Denial of evolution IV

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as to your claim about feathers, they are not "clearly" feathers at all..
many scientist dispute this and others flat out refuse it saying it is actaully is collegen fibrers that are beign mistaken for feathers since collegn is most likely to be perserved..


The evidence for feathers in a range of dinosaurs is overwhelming.
http://en.wikipedia.org/wiki/Feathered_dinosaur

I quote :

"A number of non-avian dinosaurs are now known to have been feathered. Direct evidence of feathers exists for the following genera, listed in the order currently accepted evidence was first published. In all examples, the evidence described consists of feather impressions, except those genera inferred to have had feathers based on skeletal or chemical evidence, such as the presence of quill knobs (the anchor points for wing feathers on the forelimb) or a pygostyle (the fused vertebrae at the tail tip which often supports large feathers).

Avimimus (inferred 1987: quill knobs)[8][9]
Sinosauropteryx (1996)[10]
Protarchaeopteryx (1997)[11]
Caudipteryx (1998)[12]
Rahonavis (inferred 1998: quill knobs)[13]
Shuvuuia (1999)[1]
Sinornithosaurus (1999)[14]
Beipiaosaurus (1999)[15]
Microraptor (2000)[16]
Nomingia (inferred 2000: pygostyle)[17]
NGMC 91 (2001)[18]
Cryptovolans (2002)[19]
Scansoriopteryx (2002)[20]
Psittacosaurus? (2002)[21]
Yixianosaurus (2003)[22]
Dilong (2004)[23]
Pedopenna (2005)[24]
Jinfengopteryx (2005)[25][26]
Juravenator (2006)[27][28]
Sinocalliopteryx (2007)[29]
Velociraptor (inferred 2007: quill knobs)[5]
Similicaudipteryx (inferred 2008: pygostyle; confirmed 2010)[30][31]
Epidexipteryx (2008)[32]
Anchiornis (2009)[33]
Tianyulong? (2009)[34]
Concavenator"
 
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Actually, fossils are good indicators of where to look in the genetic materials of modern creatures. For example, the changes over time in fish, in which the fore-fins become modified to support the fish in being able to raise its head out of the water, followed by subsequent fossils of 'fish' that have bones in their fins that are homologous with vertebrate fore-limb bones, suggests that one should look to the genetic mechanisms for fish-fins as precursor mechanisms for vertebrate fore-limbs, etc.

Hmm,. very good point, as i said i am here to learn also. I see your point, though what i meant was we must then extrapolate across the little fossils we have by saying...it must have happened like this(so many say this to me?)..



A classic example is when certain adaptations are lost. The change over time in developing teeth, which are present in fish and vertebrates with similar genetic mechanisms, was not lost in the modern birds (and was present in Archaeopteryx; i.e. that 'bird' had teeth). Rather, a single/few hormones are inactivated, derailing the teeth development in birds. If that hormone is artificially added, the teeth-development occurs, giving birds with teeth on their beaks.

I never got this, why would an adaption ever be lost? Lets say that mutation or muations occured to lose the teeth as you said..surly this would only happen in at the very most to 1 individual in a group> so wouldnt natural selection weed out such a small chagne to the general population? I suppose it would depend on the time it occured and therefore whether or not it was advantageous...but can we really suggest that the mutation to lose the teeth would "appear" at just such a time?
and if it did not. how do we explain the loss of teeth?

Fossils can be extremely suggestive, therefore, as to what to look for in microbiology, as there are remnant genetics still present, though no longer expressed, in modern species in many other areas of development, in which fossils can be an indication of where to look in extant species' genetic mechanisms.


Yes they CAN be, im sure most are not unless you can point me to evidence otherwise(which i will be happy to look at and be proven totally wrong)

The incorporation of viral DNA when the entire species becomes infected with a retrovirus, with a subsequent modification into new usages, is another area of strong interest in evolution. We've had many threads along those lines, and you might wish to do further reading before making your pronouncements as to the usefulness of fossils, etc. (I'm thinking of the retrovirus that assists in mammalian placental development, but there are about a dozen others identified).



Believe me, joining this forum IS my further reserach! I am here to be rebutted so I can get a good fix on where my opinions are in terms of the evidence out there etc..

