Caroll, obviously. But he gave me the chance & the excuse to make the statement I wanted to put forth.

I would like to see that Lost World Museum. I am already planning a trip to Cincy, health permitting, to take in Ken Ham's show.




"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)

"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres


"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude

Brother Boot Knife of Warm Humanitarianism,

and Crypto-Communist!

Edited by - filthy on 04/01/2006 03:32:15
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Bibleland
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USA
51 Posts

Posted - 04/01/2006 :  07:04:15   [Permalink]  Show Profile  Visit Bibleland's Homepage Send Bibleland a Private Message
The Lost World Museum will begin its mission starting April locally (Syracuse, N.Y.). We will be showing some object that will help people understand the nature of mutations in their role of developing the race from Lucy till today. Matter of fact I have a piece of information I'm trying to see if it is true. Maybe you can help. In Marvin Lubenow's book Bones of Contention he states that evolutionists state that 5,000,000 mutations took place over 3,000,000 years to bring "Lucy" to where we are today. Anyone ever heard that number before? Is it less? Is it more?
We hope to open the museum in the late summer or fall of 06. The blog has been chronicling the events that lead up to present day on the how's and why's. www.lostworldmuseum.com If interested we just added a "subscribe to this blog" feature so everytime a new piece of the Museum's puzzle is placed you'll get informed as fast as the trilobite got his complex eye's in the cambrian explosion.
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beskeptigal
SFN Die Hard

USA
3834 Posts

Posted - 04/01/2006 :  11:34:25   [Permalink]  Show Profile Send beskeptigal a Private Message
quote:
Originally posted by Dave W.

quote:
Originally posted by beskeptigal

Evo Devo is evolution de-evolution...
Evo-Devo refers to the wedding of evolution with developmental biology, actually. Very interesting stuff.

Sorry, I read that stuff in a big hurry late at night. Thanks for the additional notes.
Edited by - beskeptigal on 04/01/2006 11:35:28
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beskeptigal
SFN Die Hard

USA
3834 Posts

Posted - 04/01/2006 :  13:15:50   [Permalink]  Show Profile Send beskeptigal a Private Message
quote:
Originally posted by Bibleland

The Lost World Museum will begin its mission starting April locally (Syracuse, N.Y.). We will be showing some object that will help people understand the nature of mutations in their role of developing the race from Lucy till today. Matter of fact I have a piece of information I'm trying to see if it is true. Maybe you can help. In Marvin Lubenow's book Bones of Contention he states that evolutionists state that 5,000,000 mutations took place over 3,000,000 years to bring "Lucy" to where we are today. Anyone ever heard that number before? Is it less? Is it more?
We hope to open the museum in the late summer or fall of 06. The blog has been chronicling the events that lead up to present day on the how's and why's. www.lostworldmuseum.com If interested we just added a "subscribe to this blog" feature so everytime a new piece of the Museum's puzzle is placed you'll get informed as fast as the trilobite got his complex eye's in the cambrian explosion.

If you are truly interested in the evidence and not just going to ignore it, you do indeed have a lot of work to do.

First, modern day humans are not directly descended from Lucy. Lucy is from a 'cousin' species, Australopithecus afarensis. The fossil's age is about 3.2 million years.

A chronology from there, based on current evidence, can be found on this site, Hominid Evolution from Australopithecus to Cro-Magnon.

You can also get a better picture from The Tree of Life website. The branch of Hominidae shows you where Lucy's species branches off.

**Note on the branch lines which show the tree diagram with two taxa, one on a non-monophyletic branch:
quote:
Branches that are a group of three lines rather than one solid bar indicate that the group is not monophyletic. Generally, we try to avoid non-monophyletic groups in the Tree of Life. However, we sometimes need to work with them, if we want to divide the diversity of a large group into manageable pieces in the absence of phylogenetic hypotheses. In the following tree, group A is non-monophyletic, indicating that Group B's closest relative is actually a subgroup of Group A, but we don't know which subgroup that is.


To date, 160,000-year-old fossilized skulls uncovered in Ethiopia are oldest anatomically modern humans.

As to recovered, DNA, in 1997, for the first time, DNA of a premodern human was recovered.

