RSS 2.0 Feed

» Welcome Guest Log In :: Register

Pages: (6) < 1 2 [3] 4 5 6 >   
  Topic: Abiogenesis discussion thread, No trolls please, we're adults< Next Oldest | Next Newest >  
Alan Fox



Posts: 1365
Joined: Aug. 2005

(Permalink) Posted: Dec. 30 2006,05:18   

Dr Hurd

You appear to agree with Robert Shapiro on the intractability of the OOL problem. Would you agree with him that "RNA world" is not a convincing hypothesis?

Does the "thermal vent" idea appeal?

  
Louis



Posts: 6436
Joined: Jan. 2006

(Permalink) Posted: Dec. 30 2006,07:18   

All,

I haven't deserted this thread, and despite Dr GH's pessimism for its prospects (ironic when considering the critique of Safarti's garbage) when I get a chance I have a "proper" post to make.

Cheers

Louis

--------------
Bye.

  
skeptic



Posts: 1163
Joined: May 2006

(Permalink) Posted: Dec. 30 2006,10:19   

Nor have I, I've been busy with background reading and the holidays.

Lol, if anyone cared.  :D

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Dec. 30 2006,11:29   

Nor have I.
If the library's open today, I plan on checking out Shapiro's book. Holidays are too crazy, though.
Has anyone read the Hazen book, "Gen-e-sis"?

--------------
Must... not... scratch... mosquito bite.

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Dec. 30 2006,17:28   

Good news! I got Shapiro's book, Hazen's, and - for good measure - "Investigations" by Stuart Kauffman (2000) with an adjacent Dewey decimal number and correspondingly related content.

--------------
Must... not... scratch... mosquito bite.

  
"Rev Dr" Lenny Flank



Posts: 2560
Joined: Feb. 2005

(Permalink) Posted: Dec. 30 2006,18:21   

Quote (Dr.GH @ Dec. 30 2006,01:29)
This is how ID really started.  With Thaxton, C. B., Walter L. Bradley, R. L. Olsen
1984 The Mystery of Life’s Origin.  New York: Philosophical Library.

It was not Johnson, Behe, or Dembski.

Yes and no.  Thaxton was probably the first to use the term "intelligent design", but as far as the ID movement itself, it's Johnson who gets the "credit".  

See:  "The Birth of Intelligent Design 'Theory' ", at:

http://www.geocities.com/lflank/designhistory.htm

--------------
Editor, Red and Black Publishers
www.RedandBlackPublishers.com

  
deadman_932



Posts: 3094
Joined: May 2006

(Permalink) Posted: Dec. 30 2006,18:23   

Russell: Excellent, I plan on getting a few of the suggested works here myself.
Being an archaeologist, I didn't get enough background in the basic chem/organic chem/bio/blah,blah, blah classes I took, but I AM fanatically interested in the hard sciences, subscribe to Nature and Science, read constantly and don't mind being guided by more informed people towards a better understanding of the issues. Any other relevant suggested works would be helpful, since you guys already know the territory I'm just entering

--------------
AtBC Award for Thoroughness in the Face of Creationism

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Dec. 30 2006,20:08   

Iris Fry,
2000 "The Emergence of Life on Earth: A Historical and Scientific Overview" Rutgers University Press

This is still the best single cover book available.  This is sad actually, because there is a huge amount of new work that needs to be presented to general readers.

(Hazen has too many personal issues that he lets into his book).  

Shapiro has made a career out of being negative.  Every ship needs an anchor, and Shapiro is the anchor for OOL. That is not for me.

I am in the process of writing up some material, and I have descided to use it as a doctoral proposal.

No need to tell me- I think that it is very weird too: GREs, orals, at my age.  I must be sick. Maybe I'll recover.  But if I am to personally follow this, I need a lab and graduate students have access to labs.

Edited by Dr.GH on Dec. 30 2006,20:10

--------------
"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
deadman_932



Posts: 3094
Joined: May 2006

(Permalink) Posted: Dec. 30 2006,21:18   

Gary: Thanks! I've got a lot of purchasing and reading to do after I recover from this weekend-- I should have demanded book certificates again for Xmas, grrr.  :O

--------------
AtBC Award for Thoroughness in the Face of Creationism

  
Ichthyic



Posts: 3325
Joined: May 2006

(Permalink) Posted: Jan. 04 2007,00:24   

Quote
No need to tell me- I think that it is very weird too: GREs, orals, at my age.  I must be sick. Maybe I'll recover.  But if I am to personally follow this, I need a lab and graduate students have access to labs.


you're a braver man than I, Gunga Din.

I find working with non-profit research groups associated with universities to give me decent access to labs when needed.

the university appreciates NOT having to support your ass through getting another degree, as well.

If you can't find a relevant NGO to work with, you might try making one yourself and going that way.

I did that, and found it to actually be far easier than getting my degree was, that's for sure.

just a thought, and best of luck either way.

--------------
"And the sea will grant each man new hope..."

-CC

  
Alan Fox



Posts: 1365
Joined: Aug. 2005

(Permalink) Posted: Jan. 04 2007,04:40   

Has anyone read Hubert Yockey's book, Hubert P. Yockey, Information Theory, Evolution, and the Origin of Life 2005 Cambridge University Press ISBN 13 978-0-521-80293-2?

His web-site seems to be down but I came across this comment by him in an email published by a critic
Quote
If you send me your postal address I shall send you the Computers & Chemistry paper. That will explain why the recent data on the genomes of human and other organisms provide a mathematical proof of "Darwinism" beyond a reasonable doubt.

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Jan. 04 2007,14:08   

I have read it through once, and will probably make a second pass.  I am not ready to make much about it other than to note that Yockey knows much more about physics and math than about chemistry or biology.  However, he thinks that there is not real difference between math and biology therefore he is (in his imagination) an expert in biology and biochemistry.

Edited by Dr.GH on Jan. 04 2007,14:09

--------------
"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
Steviepinhead



Posts: 532
Joined: Jan. 2006

(Permalink) Posted: Jan. 04 2007,16:16   

I just finished Hazen's Genesis.  It's charming, anecdotal, does provide a very sketchy and spotty overview of the history and breadth of the subject, and spends--in general--way too much time trying to tie Hazen, his colleagues and pals, and his lab to every important ongoing inquiry in the field.

He gives a decent sense of the major positions and disputes in the field, of what we can already feel pretty confident of (much more than what the typical creationists frothing about "abiological" issues would ever admit), and of the many areas that remain to be pursued and pinned down.