My main point is, fossils dont prove evolutions MECHANISMS, they simply show us change over time
 
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The evidence for feathers in a range of dinosaurs is overwhelming.


I quote :

"A number of non-avian dinosaurs are now known to have been feathered. Direct evidence of feathers exists for the following genera, listed in the order currently accepted evidence was first published. In all examples, the evidence described consists of feather impressions, except those genera inferred to have had feathers based on skeletal or chemical evidence, such as the presence of quill knobs (the anchor points for wing feathers on the forelimb) or a pygostyle (the fused vertebrae at the tail tip which often supports large feathers).

Avimimus (inferred 1987: quill knobs)[8][9]
Sinosauropteryx (1996)[10]
Protarchaeopteryx (1997)[11]
Caudipteryx (1998)[12]
Rahonavis (inferred 1998: quill knobs)[13]
Shuvuuia (1999)[1]
Sinornithosaurus (1999)[14]
Beipiaosaurus (1999)[15]
Microraptor (2000)[16]
Nomingia (inferred 2000: pygostyle)[17]
NGMC 91 (2001)[18]
Cryptovolans (2002)[19]
Scansoriopteryx (2002)[20]
Psittacosaurus? (2002)[21]
Yixianosaurus (2003)[22]
Dilong (2004)[23]
Pedopenna (2005)[24]
Jinfengopteryx (2005)[25][26]
Juravenator (2006)[27][28]
Sinocalliopteryx (2007)[29]
Velociraptor (inferred 2007: quill knobs)[5]
Similicaudipteryx (inferred 2008: pygostyle; confirmed 2010)[30][31]
Epidexipteryx (2008)[32]
Anchiornis (2009)[33]
Tianyulong? (2009)[34]
Concavenator"


Hmm, so it may be overwhelming to you but many scientists disagree, as I say, when it comes to this particualr issue there simply are no absolutes as yet becuase for every plausible peice of evidence there pops up an implausible route for anther part of the transition rears its head. some scientists even believe that it was the other way around or that they both evolve along totally separate lines from a common ancestor..this is far from a concensus(not that that means its worng of course) so i wouldnt say its overwhelming!

and what is even more unlikely to me at this stage in my research(assumiing they did evolve into birds) is the mechanisms that are chellenged with producing such adaption and drastic reworking of an entire system.
 
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If that was true we'd all be single celled organisms.

Evolution always moves towards organisms that are most likely to reproduce. Whether we define that as good or bad is immaterial.

I dont think its so much if we define it as good or bad but rather if we define it as a direction at all. How can a blind process have direction?
it doesnt move "towards organisms most likely to reproduce", becuase it dosent move towards anythign, they are simply the results of a blind process
 
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Why are we still discussing this? There are extant fish species that have a range from fully amphibious to lower degree of amphibious.

If extant fish can be amphibious, why couldn't they be in the past?

Or are we denying the present also.

The fact that fish in the past can resemelbe fish now, proves nothign about either ancestry or evolutions mechanisms, it simply means that there was an amphibious fish in the past.
 
My main point is, fossils dont prove evolutions MECHANISMS, they simply show us change over time

While that is true, they give some pretty strong hints.

For example. the evolution of feathers is demonstrated by reptilian scales becoming long and tubular in some early fossils. Fossil evidence now permits a fair idea of how feathers evolved. Elongated scales becoming curved and then tubular, and then branching.

These early structures, elongated scales, may have evolved for display, and later been coopted for thermal insulation by becoming tubular, and later branched. Final elongation for flight is another example of a pre-existing adaptation being further modified by evolution for a different purpose again.

This theme of pre-adaptation is seen throughout the fossil record. The predecessors to amphibians were lobe finned fishes, like the extant coelacanth. Their fins were obviously not for support. However, their descendents, like Tiktaalik, living in stagnant fresh water, started to use those fins for support, to lift their heads to near the surface, for oxygen richer water. This, in turn led to the fins developing through evolution as stronger support, and the roof of the mouth becoming vascular for gas exchange, so those fishes could gain oxygen by mouthing surface water, including air bubbles. The vascular tissue became invaginated for more surface area, eventually evolving into lungs. The lobe fins became strong support, which served the animals just before the amphibians, and also the earliest amphibians themselves.

