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Author Topic:   PROBLEM: Evolution is only a theory
Phobos
Inactive Member


Message 16 of 32 (110871)
05-27-2004 11:14 AM


In simple terms, a law is a mathematical description and a theory is an explanation.
The law of gravity lets you calculate how fast the apple falls from the tree.
The theory of gravity tells you the mechanism that makes it fall.
So, does the theory of evolution include any official laws? Perhaps laws of genetics? Or any statistical laws? Perhaps the first law of evolution is Change over Time >= 0.

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Loudmouth
Inactive Member


Message 17 of 32 (110889)
05-27-2004 12:34 PM
Reply to: Message 16 by Phobos
05-27-2004 11:14 AM


quote:
So, does the theory of evolution include any official laws?
The only thing approaching a law within evolution that I see has to do with natural selection. Not sure if the law has a name, but here it is nonetheless:
Law--Given variation within a population and limited resources, the variants best adapted at taking advantage of the limited resources will become the dominant variant within the population.
"Best adapted" is a very broad term, and can include several strategies. However, the logic of this "law" seems irrefutable.

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NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 18 of 32 (110985)
05-27-2004 9:11 PM
Reply to: Message 17 by Loudmouth
05-27-2004 12:34 PM


might have
I don't know enough to be sure, but I think there might be something that would have been called a "law" a couple of centuries ago. There are mathematical ,statistical descriptions of changes in populations and such. Aren't they "laws"?

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Syrus
Inactive Member


Message 19 of 32 (111328)
05-29-2004 12:56 AM
Reply to: Message 6 by Rrhain
05-09-2004 7:48 PM


This proves nothing
I am still amazed that there are people that believe that evolution is possible when we have so many bio-chemist pointing to the fact the bio-chemically it is impossible.
You give an example of bacteria. Did you run a DNA test on every single bacteria and compare the genetic structures or are you just guessing what might be causing the results you are looking at? Seems to me you are just guessing and trying to make the results fit based on a bias.
Lets take the examples of the millions of generations of fruit flies that have been studied year after year. Have biologists successfully mutated a single new species out of these fruit fly studies? Nope.
So lets equate the millions of generations of fruit flies that biologist can not get to form a new species to a pride of lions. If you cant make a single genetic mutation in a fruit fly after millions of generations, how can you expect anyone to believe the theory would affect a pride of lines to evolve into a lion with 6 legs that can run twice as fast?
Even if you could successfully mutate a fruit fly into a new species after a million generations, are you sure you have enough time to mutate a protozoa to a humpback whale in the projected age of the earth?
The reason evolution is not a law is because it does not work. If you want to say that a Galapagos parrots beak gets shorter after 30 generations because of lack of water...ok..but does that make it a different species? Will it ever be a different species? No.
Physics laws and chemical laws can be testes and re-tested hundreds of times with the same results within a standard deviation of error.
Biologist simply surmise what might happen and what could happen if these 23,574 variations all came together when a bolt of lightning struck a soup of amino acid chains.
Talk about a leap of faith.
Biology does provide a good service by developing better crop formulas and vaccines and the like, but evolution is as bad as religion...give it up.
Syrus

This message is a reply to:
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crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 20 of 32 (111349)
05-29-2004 3:25 AM
Reply to: Message 19 by Syrus
05-29-2004 12:56 AM


