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Author Topic:   Problems w/ the Current ToE
Thmsberry
Inactive Member


Message 1 of 13 (234)
03-14-2001 9:50 PM


Percy,
Thanks. I must admit even after knowing where to look, it still took a while for me to notice the link.

Problems with the Current ToE.

The current ToE has a paradox in it. The talkorigin links What is Evolution and What is the Modern Synthesis will be used. It quotes Futyama that "Biological evolution ... is change in the properties of populations of organisms that transcend the lifetime of a single individual. The ontogeny of an individual is not considered evolution; individual organisms do not evolve. "
Yet at the theories core sits the Darwinian assumption that "The changes in populations that are considered evolutionary are those that are inheritable via the genetic material from one generation to the next. Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportion of different alleles within a population (such as those determining blood types) to the successive alterations that led from the earliest protoorganism to snails, bees, giraffes, and dandelions."
Yet, Larry Moran writes, "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..."
I hope you can see the contradiction. Current ToE claims that evolution does not occur at the level of an individual and organism, but at the level of populations, genes, and phenotypes. It claims that it has made a major paradigm shift from Darwinism's concerns at the individual and organism level. Then, the same theory turns around and assumes that all biodiverstiy can be traced back to an individual live organism. Yet, Evolution of today, unlike in Darwinism, does not occur at the level of an individual organism. So the idea of an individual live organism evolving and producing the variety of life we have today is not possible within this major paradigm shift. Paradox


Replies to this message:
 Message 2 by lbhandli, posted 03-14-2001 11:57 PM Thmsberry has responded

lbhandli
Inactive Member


Message 2 of 13 (235)
03-14-2001 11:57 PM
Reply to: Message 1 by Thmsberry
03-14-2001 9:50 PM


1) there is a debate over whether or not there is a single universal ancestor or several ancestors so the line in Futuyma is a bit presumptuous. Of course it is several years old and well before Doolittle's work.

2) The only challenge you present here is that a single ancestor doesn't fit this definition. If there was a single ancestor as soon as it reproduced a population took over and we have consistency.

Cheers,
Larry Handli


This message is a reply to:
 Message 1 by Thmsberry, posted 03-14-2001 9:50 PM Thmsberry has responded

Replies to this message:
 Message 3 by Thmsberry, posted 03-15-2001 6:04 AM lbhandli has responded

Thmsberry
Inactive Member


Message 3 of 13 (238)
03-15-2001 6:04 AM
Reply to: Message 2 by lbhandli
03-14-2001 11:57 PM


Larry,

You wrote:
"1) there is a debate over whether or not there is a single universal ancestor or several ancestors so the line in Futuyma is a bit presumptuous. Of course it is several years old and well before Doolittle's work.
2) The only challenge you present here is that a single ancestor doesn't fit this definition. If there was a single ancestor as soon as it reproduced a population took over and we have consistency."

First, this brings up a couple of questions.

If you believe that only one live organism was the ancestor of all life, what type of scientific evidence can possibly support this conclusion?

If you accept the view of several live ancestors, what is the proposed genetic variation amongst these live ancestors?

I have read that those who support several live ancestors make the assumption that they are all members of the same species. Yet, all current evidence points to the fact that the oldest known live organisms on this planet reproduce asexually. In addition, all current evidence points to the fact that the oldest known live organisms were without a nucleus. Doesn't these scientific facts make the idea that they were all of the same species ridiculously ambiguous and basically meaningless and unprovable?

Asexual organisms alone have an ambiguous species definition. Add to that the fact that Archae show no consistent correlations between morphology and known phylogeny and their phylogenies even intersect with organisms of other domains. Thus, How would it ever even be possible to determine if the early live ancestors(as in a population) were of the same species?


This message is a reply to:
 Message 2 by lbhandli, posted 03-14-2001 11:57 PM lbhandli has responded

Replies to this message:
 Message 4 by lbhandli, posted 03-15-2001 1:45 PM Thmsberry has responded
 Message 7 by Percy, posted 03-16-2001 11:16 AM Thmsberry has responded

lbhandli
Inactive Member


Message 4 of 13 (240)
03-15-2001 1:45 PM
Reply to: Message 3 by Thmsberry
03-15-2001 6:04 AM


quote:
Originally posted by Thmsberry:

If you believe that only one live organism was the ancestor of all life, what type of scientific evidence can possibly support this conclusion?


The only manner this could be confirmed is through a genetic marker or something. I doubt that is possible.

quote:

If you accept the view of several live ancestors, what is the proposed genetic variation amongst these live ancestors?