Nothing really wrong with any of that--the bit about walking on the tideflats and estimating sand-grain size and coverage, and correlating it all with emergent patterns of sand-ripples is accessible amateur science at its best, and several of the descriptions of "how exactly (read: once over lightly) we went about performing that particular experiment" are entertaining and interesting, you-are-there, accounts.

But.  There's just way too little nitty-gritty chemistry.  Too many photos of people and not enough good illos/diagrams of the concepts.  Science is people and personality-driven, to some large degree, and we all have some level of People-magazine fascination with that aspect of things, but this book had way too much of the rubbing-elbows-with-the-stars and not enough length, detail, and meat.

I wasn't left with a whole lot more "take-home" info than I picked up out of a couple of deDuve's books a decade ago, plus just half-assedly following the topic in pop-science books and mags and news articles since then.

(Hint: You'd do as well, really, to go to the most recent Tangled Web and read the first entry.)

I'm like deadman, I think.  I'm probably not going to be able to follow/keep up with a detailed chemical analysis (and certainly won't have the fonts, etc., to contribute to one, even if I had some of the other background).  But, dammit, I want to SEE it anyway.  And give it a shot.  And pretend to myself I can kinda-sorta follow what's being said.  And ask questions.  And go to the links and the cites if I'm really motivated.

One of the key things that some of the discussions on AtBC and Pharyngula and TO and other such places teaches is that--if you're not a complete pinhead or utterly unteachable/unlearnable (like DaveyDoodles)-- "you"--the broadly-educated, curious layperson--are not incapable of reaching and following the primary literature of science and scholarship, when necessary.

Finding that this was true in a general sense (some earlier, unintegrated experiences from earlier well-done "how to" manuals had intimated the prospect)--which happened to me about ten-twelve years ago, back in the bricks-and-mortar library era--was a personal revelation for me!  One that I attempted to pass onto my then-junior high/high school aged kids while it might still do them some real good, and have attempted--in appropriate social situations--to pass onto other friends, relatives, acquaintances: while we obviously are all, in our specialized world, highly dependent on experts for any number of services and guidance, and while we should not make the mistake that, simply because we can kinda-sorta "follow" what these people are saying, we are instantly no-sweat-involved "one of them," you don't "just" have to take everybody's word for it: if it's important enough to you, you can access and, to some extent, weigh the evidence yourself.

Or at least track an articulate, evidence-weighing discussion/debate among the real scientists well enough to come away with some sense of who's bs-ing you and themselves and who's not.

(This process is, of course, for many reasons we seem unable to get across to the likes of davey, light-years away from going to some single marginalized source of "expert" info and privileging it over every other source in the world.)

Anyway, bring on the nitty-gritty, you real scientists.  Please.  And thanks!

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 05 2007,18:28   

Thanks, Pihhead.
I just finished Shapiro's book, and had much the same reaction. Very little to sink one's teeth into. And, with the added disadvantage of being >20 years old, I can't really recommend it, except for historical interest.
It does have some interesting history about Lysenkoism in the Soviet Union, which turns out to have a significant impact on the whole field. Oparin, who is basically the father of the discipline was a Lysenkoist.
I was about to start Hazen, but in light of Stevie P's review, I think I'll skip straight to Kauffman's "Investigations". I do note, though, that the foreword to Hazen's book was written by David Deamer, one of my professors in graduate school whom I especially admired.

--------------
Must... not... scratch... mosquito bite.

  
Steviepinhead



Posts: 532
Joined: Jan. 2006

(Permalink) Posted: Jan. 05 2007,20:04   

Deamer comes off well in Hazen's book.

Again, I enjoyed the book, as far as it went.  It just wasn't the toothsome, incisive chomp at the latest data that I was hoping it would be.

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 05 2007,21:53   

A quick leafing through the book tells me it will be more "toothsome" than the Shapiro book, though.

Maybe to really get into the nitty gritty, we'll have to read recent issues of "Origins of Life and Evolution of the Biosphere", or perhaps some of the 128 references listed by Louis in his thread opener.

I feel like I need a little big-picture orientation, though, before I can put into proper perspective questions like "is cyanoacetylene prebiotic?".

--------------
Must... not... scratch... mosquito bite.

  
MichiganRuss



Posts: 2
Joined: Jan. 2007

(Permalink) Posted: Jan. 10 2007,18:26   

Glad I found this thread.

OOL research is a fascinating topic area for me.

I think there are numerous directions from which to approach it that could offer incite.  Incite might be our best we can hope for in the short term since we do lack the exact details of the primary chemistries on the early earth.  Fortunately, incite can offer great directionality to further inquiry if that incite stimulates curiosity to the point of goading a researcher into following a line of inquiry long enough for it to bear fruit.

In considering OOL, since we are dealing with unknown processes and conditions, we are essentially working in the abstract.  We are basically attempting to ferret out the nature of the pre-cellular material processing.  When we talk of specifics - what reaction kinetics are necessary for a specific molecular species to predominate in a solution, for instance - we need expert knowledge of chemistry.  However, at this point, even the chemistry experts are looking for a guide in the form of a plausibility argument for how the transition to cellular life occurred.  In this process of creative guessing, anyone with the ability to combine the basic capabilities of chemical species - get longer, get shorter, fold, match shapes, make reactions easier, make reactions harder, prefer reacting with some other chemicals, be stable, be unstable, among others - in, perhaps uncharacteristic, tinker toy kinds of ways, potentially has the ability to offer incite into the origin of life.  So, to those of you who have prefaced your posts with self-deprecating comments about your understanding of chemistry or the current state of OOL research I say start looking at it in a more creative, more abstract way.  The current state of OOL research is more about looking for a way to proceed than it is about discovering the answer.  Realistically, the spark that illuminates the most promising path forward may well be ignited by observing soap bubbles or watching a kite line entangled in a tree.

The sciences like chemistry and physics have demonstrated for us that the chemistry of living things is not distinct from the chemistry of non-living things.  This provides us with all the reason we need to pursue the earthly - as opposed to pre-existing life riding to earth on a comet - origin of life as a legitimate discipline with hope of success.  That progress toward the goal of understanding the OOL on this planet might be slow can be understood and accepted when we consider how ill-prepared we still are, even in the scientific community, to deal with the level of complexity associated with living things.  When I say complexity, I simply mean the capacity to simultaneously account for the behavior of a large number interacting entities.