Seems to me you are just guessing and trying to make the results fit based on a bias.
If it seems that way to you, you didn't understand the experiment.
The virus destroys all but a few individuals, which then form a new population. There's only two explanations for why some individuals survived:
1) Bacteria possess an innate ability to resist this virus.
2) Certain individuals had a mutation that allowed them to resist the virus.
We know it can't be 1, because the bacteria are clones - they must be, that's a fact of how bacteria reproduce. If bacteria have an innate ability to resist this virus, they all would have. There would have been no visible effect when the virus was added.
We know therefore that 2 must have happened by process of elimination. Mutation is the only logical explanation for the resistance to the virus.
So lets equate the millions of generations of fruit flies that biologist can not get to form a new species
What the hell are you talking about? It's easy to get new fruit fly species in the lab, and it's been observed many times:
quote:
5.3 The Fruit Fly Literature
5.3.1 Drosophila paulistorum
Dobzhansky and Pavlovsky (1971) reported a speciation event that occurred in a laboratory culture of Drosophila paulistorum sometime between 1958 and 1963...
5.3.2 Disruptive Selection on Drosophila melanogaster
Thoday and Gibson (1962) established a population of Drosophila melanogaster from four gravid females...
5.3.3 Selection on Courtship Behavior in Drosophila melanogaster
Crossley (1974) was able to produce changes in mating behavior in two mutant strains of D. melanogaster...
5.3.4 Sexual Isolation as a Byproduct of Adaptation to Environmental Conditions in Drosophila melanogaster
Kilias, et al. (1980) exposed D. melanogaster populations to different temperature and humidity regimes for several years. They performed mating tests to check for reproductive isolation. They found some sterility in crosses among populations raised under different conditions...
5.3.5 Sympatric Speciation in Drosophila melanogaster
In a series of papers (Rice 1985, Rice and Salt 1988 and Rice and Salt 1990) Rice and Salt presented experimental evidence for the possibility of sympatric speciation...
5.3.6 Isolation Produced as an Incidental Effect of Selection on several Drosophila species
In a series of experiments, del Solar (1966) derived positively and negatively geotactic and phototactic strains of D. pseudoobscura from the same population by running the flies through mazes...
5.3.7 Selection for Reinforcement in Drosophila melanogaster
Some proposed models of speciation rely on a process called reinforcement to complete the speciation process. Reinforcement occurs when to partially isolated allopatric populations come into contact. Lower relative fitness of hybrids between the two populations results in increased selection for isolating mechanisms...
5.3.8 Tests of the Founder-flush Speciation Hypothesis Using Drosophila
The founder-flush (a.k.a. flush-crash) hypothesis posits that genetic drift and founder effects play a major role in speciation (Powell 1978)... Dodd and Powell (1985) tested this hypothesis using D. pseudoobscura... Forty-four months after the start of the experiment (and fifteen months after the last flush) the populations were again tested. Once again, no postmating isolation was seen. Three populations showed behavioral isolation in the form of positive assortative mating.
from Observed Instances of Speciation
As you can see, it's almost trivial to cause speciation in fruit flies.
but does that make it a different species? Will it ever be a different species? No.
Oh, I see. You don't know what the word "species" means. Why didn't you just say so instead of looking like an idiot?
Here's the most useful definition, from the same link:
quote:
Over the last few decades the theoretically preeminent species definition has been the biological species concept (BSC). This concept defines a species as a reproductive community.
Dobzhansky defined a species as
"... that stage of evolutionary progress at which the once actually or potentially interbreeding array of forms becomes segregated into two or more separate arrays which are physiologically incapable of interbreeding." (Dobzhansky 1937)
So, in fact, not only are new species possible, they're quite common, as are mutations. You yourself have somewhere between 5 and 50.
Physics laws and chemical laws can be testes and re-tested hundreds of times with the same results within a standard deviation of error.
And speciation can be stimulated to the same degree of repeatability and accuracy. The mechanisms are quite well-understood in most cases.
Biology does provide a good service by developing better crop formulas and vaccines and the like, but evolution is as bad as religion..
What you seem to be ignorant of is the fact that biologists use evolutionary theory to create those crops and vaccines. That's the greatest testament to the accuracy of the evolutionary model. Religion? Not by any definition of religion I'm aware of.

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Replies to this message:
 Message 21 by custard, posted 05-29-2004 3:59 AM crashfrog has replied

  
custard
Inactive Member


Message 21 of 32 (111351)
05-29-2004 3:59 AM
Reply to: Message 20 by crashfrog
05-29-2004 3:25 AM


CF explains:
2) Certain individuals had a mutation that allowed them to resist the virus.
We know it can't be 1, because the bacteria are clones
Wow, I read the original experiment, but it never really sunk in and now I'm full of questions. I'm completely out of my element here, so these are honest questions.
So organisms that are reproduced from a parent without fertilization, like bacteria, are considered clones but they are still capable of mutating? (I'm having difficulty phrasing this - sorry)
My understanding of a clone has always been that it was an exact replica of the original. Is this just some movie biology that I've accepted as real; and are the offspring of all organisms that clone themselves capable of mutating from the parent?
How does this differ from creatures such as worms or starfish, which if cut in half, can actually grow into two seperate organisms?
Also Aspen groves, which I believe are clones of the parent organism, is it possible that some of the individual trees in the grove have mutated from the parent?
This is heady stuff. I appreciate any answers, or links, you may be able to provide.

