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Theories - Origin of Life

Discussion of everything related to the Theory of Evolution.

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Re: Theories - Origin of Life

Postby wbla3335 » Sat Jan 28, 2012 4:50 pm

scottie wrote:You are clearly out of your depth here

An armchair biologist/creationist suggesting that an evolutionary biologist is out of his depth in a discussion of evolution? Can you consider the possibility it might be the other way around? Just maybe?
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Re: Theories - Origin of Life

Postby ughaibu » Sun Jan 29, 2012 7:19 am

scottie wrote:So is the hypothesis of decent from a common universal ancester correct?

Well it can only be regarded as correct if it can be demonstrated to be so.
You seem to be equivocating over technical and colloquial definitions of "hypothesis". Evolutionary theories which posit a universal common ancestor will allow the generation of hypotheses which either will or won't adequately predict the probability of making certain observations. However, such theories do not entail ontological commitment to the models which are posited within them, predictive accuracy is independent of ontological correspondence. So, conjecturing about the historical fact or otherwise of a universal common ancestor isn't important for evolutionary theory, and in any case, is not a question which can be settled by observation.
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Postby biostudent12 » Sun Jan 29, 2012 12:17 pm

What about he endosymbiotic theory? You could look into that.
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Re: Theories - Origin of Life

Postby scottie » Mon Jan 30, 2012 3:56 pm

biostudent12 » Sun Jan 29, 2012 12:17 pm
What about he endosymbiotic theory? You could look into that.

Thanks for your suggestion.
Yes I have looked into this theory in some detail and have covered it before.
However here is a good explanation of the theory.
http://users.rcn.com/jkimball.ma.ultran ... iosis.html
This is the theory that eukaryotic cells arose as a result of one prokaryotic cell engulfing (without digestion) another cell. The engulfed cell becomes the mitochondria or chloroplasts of the new cell. These have their own circular genome carry out transcription and translation and replicate independently of the host cell by binary division, similar to bacteria.

There are several problems with it.
For example the mitochondria’s genetic code is at variance with the standard DNA code. The codon UGA is a stop codon in the standard code, but encodes for Tryptophan in mitochondria. ( I have covered this before)
This means that the genes of the ingested prokaryote would have had to have been re-coded (somehow) on their way into becoming the nucleus of the emerged eukaryote. How does that happen? Remember the two prokaryotes have the same DNA code to begin. There are a lot more details I can elaborate on, but I hope you get the point.

Then there is another problem. The mitochondrial protein is tagged with an extra length of polypeptide to ensure that is recognised by the cell as a product of the mitochondria.
What unguided and random processes can produce a different symbolic meaning to the code and also know of a need to identify the origin of a protein.

Any naturalistic theory cannot answer these questions.
But it gets worse.
There is the additional problem of energy requirements.

In a review article by Nick Lane and William Martin published in Nature in Oct 2010
http://www.nature.com/nature/journal/v4 ... 09486.html
This problem is addressed.
The energetics of genome complexity
The abstract reads
All complex life is composed of eukaryotic (nucleated) cells. The eukaryotic cell arose from prokaryotes just once in four billion years, and otherwise prokaryotes show no tendency to evolve greater complexity. Why not? Prokaryotic genome size is constrained by bioenergetics. The endosymbiosis that gave rise to mitochondria restructured the distribution of DNA in relation to bioenergetic membranes, permitting a remarkable 200,000-fold expansion in the number of genes expressed. This vast leap in genomic capacity was strictly dependent on mitochondrial power, and prerequisite to eukaryote complexity: the key innovation en route to multicellular life.

The energy requirement in processing the eukaryotic DNA is far greater that what is available by a bacterial cell.
The ATP requirement by necessity, requires the presence of mitochondria.
Do you see a chicken and egg situation here?

The number of mitochondria varies according to the type of cell, between one and 10,000 with an average of about 200.
The human liver has over 1,000 mitochondria.
Now ask yourself just one question
How does the mitochrondria know how many divisions are necessary for each type of cell?

Why do you think that these reviews postulate that this has happened only once?
Simply because the odds are so remote that a one off event is the only one that can even be put forward as hypothesis.
None of these questions can be answered except as a result of design requirements.
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Re: Theories - Origin of Life

Postby wbla3335 » Tue Jan 31, 2012 2:42 am

scottie wrote:Any naturalistic theory cannot answer these questions.

None of these questions can be answered except as a result of design requirements.

