9 ms·

Forgive me if I'm dense, but I read the article twice and don't see how this is anything more than a well known fact getting some science journalism coverage to

by ABCLAW 9y ago

Forgive me if I'm dense, but I read the article twice and don't see how this is anything more than a well known fact getting some science journalism coverage to seem important. Is the big news here that someone in physics has applied a crude model to the very well understood theory of abiogenesis? We've literally ran this experiment in vitro. With real chemicals. I'm not sure how the entropic basis of the theory provides any insight beyond 'capacity for work can generate things that have capacity for work', which we knew. The big question isn't, and wasn't, whether a system with primordial chemicals could generate self-replicating reactions and structures - you could figure that out by looking in a mirror. It's what those primordial cycles actually were. Edit: Looks like the dude's former supervisor working in chem isn't full of shit like the rest of the article is: Shakhnovich said, but “Jeremy’s work represents potentially interesting exercises in non-equilibrium statistical mechanics of simple abstract systems.” Any claims that it has to do with biology or the origins of life, he added, are “pure and shameless speculations.” TLDR - might be interesting in niche modeling field, but has nothing to do with origins of life.

api 9y ago
There's no well understood theory of abiogenesis. For something to be a theory it must be supported by repeatable experiment and/or repeatable observation. The difference between hypothesis and theory is very important. There are many good hypotheses on abiogenesis but until someone demonstrates rudimentary repeatable abiogenesis in the lab without "hand-holding" interventions then it's not a theory. (Or alternately finds a way to observe strong evidence for abiogenesis and how it occurred in the fossil record in a reproducible way that is specific enough to rule out other explanations for the same data.)
- dragonwriter 9y ago
  Your general description is correct, but your specific application is not; because you've implicitly in the latter limited empirical confirmation such as to juatify the label theort to direct observation or indirect observation that admits no other explanation. Neither is required, and the latter would move it beyond theory to irrefutable fact, as an observation “that is specific enough to rule out other explanations”, obviously, rules out all other explanations.)
- ABCLAW 9y ago
  That's not correct. There's no scientific theory of abiogenesis, because we haven't elucidated the entire pathway and developed falsifiable methods of determining which of the various models is correct, but there certainly is a theory of abiogenesis. In fact, the theory is so well developed that there isn't really a competing scientific explanation to explain how life ultimately arose other than through abiogenesis. The area of research has been fairly fertile, to the point that many of the findings in that field have spun off into their own areas of research, from their original pursuit of the origins of life.
  - aaronblohowiak 9y ago
    >to the point that many of the findings in that field have spun off into their own areas of research, from their original pursuit of the origins of life. That sounds fascinating. Can you give some examples?
  - oldandtired 9y ago
    If there is no scientific theory of abiogenesis then there can be no theory so well developed that there is no competing scientific explanation. If it isn't science in the first place, it can't be science in the second place. Abiogenesis and evolution as complementary ideas and its competition of intelligent design are philosophical standpoints attempting to portray themselves as science. They are metaphysical. A simple example of one of the current evolutionary ideas is that there is much "junk" dna within each lifeform. If this is so, then with the current technology, we should be able to edit this "junk" dna out of the chromosomal dna structure and still be able to have fully viable lifeforms that breed true and are fully compatible for the pre-edited lifeforms. if there is 80% "junk", we should be able to edit this 80% out with no ill side-effects. If it turns out that we can't edit this "junk" out without causing non-viability or ill side-effects that that dna was not "junk" in the first place. Over all the hundreds of millions of species existing on this planet, we should be able to find all sorts of species that are in transition forms (having partially functional organs or forms) today. You can make all sorts of claims about what has happened in the past, especially when you cannot actually test those living organisms in the lab.
    - 9y ago
EGreg 9y ago
There is no THE theory of abiogenesis. The main question for me is abiogenesis. How did the first self-replicating things evolve? It seems that the kolmogorov complexity of the simplest quines in most languages is relatively high. One would imagine that, in terms of chemistry, the kolmogorov complexity of something that can self-replicate and also evolve with mutations which do not prevent the replication from taking place over generations - ie resilience - is too high to have arisen by mere chance.
- Houshalter 9y ago
  Be wary of anthropic bias. If this universe didn't happen to support life, then we wouldn't exist here to observe it. Perhaps there are other universes with different laws of physics, and we would exist in one of them instead. And even in our own universe, there are many trillions of planets. Yet we only know of one that has evolved life. The fact that we observe life here tells us nothing about how probable it is. In fact as far as we can tell, life is extremely rare. We've only found one instance of it forming on it's own. And it can only exist in a very tiny space between the earths crust and the upper atmosphere (and only in very small quantities in most of that space.) We haven't found self replicating systems on other planets or deep within the earth. So any theory that posits "life is an inevitable outcome of thermodynamics" is almost certainly wrong. It's a theory that can't be falsified, and has no predictive power. A more interesting theory would be one that can explain why our specific planet and our specific laws of physics support life. Why do exist here instead of somewhere else?
  - EGreg 9y ago
    Yep it seems to be rare, thus falsifying the theory that England is developing. And by the way, can't multiverse thinking be invoked pretty much anytime to explain anything? "Oh we have fine tuning that is a knife's edge 1 part in 10 to the 127th" "Yeah well maybe we have even more universes." That's not real science. That's actually digging your heels in and saying "there is nothing beyond what we already found and understand". How will you go about testing this?
    - 9y ago
laretluval 9y ago
> The big question isn't, and wasn't, whether a system with primordial chemicals could generate self-replicating reactions and structures - you could figure that out by looking in a mirror. OK, we knew that, but what are the precise conditions under which it is more or less likely to happen? Understanding that requires a mathematical theory of exactly how self-replicating patterns form under the laws of thermodynamics, which is what this line of work is aiming to provide.
- ABCLAW 9y ago
  It's a cute paper telling biochemists things they already knew. The biochemical sciences aren't discovering entropy for the first time. The premise this work adopts doesn't add to our understanding of complex chemical systems. Believe me, there are plenty of computational chemists in the world.
joobus 9y ago
> a system with primordial chemicals could generate self-replicating reactions and structures - you could figure that out by looking in a mirror Only if you require no evidence, and no verifiable, independently confirmed experiments to back up your claim. What you said is basically the scientist's version of intelligent design at this point.
- xenadu02 9y ago
  There have been plenty of experiments showing that the building blocks of life will spontaneously self-assemble under the right conditions. We have now confirmed that comets and other bodies in space contain complex molecules such as hydrocarbons. There are also plenty of experiments demonstrating that certain structures self-assemble and even "replicate" (for some definition of replicate) under the right conditions, purely as a function of their molecular structure. There is no conclusive proof... but certainly everything we've discovered to date supports abiogenesis of life given the right conditions and a few 100 million years for many trillions of attempts. It is likely that the first "life" wasn't life as we would define it, more like a prion: a self-replicating molecule built out of amino acids dumped on Earth from meteorite and comet impacts. The first true "life" was probably exceedingly simple and lived off chemical reactions around hydrothermal vents.
  - oldandtired 9y ago
    No conclusive proof? No proof at all. Go and listen to James Tour and his video on the problems of just getting the right pre-life chemical synthesis to occur. He is a organic chemist (one of the top in the world) and he talks about each of the incompatible processes between each step. I would be more inclined to take his word for it than a biologist (of any stripe). Abiogenesis seems to be the least likely scenario in the formation of life (as in close to 0 as to make no difference) irrespective of the amount of time that is allocated.
    - gnaritas 9y ago
      > Abiogenesis seems to be the least likely scenario in the formation of life Yet we know it happened, because life exists, and it didn't spring from magic so it must have sprung from non-life. Random chance is a hell of a search algorithm, abiogenesis is simply the inevitable outcome randomly trying every possible combination over hundreds of millions of years. There are no more likely scenarios.