The fossil record shows (from sediments) that these fish lived in shallow and low oxygen fresh water. They also show primitive leg-like lobe fins in true fishes. A pre-adaptation. The development of lungs is shown in embryology, but the fossil early amphibians support that picture.
 
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While that is true, they give some pretty strong hints.

For example. the evolution of feathers is demonstrated by reptilian scales becoming long and tubular in some early fossils. Fossil evidence now permits a fair idea of how feathers evolved. Elongated scales becoming curved and then tubular, and then branching.


Once again, the evolution from scales to feathers is a lot more complex then merely "elongation". This simply trivializes the issue. I advise you too take a look at the astounding micro structures found on birds wings(without which they woudl be worthless)..
and once again, the very claim that the "feathers" on those dinosaurs from china are actauly feathers at all is a disputed area..






These early structures, elongated scales, may have evolved for display, and later been coopted for thermal insulation by becoming tubular, and later branched. Final elongation for flight is another example of a pre-existing adaptation being further modified by evolution for a different purpose again.


you see, things dont evolve FOR display...or FOR anythign for that matter, evolution has no forsight, so they either worked or didnt, thats how the theory goes.. and of course sayign "may" have is simply specualtion.(nothign wrong with specualtion of course, you just should avoid it becoming an absolute in your mind imo)





in terms of "Final elongation for flight", this again trivializes the kind of changes we would need to turn a scale(through which cold blood runs) into a feather!..Not to mention the fact that mutations would simply have to "keep up" in other areas. Evolution does not modify things "for a different purpose", infact modification implies foresight or planning so i would even be cautious of that word..its very easy to get trapped into looking at structes and simply convincing yourself evolution "co opted it" or it "coevolved " alongside other stuctures simply BECUASE there are other structures e.g. Girrafes neck and heart simply had to coevolve alongside each other, and for me the fact that they are now both there and working to keep the girrafe alive does not prove a mechanism, but merely that they are there.


I personally believe at the moment, that co evolution of parts through stochastic processe and natural selection,while sounding plausible, breaks down when we apply it to nature!(opinion subject to change)






This theme of pre-adaptation is seen throughout the fossil record. The predecessors to amphibians were lobe finned fishes, like the extant coelacanth. Their fins were obviously not for support. However, their descendents, like Tiktaalik, living in stagnant fresh water, started to use those fins for support, to lift their heads to near the surface, for oxygen richer water. This, in turn led to the fins developing through evolution as stronger support, and the roof of the mouth becoming vascular for gas exchange, so those fishes could gain oxygen by mouthing surface water, including air bubbles. The vascular tissue became invaginated for more surface area, eventually evolving into lungs. The lobe fins became strong support, which served the animals just before the amphibians, and also the earliest amphibians themselves.




Again, you are simplifying the sheer magnitude of the task you are settign evolutions mechanisms to come up with.. to say "This in turn led to the fins developing through evolution as stronger support" is almost lamarkian! the fact that they "lift their heads to the surface" did not lead to anything.

we need to be carefull about not forgetting to reevaluate the mechanism when we come across adaption instead of automatically "knowing" the mechanism did it and therefore constructing a trivailzed story around it.
 
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Bear in mind that this is a detective story - you're not likely to find definitive answers to things that happened billions of years ago, only ways that things might have happened that are consistent with what we can observe now. (Many creationists seem to hate that. They seem to hold 'science' to a different standard.)


So what your saying is it definatly happened? we just dont know how?
seems to me after reading your papers, that we dont have a clue!
and I dont blame them. Although they make many guesses about the ancestry of this enzyme, they never adress the fact that it would simply HAVE to be there the very first time a double stranded dna replicated!
At this moment in my reserach, i simply cannot take that on faith, that it coudl be "hit on" and coevolve with the dna duplex stretches credibilty to the very limit! Thanks for the papers.








My understanding of molecular evolution in general is that new functions often evolve from older similar functions.

It seems clear that supercoiled DNA would not be possible without mechanisms to split and join DNA.

If so, then mechanisms to split and join DNA must have existed before supercoiling.

Oh, simple as this eh? it "must have"... and go form there? wow



If so, there must a use for those mechanisms before supercoiling - like DNA or RNA repair mechanisms?


Im not talking about enzymes that purposflly supercoil the dna helix for an advangate, im talking about the natural(and drastic) supercoildign that occurs as the replication fork moves forward..this must be relieved, and to suggest that topo or its ancestres were "there on time" is ludacris to me at the moment!