This message is a reply to:
 Message 20 by crashfrog, posted 05-29-2004 3:25 AM crashfrog has replied

Replies to this message:
 Message 22 by crashfrog, posted 05-29-2004 4:06 AM custard has replied

  
crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 22 of 32 (111352)
05-29-2004 4:06 AM
Reply to: Message 21 by custard
05-29-2004 3:59 AM


So organisms that are reproduced from a parent without fertilization, like bacteria, are considered clones but they are still capable of mutating?
Well, I used "clones" in a loose sense of the term. If they were always clones, obviously evolution couldn't occur.
But to as large an extent as possible, bacteria reproduce clonally. They only process besides mutation that introduced variety is the genetic exchange that most bacteria engage in sometimes.
Is this just some movie biology that I've accepted as real; and are the offspring of all organisms that clone themselves capable of mutating from the parent?
I'm not sure if "clone" refers to an exact copy, or just as exact a copy as possible. Theoretically all your somatic cells are supposed to be clones of each other, but obviously each of your cells is likely to have mutations caused by chemical or radioactive damage.
Also Aspen groves, which I believe are clones of the parent organism, is it possible that some of the individual trees in the grove have mutated from the parent?
Mutations are always possible. If the practical definition of "clone" doesn't allow for mutation then I suspect no organism could ever be referred to as a clone. I think that when biologists call something a clone, they're referring to reproduction that doesn't allow for the genetic shuffling of obligate sexuality, which as I understand it is the primary source of variety in sexual species.
This message has been edited by crashfrog, 05-29-2004 03:07 AM

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 Message 23 by custard, posted 05-29-2004 4:39 AM crashfrog has replied

  
custard
Inactive Member


Message 23 of 32 (111355)
05-29-2004 4:39 AM
Reply to: Message 22 by crashfrog
05-29-2004 4:06 AM


I think that when biologists call something a clone, they're referring to reproduction that doesn't allow for the genetic shuffling of obligate sexuality,
So the sheep Dolly, for example, would she be an exact replica of her parent organism? Or could she have mutations that distinguish her from the parent?
This is interesting stuff. I'm going to have to do more research; and thanks for the answers so far.

This message is a reply to:
 Message 22 by crashfrog, posted 05-29-2004 4:06 AM crashfrog has replied

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 Message 24 by crashfrog, posted 05-29-2004 4:59 AM custard has replied

  
crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 24 of 32 (111359)
05-29-2004 4:59 AM
Reply to: Message 23 by custard
05-29-2004 4:39 AM


So the sheep Dolly, for example, would she be an exact replica of her parent organism? Or could she have mutations that distinguish her from the parent?
Presumably she has a few mutations; DNA replication is usually errorless but in an entire animal's worth of cells we would expect a number of mutations.
If you wanted to be absolutely pedantic about it, Dolly is an exact replica of her mom except for:
1) Whatever mutations were present in the mother's somatic cell from which Dolly's genetic material was extracted;
2) Dolly's mtDNA, which were inherent to the zygote who's nucleus was replaced with the above;
3) Any mutations accrued in Dolly's somatic cells through the course of her life (though we usually ignore these as they aren't passed on to offspring);
4) Any epigenetic factors - things like coat pigmentation or structure of the iris, or more general things like exact height and weight, which are more environmentally influenced than genetic.
This is interesting stuff.
Yeah, it's neat. There's a lot of mutation going on that simply isn't that relevant to evolution; for instance mutations that don't happen in germ cells (and therefore aren't usually passed on) or mutations that simply have no effect due to being on non-coding sequences or that, through redundancy, wind up coding for the same protien as before.
Actually maybe I shouldn't say it isn't relevant; it's just that these mutations rarely, if ever, have any effect on the selective fitness of the organism, and so they generally slide into the background of our consideration, you know?
This message has been edited by crashfrog, 05-29-2004 04:01 AM