I guess this is why you can't reason like a scientist. You must really, really want to believe in that god of yours. I'm curious why.
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Re: Theories - Origin of Life

Postby scottie » Tue Jan 31, 2012 1:46 pm

wbla3335

This is all so sad.
You are sounding more and more like Richard Dawkins.
That poor fellow has had to retire from educating the public on science matters, so like any faithful disciple you appear to be doing the same. :)
And why not?
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Re: Theories - Origin of Life

Postby wbla3335 » Tue Jan 31, 2012 5:53 pm

scottie,

I'm a fan of Dawkins the biologist, not Dawkins the atheist. But the guy's 70 years old - I don't think he was forced to retire, as you imply. What's sad is your pretension to understanding things you don't. Better people than you have been trying longer than you to debunk evolution, without success. No one has ever come to a belief in a god by a rational analysis of the available evidence. That's no proof one does not exist, just unlikely to. Believers have either been indoctrinated from birth or have a need to believe in something other than the natural world. I don't mind you believing in whatever you wish, and I don't mind your efforts to justify your belief (although you DO need to research more deeply before heading down blind alleys), but you really must stop making silly statements like those I have recently quoted.
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Re: Theories - Origin of Life

Postby Nick7 » Tue Jan 31, 2012 11:57 pm

wbla3335 wrote:That's no proof one does not exist, just unlikely to..

Likely / unlikely…. You are quantifying something that is, as it stands, unquantifiable, cause we lack knowledge, enough evidence and even capacity to gather enough evidence. At the same time you offer little to debunk Scottie’s statements, cause you don’t want to waste your time on Scottie-the-engineer. That’s understandable, but Scottie is a conduit. All these ideas are most likely (let Scottie correct me) are gathered from your peers. For instance, Brown Norway rat reasoning from page 34, as far as I know, was first made by your colleague ( http://www.richardsternberg.com/biography.php ). Just like all the other arguments presented can be traced to biologists, geneticists, …. Are those people aware that their conclusions point at something that is unlikely and it’s silly to even waste time on it?
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Re: Theories - Origin of Life

Postby ughaibu » Wed Feb 01, 2012 1:21 am

Nick7 wrote:
wbla3335 wrote:That's no proof one does not exist, just unlikely to..
Are those people aware that their conclusions point at something that is unlikely and it’s silly to even waste time on it?
Gods are fictional characters and I think that it's highly unlikely that the conclusions of Wbla3335's "peers", regardless of what you mean by that, suggest the reality of those fictional characters.
1) if "their conclusions point at something that is unlikely" is not intended to mean 'their results point to the conclusion that real gods exist', please clearly explicate your meaning.
2) if "their conclusions point at something that is unlikely" is intended to mean 'their results point to the conclusion that real gods exist', please clearly present an argument in support of that contention.
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Re: Theories - Origin of Life

Postby wbla3335 » Wed Feb 01, 2012 1:54 am

Nick. Absolute knowledge is a rare animal. The best we mortals can do is to deem something more or less likely than something else. As ughhaibu alludes to, the findings of science often differ from the interpretations of those findings, particularly unqualified and prejudged interpretations.
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Re: Theories - Origin of Life

Postby Nick7 » Thu Feb 02, 2012 12:09 am

ughaibu wrote:Gods are fictional characters.

I know… :? . I’ve read it somewhere already... Gods are fictional characters… Religion is the opium of the people….. Yeh, I believe this stuff was in my soviet 4th grade “History of the Ancient World” text book. But I have kinda already deviated from a black’n’white perception of controversial issues of that nature by now.

ughaibu wrote: I think that it's highly unlikely that the conclusions of Wbla3335's "peers", regardless of what you mean by that, suggest the reality of those fictional characters.

Well, the guy I mentioned above is an evolutionary biologist with Ph.D. in Molecular Evolution and Ph.D. in Theoretical Biology, which would (I assume) make him Wbla335’s peer. If you open the link above and read his one-paragraph introduction called “My approach to the study of biology”, you will see that, yes, his conclusions (conclusion / opinion / way of thinking…. Whatever you wanna call it) suggest a possible “reality of those fictional characters” in one form or another. That’s a matter of his opinion of course, but judging by his credentials, that opinion is worthy of consideration.
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Re: Theories - Origin of Life

Postby Nick7 » Thu Feb 02, 2012 12:29 am

wbla3335 wrote:...findings of science often differ from the interpretations of those findings, particularly unqualified and prejudged interpretations.

“That's no proof one does not exist, just unlikely to….. have a need to believe in something other than the natural world (c)
all this stuff is also the interpretation. If one is a conscious character in, say, a computer simulation, one cannot possibly objectively and conclusively evaluate through rational thinking how likely or unlikely it is that the reality one exists in is designed or not designed. All one can do is to study the laws governing one's existence in all their enormous complexity and structure. Anything more than that will require breaking the boundaries of space and time, stepping out of the computer simulation and evaluating the situation from aside… something one can’t do (as it stands, at least). Therefore, allocating the role of the designer to “the natural world” also seems to be quite subjective to me, and I don’t see how one can rationally quantify it (likely or unlikely…)
P.s. Personally, I don’t care about naturalistic or non-naturalistic origins of life, universe, etc. I care about the truth (whatever that ends up to be), which assumes providing the podium to the people of diverse opinions, provided they have brains, decent level of education & provided that they do care in this life about something higher than who exactly currently Kim Kardashian sleeps with. Now Scottie is not an evolutionary biologist, agree, but it definitely doesn’t seem like he just hatched into a civilized world from the wilderness of the Polynesian forest either…. And he usually provides links to the opinions of the more-than-qualified individuals. And when he doesn’t, I’m pretty sure you can trace them.
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