Is Life Inevitable?

Posted 15 November 2006 by Ian Musgrave

The origin of life is one of the most fascinating and controversial of scientific topics. The event occurred so long ago, and left so little clues, that we have struggled in our understanding of it. The basic building blocks of life turn up in meteors, cosmic dust and the gas clouds surrounding stars, as well as being manufactured on Earth in almost every conceivable environment. But how we get from these simple building blocks to metabolism, genes and organisms is not entirely clear, despite several promising lines of attack. How probable is the origin of life? Creationists and Intelligent Design advocates alike claim that it is highly improbable. Most scientists think we are still at too immature a stage of knowledge to even speculate. However, a recent paper (free PDF here) by Harold Morowitz and Eric Smith in the Sante Fe Institute working papers series , suggests that life might be inevitable on thermodynamic grounds.

... the continuous generation of sources of free energy by abiotic processes may have forced life into existence as a means to alleviate the buildup of free energy stresses.

There is a good over view at Nature News (free online), and you might like to drop in on the Nature NewsBlog on this subject. Myself, I'm not convinced. While they make a good case for a simple autotrophic core of reactions forming the start of life chemistry, there are a range of details missing in their treatment of the thermodynamic aspects. However, this is a promising start from which more formal treatments can be derived. Anyway, read the paper and the Nature commentary, and see what you think. Check out some of the other working papers on the origin of life as well. Update: Astronomy Now has a very interesting article on new experimental approaches to prebiotic chemistry.

43 Comments

Miguelito · 15 November 2006

Does anybody else find the Morowitz and Smith *.pdf file unreadable?

Kevin · 15 November 2006

That's not "Astronomy Now", just "Astronomy" (magazine).

Dizzy · 15 November 2006

Fascinating...I remember reading a (highly speculative) article a while back hypothesizing that any sufficiently large system containing limited types of "building blocks" would almost inevitably create some sort of auto-catalytic system, i.e. some permutation of A produces B, B produces C, C produces A. It didn't tie that concept to biological life (as we know it) nearly as much as this article attempts, though.

Gary Hurd · 15 November 2006

Another recent article that is chemistry focused is;

"{alpha}-Hydroxy and {alpha}-Amino Acids Under Possible Hadean, Volcanic Origin-of-Life Conditions" Claudia Huber and GÃ¼nter WÃ¤chtershÃ¤user. Science 27 October 2006 314: 630-632

Gary Hurd · 15 November 2006

Miguelito, the PDF worked fine for me.

Fans of the RNA world will enjoy reading the perspective "Versatility of Self-Cleaving Ribozymes" by Michael D. Been, Science 22 September 2006: Vol. 313. no. 5794, pp. 1745 - 1747 DOI: 10.1126/science.1133259

Flint · 15 November 2006

Carl Sagan, among others, have noted that we find evidence of life as early in the history of our planet as remaining evidence allows us to look, and all indications are that it arose almost as soon as conditions allowed. Eukaryotes, now, took another 3 billion years to appear. Although Sagan admits it's hard to extrapolate for a single datum, the suggestion is that life is probably unavoidable, but any particular given evolutionary path after that event qualifies as nearly miraculous.

wright · 15 November 2006

Absolutely fascinating. Granted this hypothesis has a long way to go, but what a trip it will be, even if it doesn't pan out!

To me, this is another example of how science can invoke a sense of wonder and appreciation of nature. "Nature" in this case meaning the abiotic processes that continue to dominate the universe.

David B. Benson · 15 November 2006

This seems a good thread to make another plug for the book "Into the Cool", which offers a similar perspective in a highly readable fashion...

Peter Henderson · 15 November 2006

Did anyone in the UK catch Horizon Last night:

http://www.bbc.co.uk/sn/tvradio/programmes/horizon/broadband/tx/aliens/

I tuned in just as it was ending, but it dealt with this very subject. I attended a lecture that Chandra Wickramasinghe gave at the Irish Astronomical Association a couple of years ago and he certainly had some interesting ideas. I'm sure I read somewhere that he testified at one of the creation trials in the US in the early 1980's.

The idea that life could have originated in space is not mere speculation or a fudge as creationists claim. (they often refer back to the results of Pasteur's experiment...that life can only come from life). During one of the Apollo missions a camera was left behind on the Moon's surface. When a later mission returned they found that a number of bacteria had survived. This means that microbial life can exist in very harsh environments. It may in fact be relatively common throughout the solar system if not throughout the Universe. It may also be possible that it (microbial life) could have traveled to the Earth from other planetary bodies,like Mars for example.