But I'm speculating. Here are some recent articles that look interesting and relevant (for the possible evolution pathways of the supercoiling mechanism, the possible selection pressures, and for the detective work involved), but that I haven't read. Let me know which ones you can't access the full text.
 
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Once again, the evolution from scales to feathers is a lot more complex then merely "elongation". This simply trivializes the issue. I advise you too take a look at the astounding micro structures found on birds wings(without which they woudl be worthless)..
and once again, the very claim that the "feathers" on those dinosaurs from china are actauly feathers at all is a disputed area..

It is more definitive than you realise. The chemistry of the keratin in reptile scales versus bird feathers is different. Some of the dinosaur fossils with feathers have actually left traces of that keratin in rock, which has been analysed. Guess what? The type of keratin is feather keratin, not scale keratin.
 
So what your saying is it definatly happened? we just dont know how?
seems to me after reading your papers, that we dont have a clue!
Not my papers.
And no, I'm not saying anything definitely happened.
And yes, we don't have and probably never will have any real clues into what happened. All we can do is guess, and consider the possibilities.

What do you expect?

and I dont blame them. Although they make many guesses about the ancestry of this enzyme, they never adress the fact that it would simply HAVE to be there the very first time a double stranded dna replicated!
Don't they? I find that surprising. Have you really read those papers? Could you access them all?

Oh, simple as this eh? it "must have"... and go form there? wow

Im not talking about enzymes that purposflly supercoil the dna helix for an advangate, im talking about the natural(and drastic) supercoildign that occurs as the replication fork moves forward..this must be relieved, and to suggest that topo or its ancestres were "there on time" is ludacris to me at the moment!
Ok, so same applies - there must be a reason for those DNA modifying enzymes to have already existed.

Nobody suggests that the enzymes for cutting and joining DNA simply appeared just as they were needed for replicating long double DNA strands. As you said, that would be ludicrous.

Therefore, there must be some other reason for DNA cutting and joining enzymes to exist. We may never know what that reason was. Would you like to guess?


Here's some questions for you to think about:

How long a section of double stranded DNA can be replicated at least some of the time without a topoisomerase?

What are the advantages of double-stranded over single stranded DNA

What functions does topoisomerase have that would be useful for maintaining a single-stranded DNA genome?

Did you know there is a quote button above this post?
 
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wow

It is more definitive than you realise. The chemistry of the keratin in reptile scales versus bird feathers is different. Some of the dinosaur fossils with feathers have actually left traces of that keratin in rock, which has been analysed. Guess what? The type of keratin is feather keratin, not scale keratin.


well first off, I see you didnt deal with any of my other points.
Second, if what you say is true then that is extremley intersting and would be the best evidecnce yet. got a link?
 
topoismimerase, the molecular magician!

And no, I'm not saying anything definitely happened.
And yes, we don't have and probably never will have any real clues into what happened. All we can do is guess, and consider the possibilities.

What do you expect?


okay, first off(I don't join many forums!) i actully dont know how to use the quote function...sorry about that(any directions on the site?)..
anywho...




okay i didnt actually mean they were your papers...just the ones you sent me. Yes, but you see, just beucase you dont know and admit that, that doesnt stop these guys writing the paper from already deciding what happened and going from there!
you see, before they write up the paper, the should(maybe they did who knows eh) reevaluate the mechanisms they are charging with "bringing about" the enzyme, along with its initiator at the same time, along with its binding site for atp and all at just the right time. They even come to teh conclusion that it originated multiple times in many forms separatly and ALL of these "origination events" occured extremly early in the FIRST ancestor!
Not only is this guesswork but its absolutly stretching the boundaries of specualtion to their limit. This enzyme is mind blowing and i cannot simply ascribe the blind mechanisms of evolution to its "creation"..(not yet anyway!)





Don't they? I find that surprising. Have you really read those papers? Could you access them all?


Well, of course there were 1 or 2 i think i couldnt acess but i am activly downloading as many papers as i can from google scholar which is great.
But of course I am also reading alberts molecular biology of the cell and watching youtube lectures and not even those two sources addressed it. They certainly addreseed its importance in maintaning DNA's fidelity at replication and repair but nothign about its co evolution of parts and its "timely arrivel" on the scene....



