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Author Topic:   Life - an Unequivicol Definition
AlphaOmegakid
Member (Idle past 2866 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 1 of 374 (772316)
11-12-2015 10:32 AM


It has always amazed me that a science field like Biology is so comfortable with so many definitions which are equivocal. (Life, Evolution, Species...) But that's just the way it is. Biology is the study of life, but biologists can't agree on a definition of life. In every text book that addresses this subject, they are all quite comfortable in stating that there is no unequivocal definition of life and they usually spend a significant effort in "proving" why we can't come up with an unequivocal definition.
I suspect this indoctrination has led most Biologists to give up on the definition. But not me! I believe it is possible to create an unequivocal, simple definition of biological life or for simplicity sake an organism. I have created this definition over a period of years, and it has been tested by a number of personally know scientists.
So here it is:
Life, or a living organism is a self contained entity which uses ATP (adenosine triphosphate) for metabolism and synthesizes ATP with enzymes which are synthesized from a genetic process requiring the transfer of information from DNA to RNA.
This definition covers all known life. It is short, and unequivocal. It is minimal. And it is easily measured. It does not use abstract terms. It is, however quite different from all previous definitions that I have reviewed.
So, at a minimum, a cell must be self contained, must metabolize, and must be a "protein factory". That's a summary, and it is the minimum requirement of any known living thing. Certainly living things also can do much more that this, and this is why this definition is minimal.
So, there it is, let's see what your thoughts are?

Replies to this message:
 Message 3 by 1.61803, posted 11-12-2015 11:45 AM AlphaOmegakid has replied
 Message 5 by Blue Jay, posted 11-12-2015 12:48 PM AlphaOmegakid has replied
 Message 6 by Dr Adequate, posted 11-12-2015 1:11 PM AlphaOmegakid has replied
 Message 9 by Tanypteryx, posted 11-12-2015 3:30 PM AlphaOmegakid has not replied
 Message 10 by RAZD, posted 11-12-2015 3:54 PM AlphaOmegakid has replied
 Message 20 by dwise1, posted 11-13-2015 1:02 AM AlphaOmegakid has replied
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Message 2 of 374 (772318)
11-12-2015 11:39 AM


Thread Copied from Proposed New Topics Forum
Thread copied here from the Life - an Unequivicol Definition thread in the Proposed New Topics forum.

  
1.61803
Member (Idle past 1494 days)
Posts: 2928
From: Lone Star State USA
Joined: 02-19-2004


Message 3 of 374 (772319)
11-12-2015 11:45 AM
Reply to: Message 1 by AlphaOmegakid
11-12-2015 10:32 AM


Do you consider a virus as being alive?
Because they do not produce their own ATP.
Edited by 1.61803, : spelling edit

"You were not there for the beginning. You will not be there for the end. Your knowledge of what is going on can only be superficial and relative" William S. Burroughs

This message is a reply to:
 Message 1 by AlphaOmegakid, posted 11-12-2015 10:32 AM AlphaOmegakid has replied

Replies to this message:
 Message 4 by AlphaOmegakid, posted 11-12-2015 12:40 PM 1.61803 has replied

  
AlphaOmegakid
Member (Idle past 2866 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 4 of 374 (772321)
11-12-2015 12:40 PM
Reply to: Message 3 by 1.61803
11-12-2015 11:45 AM


Do you consider a virus as being alive?
Because they do not produce their own ATP.
I think you have answered your own question. It is not alive by my definition, and this is consistent with the consensus understanding of whether a virus is alive.

-AlphaOmegakid-
I am a child of the creator of the beginning and the end

This message is a reply to:
 Message 3 by 1.61803, posted 11-12-2015 11:45 AM 1.61803 has replied

Replies to this message:
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Blue Jay
Member (Idle past 2688 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


(1)
Message 5 of 374 (772324)
11-12-2015 12:48 PM
Reply to: Message 1 by AlphaOmegakid
11-12-2015 10:32 AM


