What are the Odds of Life evolving by chance alone?

[CharonY]

I have to agree with Ophiolite. Nonewithstanding any intentions may may have had, life in itself is a tricky and somewhat arbitrary concept. That does not in any way invalidate concepts of evolution or any approaches one may have developed towards understanding abiogenesis (quite the opposite I may argue).

As I has been pointed out by Ophiolite, me and many others the definition of live is a concept that we created for practical purposes but does not necessarily reflect reality on all complexity levels. For example, with a very simplified view you could argue that cells perform homeostatic actions, and to some extent they do. For many approaches it is useful to assume a certain type of steady-state, too.

But obviously things change almost on a constant basis if looked closely enough (just think in terms of cell cycles etc.). One should get used to the fact that certain definitions are matters of convenience to be able to frame specific questions.

 

 

Edit:

Cross-posted with Arete, but he provided a beautiful example why the definitions are in flux. To give a counter-view, coming from a more systems-oriented view that does not specialize on evolutionary processesI would consider viruses more to be mobile genetic elements with no distinct metabolic activities. Both views are valid for the respective questions being investigated.

Edited November 28, 2013 by CharonY

[Alan McDougall]

I am supporting a couple of statements made by Alan that I stumbled upon when revisiting the thread, because those statements are valid and wholly consistent with current thinking on abiogenesis. You appear to be attacking his statements because you believe him to be a creationist, not because of the inherent value of the statements. I oppose such an approach when I see it, for it is unscieintific.

 

Can one answer after the "death of a single cell", what is "absence" and exactly how does the "dead cell differ from its living state", lets leave out for a while the death of a complex organism, like a human body, which is more complex and progressive.

 

Please this is not to put forward a creationist point of view as some suppose in the thread. However, there is something missing from the dead cell" that was intrinsic or endogenuos when it was it biologically alive. Is this some sort of electric charge or magnetic martix? I am talking here about animal life, plant life differs a little.

[CharonY]

Generally one would consider a cell dead once integrity has been compromised to an extent that it cannot resume regular cellular functions. There is usually not a single element but a strong indicator is membrane integrity. If that fails, energy generation stops and there is no real way to recover from there.

 

But there are usually many factors that may lead to this, including complex apoptosis programs that result in a controlled cell death. Again, there is no singular magic spark that determines whether a cell is alive or not, but many elements that fail, sometimes in a coordinated manner.

[Alan McDougall]

Generally one would consider a cell dead once integrity has been compromised to an extent that it cannot resume regular cellular functions. There is usually not a single element but a strong indicator is membrane integrity. If that fails, energy generation stops and there is no real way to recover from there.

 

But there are usually many factors that may lead to this, including complex apoptosis programs that result in a controlled cell death. Again, there is no singular magic spark that determines whether a cell is alive or not, but many elements that fail, sometimes in a coordinated manner.

 

Thus my earlier statement that the exact differences between living entities and dead ones, are vague must be correct, but was dismissed as nonsense by a member

 

What I am trying to understand, during medievil times it was supposed by some early biologists, that some sort of "Life Force" animated living things. (I am not talking about the soul!). Thus is there one sort of "Bilogical Spark" that equates to the hypothetical life force and animates living bilogical entities?

Edited November 28, 2013 by Alan McDougall

[CharonY]

It is necessarily so, as biological entities are highly complex and so are their properties. A simple description for complex properties are necessarily imprecise. The terms life and death are superficially precise, but if looked deeper into that it is clear that they are not (again, because it is used as a description for biological, complex entities).

This does actually go further as the way we describe things so that we can understand them is obviously highly context dependent (see Arete's example). I used the term "fail" to describe cell death, but of course in the context of programmed cell death it is not a failure, but precisely the way things work so that an organism can live (whereas the cell dies). In truth, biological processes are are just highly physical processes, and we give them specific terms in order to better describe them within specific contexts.