Ok, so same applies - there must be a reason for those DNA modifying enzymes to have already existed.


Infact, there is NO reason for anythign to have existed unless you already think you know how it came about. And of course, saying there must have been a reason just brings the same question backwards in tme, becuase as soon as it was needed, it was there! we have to ask ourselves, before we consider how it originated through evolutions proceses, rather could it!
and could it "on time"...its like the evolution of the sexes or the anchor fish mating ritual or girrafes neck etc, co evolution on such a scale as to be basically impossible!(opinion subject to change )




Nobody suggests that the enzymes for cutting and joining DNA simply appeared just as they were needed for replicating long double DNA strands. As you said, that would be ludicrous.



Well infact i have heard that they did indeed "appear" and have heard that same term in reference to the origin of many cellular parts. So if, as you say, its is ludacris(which i wholeheartedly agree with), then what did DNA do the first time it replicated, or repaired itself and needed to releive super coiling..(this is forgetting about the gobsmackngly complex replication and repair holoenzymes!)....what did it do? did it "recruit" other proteins at just the right time? now that would be a miracle...



Therefore, there must be some other reason for DNA cutting and joining enzymes to exist. We may never know what that reason was. Would you like to guess?




We may never no what the reason was.....but ther WAS a reason right?
there....MUST have been.....BECAUSE its here now? personally i wouldnt make any claims to know ANYthign about its origin, so i wont even speculate.(sorry bout the caps, just obviiosly need to emphazise some parts of the text)





Here's some questions for you to think about:

How long a section of double stranded DNA can be replicated at least some of the time without a topoisomerase?


To my knowledge, none, because as soon as you have 2 strands with 2 full turns of about 20 base pairs, coling insues...but anyway im not saying such a state of DNA couldnt have existed, i am referign to the tiem when it did need to be negativley supercoilded to relieve,well, positive suepercoiling!




What are the advantages of double-stranded over single stranded DNA

what releveance does this have to the topoisimerase?



What functions does topoisomerase have that would be useful for maintaining a single-stranded DNA genome?


mayve its cleavage function? or its ligase like function for sealing breaks..




Did you know there is a quote button above this post?[/QUOTE]
 
tsk tsk

No, but you're certainly justified in judging it by the ones who are chosen to be its leaders. Integrity is simply not a major concern for these people.


so then do you judge america by its leaders? do you judge science by its leading scientists, to you judge a town by its mayor?
you have to stop worrying about the persons involved and worry about the information presented, which is unfortuntly not all rubbish, though most probably is. You see, though these people are dangerous becuase of a prior commitment to a particaulr text, they are not the only ones questioning evolution, and the fact that they are so driven by there theism means they go to great lenghts to dig out some very interestign facts...

For instance, i recently found on a creationist sight a very intersting article on the apparent problem of chirality in terms of an natural cause for abiogeneiss. I have since done the reserach and have yet to see a senseible argumetn to account for the chirality of boht dna and amino acids. Its quite a predicamnet for any abiogenesis model...
 
The fact that fish in the past can resemelbe fish now, proves nothign about either ancestry or evolutions mechanisms, it simply means that there was an amphibious fish in the past.

There is actually an amphibious fish in the current time. That is what extant means.

Sorry if I use difficult words.

And actually the current amphibious fish doesn't resemble the predecessor of amphibians at all.
 
well first off, I see you didnt deal with any of my other points.
Second, if what you say is true then that is extremley intersting and would be the best evidecnce yet. got a link?


http://en.wikipedia.org/wiki/Feathered_dinosaur

I quote :


"more than twenty genera of dinosaurs, mostly theropods, have been discovered to have been feathered. Most fossils are from the Yixian formation in China. The fossil feathers of one specimen, Shuvuuia deserti, have tested positive for beta-keratin, the main protein in bird feathers, in immunological tests."

The other points you raised seem to be the claim that there is too much and too complex a change to be explainable by the mechanisms I posted.

Perhaps true, but you have to start somewhere. If that is your argument, it is starting to get ominously like a creationist argument. These have been fought out in enormous detail by others, and I am not sure I want to go down that road. We might still be at it next decade!

As MacGillivray points out, the coelacanth is a currently living species of lobe finned fishes. it is not, of course, an ancestor to the amphibians, and still lives in the sea like its ancient forebears.