It was DNA from Neanderthal remains.
quote:
DNA Shows Neandertals Were Not Our Ancestors

Neandertals and modern humans diverged genetically 500,000 to 600,000 years ago, suggesting that though they may have lived at the same time, Neandertals did not contribute genetic material to modern humans.

the Neandertal sequence branches before the divergence of the various human mitochondrial DNA lineages, but after the split from chimpanzees.



Now with things in proper order the claim of how many mutations were needed can be better addressed. Those who would like to fit the evidence to the Bible instead of looking at the evidence and determining what it shows have come up with various reasons to disbelieve that the evidence is overwhelmingly in support of evolution as the correct theory of the origin of species. One of those 'reasons' has been to try to show that the number of mutations needed to get from the earliest life form to humans could not have occurred in the time it took for humans to evolve. So I assume that is where you are coming from.

It helps to actually look at the science of genetics rather than to make poorly informed speculations and oversimplified interpretations of the evidence. So to start with, there are approximately 3 billion base pairs of nucleic acids in the human genome. But from one human to another, ~3 million of those base pairs differ. So already the nonsense you have heard about how many changes are needed to get from Lucy to humans is clearly wrong.

We have no DNA from Lucy so one must infer from species we do have DNA to look at. We differ from each other by ~0.1% of our genetic material. We differ from chimpanzees, our closest living relatives, by about 2%. And we differ from Neanderthals by something in between. (I didn't bother to look it up but I'm sure the information is on the web somewhere.) However, you cannot draw a direct conclusion from this about how many mutations are needed to get from Lucy to modern humans because all three, chimps, Neanderthals and Lucy are not in a direct line with humans. We would have to extrapolate where each species did indeed have a common ancestor.

I'm not going to look for a specific number of mutations over time for you right now. I may look later. But you can see from what I have posted that the claims about not enough time for mutations are made by people who don't have a clue what they are talking about. And unfortunately, from there they pass the supposed argument on to the next person who believes it, but also doesn't have a clue what they are talking about.
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filthy
SFN Die Hard

USA
14408 Posts

Posted - 04/01/2006 :  13:57:08   [Permalink]  Show Profile Send filthy a Private Message
I would hesitate to use Bones of Contention for a reference. Whilst looking around for it at TO (I've heard of it but I am not familiar with it), I came across a few reviews.
quote:
Review: Bones of Contention
The book Bones of Contention, by Marvin Lubenow (1992), is considered by many creationists to be the definitive creationist treatment of the claimed evidence for human evolution. To his credit, Lubenow has read a large amount of the scientific literature on human evolution, and his book stands up well compared to the gross incompetence of other creationist authors such as Duane Gish and Malcolm Bowden who have written on the same topic. By any other standards, the book fails badly and will not convince anyone familiar with the details of the literature on human evolution.

The major theme of Bones of Contention is that the various species of hominid cannot form an evolutionary sequence because they overlap one another in time.

Another, concerning brain sizes, is here.
quote:
Figures for the average brain size of modern humans tend to vary between sources, but a typical value is 1350 or 1400 cc (cubic centimetres). The following figures should convey a feel for the normal range of variation in human skulls. Burenhult (1993) states that the 90% of humans fit in the range 1040-1595 cc, and that the extreme range is 900-2000 cc. S.J. Gould, in "The Mismeasure of Man", reviewed a 19th century study by Morton of 600 skulls which ranged from 950 to 1870 cc (and 25% of this sample was of small-statured Peruvians, so the figure of 950 cc is, if anything, lower than it might be for 600 randomly selected humans). Morton also catalogued his skulls by race, with the lowest average for any racial group being 1230 cc.

Various sources, some of them creationist, give lower limits for human brain size of 900 or 830 cc. The prominent British anatomist Sir Arthur Keith in 1948 gave 855 cc as the lowest known human brain volume (compared with 650 cc as the then highest known brain volume for a gorilla). Normal humans with even smaller brains have been found, but they are very rare. Microcephalics, who are subnormal in intelligence, can be as low as 600 cc, but this is a pathological condition and such skulls cannot be considered normal.

Interesting stuff...




"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)

"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres


"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude

Brother Boot Knife of Warm Humanitarianism,

and Crypto-Communist!

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