by ABCLAW 9y ago

api 9y ago

There's no well understood theory of abiogenesis. For something to be a theory it must be supported by repeatable experiment and/or repeatable observation. The difference between hypothesis and theory is very important. There are many good hypotheses on abiogenesis but until someone demonstrates rudimentary repeatable abiogenesis in the lab without "hand-holding" interventions then it's not a theory. (Or alternately finds a way to observe strong evidence for abiogenesis and how it occurred in the fossil record in a reproducible way that is specific enough to rule out other explanations for the same data.)

dragonwriter 9y ago
Your general description is correct, but your specific application is not; because you've implicitly in the latter limited empirical confirmation such as to juatify the label theort to direct observation or indirect observation that admits no other explanation. Neither is required, and the latter would move it beyond theory to irrefutable fact, as an observation “that is specific enough to rule out other explanations”, obviously, rules out all other explanations.)
ABCLAW 9y ago
That's not correct. There's no scientific theory of abiogenesis, because we haven't elucidated the entire pathway and developed falsifiable methods of determining which of the various models is correct, but there certainly is a theory of abiogenesis. In fact, the theory is so well developed that there isn't really a competing scientific explanation to explain how life ultimately arose other than through abiogenesis. The area of research has been fairly fertile, to the point that many of the findings in that field have spun off into their own areas of research, from their original pursuit of the origins of life.
- aaronblohowiak 9y ago
  >to the point that many of the findings in that field have spun off into their own areas of research, from their original pursuit of the origins of life. That sounds fascinating. Can you give some examples?
- oldandtired 9y ago
  If there is no scientific theory of abiogenesis then there can be no theory so well developed that there is no competing scientific explanation. If it isn't science in the first place, it can't be science in the second place. Abiogenesis and evolution as complementary ideas and its competition of intelligent design are philosophical standpoints attempting to portray themselves as science. They are metaphysical. A simple example of one of the current evolutionary ideas is that there is much "junk" dna within each lifeform. If this is so, then with the current technology, we should be able to edit this "junk" dna out of the chromosomal dna structure and still be able to have fully viable lifeforms that breed true and are fully compatible for the pre-edited lifeforms. if there is 80% "junk", we should be able to edit this 80% out with no ill side-effects. If it turns out that we can't edit this "junk" out without causing non-viability or ill side-effects that that dna was not "junk" in the first place. Over all the hundreds of millions of species existing on this planet, we should be able to find all sorts of species that are in transition forms (having partially functional organs or forms) today. You can make all sorts of claims about what has happened in the past, especially when you cannot actually test those living organisms in the lab.
  - 9y ago