 

I should stress: the terminology is only vague if you try to apply them in an universal context. Within certain research areas the terms are usually used in a very precise manner. Apoptosis for example is a highly structured form of cell death. Other or similar parameters can be used depending on whether you are looking at cells from a cytotoxicity, developmental or cell physiological viewpoint.

Edited November 28, 2013 by CharonY

[Arete]

Thus my earlier statement that the exact differences between living entities and dead ones, are vague must be correct, but was dismissed as nonsense by a member

 

A) The only person who's actually used the word "nonsense" at all in this thread is you.

 

B) What we've been explaining to you is that this statement you made:

 

 

 

When somebody is studying the phenomenon of viruses ,he can see that when viruses are not coming in contact with a host organism, they are a sum of chemical compounds that not fulfill the criteria to be considered as life.

 

Is inaccurate. Biological entities don't fall neatly into categories. A virus isn't "dead" outside of a cell and become "alive" inside of a cell. There's shades of grey between "alive" and "not-alive" which viruses fall into. There isn't a right and a wrong in the argument you're trying to make - as charonY and I have pointed out it's all dependent on context. "Alive" and "not alive" are in some respects, simply categories of convenience.

[Alan McDougall]

 

A) The only person who's actually used the word "nonsense" at all in this thread is you. Implied!

 

B) What we've been explaining to you is that this statement you made:

 

 

 

 

Is inaccurate. Biological entities don't fall neatly into categories. A virus isn't "dead" outside of a cell and become "alive" inside of a cell. There's shades of grey between "alive" and "not-alive" which viruses fall into. There isn't a right and a wrong in the argument you're trying to make - as charonY and I have pointed out it's all dependent on context. "Alive" and "not alive" are in some respects, simply categories of convenience.

 

Shades of grey between "alive and 'not - alive, is that not vague just like I stated earlier?

 

In what state, exactly then is a strand of virus RNA outside a host?

 

Viruses can’t accomplish many of the major of functions of life on their own outside of the host cell it has been debated for many years whether viruses are indeed “alive.”

Edited November 30, 2013 by Alan McDougall

[Ringer]

Shades of grey between "alive and 'not - alive, is that not vague just like I stated earlier?

It's not that it's vague, it's just artificial and arbitrary. Some areas would define death as the end of metabolic activity, but under some circumstances that doesn't work so another definition is used. Biology isn't always clear cut because evolution doesn't care about how easily we define things.

 

In what state, exactly then is a strand of virus RNA outside a host?

It depends on who you ask, what type of virus it is, etc. One of the reasons you're having so much negative blow back from your questions is because you seem to be expecting a simplistic answer to a very complex question.

 

Viruses can’t accomplish many of the major of functions of life on their own outside of the host cell it has been debated for many years whether viruses are indeed “alive.”

It all depends on the usefulness of whatever working definition of 'alive' you are using at the time. Sometimes they can be thought of as alive, sometimes they can be thought of as non-living entities. Alive or not alive isn't a strict category.

[Alan McDougall]

Viruses are the most plentiful biological things known, maybe having more total mass than any other organism, because they exist somewhat in the grey areas between living entities and non-living entities, might they hold the clue how ancient life first emerged from lifeless matter, taking Abiogenesis out of the realms of speculation.

[Ophiolite]

Viruses are the most plentiful biological things known, maybe having more total mass than any other organism, because they exist somewhat in the grey areas between living entities and non-living entities, might they hold the clue how ancient life first emerged from lifeless matter, taking Abiogenesis out of the realms of speculation.

Well, they might do that, but I tend to doubt it. My understanding, possibly outdated, is that many/most/all viruses arose by subtraction from more complex "things", rather than being a stepping stone to more complex "things".

 

Please note that the majority of members here are agreeing with you that the definition of life is vague. This is because, as CharonY and others have noted, biology is complex; organisms are comple; simple words - inappropriately applied - can confuse rather than clarify.