I'd reference you to Doolittle's article in Scientific American and his cited works there. This is a bit beyond me.

quote:

I have read that those who support several live ancestors make the assumption that they are all members of the same species. Yet, all current evidence points to the fact that the oldest known live organisms on this planet reproduce asexually. In addition, all current evidence points to the fact that the oldest known live organisms were without a nucleus. Doesn't these scientific facts make the idea that they were all of the same species ridiculously ambiguous and basically meaningless and unprovable?

If they were virtually identical, not really. Given no genetic evidence you would have to rely on morphology and you wouldn't be using the reproduction standard. Again, I'm not sure why this is a particular problem. Labeling them the same species or not seems to be more of a semantic argument given the probably state of the Earth at the time.

Larry


This message is a reply to:
 Message 3 by Thmsberry, posted 03-15-2001 6:04 AM Thmsberry has responded

Replies to this message:
 Message 5 by Thmsberry, posted 03-15-2001 3:59 PM lbhandli has responded

Thmsberry
Inactive Member


Message 5 of 13 (241)
03-15-2001 3:59 PM
Reply to: Message 4 by lbhandli
03-15-2001 1:45 PM


You wrote:
"If they were virtually identical, not really. Given no genetic evidence you would have to rely on morphology and you wouldn't be using the reproduction standard."

Morphological similarity amongst organisms in the domain of known Archae does not correlate to a species level of differentiation. They relate more to the phylum level. And for the oldest Kingdom Archae, considered to be the closest known thing to this common ancestor it is currently impossible to even test its morphology.

You wrote:"Again, I'm not sure why this is a particular problem. Labeling them the same species or not seems to be more of a semantic argument given the probably state of the Earth at the time. "

If the first population of life contained multiple kingdoms. Such as the diversity in Archae and Eubacteria currently shows. and If this diversity does not fit in a nested hierarchy that corelates to the genetic diversity. As the diversity in the Archae and Eubacteria currently shows. Then the first population was not one species. It wasn't even monophyletic.

This would make the assumption of this population stemming from one live ancestor contrary to the actual evidence.

It would also make the idea of all life coming from a single ancestor or single species meaningless. Because Phyletic genetic differences in EuBacteria and Archae are greater than the entire range of genetic difference between the Plant and Animal kingdom.

And considering that we are including horizontal mechanisms.

This basically leaves the premise that all life on this planet can be traced in part to a population of a single domain.

Thus, the individual organism and/or species idea is not a supported one. And this is one of the major aspects of the current ToE.


This message is a reply to:
 Message 4 by lbhandli, posted 03-15-2001 1:45 PM lbhandli has responded

Replies to this message:
 Message 6 by lbhandli, posted 03-15-2001 7:23 PM Thmsberry has not yet responded

lbhandli
Inactive Member


Message 6 of 13 (242)
03-15-2001 7:23 PM
Reply to: Message 5 by Thmsberry
03-15-2001 3:59 PM


quote:

Morphological similarity amongst organisms in the domain of known Archae does not correlate to a species level of differentiation. They relate more to the phylum level. And for the oldest Kingdom Archae, considered to be the closest known thing to this common ancestor it is currently impossible to even test its morphology.

This is not a settled issue. Indeed, recent arguments are disputing that that Archea evolved from eukaryotic root due to high genetic similarities inferred from complete genome analysis between Archaebacteria and Eubacteria inferred from complete genome analysis. . See:Hervé Philippe, Patrick Forterre. The Rooting of the Universal Tree of Life Is Not Reliable. Journal Of Molecular Evolution. 49, 509 (1999). They argue for a eukaryotic ancestor and provide several reasons why. They specifically take issue with previous attempts to create a tree of life

[QUOTE][b]
Furthermore, the addition of new sequences to data sets has often turned apparently reasonable phylogenies into confused ones. We have thus revisited all composite protein trees that have been used to root the universal tree of life up to now (elongation factors, ATPases, tRNA synthetases, carbamoyl phosphate synthetases, signal recognition particle proteins) with updated data sets. In general, the two prokaryotic domains were not monophyletic with several aberrant groupings at different levels of the tree. Furthermore, the respective phylogenies contradicted each others, so that various ad hoc scenarios (paralogy or lateral gene transfer) must be proposed in order to obtain the traditional Archaebacteria-Eukaryota sisterhood. More importantly, all of the markers are heavily saturated with respect to amino acid substitutions. As phylogenies inferred from saturated data sets are extremely sensitive to differences in evolutionary rates, present phylogenies used to root the universal tree of life could be biased by the phenomenon of long branch attraction.
[/QUOTE]

[/b]

You may access some of the work done in the area at a conference that addresses many of these issues at: LesTreilles_e.