Parse · 16 November 2006

Though I can't say anything about life being inevitable, I'm pretty sure that death is.

Popper's ghost · 16 November 2006

... the continuous generation of sources of free energy by abiotic processes may have forced life into existence as a means to alleviate the buildup of free energy stresses.

Don't these guys understand that teleology is only a valid form of explanation for intentional systems?

We must be careful, however, in describing the more stable state to which earth collapsed. It is probably wrong to regard biomass as a thermodynamic "state" of terrestrial matter.

Not so much wrong as silly, like taking the distinguishing feature of brains to be their temperatures. This is a lot like Roger Penrose trying to explain consciousness in terms of quantum collapse in microtubules; it's the worst sort of naive reductionism, an attempt to explain a highly structured system at a level that doesn't take the structure into account.

Popper's ghost · 16 November 2006

they often refer back to the results of Pasteur's experiment...that life can only come from life).

Of course, Pasteur's experiment couldn't have shown any such thing, because no experiment can prove a universal. All Pasteur showed was that microbes failed to appear when blocked from external sources but not otherwise, strongly suggesting that the source was external, as opposed to spontaneous generation. This is so much more limited a result than the creationists' characterization of it, that the probability is infinitesimal that any of them have any familiarity with it.

Popper's ghost · 16 November 2006

The biochemical processes of living organisms are highly organized. Scientists have long puzzled over how such systems can come spontaneously into being, when the second law of thermodynamics says that the universe as a whole generates increasing disorder.

Really? I'm not aware of any scientists puzzling over such a thing, as they are generally aware of the existence of the sun, and of course more generally ...

The answer, broadly speaking, is that local clumps of order come at the expense of increasing the disorder around them.

So if Mr. Ball is aware of the well-known answer to this "puzzle", why does he think that "scientists" don't? Also, he writes

Russell has used similar ideas to argue that "life would emerge using the same pathways on any sunny, wet rocky planet". The most likely place for it to occur, he believes, is at miniature undersea volcanoes called hydrothermal vents, where the ingredients and conditions are just right for energy-harnessing chemical machinery to develop.

But the latter statement is not similar to what Morowitz and Smith are arguing, which is that the conditions were globally right, in fact they saturated the environment, forcing the occurrence of proto-metabolic processes. They may well be right, but there's a huge gap between that and -- poof! -- "Eventually these processes will have become encapsulated into cells".

Torbjörn Larsson · 16 November 2006

"I'm pretty sure that death is."

In their non-individualistic perspective, life got started and haven't died yet.

As Ian and PG I have some problems with their thermodynamics as it is now, meanwhile this particular idea was endearing. Either life started once and has been robust or lucky enough to survive extinction events, or it got restarted several times because it was 'inevitable'. Enough for a (here crappy) bayesian argument.

Popper's ghost · 16 November 2006

I suspect that the first comment at Nature Newsblog has it right:

Morowitz and Smith's proposal that life may have been forced into existence to alleviate a continuous build-up of free energy requires that the most primitive replicators at the origin of life can actually release a free energy stress. This, however, may not be the case. Owing to their low metabolic demands and inefficient replication it seems unlikely that primitive replicators can produce populations that absorb even a marginal fraction of the free energy in open thermodynamic systems. This seems instead to require ecosystems composed of more evolved organisms with higher energetic demands, suggesting that the abilities of biotic systems to absorb free energy is a consequences of the evolved state of the system, more than it is a consequence of it's origin. Nevertheless, the complex organisms on Earth may be inevitable. Given the origin of self-replicating molecules in open thermodynamic systems with a continuous inflow of energy, recent theoretical studies suggest that major biological transitions evolve deterministically in the long run from a natural selection that is imposed by the energetic state of individual self-replicators and the density dependent competitive interactions between self-replicators in natural populations [Witting, 2002 (Theor. Pop. Biol: 61:171) & 2003 (J. theor. Biol. 225:389)].

Flint · 16 November 2006

Don't these guys understand that teleology is only a valid form of explanation for intentional systems?

I'm sure they do, but I don't see the teleology myself. Think of a steady stream of sand into a pile. Every now and then, small avalanches occur because stress buildups on asymmetrical sand grains become unsupportable. These are "forced into existence as a means to alleviate the buildup of stresses" in perhaps an analogous way, but no teleology is involved. All we have is a system reaching a more stable equilibrium under changing circumstances. They're suggesting that the advent of life is the path of least resistance, and is sure to occur eventually because of this.