 

Earlier you asked if there might be some force that was responsible for the difference between liviing and non-living entities. This is a valid question, but one that was answered over a century ago. Vitalism, is a now discredited concept - discredited since there is no significant evidence in favour of it. Do you continue to suspect that it may exist? That there is some elan vital at work? If so, why do you think this and what would it take to dissaude you?

[Arete]

Shades of grey between "alive and 'not - alive, is that not vague just like I stated earlier?

 

You seem to be fixated on whether or not you are "right" as opposed to whether or not your argument is sensible, which unfortunately it doesn't really appear to be.

 

Definitions of life can be as specific or vague as one wishes.The difficultly arises not because the various definitions of life are vague, but because biological systems are complex and thus tend to obfuscate arbitrary categorization.

 

An analogy would be colors. We can define our colors very specifically, e.g. "true" blue light has a wavelength of 475nm and "true" green light has a wavelength of 510nm. What's light with a wavelength of 492.5nm? It's exactly halfway between green and blue - so calling it blue would be equally correct (or incorrect) as calling it green. Our definitions aren't vague - on the contrary, they are very precise. Light itself isn't vague, as calling an object vague is nonsensical. The inconsistency arises through the existence of intermediate states between our precise definitions.

 

 

In what state, exactly then is a strand of virus RNA outside a host?

 

It depends. A virus, per se is usually made up of nucleic acids and proteins, rather than randomly distributed strands of RNA - so a strand of RNA of any kind floating around an environment would generally not be a virus (or any other organism) at all. Then there are RNA viruses, ssDNA viruses, dsDNA viruses, those that contain their own polymerase, those that utilize a host's, etc etc etc. So dependent on the location of that strand of RNA that has viral origin (e.g. inside a capsid, incorporated into a host genome, randomly floating in the environment, etc) it may be a virus, a transposable element, a plasmid, an insertion, an intron, environmental DNA, mRNA, or any other number of components of biological systems.

 

As a result, your question without context is not answerable.

Edited December 2, 2013 by Arete

[Alan McDougall]

Well, they might do that, but I tend to doubt it. My understanding, possibly outdated, is that many/most/all viruses arose by subtraction from more complex "things", rather than being a stepping stone to more complex "things".

 

Please note that the majority of members here are agreeing with you that the definition of life is vague. This is because, as CharonY and others have noted, biology is complex; organisms are comple; simple words - inappropriately applied - can confuse rather than clarify.

 

Earlier you asked if there might be some force that was responsible for the difference between liviing and non-living entities. This is a valid question, but one that was answered over a century ago. Vitalism, is a now discredited concept - discredited since there is no significant evidence in favour of it. Do you continue to suspect that it may exist? That there is some elan vital at work? If so, why do you think this and what would it take to dissaude you?

No! I am not a believer in Vitalism, but there must be a scientific biological answer to the question?

 

What caused, some selective "previously nonliving" matter in the primordial past, to become "animated and alive"? Take the brain, it uses very tiny electric impulses to pass messages/parts of messages, between neurons (Of course many other factors as well)

[Ophiolite]

What caused, some selective "previously nonliving" matter in the primordial past, to become "animated and alive"?

Physics and chemistry. What do you find unsatisfactory about that answer? (I am pretty sure you do find it unsatisfactory, else we would not be having this discussion.)

 

It is, at times, frustrating that we do not yet know the details of exactly how this occured. But it is also inspiring and exciting that through diligent application of the scientific method we shall eventually know. You give the impression that our current state of ignorance of the detail is a failing of science. Perhaps you would clarify your thinking on these points, since some of the antagonism you are experiencing may arise from these impressions (that may be faulty).

[Dekan]

Surely the idea of "Vitalism" can't be entirely dismissed?

 

There does seem to be a big difference between live neurons and dead transistors

 

Alan points out in post #212, that neurons use very tiny electrical impulses. Which is what transistors do in a integrated circuit, or computer chip. Yet - we can't use such "chips" to create an artificial brain like the HAL 9000 computer in "2001: A Space Odyssey".