However, other, and very ancient lobe finned fishes have left fossils in sediment characteristic of shallow fresh water environments. There appears to be a transition towards limb development for support. This is not Lamarckism. The individuals without reasonable support would not have reproduced, and Darwinian evolution has caused changes resulting in stronger supporting fins.
 
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I quote :


"more than twenty genera of dinosaurs, mostly theropods, have been discovered to have been feathered. Most fossils are from the Yixian formation in China. The fossil feathers of one specimen, Shuvuuia deserti, have tested positive for beta-keratin, the main protein in bird feathers, in immunological tests."


unfortuantly, now that i look at it(i actually read this wiki page earlier but missed this part) i really dont see this as great evidence and the reasons are

A. it was found in a structure that is hotly contested to even be a feather!
other scientists are convinced it is collegen, found in bones, which brings me to my next point

B. Bones have beta keratin in them, and can be incorporated into the strcuture for better bone mass! so its not at all unusual to find bones with beta keratin in them. Using it as evidence becuase it is "the main protein in birds feathers" is kind of odd sinece its also the main protein in many other structures.

Im not saing its not evidence, and I'm not even saying I have a problem with common ancestry or one speices evolving into another, only that i am as of yet unconvined.




The other points you raised seem to be the claim that there is too much and too complex a change to be explainable by the mechanisms I posted.

Perhaps true, but you have to start somewhere. If that is your argument, it is starting to get ominously like a creationist argument. These have been fought out in enormous detail by others, and I am not sure I want to go down that road. We might still be at it next decade!


So it is perhaps true? doesnt that mean those "creationist arguments" have not truly been rebutted as you sugest?
If one takes a logical look at what is required of mutations and selection in this case, especially with the coevolution of parts, it becomes very obvious how unlikely it is to have occured. And of course, somethign can be so implausible that, though technically possible, will never actaully happen!

we cant look at the fossils and say, oh the mechanisms did it!
we must say, hmm, these fossils look like evidence that these organisms are somehow related through time, and thats intersting, but the mechanissm are a totally different kettle of amphibious fish!!






As MacGillivray points out, the coelacanth is a currently living species of lobe finned fishes. it is not, of course, an ancestor to the amphibians, and still lives in the sea like its ancient forebears.

However, other, and very ancient lobe finned fishes have left fossils in sediment characteristic of shallow fresh water environments. There appears to be a transition towards limb development for support. This is not Lamarckism. The individuals without reasonable support would not have reproduced, and Darwinian evolution has caused changes resulting in stronger supporting fins.[/QUOTE]


The same argument i made above goes here.
Those fossils suggest that forms of fossils may well be linked through time, on the other hand, they may simply look alike.
Just becuase they look like they are going towards somethign, i could say that about anything alive today, yet evolution has no "towards" anything so its a strange one!

thanks for the reply!
 
okay, first off(I don't join many forums!) i actully dont know how to use the quote function...sorry about that(any directions on the site?)..
anywho...
No problem. Try this page: BB Code List
Briefly, a bbcode 'tag' is a keyword in square brackets. Tags usually come in pairs (the second one has a slash before the keyword), and apply some formatting to the text between them.
For example, anything that's surrounded by quote tags, like this:
[noparse]
This will be a quote
[/noparse]
Appears like this:
This will be a quote

Clicking the 'quote' button above a post automatically quotes the entire post and puts your cursor at the bottom, but you can go up into the post and type your own tags to cut the quote into sections for a piecewise reply.
You can also use the toolbar in the advanced editor to put tags in for you.

The piecewise reply thing works reasonably well as a discussion technique, although it can get a bit unwieldy when replies get longer and sidetracks develop. You can find yourself carrying on several different conversations with one person!
 
okay i didnt actually mean they were your papers...just the ones you sent me. Yes, but you see, just beucase you dont know and admit that, that doesnt stop these guys writing the paper from already deciding what happened and going from there!
Are you sure they're not suggesting a possibility and exploring the potential consequences?
Perhaps you could give an example?
you see, before they write up the paper, the should(maybe they did who knows eh) reevaluate the mechanisms they are charging with "bringing about" the enzyme, along with its initiator at the same time, along with its binding site for atp and all at just the right time.
Who do you mean, specifically?
Who has said that a particular enzyme and associated machinery appeared at exactly the same time as it was required?