The essential reasons for inferring a single common ancestor whether several of one species one organism comes from the observations:

http://www.mines.unr.edu/able/GEOL100-11/tsld010.htm
Taken from a lower level course, but a nice summary is there.

Could the inference be wrong? Sure, but given the uncertainty of the actual tree of life and those 5 factors, it is still a quite viable hypothesis. At most, even if it is wrong, evolution still holds back a couple billion years.

[This message has been edited by Percipient (edited 03-19-2001).]


This message is a reply to:
 Message 5 by Thmsberry, posted 03-15-2001 3:59 PM Thmsberry has not yet responded

Percy
Member
Posts: 18476
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.8


Message 7 of 13 (243)
03-16-2001 11:16 AM
Reply to: Message 3 by Thmsberry
03-15-2001 6:04 AM


Hi Thmsberry,

quote:

I have read that those who support several live ancestors make the assumption that they are all members of the same species. Yet, all current evidence points to the fact that the oldest known live organisms on this planet reproduce asexually. In addition, all current evidence points to the fact that the oldest known live organisms were without a nucleus. Doesn't these scientific facts make the idea that they were all of the same species ridiculously ambiguous and basically meaningless and unprovable?


You've stated things a bit unequivocally ("all current evidence etc...").

First, they're not scientific facts but informed hypotheses.

Second, in the general case, members of the same species can be assumed to have a common ancestor. When this is not the case it means the same species evolved more than once. This is probably only possible in any meaningful sense for single-celled organisms, and all it would mean is that the same or very similar genetic accidents happened more than once, resulting in organisms with equivalent genomes. I'm speculating, since I've never myself read of anyone seriously entertaining this possibility, but that doesn't mean anything.

One of the views receiving attention these days is that gene sharing was very common among early life, and this is described in some detail in an article (that I referenced once before, and I see Larry mentions it, too) titled Uprooting the Tree of Life by W. Ford Doolittle that appeared in the February, 2000, issue of Scientific American, and here's a diagram from that article (click to enlarge):

We've already discussed that BSC is mostly appropriate only for the more complex lifeforms like mammals, and so it certainly shouldn't be applied to a situation like that represented above involving single-celled organisms. Species distinctions can be more difficult to make when organisms are single-celled and similar, but the DNA tells the truth. We can certainly make no specific species distinctions about postulated evolutionary ancestors, but the above diagram derives from DNA analysis of modern organisms. It is speculative, and if that's a synonym for "ridiculously ambiguous" then fine. It's certainly also unprovable, as is all science, but it does have evidentiary support based on DNA and so definitely is not "basically meaningless."

quote:

Asexual organisms alone have an ambiguous species definition. Add to that the fact that Archae show no consistent correlations between morphology and known phylogeny and their phylogenies even intersect with organisms of other domains. Thus, How would it ever even be possible to determine if the early live ancestors(as in a population) were of the same species?


I think you mistake what is being attempted. It is understood that we can't know what the specific ancestors were, but we can certainly draw hypotheses concerning possible scenarios. Current work is identifying and characterizing the reasonable possibilities indicated by the evidence available, that is all. But it is understood that there can never be any definitive evolutionary tree because there is simply insufficient evidence. Time has destroyed most of the evidence, and scientists just have to make do with what's left.

quote:

If the first population of life contained multiple kingdoms. Such as the diversity in Archae and Eubacteria currently shows. and If this diversity does not fit in a nested hierarchy that corelates to the genetic diversity. As the diversity in the Archae and Eubacteria currently shows. Then the first population was not one species. It wasn't even monophyletic.


By the time you wrote this Larry had already referenced you to Doolittle. It is already well understood that early life might not fit a neatly nested hierarchy.

quote:

This basically leaves the premise that all life on this planet can be traced in part to a population of a single domain.

Thus, the individual organism and/or species idea is not a supported one. And this is one of the major aspects of the current ToE.


The ToE is just a framework of understanding that unites Darwinian concepts like descent with modification and natural selection with a genetic foundation. The ToE never axiomatically held that all life descends from a single original cell. That's just a once-common perspective that fit within the framework of the theory, as do the newer perspectives on this topic. It was not a major aspect of the theory, but rather just a possibility permitted within the framework of the theory.