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Replies to this message:
 Message 25 by custard, posted 05-29-2004 5:07 AM crashfrog has replied
 Message 28 by Wounded King, posted 06-01-2004 7:49 AM crashfrog has replied

  
custard
Inactive Member


Message 25 of 32 (111361)
05-29-2004 5:07 AM
Reply to: Message 24 by crashfrog
05-29-2004 4:59 AM


Thanks, that's awesome
So how the hell do people have such a hard time not believing in evolution? Amazing.
This message has been edited by custard, 05-29-2004 04:08 AM

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crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 26 of 32 (111364)
05-29-2004 5:19 AM
Reply to: Message 25 by custard
05-29-2004 5:07 AM


So how the hell do people have such a hard time not believing in evolution?
I'm an ex-creationist, so I'll try and share what the deal was with me:
For one thing, I was a teenager, and I suspect you've noticed that that's true of a lot of YEC's here. It's attractive to think that you have a kind of secret knowledge about the universe - something that only you and a select few seem to know. The fact that the vast, vast majority of scientists disagree with creationism makes it all the more attractive to some young folks.
Also the species thing confused me. I never understood until much, much later how they got around the "hopeful monster" problem - if a species is defined as a reproductive community, then the first individual of a new species is going to be SOL because there's nobody else he can reproduce, right?
Well, wrong, obviously, but it took me a while to learn to look at the problem from the aspect of population genetics and not individual physiology. Honestly if you asked me for advice about a high school biology curriculum, I'd start with population genetics and Mendel's experiments (the high-level behavior of heredity) before delving into the world of the cell (the actual mechanisms of heredity.) I think the way we teach biology is one of the greatest barriers to the understanding of evolution by laypeople.
But I agree with your sentiment. Once you understand it, evolution is almost so simple that it just has to be accurate. So elegant.

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 Message 27 by jar, posted 05-29-2004 12:15 PM crashfrog has not replied

  
jar
Member (Idle past 393 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 27 of 32 (111454)
05-29-2004 12:15 PM
Reply to: Message 26 by crashfrog
05-29-2004 5:19 AM


crashfrog writes:
I think the way we teach biology is one of the greatest barriers to the understanding of evolution by laypeople.
Too true and applicable to almost any subject.
I might even change that to read...
I think the way we teach the Bible is one of the greatest barriers to the understanding of religion by laypeople.

Aslan is not a Tame Lion

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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 28 of 32 (111998)
06-01-2004 7:49 AM
Reply to: Message 24 by crashfrog
05-29-2004 4:59 AM


You left out a number of changes which are arguably not somatic mutations such as the shortening of telomeres and epigenetic factors of a molecular biological nature such as DNA methylation which are known to be disturbed in many cloned animals and which can affect the gene expression patterns of the cloned individual.
TTFN,
WK

This message is a reply to:
 Message 24 by crashfrog, posted 05-29-2004 4:59 AM crashfrog has replied

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 Message 29 by crashfrog, posted 06-01-2004 8:14 AM Wounded King has replied

  
crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 29 of 32 (112002)
06-01-2004 8:14 AM
Reply to: Message 28 by Wounded King
06-01-2004 7:49 AM


You don't think shortened telomeres count as a kind of somatic mutation? If by "mutation" we mean "genetic change", it would seem to apply. Then again I supppose it's not a mutation in the traditional sense, right? Bah - never mind, I hate talking about what words mean.
You're right, though, I had forgot about those. I had hoped by mentioning somatic genetic changes, I had covered all the bases, but apparently not.
This message has been edited by crashfrog, 06-01-2004 07:14 AM

This message is a reply to:
 Message 28 by Wounded King, posted 06-01-2004 7:49 AM Wounded King has replied

Replies to this message:
 Message 30 by Wounded King, posted 06-01-2004 1:03 PM crashfrog has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 30 of 32 (112071)
06-01-2004 1:03 PM
Reply to: Message 29 by crashfrog
06-01-2004 8:14 AM


OK, I'll give you telomere shortening as an arguable case of a primary sequence deletion and therefore classically genetic mutation, but the same doesn't work for methylation, or inheritable histone modifications.
TTFN,
WK

This message is a reply to:
 Message 29 by crashfrog, posted 06-01-2004 8:14 AM crashfrog has replied

Replies to this message:
 Message 31 by crashfrog, posted 06-02-2004 12:35 PM Wounded King has not replied

  
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