The difficulty of predicting behaviors becomes apparent when we look at three-atom water, for instance.  Water is composed of one oxygen bonded to two hydrogen atoms.  The characteristics of water are "emergent" properties of the combining of those three atoms in that exact way. The properties of molecular water are very different from those of molecular hydrogen, very different from those of molecular oxygen, and very different from any mixture of the two.  Then, too, the specific configurations of the atomic species in water itself make for still different emergent properties of water as a gas, as a liquid or as a solid.

Just as water is an emergent property of oxygen combined with hydrogen in exact proportions under specific conditions, life, too, is a product of emergence - emergence at many levels.  At the atomic level, life depends on the emergent properties of sodium and calcium ions interacting with water.  At the molecular level life depends on characteristics of water, amino acids, nucleic acids, and glucose to name a few.  At the macromolecular level lipids,  DNA, RNA, and proteins for instance, all exhibit properties quite distinct from their component sub units. Emergence continues through the sub-cellular, organelle, cellular, organ, organ system, organism, society, and ecosystem levels.

To me, this is a fascinating topic and I hope others find it as engaging as I do.
----------------------

For the purposes of discussion, here, what do we consider life?  Are self-replicating molecular species alive?  Is a cell wall required?  Can any series of reactions be considered living if they are not enclosed in a cell wall but still result in the production of a specific molecule?  Are we looking for literal inheritability in that a "parent" creates a duplicate "daughter" genetic molecule and passes it to its progeny?  Is a microsphere alive if it reproduces simply by swelling and breaking in half?

Which comes first metabolism or inheritability?  Can they be the same thing?

Thanks,

MichiganRuss

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 10 2007,21:41   

The Kauffman book, "Investigations", is, indeed, all about abstractions, not the specifics of any chemical hypothesis. (I'm still reading, though. Not ready for a full report).

A lot is made, especially by creationists, of how well the Miller-Urey experiment does or does not represent anything like Earth's atmosphere 4 bya. But there's not much point in trying to get "more realistic" conditions, since the Earth's surface is not and never was homogeneous. Did life first emerge near an undersea volcanic vent? The surface of a pond? What temperature? No way to know. It may have had its start in a very atypical environment. It's in the nature of life to break out of micro-environments and expand into - I like this term of Kauffman's - "the adjacent possible". That makes me think that, however much fun it is to entertain various chemical hypotheses, no consensus is likely to emerge in the foreseeable future.

Maybe, on the other hand, we can intelligently assess more abstract treatments of the subject. Like, are there any compelling reasons to suppose a nucleic-acid first scenario? Or how could a "metabolism-only" scenario have the necessary self-replicating mechanisms to qualify as "life"?

(For the purposes of this discussion, I guess the definition of "life" in my mind is something like a self-replicating entity that is genetically related to me, my cat, pond scum, E. coli...)

Anyway, whatever the actual sequence of events (replicating, "naked" nucleic acids subsequently, somehow, acquiring cells; cells somehow replicating before acquiring nucleic acids?) DNA had to have its own origin somewhere, somewhen, somehow - likely as a modified RNA. And RNA had to have its origin. The genetic code had to have its origin...

Any one of these origins would probably merit a more substantial discussion than The Big One, the ultimate origin of Life Itself. Unfortunately, even there I predict there's not going to be much of a consensus in my lifetime.

--------------
Must... not... scratch... mosquito bite.

  
skeptic



Posts: 1163
Joined: May 2006

(Permalink) Posted: Jan. 10 2007,22:06   

With all my reading in the past couple weeks I've been kicking around an idea and since MichiganRuss has posed the question I'll let it rip.  Just to caution it is fairly radical.  What if life is DNA, RNA and proteins?

I don't mean composed of but actually that is the only configuration that is life.  We're looking at scenarios of a primitive self-replicating molecule but we have no evidence that such a molecule can exist or ever has.  Just to be clear I'm not talking about crystals or polymers but a molecule that truely facilitates its own replication.  In fact, every form of life on the planet meets this criteria and we even have cases that partially meet this criteria and we do not consider them "alive" (viruses and prions).  This could be proof of common descent or just more simply that all life requires this configuration to be alive.  Even in our search beyond the planet we're looking for life similar to what we have here.  Would we even recognize life that wasn't compsed of DNA, RNA and proteins?

Just a thought and certainly not a popular one but what really got it going for me is the fact that there are no other forms (or never have been as far as we know) of life on the planet.  Wouldn't it be reasonable to assume that in the past 3-4 billion years something new would have developed from the DNA, RNA, protein framework and we'd see a branch that was similar but different.  Wouldn't evolution and selection nearly guarantee this outcome unless such a configuration just flat out didn't function?

Anyway, thought I'd show you guys what this background reading had done to my already crazy brain.

  
Louis



Posts: 6436
Joined: Jan. 2006

(Permalink) Posted: Jan. 11 2007,03:40   

All, I'm collecting references for Big Post, please bear with me during this busy time!

Skeptic,

There are examples of self replicating non nucleotide, non protein chemical systems and molecules. Check out those Rebek refs I provided right at the start. Also, don't get as hung up on the semantics of "alive" or "life" like you're appearing to. The semantics aren't what's important.

Quote
Just a thought and certainly not a popular one but what really got it going for me is the fact that there are no other forms (or never have been as far as we know) of life on the planet.  Wouldn't it be reasonable to assume that in the past 3-4 billion years something new would have developed from the DNA, RNA, protein framework and we'd see a branch that was similar but different.  Wouldn't evolution and selection nearly guarantee this outcome unless such a configuration just flat out didn't function?


Not necessarily no. First and foremost the reason abiogenesis is tough to find certain types of "fossil" evidence for, and one reason a plurality of different replicating systems don't exist in other organisms is this: we living organisms have a word for things like that: food.

Second you have it bass ackwards. the nucleotide/protein/carbohydrate (everyone forgets the glycome for some reason. Very silly) system we have now is the most successful one that DID evolve, not the only possible one that could have evolved. One of the things we are trying to find out is what other systems could have developed, mainly because they could give us clues to the precise pathways taken to the current point. Never forget Mother Nature, whilst coy and cunning, is also cheap. If it ain't broke there's no need to fix it. At some point there was a replicating system that worked well, perhaps it was in isolation, perhaps it was first amongst equals, perhaps it was an out an out winner, perhaps it was a lucky underdog, this much we don't know. What we DO know is that it occured way in the past (i.e. it was an early event, possibly one prior to the evolution of more complex organisms), we know this because from the bottom of the ocean to the top of the highest mountain every organism encountered uses the same system of transferring inheritable information to the next generation. There are variations, but the underlying "basic" chemistry is the same. (Obviously this is the shorthand, potted version) We know that the most parsimonious explanation for this is common descent, i.e. that modern organisms have evolved from this Ur-replicator, or various Ur-replicators relatively closely aligned. The problem we have (as has been stated many times on this thread) is that we don;t know what specific path was taken nor which "hurdles" were passed in what order. What we DO know is what the likely hurdles are/were, what some mechanisms and paths that could have been taken are, and roughly what is needed to make those paths. To use a magic analogy it's like the guess the card trick done badly. We know that a card is involved (woohoo!;), we even have some idea of whether it's a black card or red card. We're not sure of the suit, but interestingly we know that it's a picture card. See what I mean?