 

HAL's artificial brain was supposedly so good, that he not only conducted spoken conversations, and recognised sketches of faces - "That's Dr Hunter isn't it?" - but - piece de resistance - actually read Dave and Frank's lip movements when they were talking about disconnecting him!

 

Is that credible? It seems difficult to get a computer to recognise a straight edge, never mind reading lips.

 

Couldn't his difficulty come about because computers aren't made of living matter such as flesh?

Edited December 2, 2013 by Dekan

[Ringer]

Brains do not use electrical impulses, that implies the movement of electrons. Neurons use electrochemical gradients.

 

Sorry, but it's a little terminology pet peeve.

[Greg H.]

Surely the idea of "Vitalism" can't be entirely dismissed?

 

There does seem to be a big difference between live neurons and dead transistors

 

Alan points out in post #212, that neurons use very tiny electrical impulses. Which is what transistors do in a integrated circuit, or computer chip. Yet - we can't use such "chips" to create an artificial brain like the HAL 9000 computer in "2001: A Space Odyssey".

 

HAL's artificial brain was supposedly so good, that he not only conducted spoken conversations, and recognised sketches of faces - "That's Dr Hunter isn't it?" - but - piece de resistance - actually read Dave and Frank's lip movements when they were talking about disconnecting him!

 

Is that credible? It seems difficult to get a computer to recognise a straight edge, never mind reading lips.

 

Couldn't his difficulty come about because computers aren't made of living matter such as flesh?

The limitations of computers to do things, such as read lips, are not limitations in what they are made of (living versus dead), but limitations in the software algorithms that they operate and the spoeed of the hardware running them.

 

I am a perfectly living, breathing, human being, and I can't read lips at all. Ten years ago you had to program a voice recognition system with samples of your voice just so it could understand you. My iPhone could follow my voice commands out of the box, no cumbersome phrases required. As the algorithms get more complex, and processing power improves, I have no doubt you'll see lip reading computers - if nothing else, the value to espionage agencies would be enormous, and probably quite sufficient to drive development.

 

Edit: 2009 called - they want their computer back.

http://news.cnet.com/8301-13639_3-10227163-42.html

Edited December 2, 2013 by Greg H.

[Alan McDougall]

Brains do not use electrical impulses, that implies the movement of electrons. Neurons use electrochemical gradients.

 

Sorry, but it's a little terminology pet peeve.

Of course anyone reading my response, (were I used the brain as an example of an electric driven organism) with even the minutest understanding of biology, would know that I meant electrochemical.

Physics and chemistry. What do you find unsatisfactory about that answer? (I am pretty sure you do find it unsatisfactory, else we would not be having this discussion.)

 

It is, at times, frustrating that we do not yet know the details of exactly how this occured. But it is also inspiring and exciting that through diligent application of the scientific method we shall eventually know. You give the impression that our current state of ignorance of the detail is a failing of science. Perhaps you would clarify your thinking on these points, since some of the antagonism you are experiencing may arise from these impressions (that may be faulty).

 

Of course I do not believe that if some questions "are presently" beyond the scope of science to answer, that it is some sort of failure due to scientific effort. Questions have been asked by the greatest minds over all off human history, some even apparently simplistic and childlike, such as Albert Einstein imagining riding on a beam of light, a thought that might have led to General Relativity

[Ringer]

Of course anyone reading my response, (were I used the brain as an example of an electric driven organism) with even the minutest understanding of biology, would know that I meant electrochemical.

 

 

Well, since using the term electric tends to give false analogies such as the transistor one above I would hope one could see were saying electricity would become a problem. It's a useful analogy sometimes, but I think it brings more misunderstanding that understanding. Hence why I said it was just a pet peeve.

[Alan McDougall]

 

Well, since using the term electric tends to give false analogies such as the transistor one above I would hope one could see were saying electricity would become a problem. It's a useful analogy sometimes, but I think it brings more misunderstanding that understanding. Hence why I said it was just a pet peeve.