Hi, AOkid!
It's been awhile, but it's good to see you again!
AlphaOmegakid writes:
It has always amazed me that a science field like Biology is so comfortable with so many definitions which are equivocal. (Life, Evolution, Species...) But that's just the way it is. Biology is the study of life, but biologists can't agree on a definition of life. In every text book that addresses this subject, they are all quite comfortable in stating that there is no unequivocal definition of life and they usually spend a significant effort in "proving" why we can't come up with an unequivocal definition.
One of the lines I like to use in my talks and discussions with colleagues is that modern ecologists are pretty well-trained to avoid giving clear answers to anything. This is mainly because the systems we try to study are inherently more complex than we can replicate with experiments or models, and there's a history of extended, high-profile disagreements lasting a decade or more, only to end with the realization that both sides are right under certain circumstances.
The thing that we're really starting to appreciate in modern ecology is that we don't have to develop rigid, unequivocal definitions and stances in order to make meaningful discoveries. In fact, focusing on rigid definitions more often than not distracts us from discovering the most important information.
AlphaOmegakid writes:
So here it is:
Life, or a living organism is a self contained entity which uses ATP (adenosine triphosphate) for metabolism and synthesizes ATP with enzymes which are synthesized from a genetic process requiring the transfer of information from DNA to RNA.
It's a valid enough definition, I suppose. I feel like it's needlessly specific, though. For example, it's entirely conceivable that an organism could function just as well using GTP (guanosine triphosphate) instead of ATP, and it isn't outside the realm of possibility that such an organism could be discovered on Earth. It would be better to avoid committing ourselves to a specific definition that turns out to be based on rather arbitrary decisions like this.
Also, I'm not sure I understand what we would do with this definition. Is it for the purposes of delineating academic "territories" and earmarking grant funds? Or, is it for the purposes of making a baraminological argument about lines that evolution can't cross?
Neither one of these sounds like a particularly compelling reason to me.
AlphaOmegakid writes:
This definition covers all known life.
I know you know what a tautology is.

-Blue Jay, Ph.D.*
*Yeah, it's real
Darwin loves you.

This message is a reply to:
 Message 1 by AlphaOmegakid, posted 11-12-2015 10:32 AM AlphaOmegakid has replied

Replies to this message:
 Message 14 by AlphaOmegakid, posted 11-12-2015 5:47 PM Blue Jay has replied

  
Dr Adequate
Member (Idle past 275 days)
Posts: 16113
Joined: 07-20-2006


(1)
Message 6 of 374 (772325)
11-12-2015 1:11 PM
Reply to: Message 1 by AlphaOmegakid
11-12-2015 10:32 AM


Part 1
Well, I can see some problems with your definition.
Hypothetically, suppose we met a bunch of intelligent space aliens that could discuss poetry with us and play chess with us, but had a different basis for their biology, no DNA, no ATP. According to your definition, they're not alive. They're not as alive as a bacterium. They're as alive as a rock, i.e. not alive. They don't use ATP.
But surely a definition of life should include them?
By analogy, imagine an island where a bunch of white people live, and where all the animals are black. Now, these islanders might come up with a definition of human that says: "Humans are white, anything that's black is a mere animal". But their definition is parochial, it only works for their particular island in the particular time that they're inhabiting it.
A definition of life has to include everything that we'd acknowledge as being alive if we saw it.
---
Part 2
You say that scientists equivocate over the definition of life. No they don't. A true statement would be: different scientists offer different definitions of life. None of these definitions are equivocal, they're just different. Now you've offered one more different definition. According to your idea of what makes scientist equivocal, you would just have made scientists more equivocal, if only you were a scientist.
Let's try to think of an analogy ... let's say a Japanese person has a strong opinion on whether or not gay marriage should be legal in America. He proposes that gay marriage should be legal in America if and only if the people involved are over the age of forty. Here (he says) he has a clear and unequivocal rule, whereas Americans are so equivocal. Why do they equivocate so much?
But no particular American is equivocating. Some of them say YES, some of them say NO, some say that they haven't made up their minds yet, but none of them equivocate. The Japanese guy gets to say that Americans have "equivocal" ideas because different Americans have different ideas, whereas this one Japanese guy has just one very clear idea. He's not equivocal, unlike all those equivocal Americans. And he condemns Americans for equivocating about gay marriage, whereas he has one simple unequivocal idea about gay marriage, which makes him less equivocal and more honest than all those dishonest equivocating Americans, who are collectively equivocating.
But he would actually be adding to the American "equivocation" about gay marriage if he was American. In the same way, you would be adding to the "equivocation" of scientists about the definition of life if only you were a scientist.
Well, it's easy to be "unequivocal" if you're just one person. Any group of people is going to be more equivocal. 'Cos of them being more than one person.
You see why this Japanese guy would be stupid?