Louis

Louis

--------------
Bye.

  
Ichthyic



Posts: 3325
Joined: May 2006

(Permalink) Posted: Jan. 11 2007,15:33   

Uh, Loius,

Since Sal constantly conflates abiogenisis and the ToE, I invited him to participate in your thread.

*ducks behind bar*

...but it's really unlikely he'll bother; he hates this place as he always gets shredded and has to go into retreat to put his mental blocks back in place.

Just thought I'd give you a head's up, and apologize ahead of time for any collateral damage that might occur should he actually decide to spend time here.

--------------
"And the sea will grant each man new hope..."

-CC

  
Louis



Posts: 6436
Joined: Jan. 2006

(Permalink) Posted: Jan. 11 2007,16:04   

Icthyic,

Oh now that's just mean. Are you not satisfied with the tards we already have?

When I was an undergrad a friend of mine and I instigated the "Mormon Wars". We'd go to the high street bright and early on a Saturday afternoon, and sign ourselves up for visits by mormons and JWs using the other guy's identity and address. We'd specify an early visit. It got slightly out of hand.

You have instigated their 21st century equivalent: "Tard Wars". You do realise that I am now going to have to go undercover and get Duane Gish to come to your house or arrange for you to be an authorised visitor for Hovind don't you? As if I'm not busy enough already.

Louis

--------------
Bye.

  
Ichthyic



Posts: 3325
Joined: May 2006

(Permalink) Posted: Jan. 11 2007,16:20   

I see I shouldn't have said anything.

curse my honesty!

oh well, at least it will make life interesting.

I still think Sal won't bother, but if he does, you're welcome to take your best shot.

--------------
"And the sea will grant each man new hope..."

-CC

  
Louis



Posts: 6436
Joined: Jan. 2006

(Permalink) Posted: Jan. 11 2007,17:12   

{bring bring, bring bring}

"Hello is that Duane? Hi it's your devoted disciple here.I don't suppose you could do me a favour could you....."

"....You could? Oh that's super! Naked you say? Even better. The address you need is......"

"Yup 5 am Saturday morning will be fine."

Mwah ha haaa.

{twirls moustache}

Louis

--------------
Bye.

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Jan. 11 2007,17:21   

I put this together almost 2 years ago, and it need to be updated.  But, I think that you can still get a quick start on the relevant literature in primary journals.

Darwin's first edition of The Origin of Species made no particular mention of the origin of life. He does make some general observations in the conclusion of the sixth edition published in 1872. He writes,
 
Quote
"I believe that animals are descended from at most only four or five progenitors, and plants from an equal or lesser number.

Analogy would lead me one step further, namely, to the belief that all animals and plants are descended from some one prototype. But analogy may be a deceitful guide.  Nevertheless all living things have much in common, in their chemical composition, their cellular structure, their laws of growth, and their liability to injurious influences."

And,
 
Quote
"No doubt it is possible, as Mr. G.H. Lewes has urged, that at the first commencement of life many different forms were evolved; but if so, we may conclude that only a very few have left modified descendants."

And a bit later, "Authors of the highest eminence seem to be fully satisfied with the view that each species has been independently created. To my mind it accords better with what we know of the laws impressed on matter by the Creator, that the production and extinction of the past and present inhabitants of the world should have been due to secondary causes, like those determining the birth and death of the individual. When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Cambrian system was deposited, they seem to me to become ennobled."


The final sentence in the first edition, "There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved." was slightly modified in the Sixth to clearly indicate that the "Creator" was responsible for the origin of life. Some scholarly studies claim that Darwin regretted making this concession to his publishers.

The general interest books on the origin of life (OOL) typically start with a lengthy discussion of the historical theories of life. Beginning with the Greeks and working our way toward the present, there are three most significant events: the invention of the microscope, the synthesis of urea, and the experiment by Pasteur in 1862.

All the early thought on the origin of life can be reduced to a theory of spontaneous generation of life, or the creation of life by supernatural external agency. The invention, and improvements to the microscope between 1590 and 1674 CE profoundly changed mankind's conception of life and its complexity. This seemed to many as support for the spontaneous generation of life notion, as these microscopic life forms were thought as the simple "seed" for latter complex life. Anton van Leeuwenhoek's discovery of sperm also added to this "support" for the spontaneous generation theory.

There was also the thought that the organic "stuff" of life was completely different from "inorganic" or mineral matter. Known as "vitalism," this concept was shown to be false by Wühler in 1832 when he made urea, a "live" compound, from inorganic stock chemicals.

The most popular argument that creationists like to cite against results from modern origin of life research is that Pasteur demonstrated that the "spontaneous generation" theory was invalid. However, we should be quite clear that the Pasteur experiments showed that complex life forms do not form spontaneously. They did not address the origin of life as we currently understand the concept.

The growing interest in the search for extra-terrestrial life as fueled more productive research on OOL in the last 15 years than has ever been done in history. The Emergence of Life on Earth: A Historical and Scientific Overview by Iris Fry, (2000 Rutgers University Press), is the best general reader book available on the topic. Even though it is only 5 years old, a second edition is warrented to bring her presentation up to date.

There are quite a list of specifics that go into origin of life research, and very few research groups go far with more than a few. Just to list the key areas as I see them:

1) Composition of the Hadean/early Archean atmosphere.

The key reference(s) here is:

Genda, Hidenori & Abe, Yutaka
2003 “Survival of a proto-atmosphere through the stage of giant impacts: the mechanical aspects" Icarus 164, 149-162 (2003).

Holland, Heinrich D.
1984 The Chemical Evolution of the Atmoshphere and Oceans, Princeton Series in Geochemistry Princeton University Press

Holland, Heinrich D.
1999 “When did the Earth’s atmosphere become oxic? A Reply." The Geochemical News #100: 20-22 (see Ohmoto 1997 )

Kasting, J. F., J. L. Siefert,
2002 “Life and the Evolution of Earth's Atmosphere" Science 296:1066

Pepin, R. O.
1997 Evolution of Earth's Noble Gases: Consequences of Assuming Hydrodynamic Loss Driven by Giant Impact Icarus 126, 148-156 (1997).

