Punctuated Equilibria theories

[TeleMad]

Now I've become convinced that this creationist-style "we don't see any intermediate species" is the only proof that you're refering to in your statement that "mutation has no role in speciation" ...

 

It's not the only Creationist portion of his "theory" (despite some people's here inability to see it, like bumab). There's also the "poofing" into existence of the first prokaryote fully loaded with genetic information for hearts, ears, eyes, heads, mouths, lungs, colons, hair, fruit, etc. And there's also the divine protection of that information load to prevent it from being degraded over 3 billion years of nonuse.

[TeleMad]

I never presented a theistic aspect. It is true that I imputed more information load into the first prokaryotye, but I never drew any conclusions about the solution to that problem. There are several possibilities.

 

Only religious ones. Not only do you have to explain how all of vast unused code got into the first prokaryote, but also how it remained intact over the course of 3 billions years of nonuse. Do you propose that aliens created the first prokaryote and then watched over their creation for 3 billion years - hell, EVEN TO THIS DAY - somehow magically protecting all of the not-yet-used genetic information in DNA from degrading via mutations? Go ahead, you'll just be laughed at.

 

The ONLY real possibility your "theory" offers is a supernatural God.

[TeleMad]

Apparently, ubliquitin is one of the most conserved protiens known,

 

The most conserved I can think of off the top of my head are histones: proteins associated with nucleosomes in eukaryotes.

 

bumab: ... meaning the basic structure of ubiquitin has not changed over the years, and apparently significantly less overall then most other protiens. Facinating! I'm not sure whose hypothesis this applies most too ...

 

Well, it does show what functional constraint does to functional sequences: it rejects most mutations, keeping the sequence relatively stable over long periods of time.

 

The opposite - what happens to nonfunctional sequences - is best seen by looking at things like pseudogenes, introns, and intergenic sequences, where the nucleotide sequences diverge very rapidly (in a history-of-life type context). This feature of nature is one nail in the coffin of Biochemist's front-loaded first-prokaryote "theory".

[TeleMad]

1) "lysoome" is used ambiguously to mean either a set of degradatory intrecellular organelles, or a particular one.

 

Care to support that assertion?

[TeleMad]

[biochemist] You're the biochemist...

 

That's a good one! You're a riot bumab!

[bumab]

We do, and I posted it. But for some unknown reason, bumab or infamous claimed it was irrelevant. Yet here you are BEGGING for it!

 

Plant speciation by chromosomal rearrangment is irrelevent, since it operates under a different set of constraints. PLEASE read the posts through...

[bumab]

It's not the only Creationist portion of his "theory" (despite some people's here inability to see it, like bumab)......

 

For the last time, it's just a different difficulty. For the love of God, I agree with you on the information load subject!!!!! Relax!!!

 

I'm done with this for a while.

[TeleMad]

In plants. Speciation through chromosomal level events (polyploidy and the like) are readily done in plant species, over and over. They do not seem to have the same level of regulatory vigalence animals do. So, plants are not really a valid example in this discussion, since the mechanisms are obviously somewhat different.

 

Polyploidy / genome duplications occur in animals too...

 

"As mentioned in the introductory part of this chapter, the fact that certain closely related 'sibling' species of fish and amphibians differe by a factor of two in their chromosome content proves that genome duplications are permissible [in animals]." (Protein Evolution, Laszlo Patthy, Blackwell Science, 2000, p205)

[TeleMad]

Definitly, that's why I brought those up earlier. Can we set up an environment where those are selected for, however?

 

The bithorax mutation produces an extra body segment in the fly. Many animals's bodies are composed of such repeated "identical" segments and the bithorax mutation in flies is a good match. As an explanatory example, if a 5" centipede, with an extra body segment, is more fit than the normal 4" centipede, then the mutation that duplicated the body segment would be advantageous and selection would tend to preserve it, and hence, 5" centipedes would come to be the dominant form.

 

I don't see any logical contradictions or problems in any of that type of reasoning. (But I guess someone will claim that it is simply impossible - well, at least for nature to do).

[Biochemist]

The bithorax mutation produces an extra body segment in the fly. ...

This is not an example of a new body plan.

[paultrr]

Two short definition differences:

 

Autophagy, the process by which cells recycle cytoplasm and dispose of excess or defective organelles.

 

Phagocytosis the ingestion of a smaller cell or cell fragment, a microorganism, or foreign particles by means of the local infolding of a cell's membrane and the protrusion of its cytoplasm around the fold until the material has been surrounded and engulfed by closure of the membrane and formation of a vacuole: characteristic of amebas and some types of white blood cells.

[TeleMad]

This is not an example of a new body plan.

 

It is in line with what you yourself called “dramatic morphology changes”

 

Biochemist: If we examine the genotypic nature of dramatic morphology changes (like the extra frog leg) ....

 

and that's what I was asked about.