Popper's ghost · 16 November 2006

"I'm pretty sure that death is." In their non-individualistic perspective, life got started and haven't died yet.

But surely you don't doubt that it eventually will. Parse got it right, regardless of the level.

Katarina · 16 November 2006

Dawkins argues in The God Delusion that the origin of life is many times more improbable than its evolution, but that it only had to happen once, and it happened to happen on this planet, in this galaxy, in this universe. The fact that we are here to talk about it is proof enough of that, and only that.

I have a question though, how can we calculate such a probability?

Indeed, the fact that evolution is an undirected process makes theistic evolution undefensible for anything but a faraway deity that set things into motion at the very beginning. And that view isn't consistant with a God who answers prayers. In fact, this argument is what finally convinced me to abandon TE.

Popper's ghost · 16 November 2006

Thus, they say, despite several major extinctions throughout geological time, each of which almost obliterated every living thing, life itself was never in danger of disappearing --- because an Earth with life is always more stable than one without. The researchers call this process a "collapse to life", which in their view is as inevitable as the appearance of snowflakes in cold, moist air.

So why isn't there life on every planet? As far as I can see, they don't identify anything specific about Earth that makes life inevitable here but not elsewhere. I call BS.

Popper's ghost · 16 November 2006

I'm sure they do, but I don't see the teleology myself.

"as a means to" is teleological, plain and simple.

These are "forced into existence as a means to alleviate the buildup of stresses"

No, they occur as a consequence of the buildup of stresses. If you jump off a tall building, your bones don't break as a means to relieve the force of impact.

They're suggesting that the advent of life is the path of least resistance, and is sure to occur eventually because of this.

They can suggest all they want, but it's a hindsight-driven ad hoc just-so story that explains nothing and isn't supported by any specific facts.

Katarina · 16 November 2006

In The God Delusion, I'm sure most of you are aware, the concession (of sorts) is made that the origin of life is much more improbable than its evolution, yet it only had to happen once. The fact that we are here to talk about it is proof that it happened to happen on this planet, in one of possibly many universes. But that is all it says. How do we calculate this probability, though?

Don't these guys understand that teleology is only a valid form of explanation for intentional systems?
— Popper's Ghost

Popper's ghost · 16 November 2006

BTW, to head off any silly debate, I'll refer to the dictionary:

an agency, instrument, or method used to attain an end

Any further denial that "means" is teleological is dishonest.

Popper's ghost · 16 November 2006

BTW2: If one accepts that "means" is teleological (as one must) but still claims that the Morowitz and Smith statement is acceptable, then one accepts teleological explanations of
non-intentional systems, the very thing Flint says Morowitz and Smith surely know better than to do.

k.e. · 16 November 2006

Katrina wrote:

How do we calculate this probability, though?Popper's Ghost wrote: Don't these guys understand that teleology is only a valid form of explanation for intentional systems?

This is the very argument that devastatingly challenged my notion of theistic evolution, forcing me to abandon it. Ken Miller defends it by imagining a deistic kind of god that got things started long ago and let them unfold, but this makes no sense either Miller's defense/apologetics seems to me to be some sort of Spinozan view, in other words all of nature IS GOD, at least that survives explosive logic. The rest he leaves to his own conscious. However obvious questions remain to be begged, the creationists being too rational for their own good, realize that and draw a line by making Myth real thus no inconvenient questions to consider . If Le Grande Frommage lit a fuse for the big bang he? would have blown herself to smithereens ....so when someone comes out of desert after 40 days who was he talking to? ...himself obviously.

GuyeFaux · 16 November 2006

Miller's defense/apologetics seems to me to be some sort of Spinozan view, in other words all of nature IS GOD, at least that survives explosive logic.

I don't this Miller is Spinozan at all. But that discussion has been had already, at length: basically, Miller is definitely Christian, whereas with Spinoza it's hard to tell and I would guess not.

Popper's ghost · 16 November 2006

Miller's defense/apologetics seems to me to be some sort of Spinozan view, in other words all of nature IS GOD

Uh, Miller's a Roman Catholic.

k.e. · 16 November 2006

Miller is definitely Christian, whereas with Spinoza it's hard to tell and I would guess not

They don't make Jews like Jesus or Spinoza any more. Since I'm not a Christian but a Martian anthropologist, all religions look the same to me. I was speaking not in a parochial sense but in a comparative sense. Ultimately no matter how seriously people take the ideas of gods, thats all they are ...ideas. And when ideas of their own start making rocks move on their own, then I might take them more seriously. Without being flippant ideas can be very dangerous in the wrong hands that is the real problem.

k.e. · 16 November 2006

Uh, Miller's a Roman Catholic.