There are a few others, but anyone reading those above will get the basics. The result is that there was a reducing atmosphere, and ocean system with highly reducing oases. A recent paper

Rosing, Minik T. and Robert Frei
2003 U-rich Archaean sea-floor sediments from Greenland – indications of >3700 Ma oxygenic photosynthesis" Earth and Planetary Science Letters, online 6 December 03

presents data that suggest there were very early oxygenic life forms in marine basins that most likely (to me anyway) were wiped out.

So, with a reduced atmosphere and ocean system, a shallow, hot crust and a UV rich, "cold" sun, we can ask the next question which is,

2) What was the source for "organic" molecules?

The classic paper was of course Stanley Miller's 1953 paper

Miller, Stanley L.,
1953 “A Production of Amino Acids Under Possible Primitive Earth Conditions&#65533;? Science vol. 117:528-529

With a bit more information included in:

Miller, Stanley, Harold C. Urey
1959 “Organic Compound Synthesis on the Primitive Earth&#65533;? Science vol 139 Num 3370: 254-251

Miller showed that a very simple set up that mimicked some key asspects of the early Earth could rapidly produce amino acids, among other things.

This result has been one of the most often repeated (and confirmed) experiments I have ever encountered. In spite of this, creationists regularly claim that it is invalid. Jonathan Wells, a fellow of the creationist "Discovery Institute" claims to have refuted the Miller/Urey experiment (and all of what he called Darwinist "icons."

But, the atmosphere is not the only synthesis location. For example

Amend, J. P. , E. L. Shock
1998 “Energetics of Amino Acid Synthesis in Hydrothermal Ecosystems&#65533;? Science Volume 281, number 5383, Issue of 11 Sep , pp. 1659-1662.

Blank, J.G. Gregory H. Miller, Michael J. Ahrens, Randall E. Winans
2001 “Experimental shock chemistry of aqueous amino acid solutions and the cometary delivery of prebiotic compounds&#65533;? Origins of Life and Evolution of the Biosphere 31(1-2):15-51, Feb-Apr

Chyba, Christopher F., Paul J. Thomas, Leigh Brookshaw, Carl Sagan
1990 "Cometary Delivery of Organic Molecules to the Early Earth" Science Vol. 249:366-373

Engel, Michael H., Bartholomew Nagy,
1982 "Distribution and Enantiomeric Composition of Amino Acids in the Murchison Meteorite", Nature , 296, April 29, , p. 838.

Matthews CN.
1992 Hydrogen cyanide polymerization: a preferred cosmochemical pathway. J. Br. Interplanet Soc. 45(1):43-8

Schoonen, Martin A. A., Yong Xu
2001 “Nitrogen Reduction Under Hydrothrmal Vent Conditions: Implications for the Prebiotic Synthesis of C-H-O-N Compounds&#65533;? Astrobiology 1:133-142

So amino acids are easy and plentiful on a pre-life (abiotic) Earth.

But, we need more than just amino acids- sugars, nucleic acids, and lipids are also needed. I'll take those next.

Let's see.. I guess this is

2a) amino acids
2.b) sugars


Why do we need sugars? Well, the biggest reason is that without five carbon sugar our building life form can't make a "memory" like RNA or DNA. I'll get to the details later. First, where are the sugars?

Weber AL.
1997 Prebiotic amino acid thioester synthesis: thiol-dependent amino acid synthesis from formose substrates (formaldehyde and glycolaldehyde) and ammonia. Origins of Life and Evolution of the Biosphere 28: 259-270.

{I know the title says "amino acid" but sugar is in there. Hint: formose is a kind of sugar. }

Cooper, George, Novelle Kimmich, Warren Belisle, Josh Sarinana, Katrina Brabham, Laurence Garrel
2001 Carbonaceous meteorites as a source of sugar-related organic compounds for the early Earth Nature 414, 879 - 883 (20 Dec 2001) Letters to Nature

Cody, George D., Nabil Z. Boctor, Timothy R. Filley, Robert M. Hazen, James H. Scott, Anurag Sharma, Hatten S. Yoder Jr.
2000 “Primordial Carbonylated Iron-Sulfur Compounds and the Synthesis of Pyruvate"  Science v.289 : 1337-1340

Sephton, Mark A.
2001 Meteoritics: Life's sweet beginnings? Nature 414, 857 - 858 (20 Dec ) News and Views

Ricardo, A., Carrigan, M. A., Olcott, A. N., Benner, S. A.
2004 "Borate Minerals Stabilize Ribose" Science January 9; 303: 196 (in Brevia)

Stanley Miller, and collegues suggested an earlier substitute for sugar in :

Lazcano, Antonio, Stanley L. Miller
1996 “The Origin and Early Evolution of Life: Prebiotic Chemistry, the Pre-RNA World, and Time&#65533;? Cell vol 85:793-798

Nelson, K. E., M. Levy, S. L. Miller
2000 “Peptide nucleic acids rather than RNA may have been the first genetic molecule" PNAS-USA v.97, 3868-3871

There are many more articles, but the bottom line reads "We got sugar."

OK, I'll do nucleic acid bases next. There aren't many that are used on Earth, just five.

There are a large number of creationist's books and web sites that claim there is some huge stability problem with nucleic acid base synthesis. This is a nice demonstration of how creationists copy eachother, since there are only a handfull of creationists with the education to even understand what this means. None that I know of have actually done research in the directly relevant area. Their claims generally can be traced back to a legit scientist, Robert Shapiro. Two of his representitive publications are:

Shapiro, Robert
1986 "Origins: A Skeptics Guide to the Creation of Life on Earth" New York: Summit Books

Shapiro, Robert
1999 Prebiotic Cytosine Synthesis: A Critical Analysis and Implications for the Origin of Life. Proceedings of the National Academy of Science 96 (8): 4396 *Side reactions make cytosine synthesis unlikely, but see Nelson et al (2001)

The 1986 book is very out of date, and very popular with creationists.

The 1999 Shapiro paper has also been answered. Levy and Miller raise a question of their own in:

Levy, M and Miller, S.L.,
1998 The stability of the RNA bases: Implications for the origin of life, Proc. Natl. Acad. Sci. USA 95(14):7933–38,

But, like superior scientists, they answer the questions they raise.