This message is a reply to:
 Message 1 by AlphaOmegakid, posted 11-12-2015 10:32 AM AlphaOmegakid has replied

Replies to this message:
 Message 7 by Blue Jay, posted 11-12-2015 1:39 PM Dr Adequate has replied
 Message 137 by AlphaOmegakid, posted 11-30-2015 11:48 AM Dr Adequate has not replied

  
Blue Jay
Member (Idle past 2688 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


(1)
Message 7 of 374 (772328)
11-12-2015 1:39 PM
Reply to: Message 6 by Dr Adequate
11-12-2015 1:11 PM


Hi, Dr A.
Dr Adequate writes:
You say that scientists equivocate over the definition of life. No they don't. A true statement would be: different scientists offer different definitions of life.
I think you might be wrong about this. If we were to poll biologists with the question --- "What is the definition of 'life'?" --- I suspect that an "any of the above" or "it depends" option would be a very popular one.
Edited by Blue Jay, : Rewording

-Blue Jay, Ph.D.*
*Yeah, it's real
Darwin loves you.

This message is a reply to:
 Message 6 by Dr Adequate, posted 11-12-2015 1:11 PM Dr Adequate has replied

Replies to this message:
 Message 19 by Dr Adequate, posted 11-12-2015 10:15 PM Blue Jay has replied

  
1.61803
Member (Idle past 1494 days)
Posts: 2928
From: Lone Star State USA
Joined: 02-19-2004


Message 8 of 374 (772330)
11-12-2015 2:17 PM
Reply to: Message 4 by AlphaOmegakid
11-12-2015 12:40 PM


Hi AlphaOmegakid.
AlphaOmegakid writes:
Do you consider a virus as being alive?
I'm not
sure.
You can read the full paper here.
Just published in September 2015. I am not saying this is the end all to the question but food for thought.

"You were not there for the beginning. You will not be there for the end. Your knowledge of what is going on can only be superficial and relative" William S. Burroughs

This message is a reply to:
 Message 4 by AlphaOmegakid, posted 11-12-2015 12:40 PM AlphaOmegakid has not replied

  
Tanypteryx
Member
Posts: 4320
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 5.4


(1)
Message 9 of 374 (772334)
11-12-2015 3:30 PM
Reply to: Message 1 by AlphaOmegakid
11-12-2015 10:32 AM


AOk writes:
But that's just the way it is. Biology is the study of life, but biologists can't agree on a definition of life.
Oh sure we can.
When we trained to be biologists we learned the characteristics of life. In fact, for me that started in 7th-grade science (Mr. Jenner's class). We learned that life is incredibly complex and that not all organisms share all the characteristics.
I suspect this indoctrination has led most Biologists to give up on the definition.
It turns out that scientists use the definition that fits the context best. I have several friends who are virologists and they often treat viruses as living and refer to them as surviving or dying. At other times, they talk about viruses as complex molecules. Life is complex molecules and complex chemistry.
When biologists talk about life, if there is any confusion of their meaning, they define exactly what they mean. It depends on who we are talking to and what we are talking about.
As one alien entity on Startrek referred to humans as "Ugly bag of mostly water". It's all in the context.
This may not be very satisfying for non-scientists, but science is tentative and we are not sorry about that.

What if Eleanor Roosevelt had wings? -- Monty Python
One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie
If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

This message is a reply to:
 Message 1 by AlphaOmegakid, posted 11-12-2015 10:32 AM AlphaOmegakid has not replied

Replies to this message:
 Message 11 by Diomedes, posted 11-12-2015 4:18 PM Tanypteryx has seen this message but not replied

  
RAZD
Member (Idle past 1395 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 10 of 374 (772338)
11-12-2015 3:54 PM
Reply to: Message 1 by AlphaOmegakid
11-12-2015 10:32 AM


Welcome back/
... But not me! I believe it is possible to create an unequivocal, simple definition of biological life or for simplicity sake an organism. I have created this definition over a period of years, and it has been tested by a number of personally know scientists.
So here it is:
Life, or a living organism is a self contained entity which uses ATP (adenosine triphosphate) for metabolism and synthesizes ATP with enzymes which are synthesized from a genetic process requiring the transfer of information from DNA to RNA.
Mine is simpler: anything capable of evolution. (cue definition of evolution ^(1)... ).
This not only includes viruses but self-replicating molecules. The essential difference in my opinion between life and non-life is that one evolves (life) and one doesn't (non-life).
Enjoy
(1) The process of evolution involves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities for growth, development, survival and reproductive success in changing or different habitats.