The possibility of all modern life descending from a single cell is consistent with the ToE. So is the possibility of all modern life descending from a community of gene-sharing cells. Changing preferences within the scientific community for one over the other do not require any change to the encompassing theory.

--Percy


This message is a reply to:
 Message 3 by Thmsberry, posted 03-15-2001 6:04 AM Thmsberry has responded

Replies to this message:
 Message 8 by Thmsberry, posted 03-16-2001 12:39 PM Percy has responded

  
Thmsberry
Inactive Member


Message 8 of 13 (244)
03-16-2001 12:39 PM
Reply to: Message 7 by Percy
03-16-2001 11:16 AM


Percy,

You wrote:"The ToE is just a framework of understanding that unites Darwinian concepts like descent with modification and natural selection with a genetic foundation. The ToE never axiomatically held that all life descends from a single original cell. That's just a once-common perspective that fit within the framework of the theory, as do the newer perspectives on this topic. It was not a major aspect of the theory, but rather just a possibility permitted within the framework of the theory.

The possibility of all modern life descending from a single cell is consistent with the ToE. So is the possibility of all modern life descending from a community of gene-sharing cells. Changing preferences within the scientific community for one over the other do not require any change to the encompassing theory."

The problem that I appear to be having is that you and Larry appear to be aware of the same info that I am on the topic.

You appear to follow and agree with my argument.

But then you end with the typical Darwinian rhetoric that it is possible that all life stemmed from one ancestral cell.

I have listed quotes in my previous post. Most of the Biological text that I have ever read on the topic and even the Talkorigin link make the claim that all biodiversity can be traced to a single live organism. They claim the current ToE explains biodiversity all the way back to this single live organism. So how can you make the claim that it is not a major aspect of the theory. At the very least, you must admit that it is always presented as a major aspect of the theory and no alternative possibility is usually mentioned.

Can you list some popular reputable textbook that states that all life emerged from a paraphyletic community of gene sharing cells? A possibility that is more consistent with the actual evidence.

Is single cell ancestry possible? Yes, in the same way almost anything is possible with a dearth of evidence. But it is simply not the most likely scenario given the same information that we both seem to be aware of.

If you in fact think single live ancestor is more likely, can you or Larry explain to me what I am missing? Because it appears to me that the evidence points in one direction, yet ToE currently presents an alternate possibility as the only one mostly because it more closely resembles Darwin's original argument.


This message is a reply to:
 Message 7 by Percy, posted 03-16-2001 11:16 AM Percy has responded

Replies to this message:
 Message 9 by lbhandli, posted 03-16-2001 2:56 PM Thmsberry has not yet responded
 Message 10 by Percy, posted 03-16-2001 3:20 PM Thmsberry has responded

lbhandli
Inactive Member


Message 9 of 13 (245)
03-16-2001 2:56 PM
Reply to: Message 8 by Thmsberry
03-16-2001 12:39 PM


from thmsberry:
quote:

Can you list some popular reputable textbook that states that all life emerged from a paraphyletic community of gene sharing cells? A possibility that is more consistent with the actual evidence.

The Doolittle reference specifically does says it is possible. And it is based on articles like the one I cited in my last message as well as other articles by Ford W. Doolittle. Additionally, it seems making as strong of a claim as you want would be making the same mistake your cited source does except in reverse.

Many texts may say exactly what you are saying they do and they are overstating the claim if they do. I don't believe that Futuyma takes a strong position in his book one way or another (meaning I could have missed it somewhere) but he certainly doesn't hold it as a central element as you claim the ToE does universally. Secondly, texts aren't always the best source for accurate and especially up to date information. Researchers are often at odds with texts because texts aren't updated frequently enough or are just inaccurate. In this case, you have been offered specific citations from recent research. Essentially, your argument would boil down to a lot of texts are bad. I agree, and as I review texts in social science quite freqently, this is only the tip of the iceberg.

Talkorigins.org certainly oversimplifies the issue in certain FAQs and several on talk.origins have complained about that. The problem is all writers are volunteers and don't have time to constantly update it. I'll mention it on talk.origins next time the issue comes up.

Larry


This message is a reply to:
 Message 8 by Thmsberry, posted 03-16-2001 12:39 PM Thmsberry has not yet responded

Percy
Member
Posts: 18476
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.8


Message 10 of 13 (246)
03-16-2001 3:20 PM
Reply to: Message 8 by Thmsberry
03-16-2001 12:39 PM


Hi Thmsberry,

quote:

But then you end with the typical Darwinian rhetoric that it is possible that all life stemmed from one ancestral cell.