 

Explanation accepted

[beanieb]

Physics and chemistry. What do you find unsatisfactory about that answer? (I am pretty sure you do find it unsatisfactory, else we would not be having this discussion.)

 

It is, at times, frustrating that we do not yet know the details of exactly how this occured. But it is also inspiring and exciting that through diligent application of the scientific method we shall eventually know. You give the impression that our current state of ignorance of the detail is a failing of science. Perhaps you would clarify your thinking on these points, since some of the antagonism you are experiencing may arise from these impressions (that may be faulty).

As of now.. we must agree neither sides (the group that says "life" can be derived from non living chemicals just by itself, vs the group that supports it requires more than just the chemical makeup) can yet prove each other to be absolutely true or false...

 

As such, we should realise each of our standpoint is still motivated by "faith system", and not derived entirely from "neutral objective " science.

 

Yet the 1st group tends to argue in the name of science as if it is the truth already (when how abiogenesis works is still not well understood, but like a blackbox. To say it has the answer and believing in it before the proof.. is more faith than fact ya?)

Edited December 23, 2013 by beanieb

[CharonY]

The first group, as you put it, refers to the knowledge of chemistry and physics, while acknowledging that there is a knowledge gap somewhere. The second just assumes that there is something there but has not inkling as to what nature it may be.

 

The first assumption and any hypotheses derived from there can be subjected to scientific scrutiny. The latter provides no explanatory power whatsoever. However, this has been repeated ad nauseam.

[StringJunky]

beanieb, on 23 Dec 2013 - 06:09 AM, said:beanieb, on 23 Dec 2013 - 06:09 AM, said:

Yet the 1st group tends to argue in the name of science as if it is the truth already (when how abiogenesis works is still not well understood, but like a blackbox. To say it has the answer and believing in it before the proof.. is more faith than fact ya?)

Logic says go with the system that has evidence.

 

"Since things are much more ancient than letters, it is no marvel if, in our day, no records exist of these seas having covered so many countries. . . But sufficient for us is the testimony of things created in the salt waters, and found again in high mountains far from the seas." - Leonardo Da Vinci

 

http://www.ucmp.berkeley.edu/history/vinci.html

 

With an open mind, travel down both paths side by side and see which one gets you the furthest.

 

Edited December 23, 2013 by StringJunky

[Dekan]

What is "Life"?

[Moontanman]

What is "Life"?

 

 

Life is what happens while you are making other plans...

 

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

 

Life is a characteristic that distinguishes objects that have signaling and self-sustaining processes from those that do not,^[1][2]

 

As of now.. we must agree neither sides (the group that says "life" can be derived from non living chemicals just by itself, vs the group that supports it requires more than just the chemical makeup) can yet prove each other to be absolutely true or false...

Science doesn't prove things as absolutely true or false...

 

As such, we should realise each of our standpoint is still motivated by "faith system", and not derived entirely from "neutral objective " science.

No, while not as overwhelming as the evidence for evolution the evidence for abiogenesis is quite robust and in no way a faith based system...

 

Yet the 1st group tends to argue in the name of science as if it is the truth already (when how abiogenesis works is still not well understood, but like a blackbox. To say it has the answer and believing in it before the proof.. is more faith than fact ya?)

Again science doesn't deal in proof but evidence and the evidence for abiogenesis is quite strong but more importantly there is no evidence that life is anything other than chemistry

[Alan McDougall]

a·bi·o·gen·e·sis (b--jn-ss)

 

 

The supposed development of living organisms from nonliving matter. Also called autogenesis, spontaneous generation.

The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

abiogenesis [ˌeɪbaɪəʊˈdʒɛnɪsɪs]n

1. (Life Sciences & Allied Applications / Biology) Also called autogenesis the hypothetical process by which living organisms first arose on earth from nonliving matter

2. (Life Sciences & Allied Applications / Biology) another name for spontaneous generation Compare biogenesis

 

I thought a definition might be of interest to those not fully informed in the life sciences