 

 

 

By the way, what right do you have to ask someone else to demonstrate a new body plan, when your replacement "theory" has the genetic information encoding neurons and brains, hearts and blood vessels, trachea and lungs, arms and legs, eyes and ears, kidneys and ureters, livers and gall bladders, muscles and tendons, penises and vaginas, bones and ligaments, and so on, poofing into existence all at once in the first prokaryote?

 

You complaining because you feel science can’t explain a walk up a relatively smooth incline to reach the top of a mountain, whereas your replacement involves a single leap from base to summit!! Only Superman, or gee, maybe God, could make that leap your replacement requires.

[Biochemist]

It is in line with what you yourself called “dramatic morphology changes”

Don't change the subject. We are discussing widely accepted theory related to PE. The accepted theory suggests that new body plans arrive suddenly, and that the fossil record is much more correctly charactized by stasis than gradual change. The example you offered was not anew body plan.

[Biochemist]

.. what right do you have to ask someone else to demonstrate a new body plan, when your replacement "theory" has the genetic information..poofing into existence all at once in the first prokaryote?

This issue has been dealt with previously in this thread. I was trying to formulate a credible hyposthesis to address the issues described in the fossil record, and usually characterised as "punctuated equilibrium". I was not trying to address abiogenesis.

 

 

 

 

1. There is absolutely no evidence for rapid mutation-based speciation, or for that matter, ANY speciation based on mutation
   
2. There is apparently a sudden arrival of new body plans in the fossil record
   
3. The fossil record is characterized by long periods of stasis.
   
4. We have demonstrated many biochemical mechanisms to extend and modify existing genes, and all of them have a high degree of specificity. There is no evidence that they are mutative. They could as likely be part of the genetic program.
   

My conclusion (based on extant fact) is that the notion of rapid speciation based on complex mutation strains credulity. Further, there is also absolutely no empirical evidence supporting it.

 

If you elect to reject a hypothesis based on the empirical evidence because you dissapprove of the implications, that is not science. It is faith. You have articulated this faith-based position previously, and you are welcome to hold it. I have no issue with faith based positions.

 

FYI, I don't think anyone has offered a reasonable explanation for abiogenesis anyway.

[TeleMad]

Don't change the subject.

 

I didn't change the subject. I replied to what I was asked about. I discussed same kind of thing you yourself discusseed in this thread.

[TeleMad]

There is absolutely no evidence for rapid mutation-based speciation, or for that matter, ANY speciation based on mutation

 

False. I already provided an example: a new species arising in nature and the transition being duplicated in the lab, in just 4 generations.

 

Biochemist:There is apparently a sudden arrival of new body plans in the fossil record

 

I may have missed it, but didn't see you give an exact definition of term "body plan". Got one?

 

Biochemist: The fossil record is characterized by long periods of stasis.

 

And we know that not all evolutionary changes get preserved in the fossil record. For example, industrial melanism and changes in beak morphology in Darwin's finches.

 

Biochemist: We have demonstrated many biochemical mechanisms to extend and modify existing genes, and all of them have a high degree of specificity. There is no evidence that they are mutative. They could as likely be part of the genetic program.

 

Sorry, but that statement sounds kind of like double-talk to me. Are you denying that mutations can modify existing genes?

 

 

Biochemist: My conclusion (based on extant fact) is that the notion of rapid speciation based on complex mutation strains credulity. Further, there is also absolutely no empirical evidence supporting it.

 

By COMPLEX mutation? Why COMPLEX? We have examples of rapid speciation based on mutation: there's the one example I gave, and any others that probably exist but I am not personally aware of.

 

Biochemist: If you elect to reject a hypothesis based on the empirical evidence because you dissapprove of the implications, that is not science. It is faith.

 

False. You're trying to substitute a miracle for science. I reject that.

 

Biochemist: You have articulated this faith-based position previously, and you are welcome to hold it. I have no issue with faith based positions.

 

And now you try some good old equivocation. I've seen you play your childish tricks on others in this thread.

 

It is your anti-science, religious position that is based on faith: a completely different kind of "faith" than one has in science.

[paultrr]

I might not get to see the answer for another month or two since I will be traveling some, but, you're replacement theory as someone else has termed it seems to still be evolution of sorts with the difference being all the primary genetric coding was already there in the first cells. So my question would be, and forgive me if this has already been given, just how and where did those first primitive cells with all that genetic code come from?

 

I ask this question because I believe this is where most scientists would begin to take major exception on. I am assuming in the back of my mind that when it comes to explaining the origin of those first cells you revert to claiming a devine act. Forgetting for a moment that a majority of us scientists tend to see no evidence of a devine being of any sort it still seems to me that in the end run the only thing this alternative theory manages to do is shift the big question of where did it all come from back beyond the historical record period. The rest of the way up it isn't that much different from evolutionary theory at all. That rather returns the problem with the theory back to what most of us see it as anyway. That being an evolutionary version of special devine creation. It also if one discounts the "God" equation suffers from the same problem creationists tend to claim we have of explaining how non-living became living.