Good for him. And I'm a DGaFist so what? Yes, yes I'm aware of that ...the borrowed Greek Hermetic/Hindu trinity Myth and all that, there probably is something like that in one of the Jewish Mythologies and it's Levantine precursors as well. The whole question of god/gods/creators/destroyers/whatevers if religion/Mythic world view is removed as a factor falls to the individuals heresy i.e. personal choice... at least supposing one has that freedom where they live. As far as abiogenesis is concerned nothing made by man in his own image could possibly have had any effect on it, end of story.

k.e. · 16 November 2006

Uh, Miller's a Roman Catholic.

Good for him, I'm a DGaF***ist. Yes, yes I'm aware he is a follower of a Trinity Myth which is also in the older Greek Hermetic Mythology, the even older Egyptian Mythologies and the Hindus have one three. I'm guessing but the Levantine traditions pre Hebrew probably have some as well. One's selection of heresy,which they all are, is usually not free from religious power players. The whole point of gods/antigods/creators/destroyers/whatevers and etceteras in fact anything men have made in their own image could not possibly have any effect on abiogenesis except in how the concept is interpreted and politicized

Flint · 16 November 2006

"as a means to" is teleological, plain and simple.

Simple maybe. Plain? Well, let's say you have imbued this with a semantic content I wouldn't read into it myself.

No, they occur as a consequence of the buildup of stresses.

And the same thing again. I extract no different hidden meanings between this formulation and the "as a means of" formulation. Now, "with the intention of" I'd read differently.

They can suggest all they want, but it's a hindsight-driven ad hoc just-so story that explains nothing and isn't supported by any specific facts.

This matches my understanding completely. I think I understand what they're trying to say, but I also think this is empty guesswork.

Any further denial that "means" is teleological is dishonest.

A bit brittle and harsh here. I submit that it's legitimate to say that Newton's apple falls "by means of" gravity, without suggesting that gravity is applying purpose or intent. However, I know that surrounded by the appropriate context not present here, a means can be regarded as "a method used to achieve an end", as teological as you can get. Also, teleological phrasing is a common linguistic shortcut which doesn't by any stretch imply the presumption of intent. It's not uncommon to say something along the lines of "water wants to run downhill" without anyone being tricked into thinking water has wants the way people do. In other words, I don't read any conceptual mistake being made by Morowitz and Smith, although a deliberately perverse reading of their word selection can project such a mistake onto them. And yes, I think it is perverse to presume that Morowitz and Smith "believe" that inanimate systems have intents and motivations. This perversity only distracts from what they're trying to say. I don't think they have supported their thesis, but lack of support isn't the same as conceptual error.

Peter Henderson · 16 November 2006

So why isn't there life on every planet? As far as I can see, they don't identify anything specific about Earth that makes life inevitable here but not elsewhere. I call BS.

The fact that microbial life can exist in very harsh environments (the Lunar surface for example, is a near vacuum, suffers extreme temperature variations, and endures copious amounts of harmful radiation) shows that this type of life could be more common than we think. Also, don't forget that the atmosphere in the early Earth would also have been fairly toxic and definitely not anything like today. Another point. All stars have a habitable zone. Both Venus and Mars fall within the sun's habitable zone,by the way. Stars that are more massive than the sun would not last long enough for life to start. We are limited to looking at Earth like planets that orbit stars that are either the same size or less massive than the sun.It's reckoned that the most common type of star in the Universe is actually a red dwarf. These will also have habitable zones but these will be much closer to that type of star than for our own sun. http://www.solstation.com/habitable.htm It's a pity we don't have the technology to visit Mars or Europa.

k.e. · 16 November 2006

It's a pity we don't have the technology to visit Mars or Europa.