The following are a selections of research articles that address the pre-biotic origin of nucleic acid bases:

Fuller, W. D., Sanchez, R. A. & Orgel, L. E. Studies in prebiotic synthesis. VI. Synthesis of purine nucleosides. J. Mol. Biol. 67, 25-33 (1972).

Robertson, MP, Miller SL.
1995 An efficient prebiotic synthesis of cytosine and uracil. Nature 375, 772 - 774 ()

Nelson K.E., Robertson M.P., Levy M, Miller S.L.
2001 Concentration by evaporation and the prebiotic synthesis of cytosine. Orig Life Evol Biosph Jun;31(3):221-229

For our fans following along at home, there are aspects of nucleoside synthesis in the earlier referenced papers as well.

So, we got plenty of nucleic acid bases.

2c) lipids.

Lipids are the stuff of membranes, they are what keeps inside in, and outside out.  Today they are made by simple cells and moved up the food chain. So where did they come from 3.7 billion years (or so) ago?

One major source seems to be from meteors.

Deamer, D. W.
1985. Boundary structures are formed by organic components of the Murchison carbonaceous chondrite. Nature 317:792-794.

Deamer, D. W., and Pashley, R. M.
1989. Amphiphilic components of carbonaceous meteorites. Orig. Life Evol. Biosphere 19:21-33.

Krishnamurthy, R., Pitsch, S. & Arrhenius, G. 1999 Mineral induced formation of pentose-2,4-bisphosphates. Origins Life Evol. Biosph. 29, 139-152 ().

Dworkin, Jason P., David W. Deamer, Scott A. Sandford, and Louis J. Allamandola
2001 “Self-assembling amphiphilic molecules: Synthesis in simulated interstellar/precometary ices&#65533;? PNAS 98: 815-819

Pizzarello, Sandra, Yongsong Huang, Luann Becker, Robert J. Poreda, Ronald A. Nieman, George Cooper, Michael Williams
2001 “The Organic Content of the Tagish Lake Meteorite&#65533;? Science, Vol. 293, Issue 5538, 2236-2239, September 21, 2001

Segre' D., Ben-Eli D. Deamer D. and Lancet D.
2001 “The Lipid World&#65533;? Origins Life Evol. Biosphere 31, 119-145.

So now that we got 'em, what do they do once they are on Earth?

They make things.

Martin M. Hanczyc, Shelly M. Fujikawa, and Jack W. Szostak
2003 Experimental Models of Primitive Cellular Compartments: Encapsulation, Growth, and Division Science October 24; 302: 618-622. (in Reports)

D.W. Deamer
1997 "The First Living Systems - A Bioenergetic Perspective", ; Microbiology and Molecular Biology Reviews, 61(2): 239; June

Chakrabarti, A.C., R.R. Breaker, G.F. Joyce, & D.W. Deamer
1994 Production of RNA by a Polymerase Protein Encapsulated within Phospho-Lipid Vesicles Journal of Molecular Evolution 39(6): 555-559 ( December)

Khvorova A, Kwak YG, Tamkun M, Majerfeld I, Yarus M.
1999. RNAs that bind and change the permeability of phospholipid membranes. Proceedings of the National Academy of the Sciences USA 96:10649-10654.

Yarus M.
1999. Boundaries for an RNA world. Current Opinion in Chemical Biology 3:260-267.

Walter P, Keenan R, Scmitz U.
2000. SRP-Where the RNA and membrane worlds meet. Science 287:1212-1213.


So far, we have amino acids, riobose and/or other 5 carbon sugar substitutes (pentoses), we have lipid membranes which encapsulate mineral particles and "organic" molecules.  This is without any needed "interventions" and is purely the result of ordinary chemistry.

But, there are more things that need to happen before there is life on Earth.

Point 3) formation of complex systems

3a) Chirility


Pastuer discovered that most amino acids came in two forms which can be identified by how they refract light. We label theses L- (for levo or left) adn D- (for dextro, or right). The interesting thing is that life on Earth uses the L form of amino acids, and hardly ever uses the D- form. A solution of just one form is called "chiral" and a mix of forms about 50/50 is called racimic. The kinds (L or D) are called enantomers.

The nucleic acid bases I mentioned earlier are also found in L- and D- forms, only in this case life on Earth only uses the D- form.

Creationists like to present this as a profound mystery that is supposed to "prove" that they are correct. I want to mention a neat instance where both left and right amino acids are used in a living thing. It is very rare, but it does happen. Next time a creationist claims to be an "expert" and that amino acid chirility "proves" something supernatural, you can gob-smack-em. The protein is called Gramicidin A and it has 8 L-amino acids, 6 D-amino acids, and one glycine which is an amino acid that is neither L- or D- in its structure. I have found that even many biologists will bet an "adult beverage" that all proteins are exclucive L- amino acids.

Before we go forward another couple of basic chemical facts need to be added to the discussion. First, L- amino acids will randomly convert to D- amino acids over time, and D- forms will convert to L- forms. This is called "racimization" becuse eventually you will end up with equal amounts of L- and D- amino acids. The rate that this occurs at varies with the amino acid, and its surroundings. The fastest conversion happens to amino acid molecules all by themselves in hot water. Under cold, dry conditions when the amino acids are attatched to one another, or better yet, if they are also attatched to a mineral or metal atom, racimization can be very slow. Very, very slow.

This means that if there is even a tiny advantage one way or the other, the favored form will become the dominant form. The advantage comes from a surprising direction: outer space.

Cronin, J. R. & Pizzarello, S.,
1999. Amino acid enantomer excesses in meteorites: Origin and significance. Advances in Space Research 23(2): 293-299.

Service, RF,  
1999. Does life's handedness come from within? Science 286: 1282-1283.

Antonio Chrysostomou, T. M. Gledhill,1 François Ménard, J. H. Hough, Motohide Tamura and Jeremy Bailey
2000 "Polarimetry of young stellar objects -III. Circular polarimetry of OMC-1" Monthly Notices of the Royal Astronomical Society Volume 312 Issue 1 Page 103 - February

Michael H. Engel and Bartholomew Nagy,
1982 "Distribution and Enantiomeric Composition of Amino Acids in the Murchison Meteorite", Nature , 296, April 29, , p. 838.