I'm sorry if I wasn't clear. This isn't true. My views are strongly influenced by what I read. I found Doolittle's article in the February, 2000, issue of Scientific American, a diagram from which is included in my previous post, very persuasive. All that means is that given the information I'm aware of today, his is the explanation I find most acceptable. I consider his explanation tentative and subject to future revision and even refutation.

You are confusing specific perspectives within the ToE with the ToE itself. We just discussed the definition of the Modern Synthesis in detail in another thread. Both a single-cell origin and a multi-cell gene-sharing origin for modern life fit within the ToE. Your view seems to be that if a perspective is described in most books available today that it makes that view somehow fundamental to the theory. It doesn't. It just means it is, or was, a widely held view, nothing more.

quote:

Can you list some popular reputable textbook that states that all life emerged from a paraphyletic community of gene sharing cells? A possibility that is more consistent with the actual evidence.


What would it prove if I could or couldn't? You've already been given two references to articles representing that modern life may have originated from a community of gene-sharing cells. I don't know if the authors of these articles have written "popular reputable textbooks", but what does it matter given the references you already have? Reputable scientists are seriously exploring polyphyletic possibilities. Just the fact that you know about these possibilities means that you've read about them somewhere, so you of course know of other sources of this information than the ones we've given you. What do you care whether these views have yet made it into textbooks?

As it happens, Evolution, Third Edition (by Monroe W. Strickberger, 2000, Jones and Bartlett) not only mentions just such a possible scenario, but even has a diagram of a possible scenario for symbiotic evolution on page 181 (click to enlarge):

--Percy

[This message has been edited by Percipient (edited 03-16-2001).]


This message is a reply to:
 Message 8 by Thmsberry, posted 03-16-2001 12:39 PM Thmsberry has responded

Replies to this message:
 Message 11 by Thmsberry, posted 03-17-2001 3:48 AM Percy has responded

  
Thmsberry
Inactive Member


Message 11 of 13 (249)
03-17-2001 3:48 AM
Reply to: Message 10 by Percy
03-16-2001 3:20 PM


Percy and Larry,

Thanks for your arguments. It seems like you both actually lean toward the perspective I do. It was that apparent when Larry and I were debating live organism in a different thread. But I can see it now. And Percy thanks for the textbook reference.

However, I do not think that you see what paradoxes this perspective makes for the theory.

The current ToE is suppose to be an explanation for the Biodiversity on this planet. Yet a paraphyletic community of sharing cells model has life already starting with Biodiversity, so the theory can no longer be seen as an explantation for life's biodiversity. It becomes a partial explanation at best.

Also, the older the population of organisms that scientist examine the greater their biodiversity. Which would indicate that the greatest amount of biodiversity occurs the closer you get to the ancestral paraphyletic community. So while life is indeed changing over time. The greatest type of diversity existed in the initial community, and thus life has not become increasingly diverse. Another premise of the current ToE.

In addition, accepting horizontal mechanisms does not allow for the idea that commononality in organismal genomes indicate a live ancestral relationships. A paraphyletic community of sharing cells do not share a common live ancestor. They share a common dead ancestor, namely common DNA or RNA sequences.

The true explanation of life's biodiversity appears to occur at some sort of stage of symbiosis between a community of Prebionts. This would explain why a community of paryphyletic cells would have emerged in the first place. A stage that is extemely speculative and the current ToE by definition can never examine.

I await your responses to this post because this perspective means that the Current ToE can never fully explain life's biodiversity (Yet, it seeks to do just that), the premise that evolution has promoted increasing diversity is wrong, the idea of live ancestral relationships is only occasionally accurate. Pretty much leaving that the only implication of the theory is the minor observation that the Current ToE demonstrates that life varies over time.


This message is a reply to:
 Message 10 by Percy, posted 03-16-2001 3:20 PM Percy has responded

Replies to this message:
 Message 12 by Percy, posted 03-17-2001 10:30 AM Thmsberry has not yet responded
 Message 13 by Delvo, posted 05-21-2001 12:01 AM Thmsberry has not yet responded

Percy
Member
Posts: 18476
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.8


Message 12 of 13 (250)
03-17-2001 10:30 AM
Reply to: Message 11 by Thmsberry
03-17-2001 3:48 AM


Hi Thmsberry,

quote:

The current ToE is suppose to be an explanation for the Biodiversity on this planet. Yet a paraphyletic community of sharing cells model has life already starting with Biodiversity, so the theory can no longer be seen as an explantation for life's biodiversity. It becomes a partial explanation at best.