Why do you think I'm here? Us Martians after destoying our atmosphere and making the planet uninhabitable sent explorers to find intelligent life on other planets and warn them to look after theirs, because there are no real other alternatives to living on the home planet. We're still looking for that intelligent world leader who can understand that, we had a word to Rupert Murdoch but I think he's planning on cryocloning and going to Alpha Centauri.

stevaroni · 16 November 2006

they often refer back to the results of Pasteur's experiment...that life can only come from life

It's as pet peeve of mine, but I'm always annoyed at ID citing something Pasteur or Darwin said as if it were somehow unalterable Biblical writ. The store of scientific knowledge has moved on a little in 150 years. While I'm endlessly grateful for Ampere, Faraday and Maxwell for laying the foundations for my particular profession, I don't go looking to them for definitive information on how to build modern micprocessors. Likewise, Darwin was perfectly correct to speculate about whether he had the right answer back in the day, he was breaking new ground with very limited data. But a century and a half later, whether he had doubts or not is immaterial. We're not working with what he knew or did not know, we're working with what we know. There's a difference. I assume this annoying tendency comes from the dependence that religious leaders place on the inerrant word of the prophets, where you're supposed to come down the mountain with perfect holy writ, but in science it's just annoying. OK, I'm done ranting for a while. Back to the program.

stevaroni · 16 November 2006

So why isn't there life on every planet?

How do you know that there isn't? As far as our known samples go, you have Earth (a hit), the moon (no life yet, but the infamous mariner camera seems to show that life can survive there) and Mars (which has shown at least some - albeit controversial - promise). Given the pathetically small sample size, we're still batting at least .333 That can get you a place on the Cardinals roster, and they just took the series.

Michael Suttkus, II · 16 November 2006

Infamous Mariner camera? Have you guys been holding out on me?

stevaroni · 16 November 2006

Infamous Mariner camera? Have you guys been holding out on me?

My bad, that should have been "Surveyor camera". One of the Apollo missions ( A14, I believe ) landed within a few hundred yards of one of the old Surveyor moon probes ( soft-landers from the mid-60's ). It was a stunning display of precision navigation, ostensibly to recover some samples of what would happen to electronics exposed to the harsh lunar environment for years. The astronauts cut off, and returned with, the Surveyor's lunar camera. Upon dissasembly it was found to be harboring a small colony of dormant bacteria in some insulation, and these were subsequently revived. The bacteria were terrestrial, of course, and there was some dispute as to whether they were on the moon for the whole time, or got into the camera on the ride home. But this was in days before bacteria were discovered in polar ice, oil wells and volcanic vents, so it gave us an early glimpse into the pretty fascinating possibility that common bacteria were a whole lot more durable than previously suspected.

Henry J · 16 November 2006

Re "Upon dissasembly it was found to be harboring a small colony of dormant bacteria in some insulation, and these were subsequently revived."

Oh, so the bacteria weren't active or growing while there, just sort of barely hanging on. So it's not evidence that something could thrive in that environment.

Henry

stevaroni · 16 November 2006

Oh, so the bacteria weren't active or growing while there, just sort of barely hanging on. So it's not evidence that something could thrive in that environment.

Thrive, no, at least not these bacteria. But the fact that they could even survive that kind of abuse speaks volumes about how far life can stretch. If they can do that cold out of the box, imagine if they'd had a few hundred thousand generations to acclimate; perhaps they'd even evolve new survival strategies - like maybe eating nylon. Nah - that's crazy talk.

Henry J · 16 November 2006

If they can do that cold out of the box, imagine if they'd had a few hundred thousand generations to acclimate; perhaps they'd even evolve new survival strategies - like maybe eating nylon. Nah - that's crazy talk.

It certainly is - where are they gonna find stockings on the moon? Stockings only live where there's feet, and ain't none of those on the moon lately. ;)

David B. Benson · 16 November 2006

Popper's ghost --- I take it you don't care for the Morowitz & Smith paper. What do you think of "Into The Cool", which is similar, but avoids (much) discussion of abiogenisis?

Rolf Aalberg · 17 November 2006

So why isn't there life on every planet? As far as I can see, they don't identify anything specific about Earth that makes life inevitable here but not elsewhere. I call BS.

I may be wrong, but doesn't this quote from their paper indicate that the authors discriminate - even if they do not specifically identify specifics, between 'every planet' - and Earth-like planets?

--- would imply that life had to emerge on the earth, that at least the early steps would occur in the same way on any similar planet, and that we should be able to predict many of these steps from first principles of chemistry and physics together with an accurate understanding of geochemical conditions on the early earth.

Torbjörn Larsson · 17 November 2006

PG:
"Parse got it right, regardless of the level."

Agreed.

brightmoon · 17 November 2006

i also got a weird alphabet soup when i clicked on the morowitz paper pdf ...i went over to the santa fe site to see if i could find it manulally .....and just to make sure, clicked on the link again ...this 2nd time it worked huh????????