Jeremy Bailey, Antonio Chrysostomou, J. H. Hough, T. M. Gledhill, Alan McCall, Stuart
Clark, François Ménard, and Motohide Tamura
1998 Circular Polarization in Star- Formation Regions: Implications for Biomolecular Homochirality Science 1998 July 31; 281: 672-674. (in Reports)

Chyba, Christopher F.
1997 Origins of life: A left-handed Solar System? Nature 389, 234- 235 (18 Sep 1997)

Engel, M. H., S. A. Macko
1997 Isotopic evidence for extraterrestrial non- racemic amino acids in the Murchison meteorite. Nature 389, 265 - 268 (18 Sep) Letters to Nature

That should do for that. The next question is can the advantage of L- amino acids be conserved in the formation of more complex molecules called "peptides?" Yep.

Schmidt, J. G., Nielsen, P. E. & Orgel, L. E. 1997 Enantiomeric cross-inhibition in the synthesis of oligonucleotides on a nonchiral template. J. Am. Chem. Soc. 119, 1494-1495

Saghatelion A, Yokobayashi Y, Soltani K,
Ghadiri MR,
2001"A chiroselective peptide replicator", Nature 409: 797-51, Feb

Singleton, D A,& Vo, L K,
2002 “Enantioselective Synthsis without Discrete Optically Active Additives&#65533;? J. Am. Chem. Soc. 124, 10010-10011

Yao Shao, Ghosh I, Zutshi R, Chmielewski J.
1998 Selective amplification by auto- and cross-catalysis in a replicating peptide system. Nature. Dec 3;396(6710):447-50.

And there seems to be other L- selction advantages as well. For example:

Hazen, R.M., T.R. Filley, and G.A. Goodfriend.
2001. Selective adsorption of L- and D-amino acids on calcite: Implications for biochemical homochirality. Proceedings of the National Academy of Sciences 98 (May 8):5487.

So chirility doesn't seem to be a big problem. This is far different from the way creationists present this. They cite a few out of date reports and then falsely claim that chiral life is impossible by natural means.

But what about the nucleic acid bases? A new paper has just laid out the next step:

Ricardo, A., Carrigan, M. A., Olcott, A. N., Benner, S. A.
2004 "Borate Minerals Stabilize Ribose" Science January 9; 303: 196 (in Brevia)

Pizzarello, Sandra, Arthur L. Weber
2004 Prebiotic Amino Acids as Asymmetric Catalysts Science Vol 303, Issue 5661: 1151, 20 February 2004

It turns out that the selective advatage of L- amino acids will force the selection of D- nucleic acids, and the whole reaction can proceed under common, natural conditions.

Well, we have all the pieces. Our planet was formed from massive collisions of planetoids that had undergone independent evolution and weathering which retained much of their atmospheres to add to the growing planet Earth. We have amino acids, sugars, nucleic acid bases, lipids and minerals under an anoxic to reducing atmosphere and ocean with a thin hot crust and a UV rich cold Sun. Plus, remember that the Moon is closer and orbiting faster producing massive tidal flows compared to modern times.

Will these combine to make any thing?

Yep, they sure will:


Ferris JP, Hill AR Jr, Liu R, and Orgel LE. (1996 May 2). Synthesis of long prebiotic oligomers on mineral surfaces [see comments] Nature, 381, 59-61.

Lee DH, Granja JR, Martinez JA, Severin K, Ghadri MR.
1996 “A self-replicating peptide." Nature Aug 8;382(6591):525-8

A.C. Chakrabarti, R.R. Breaker, G.F. Joyce, & D.W. Deamer
1994 Production of RNA by a Polymerase Protein Encapsulated within Phospho-Lipid Vesicles Journal of Molecular Evolution 39(6): 555-559 (1994 December)

Smith, J.V.
Biochemical evolution. I. Polymerization on internal, organophilic silica surfaces of dealuminated zeolites and feldspars Proceedings of the National Academy of Sciences of the United States of America 95(7): 3370-3375; March 31, 1998

Smith, J.V., Arnold, F.P., Parsons, I., Lee, M.R.
Biochemical evolution III: Polymerization on organophilic silica-rich surfaces, crystal-hemical modeling, formation of first cells, and geological clues Proceedings of the National Academy of Sciences of the United States of America 96(7): 3479-3485; March 30, 1999

Blochl, Elisabeth, Martin Keller, Gunter Wächtershäuser , Karl Otto Stetter
1992 “Reactions depending on iron sulfide and linking geochemistry with biochemistry" PNAS-USA v.89: 8117-8120

Dyall, Sabrina D., Patricia J. Johnson
2000 “Origins of hydrogenosomes and mitochondria: evolution and organelle biogensis." Current Opinion in Microbiology 3:404-411

Huber, Claudia, Gunter Wächtershäuser
1998 “Peptides by Activation of Amino Acids with CO on (Ni,Fe)S Surfaces: Implications for the Origin of Life&#65533;? Science v.281: 670-672

Imai, E., Honda, H., Hatori, K., Brack, A. and Matsuno, K.
1999 “Elongation of oligopeptides in a simulated submarine hydrothermal system“ Science 283(5403):831–833.

Lee DH, Severin K, Yokobayashi Y, and Ghadiri MR,
1997 Emergence of symbiosis in peptide self- replication through a hypercyclic network. Nature, 390: 591-4

Someone asked why I posted so many references.

There are several reasons. First, that is how science is done, we build on the work of others.

Second, when we use referenced data to make a point clear we state the source of our information up front. Anyone can read these papers. If they want, they can argue that I have misread the article, or that the article itself has been refuted by more up-to-date
information.

Third, a common creationist claim is that there is no valid research on the origin of life, or that the research done is inconclucive. The references I have cited are evidence that these claims are false.

Fourth, except for some historical references, my sources are mostly less than 10 years old. This is in direct contrast to the selective use by creationist writers such as Jon Sarfati, or Jon Wells, who use a few out of date and refuted articles to puff up their nonsense.

So, there you have it.

--------------
"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
qetzal



Posts: 308
Joined: Feb. 2006

(Permalink) Posted: Jan. 11 2007,22:42   

Great post, Dr. Hurd!

One minor quibble, which I only point out so you can correct when you do an update. The section on chirality mentions nucleic acid bases in several places. The bases themselves are not chiral, of course. It's the attached sugars that are chiral. (The term for a base plus a sugar is a nucleoside. If a phosphate is also attached, it's a nucleotide.)

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Jan. 12 2007,01:18   

Quote (qetzal @ Jan. 11 2007,22:42)
Great post, Dr. Hurd!

One minor quibble, which I only point out so you can correct when you do an update. The section on chirality mentions nucleic acid bases in several places. The bases themselves are not chiral, of course. It's the attached sugars that are chiral. (The term for a base plus a sugar is a nucleoside. If a phosphate is also attached, it's a nucleotide.)

D'oh (or however Homer Simpson's standard line is written)

You are correct- my bad.