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This message is a reply to:
 Message 1 by AlphaOmegakid, posted 11-12-2015 10:32 AM AlphaOmegakid has replied

Replies to this message:
 Message 13 by AlphaOmegakid, posted 11-12-2015 5:40 PM RAZD has replied
 Message 21 by dwise1, posted 11-13-2015 1:06 AM RAZD has replied
 Message 26 by Blue Jay, posted 11-13-2015 12:03 PM RAZD has replied

  
Diomedes
Member
Posts: 995
From: Central Florida, USA
Joined: 09-13-2013


(1)
Message 11 of 374 (772346)
11-12-2015 4:18 PM
Reply to: Message 9 by Tanypteryx
11-12-2015 3:30 PM


I have several friends who are virologists and they often treat viruses as living and refer to them as surviving or dying.
And that brings up an interesting conundrum: isn't 'death' the inevitable end of life? And if so, being that viruses can effectively 'die', doesn't that in and of itself give credence to classifying them as 'life'?
I'm no biologist so I frankly have no opinion one way or the other. But it seems to be, as others have alluded to, that pigeon-holing life into a singular definition may be constraining.
Does anyone remember that Michael Crichton book 'The Andromeda Strain'? It was turned into a great movie in 1971. The reason I bring it up, is that it was around a team of scientists there were trying to deal with an outbreak of an alien organism that had infected and killed the people of a small town. When they analyzed the organism, they realized it had a crystalline structure and was able to convert energy without the need for amino acids and nucleic enzymes. Yet it was still 'alive'.
I realize that is still science fiction, but ultimately, classifying life to fit a definition that is very specific to the Earth (and not to all organisms on Earth) may be a little too narrow in view.

This message is a reply to:
 Message 9 by Tanypteryx, posted 11-12-2015 3:30 PM Tanypteryx has seen this message but not replied

  
1.61803
Member (Idle past 1494 days)
Posts: 2928
From: Lone Star State USA
Joined: 02-19-2004


Message 12 of 374 (772357)
11-12-2015 5:13 PM



"You were not there for the beginning. You will not be there for the end. Your knowledge of what is going on can only be superficial and relative" William S. Burroughs

  
AlphaOmegakid
Member (Idle past 2866 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 13 of 374 (772359)
11-12-2015 5:40 PM
Reply to: Message 10 by RAZD
11-12-2015 3:54 PM


Thanks for the welcome back
RAZD writes:
Mine is simpler: anything capable of evolution. (cue definition of evolution ^(1)... ).
This not only includes viruses but self-replicating molecules. The essential difference in my opinion between life and non-life is that one evolves (life) and one doesn't (non-life).
Enjoy
(1) The process of evolution involves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities for growth, development, survival and reproductive success in changing or different habitats.
Oh I quite enjoyed!
Look at your definition. You of all people should know better than this! Populations evolve, not individual organisms. So by you definition, only populations are alive, because only populations are capable of evolving. Individual entities cannot be alive, because individuals do not evolve. I guess you just died. I don't think you will get too far with that one in the science community. But then again maybe you will!
However, with my definition, individual entities can be alive, viruses are not living, and all individual molecules including self replicating ones are not living. This is also in compliance with cell theory which your definition violates if you think evolution includes things like viruses and self-replicating molecules. Unless you can show evidence why cell theory is wrong then you have no logical warrant to include these entities under the definition of evolution. It just doesn't follow from your own definition of evolution.

