Saturday, February 16, 2013

Show me the metabolism, marconomics, part 3

"Kauffman is chiefly concerned with reproduction as the defining feature of life. He makes only a superficial discussion of metabolism that does not consider its central thermodynamic requirements. But ultimately, metabolism is what is most important."

This reminded me of an "alien life" forum that was discussing, among other things, how we would recognise life as we don't know it. There was a consensus that at a minimum, reproduction AND metabolism would need to be observed. However, when we are talking about abiogenesis, the conundrum is more about how they have to simultaneously come about. Meaningful reproduction is impossible without metabolism to generate the work energy that reproduces something. Metabolism is pretty useless if the system that metabolises is a one off that cannot be reproduced faithfully and it's important features "locked away" for future use. The blueprint of "the system" doesn't need metabolism to exist, it needs metabolism to perform work and reproduce.

"Without petrol, the most splendidly engineered automobile will just sit there. Without a plausible metabolism, the most elegant net of autocatalytic reactions is an empty exercise in symbol manipulation."

Why can't a car be considered a living thing for the purpose of this exercise? For that matter why can't a primitive stone axe head? They perform work and can be reproduced. The system graph and energy transfers is what is important in defining what metabolism and reproduction is, not our experience of how extremely complex things that we have studied intimately perform these same system graph characteristics. Thus things like, "mass flux", "high energy flux", "vesicles", "Proto-metabolism" etc. are not particular requirements when talking about the "system" before life as we know it. The energy graph is important for when metabolism is occurring, and that the system is locked away with reproducible features when the energy/reactants source is depleted. Thus if an axe head lies in the ground undisturbed for millions of years, it would be easy to reproduce. If it was being constantly bombarded by energy flux, ie. people using it, it would just wear away until it was no longer useful. Thus, an extremely encapsulated system, with persistent, naturally reproducible features is more relevant than looking at the amount of energy flux a motorcar needs to keep going, and applying it to the needs of an axe head.

"(1) Through a long and complicated process of prebiotic development containing all the most interesting parts of the story of the origin of life.

(2) As a system created by someone or something.

I don’t intend this as an argument in favour of intelligent design [see definition 1], still less of Intelligent Design [see definition 2]. Ockham’s razor suggests we should stick with explanation (1) unless we should find some very compelling evidence for (2). At any rate, the essential requirements of the pre-biotic processes leading to life based on the chemistry we know are going to be the same as the requirements of pre-biotic processes leading to life based on different chemistry."

Ockham s razor is a lie perpetrated by scientists to make out they have gnosis when they have none. Anyway, have you considered dust cloud life? Or plasma physics life?

We don't know that life that could create chemical life is based on chemistry. We have no gnosis on the requirements of life that may have generated biochemical life through an evolutionary prebiotic process of design. All we have is human experience of design as an evolutionary process with intelligent input. The intelligence is not enough to design something complicated from scratch, and thus the sequence of precedents from transistor to computer may be accessible to historians a million years into the future. Equally, whether intelligently designed or not, we should have confidence in the possibility of precedent biological life "designs" for us to discover.

"What I am arguing is that both the ‘RNA world’ and the ‘Protein world’ are historically late phenomena, and that the critical events for the origin of life lie much deeper."

I absolutely agree with this.

"There is no reason to expect that living systems today preserve the same chemistry of the first living systems. "

I absolutely *disagree* with this. Evolution and evolutionary design processes build on what is known to work. No point changing from silicon to something else.

5 comments:

Chris Fellows said...

1. The point of these posts was to address the origin of 'life as we know it'. So they have no need to address dust cloud life or plasma physics life.

2. Broadening the definition of 'life' to include objects as well as processes is to waste a useful word. Life is a *process*, not a thing.

3. Please stop dissing Ockham's razor. Parsimony is not an ambit claim for gnosis, but a democratic and egalitarian mode of argument. You have not offered any rigorous definition of the 'marcomony' you would replace it with.

4. Sure, maybe life as we know it was designed by other life. I admit this. But I don't see any reason to therefore throw up my hands and give up thinking about possible chemical origins of life.

5. The statement you say you agree with and the statement you say you disagree with are the same statement. I am baffled if from where you stand they look like antinomies.

Marco said...

1. Life as we don't know it is constantly speculated on in science fiction. You need to address the possibility that abiogenesis as we perceive it is impossible. Your post virtually proved it to me.

2. I need a word for a non-living thing that can perform work and reproduces. These are, before life as we know it, what would count as my choices for pre-life (metabolism and reproduction)

3. We had discussed this and Marcomony is replacing Ockhams razor with a multitude of disposable razors. Lest we remove the burden of proof from a hypothesis that turns out to be impossible (though never provably impossible) I should be able to codify it to your satisfaction. I should note that I believe simplified models are a useful *engineering* tool rather than a science tool.

4. I kind of do. I vote for way less funding for wild goose chase science, and more space robots.

5. They are not the same statement. The first says that the Internet is a fairly late phenomena in the history of the electricity. The second is saying that there is no reason to believe that we use the same type electrons as we did early in the piece with electricity.

Chris Fellows said...

1. No, I don't need to address the possibility that abiogenesis as we perceive it is impossible. That is a counsel of despair, and (what is more) a Creationist stalking horse. Get thee behind me, Satan!

2. Reproduction is not important. Forget about it.

3. Okay, I will await your rigorous definition.

4. Throw up your hands if you like. And I am keen for more space robots. But there is stuff all funding for "wild goose chase science" at any rate.

5. Your metaphor only increases my bafflement. I will work on my Classical Tupi in hope that I can communicate with you more effectively in a extinct Brazilian language.

Marco said...

1. Never, never... I'd rather side with the creationists than protect dodgy hypotheses from the burden of proof.
2. Like hell. I'll go try for another baby tonight just to prove my point.
3. I will do it. I know it is very important.
4. Hmmm... I would only be guessing, but I find a lot of glamorous evolution research to be of that vein.
5.i believe I understand what you are trying to say, I just disagree with this "different but unknown" alternative chemistry. The examples I've seen are these "just so" stories. I can't accept anything other than the best chemistry won out before the best biochemistry, whether by design or accident.

Marco said...

It's funny about Marcomony. I had written a formal description and I couldn't work out where I had written it. I had put it in my knol version of my marconomics principles. Never mind it's probably new and improved now.