You seem determined to maintain the most odd view of theories I've ever encountered. Theories are never complete, and all theories are partial, simply because of the principle of tentativity. Scientists work to extend and expand theories. Sometimes a theoretical framework can't accommodate new discoveries, and then a new theory must be developed to replace the old.

I don't want to argue whether you're right or wrong about the ToE providing an incomplete explanation for biodiversity. As you trace further and further back in time you get more and more out of the realm of the ToE and into issues related to the origin of life. There are no hard and fast rules for drawing the boundary between these two areas.

If you decide that this particular point in the history of life belongs within the ToE, and that the ToE doesn't provide a satisfactory explanation for it, then that does mean the ToE is incomplete, but only in the sense I mentioned above that all theories are incomplete.

quote:

Also, the older the population of organisms that scientist examine the greater their biodiversity. Which would indicate that the greatest amount of biodiversity occurs the closer you get to the ancestral paraphyletic community. So while life is indeed changing over time. The greatest type of diversity existed in the initial community, and thus life has not become increasingly diverse. Another premise of the current ToE.


I'm sure this isn't true. For one thing, there are more species alive today on the planet than at any time in its history.

quote:

In addition, accepting horizontal mechanisms does not allow for the idea that commonality in organismal genomes indicate a live ancestral relationships. A paraphyletic community of sharing cells do not share a common live ancestor. They share a common dead ancestor, namely common DNA or RNA sequences.


The ToE includes genetic mechanisms, and so is inclusive of explanations concerning ancestral relationships based upon DNA/RNA sharing.

quote:

The true explanation of life's biodiversity appears to occur at some sort of stage of symbiosis between a community of Prebionts. This would explain why a community of paryphyletic cells would have emerged in the first place. A stage that is extemely speculative and the current ToE by definition can never examine.


But you have an odd definition of the ToE, one that not only isn't shared by others here, but also not by scientists working in this area, since they seem to believe they're operating within the framework of the ToE. It would make things a lot easier if you would accept the definitions the scientific community agrees upon.

I don't know if this helps, but from where I sit it looks like you're telling everyone else that if they squint and look sideways things will look the same to us as they do to you. No one but you sees any reason to do this.

--Percy


This message is a reply to:
 Message 11 by Thmsberry, posted 03-17-2001 3:48 AM Thmsberry has not yet responded

  
Delvo
Inactive Member


Message 13 of 13 (255)
05-21-2001 12:01 AM
Reply to: Message 11 by Thmsberry
03-17-2001 3:48 AM


quote:
The current ToE is suppose to be an explanation for the Biodiversity on this planet.

Not really. It's an explanation of a mechanism by which an observed process occurs. One of the results of that process happens to be that life is diverse.

quote:
Also, the older the population of organisms that scientist examine the greater their biodiversity. Which would indicate that the greatest amount of biodiversity occurs the closer you get to the ancestral paraphyletic community. So while life is indeed changing over time. The greatest type of diversity existed in the initial community, and thus life has not become increasingly diverse.

Incorrect. The reason why diversity is great in extremely old groups is that they've had the time to develop that diversity from a less diverse beginning which occured long ago.

quote:
Another premise of the current ToE.

No, it actually isn't.

quote:
...a community of paryphyletic cells... A stage that is extemely speculative and the current ToE by definition can never examine.

Right, because it's outside of that particular idea's realm, and thus can not possibly force a paradox on it. Evolution simply has nothing to do with the origin of life. That's biogenesis, not evolution.

quote:
I await your responses to this post because this perspective means that the Current ToE can never fully explain life's biodiversity (Yet, it seeks to do just that)

Not really. It explains why things are in their current form, without any measure of "diversity" being relevant. For example, the group "homonids" is much less diverse now than it has ever been before in the last couple of millions of years, and evolution gives part of the reason: most of the species in it have gone extinct because one of them evolved to outcompete the others (or they themselves failed to evolve to adapt to changes).

quote:
...the only implication of the theory is the minor observation that the Current ToE demonstrates that life varies over time.

No, that's the observed fact of evolution. The "theory of evolution" is something else, a misnomer referring to the theory of natural selection (which is actually a law at this point, not a theory anymore), which is an explanation of the main mechanism by which evolution works. See my first paragraph again.


This message is a reply to:
 Message 11 by Thmsberry, posted 03-17-2001 3:48 AM Thmsberry has not yet responded

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