--------------
"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
Louis



Posts: 6436
Joined: Jan. 2006

(Permalink) Posted: Jan. 12 2007,03:19   

Dr GH,

Thanks very much indeed for that excellent series of references and explanations. Great contribution.

Louis

P.S. I've just taken out a personal subscription to "Origin of Life and the Evolution of Biospheres", a really excellent Springer Journal. So expect my next set of refs to be "midly" biased!

--------------
Bye.

  
MichiganRuss



Posts: 2
Joined: Jan. 2007

(Permalink) Posted: Jan. 13 2007,23:12   

Dr. GH, great post, lots of great stuff.

<blockquote>
The protein is called Gramicidin A and it has 8 L-amino acids, 6 D-amino acids, and one glycine which is an amino acid that is neither L- or D- in its structure. I have found that even many biologists will bet an "adult beverage" that all proteins are exclucive L- amino acids.
</blockquote>

What cried out to me for comment was the mixed L and D enantiomers in the Gramicidin A structure.

The Gramicidin structure with chirality is shown at http://en.wikipedia.org/wiki/Gramicidin

Does anybody here know much about Gramicidin A synthesis?  Is the synthesis done from actual L and D amino acids or does the pathway synthesize the resultant mixed L and D structure from non-amino acid pre-cursors?  Is much known about the genetics of the pathway?  Clearly, I've got some digging to do!

-------------------------

One conception of the origin of life that truly fascinates me is the idea of self-replicating microspheres.  I guess we could envision a  microscopic bubble which forms automatically through simple mechanical actions like waves coming ashore or bubbles created in an underwater hot vent.  From several sources I've read pieces discussing the self-replicating nature of the spheres being due to the specific structure of the enclosing membrane.  I've often wondered if the structure of the membrane could be a means of heritability.  If the process of reproduction of the spheres was simply absorbing materials from the environment until the mechanical strain on the membrane was such that it split, then the initial structure of the mechanically formed sphere could determine rate of absorption and so, rate of reproduction.

Membranes vary greatly as to the nature of their permeability, that is, what may pass through the membrane - size of species permitted through, chemical nature of species passed, orientation of the passed species, shape of passed molecules, flexibility, hydrogen bonding characteristics, among others.  The specific structure of the membrane, effects the contents of the sphere, rates of absorption, etc and thus the rate at which the volume of the contents surpass the divide threshhold.  I'm curious about the membrane itself, with its selecting capabilities, being the "genetic code" for the sphere. If the membrane could selectively take up ambient materials to perform a reproductive cycle with reasonable fidelity, would the flaws in the membrane constitute a form of variability on which natural selection could get a foothold?

Its appeal to me is its simplicity: a crude bubble taking as long to reproduce as its environment and its membrane characteristics necessitate - months or years or even decades are conceivable; simple energy system - using chemical gradients to power the reproduction process; inherent variability in the reproduction process provides for built-in trial and error species testing; the environment alone being the natural selector - no predators, per se;  an environment which was a natural source of variability in membrane structure since new chemical species were constantly being introduced through terrestrial processes as well as through comet, asteroid and meteorite impacts.

One aspect if this idea that keeps my interest is that in the presence of the correct chemical species - maybe some form of surfactant - all that would be necessary for the conditions to be favorable for the process to begin would be for the temperature to be low enough for the membranes to be stable in aqueous solution.  This idea correlates well with the observed age of the earliest cellular life on this planet - about 3.8 billion years ago.  Using an age of the earth of 4.5 billion years, this would have allowed a few hundred million years of surface cooling before the microsphere evolution began, then a few hundred million more years before anything evolved to be tough enough to survive in fossil form long enough for us to observe it.

Another intriguing side of this is that if the microsphere evolution could take place, it would provide a safe haven for an environmentally isolated series of reactions to give rise to a more advanced form of physiology, perhaps even still using the membrane as the means of inheritance.

I want to find out what you are thinking about this and about your favorite OOL ideas.  It might be fun to take one idea - this one or some other - and knock it around a while.  We could look at the membrane mechanics, the chemical specifics, molecules of heritability, physics, emergence, metabolism, physiology, kinetics, whatever perspective we want to follow.  Just a thought, but one that could be interesting.

MichiganRuss

  
Dr.GH



Posts: 1950
Joined: May 2002

(Permalink) Posted: Jan. 14 2007,01:13   

I am nearly done writing up a lit review I plan to use as a gradstudent proposal at Scripps.  Miller and Orgel are still there, and there is even something that could interest Bada.  That would be a committee.  Failing that, I'll see if I can interest Deamer. Scripps is only an hours drive from my home, so that would be much better practically speaking.  At 56 YoA, I will not be dashing off to live in student housing.  Staying in the UC system might help me avoid some of the noxious BS of grad work as that is where I did my anthropology PhD.  I want to avoid the graduate teaching requirement for example.  I taught in universites and colleges of about 25 years.  I would like to skip the language exam, BTDT.  I believe that there is still a publication alternative to a dissertation which would save time.  When I earned my degree in 1976 I was able to get out in 7 quarters.  Saves money and saves time.

If nothing else, I'll have a nice article with some apparently over looked biochem.  Most all the chemistry I have done has been using instrumental neutron activation analysis to study archaeological "stuff," clay, and pigments, the odd leaf or rock.  Well, lots of rocks.  But it was nearly 30 years since I seriously thought about organic or biochem. I had a lot of relearning.

Gramicidin was my "jumping off point" 3 years ago as well.  My basic hypothesis is that the OOL was racemic, and that chirality was a later development.  After just more than a years work on this proposal, I have finally decided to stop worrying (I could be wasting my time) and just send the #### thing off.  I have run it past two colleagues who are better chemists than I am, so I have some assurance that I have not merely lost my mind.  (Other than the question of whether it is entirely sane to return to school when I am quite happy semiretired).

I wish that we had the equivalent of the "prepublication" websites that the physicists use to such good effect.  I am really looking forward to feedback, and yes, I would like to establish priority.

Edited by Dr.GH on Jan. 14 2007,01:16

--------------
"Science is the horse that pulls the cart of philosophy."

L. Susskind, 2004 "SMOLIN VS. SUSSKIND: THE ANTHROPIC PRINCIPLE"

   
  177 replies since Dec. 15 2006,11:34 < Next Oldest | Next Newest >  

Pages: (6) < 1 2 [3] 4 5 6 >   


Track this topic Email this topic Print this topic

[ Read the Board Rules ] | [Useful Links] | [Evolving Designs]