This message is a reply to:
 Message 10 by RAZD, posted 11-12-2015 3:54 PM RAZD has replied

Replies to this message:
 Message 15 by Tanypteryx, posted 11-12-2015 6:02 PM AlphaOmegakid has replied
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AlphaOmegakid
Member (Idle past 2866 days)
Posts: 564
From: The city of God
Joined: 06-25-2008


Message 14 of 374 (772360)
11-12-2015 5:47 PM
Reply to: Message 5 by Blue Jay
11-12-2015 12:48 PM


BlueJay writes:
It's been awhile, but it's good to see you again!
Ditto’s! Does that make me a ditto head?
BlueJay writes:
One of the lines I like to use in my talks and discussions with colleagues is that modern ecologists are pretty well-trained to avoid giving clear answers to anything.
Yes, I understand, that’s your training. That’s what I meant by indoctrination.
BlueJay writes:
This is mainly because the systems we try to study are inherently more complex than we can replicate with experiments or models
Yet some can model climate change with authority! Hmmmmm?
BlueJay writes:
, and there's a history of extended, high-profile disagreements lasting a decade or more, only to end with the realization that both sides are right under certain circumstances.
Why would there be disagreements if there were no definitive discussions about the experiments or models? It seems as though you are contradicting yourself. And how could there be two sides to a discussion if those sides were not defined unequivocally. And how could both sides be right if the circumstances were not identified and defined? It seems, you have made my point. After the decades of discussion and argument from both definitive sides, then both sides have some things right. This is the falsification process within science. It happens through clear unequivocal definitions. Sure definitions are wrong sometimes, partially right sometimes, and not wrong sometimes. It is the not wrong ones that science strives for.
BlueJay writes:
It's a valid enough definition, I suppose. I feel like it's needlessly specific, though.
Needlessly specific?? I guess that’s more training?
BlueJay writes:
For example, it's entirely conceivable that an organism could function just as well using GTP (guanosine triphosphate) instead of ATP, and it isn't outside the realm of possibility that such an organism could be discovered on Earth. It would be better to avoid committing ourselves to a specific definition that turns out to be based on rather arbitrary decisions like this.
Well if you follow the logic on the definition you might see why I chose ATP rather than GTP. ATP as you know is the main unit of energy currency within the cell. And all cells use ATP for all metabolic processes. GTP is also used for metabolic processes, but only a couple. So it is as you say conceivable that a living cell could have ATP but not GTP, but it is not conceivable that a cell could be considered alive if it had no ATP. So it is a minimalist definition. I do not agree that a living cell could just as well use GTP rather than ATP. It’s the other way around. You would have to somehow show that GTP can be used instead of ATP in all the metabolic processes within a cell. And according to Cell Theory the smallest living thing is a cell.
Regarding the tautology , yes I know what one is, but I don’t see how you are applying it. Shed some light in this darkness!

This message is a reply to:
 Message 5 by Blue Jay, posted 11-12-2015 12:48 PM Blue Jay has replied

Replies to this message:
 Message 18 by Blue Jay, posted 11-12-2015 9:21 PM AlphaOmegakid has replied

  
Tanypteryx
Member
Posts: 4320
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 5.4


(1)
Message 15 of 374 (772364)
11-12-2015 6:02 PM
Reply to: Message 13 by AlphaOmegakid
11-12-2015 5:40 PM


AlphaOmegakid writes:
RAZD writes:
Mine is simpler: anything capable of evolution. (cue definition of evolution ^(1)... ).
This not only includes viruses but self-replicating molecules. The essential difference in my opinion between life and non-life is that one evolves (life) and one doesn't (non-life).
Enjoy
(1) The process of evolution involves changes in the composition of hereditary traits, and changes to the frequency of their distributions within breeding populations from generation to generation, in response to ecological challenges and opportunities for growth, development, survival and reproductive success in changing or different habitats.
Look at your definition. You of all people should know better than this! Populations evolve, not individual organisms. So by you definition, only populations are alive, because only populations are capable of evolving.
Wow, that one went right over your head, didn't it?
Individual entities cannot be alive, because individuals do not evolve.
because only populations are capable of evolving.
This is really only the case for sexually reproducing species. Asexually reproducing species like many bacteria and other single celled organisms can and do evolve when mutations occur in individual organisms.
And while populations evolve, the mutation part of evolution occurs in the sex cells of individuals.

What if Eleanor Roosevelt had wings? -- Monty Python
One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie
If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

This message is a reply to:
 Message 13 by AlphaOmegakid, posted 11-12-2015 5:40 PM AlphaOmegakid has replied

Replies to this message:
 Message 16 by AlphaOmegakid, posted 11-12-2015 6:27 PM Tanypteryx has replied

  
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