They even come to teh conclusion that it originated multiple times in many forms separatly
Yes. That part isn't guesswork, but detective work.
and ALL of these "origination events" occured extremly early in the FIRST ancestor!
No, that's doesn't match what I've read. Who came to that conclusion?
Not only is this guesswork but its absolutly stretching the boundaries of specualtion to their limit. This enzyme is mind blowing and i cannot simply ascribe the blind mechanisms of evolution to its "creation"..(not yet anyway!)
Probably because you've mislearned the supposed evolutionary origins from creationist sources.

Well, of course there were 1 or 2 i think i couldnt acess
Which ones? I'll email them to you if you like.

But of course I am also reading alberts molecular biology of the cell and watching youtube lectures and not even those two sources addressed it. They certainly addreseed its importance in maintaning DNA's fidelity at replication and repair but nothign about its co evolution of parts and its "timely arrivel" on the scene....
A molecular biology text is chiefly concerned with molecular biology as it is *now*, not as it was 4 billion years ago. And Youtube? Needles and haystacks spring to mind.
And once again, you're looking for knowledge that we don't have. We don't know and perhaps can't know the details of what happened. All we can do is speculate, and examine whether those speculations are consistent with what we see now.

Infact, there is NO reason for anythign to have existed unless you already think you know how it came about.
I don't know what you're thinking. We can look at something and see the reason for its existence in it's apparent purpose, its function. No origin theories required.
And of course, saying there must have been a reason just brings the same question backwards in tme, becuase as soon as it was needed, it was there! we have to ask ourselves, before we consider how it originated through evolutions proceses, rather could it!
and could it "on time"...its like the evolution of the sexes or the anchor fish mating ritual or girrafes neck etc, co evolution on such a scale as to be basically impossible!(opinion subject to change )
No, it doesn't work that way. That's a typical creationist caricature of evolution.
Actual evolution is about combinations and subtle changes in existing machinery or its environment, that sometimes results in new useful functions.

The idea that some amazing biological functions seen today sprang into existence fully formed is creationism. It is no part of evolution.


Well infact i have heard that they did indeed "appear" and have heard that same term in reference to the origin of many cellular parts.
Where did you hear it? In what context?
So if, as you say, its is ludacris(which i wholeheartedly agree with), then what did DNA do the first time it replicated, or repaired itself and needed to releive super coiling. (this is forgetting about the gobsmackngly complex replication and repair holoenzymes!)....what did it do? did it "recruit" other proteins at just the right time? now that would be a miracle...
Like I said, the required machinery must have been there already, and performing some pre-existing function. Why is that miraculous?

We may never no what the reason was.....but ther WAS a reason right?
there....MUST have been.....BECAUSE its here now?
Absolutely correct.

personally i wouldnt make any claims to know ANYthign about its origin, so i wont even speculate.
Then why are we having this discussion?
I think you do very much want to speculate on origins.
Isn't that what creationism is?

How long a section of double stranded DNA can be replicated at least some of the time without a topoisomerase?


To my knowledge, none, because as soon as you have 2 strands with 2 full turns of about 20 base pairs, coling insues...but anyway im not saying such a state of DNA couldnt have existed, i am referign to the tiem when it did need to be negativley supercoilded to relieve,well, positive suepercoiling!
Are you confusing coiling with supercoiling? Or are you only thinking of circular DNA?
Many full turns of non-circular DS DNA can be replicated before supercoiling becomes a problem, because the tension in the double helix can be relieved by twisting the whole molecule. It would have to be pretty long before that twisting results in a supercoiled tangle.

What are the advantages of double-stranded over single stranded DNA

what releveance does this have to the topoisimerase?
The relevance is that there would have been a reason for DNA manipulation before long DS DNA existed.

What functions does topoisomerase have that would be useful for maintaining a single-stranded DNA genome?

mayve its cleavage function? or its ligase like function for sealing breaks..
Right, so the functions of DNA topoisomerase might have been performed less efficiently by other enzymes, at least for short DNA segments.

Can you see the potential for gradual change? As DNA maintenance machinery gradually becomes more efficient, it can gradually maintain longer and longer DNA strands.

There is no point at which development is halted unless several things appear at once.
 
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