EGreg 9y ago

There is no THE theory of abiogenesis. The main question for me is abiogenesis. How did the first self-replicating things evolve? It seems that the kolmogorov complexity of the simplest quines in most languages is relatively high. One would imagine that, in terms of chemistry, the kolmogorov complexity of something that can self-replicate and also evolve with mutations which do not prevent the replication from taking place over generations - ie resilience - is too high to have arisen by mere chance.

Houshalter 9y ago
Be wary of anthropic bias. If this universe didn't happen to support life, then we wouldn't exist here to observe it. Perhaps there are other universes with different laws of physics, and we would exist in one of them instead. And even in our own universe, there are many trillions of planets. Yet we only know of one that has evolved life. The fact that we observe life here tells us nothing about how probable it is. In fact as far as we can tell, life is extremely rare. We've only found one instance of it forming on it's own. And it can only exist in a very tiny space between the earths crust and the upper atmosphere (and only in very small quantities in most of that space.) We haven't found self replicating systems on other planets or deep within the earth. So any theory that posits "life is an inevitable outcome of thermodynamics" is almost certainly wrong. It's a theory that can't be falsified, and has no predictive power. A more interesting theory would be one that can explain why our specific planet and our specific laws of physics support life. Why do exist here instead of somewhere else?
- EGreg 9y ago
  Yep it seems to be rare, thus falsifying the theory that England is developing. And by the way, can't multiverse thinking be invoked pretty much anytime to explain anything? "Oh we have fine tuning that is a knife's edge 1 part in 10 to the 127th" "Yeah well maybe we have even more universes." That's not real science. That's actually digging your heels in and saying "there is nothing beyond what we already found and understand". How will you go about testing this?
  - 9y ago

laretluval 9y ago

> The big question isn't, and wasn't, whether a system with primordial chemicals could generate self-replicating reactions and structures - you could figure that out by looking in a mirror. OK, we knew that, but what are the precise conditions under which it is more or less likely to happen? Understanding that requires a mathematical theory of exactly how self-replicating patterns form under the laws of thermodynamics, which is what this line of work is aiming to provide.

ABCLAW 9y ago
It's a cute paper telling biochemists things they already knew. The biochemical sciences aren't discovering entropy for the first time. The premise this work adopts doesn't add to our understanding of complex chemical systems. Believe me, there are plenty of computational chemists in the world.

joobus 9y ago

> a system with primordial chemicals could generate self-replicating reactions and structures - you could figure that out by looking in a mirror Only if you require no evidence, and no verifiable, independently confirmed experiments to back up your claim. What you said is basically the scientist's version of intelligent design at this point.

xenadu02 9y ago
There have been plenty of experiments showing that the building blocks of life will spontaneously self-assemble under the right conditions. We have now confirmed that comets and other bodies in space contain complex molecules such as hydrocarbons. There are also plenty of experiments demonstrating that certain structures self-assemble and even "replicate" (for some definition of replicate) under the right conditions, purely as a function of their molecular structure. There is no conclusive proof... but certainly everything we've discovered to date supports abiogenesis of life given the right conditions and a few 100 million years for many trillions of attempts. It is likely that the first "life" wasn't life as we would define it, more like a prion: a self-replicating molecule built out of amino acids dumped on Earth from meteorite and comet impacts. The first true "life" was probably exceedingly simple and lived off chemical reactions around hydrothermal vents.
- oldandtired 9y ago
  No conclusive proof? No proof at all. Go and listen to James Tour and his video on the problems of just getting the right pre-life chemical synthesis to occur. He is a organic chemist (one of the top in the world) and he talks about each of the incompatible processes between each step. I would be more inclined to take his word for it than a biologist (of any stripe). Abiogenesis seems to be the least likely scenario in the formation of life (as in close to 0 as to make no difference) irrespective of the amount of time that is allocated.
  - gnaritas 9y ago
    > Abiogenesis seems to be the least likely scenario in the formation of life Yet we know it happened, because life exists, and it didn't spring from magic so it must have sprung from non-life. Random chance is a hell of a search algorithm, abiogenesis is simply the inevitable outcome randomly trying every possible combination over hundreds of millions of years. There are no more likely scenarios.