The origins of abiotic species

January 4, 2016

How can life originate from a lifeless chemical soup? This question has puzzled scientists since Darwin's 'Origin of species'. University of Groningen chemistry professor Sijbren Otto studies 'chemical evolution' to see if self-organization and autocatalysis will provide the answer. His research group previously developed self-replicating molecules—molecules that can make copies of themselves—and have now observed diversification in replicator mutants. They found that if you start with one ancestral set of replicator mutants, a second set will branch off spontaneously. This means that ecological diversity as encountered in biology may well have its roots at the molecular level. The results were published on Jan. 4, 2016, in Nature Chemistry.

Life must have started at some point, but how remains a mystery. Charles Darwin himself speculated in a letter to Joseph Hooker in 1871: 'But if (and oh what a big if) we could conceive in some warm little pond with all sorts of ammonia and phosphoric salts,—light, heat, electricity & c. present, that a protein compound was chemically formed, ready to undergo still more complex changes, at the present day such matter wd be instantly devoured, or absorbed, which would not have been the case before living creatures were formed.'

It is impossible to know how life on Earth really started, but that doesn't stop scientists from trying to find out how it could have started. This is not just a matter of curiosity. The processes involved include autocatalysis (where molecules promote the formation of copies of themselves) and (where molecules spontaneously organize themselves into higher-order structures) which are important concepts in such fields as materials science.

Replicators

Otto has been working on for several years now. 'It started with a chance discovery', he explains. 'We found some small peptides that could arrange themselves into rings, which could then form stacks.' Once a stack began to form, it would continue to grow and would then multiply by breaking into two smaller stacks. These would both grow and break again, and so on. The stacks also stimulated the formation of the rings from which they are composed. The stacks and rings are called 'replicators', as they are able to make copies of themselves.

Jan Sadownik, a postdoc in the Otto group, discovered that if you offer the replicators two different types (A and B) of building blocks ('food') they will make copies of themselves. He observed the emergence of a set of replicator mutants that specialized in food A, but also incorporated some B. The rings mainly comprised the A building blocks, with just a few B's.

Some days later Sadownik saw a second set of mutants emerge that specialized in food B, but also tolerated some A. This second set proved to be a descendant of the first set, which meant there was an ancestral relationship between the sets. This is very similar to how new species form from existing ones during biological evolution, except that this process of species formation does not involve full-fledged biological organisms, but occurs instead at the molecular level.

Molecular speciation

Looking at the molecular 'speciation' process in more detail allowed the researchers to identify specific mutants within the first set of replicators that were responsible for the generation of the second set. They had therefore established the mechanism by which replicator 'species' form with unprecedented detail. The spontaneous diversification of replicating molecules into distinct sets may well have been the first step in a long process that has led to the stunning that we see all around us today.

This shows how new 'species' can emerge through chemical evolution. Otto explains, 'Of course, the term speciation should only be used when referring to sexually reproducing organisms, but our work shows much the same patterns.' The exciting part, says Otto, is that 'we start with no replicators, but see first one type emerge and then after a while, another. That is certainly most significant!'

The next step is to introduce death. This can be done by feeding the system a constant flow of , while draining the contents of the reaction vessel. Replicators can only survive in this system when their growth rate exceeds the removal rate. 'We could then seed such a system with one set of replicator mutants, and then change the environment, for example by adding another solvent. This would change the fitness of the various replicator mutants and shift the population of mutants towards those that are best at replicating in the new environment.' The result would be a form of natural selection that Darwin would recognize. 'We're not the only ones to be really excited about these experiments - the evolutionary biologist I've consulted is too.'

Explore further: How Did Evolution Begin?

More information: Jan W. Sadownik, Elio Mattia, Piotr Nowak and Sijbren Otto: Diversification of self-replicating molecules. Nature Chemistry, Advanced Online Publication Jan. 4, 2016, DOI: 10.1038/nchem.2419

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26 comments

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Torbjorn_Larsson_OM
5 / 5 (11) Jan 04, 2016
"It is impossible to know how life on Earth really started".

Ouch. It is impossible to claim that it is impossible to know how life on Earth really started, since we can eventually know in any number of ways.

More interesting is to note that it is hard since we have been at it so long, and first recently started to make testable theories.
antialias_physorg
4.6 / 5 (10) Jan 04, 2016
It is impossible to claim that it is impossible to know how life on Earth really started, since we can eventually know in any number of ways.

They are referring to fact that, given the outlined mechanisms in the paper, there are likely a vast set of possibilities how life got started. And without actually going back and observing which way it was (or whether it was another way altogether) we'll never know for certain.
What we're left is is picking the most probable one (from the known set).

Time machines, alas, are probably not in the cards in this universe.
Torbjorn_Larsson_OM
4.9 / 5 (7) Jan 05, 2016
@aapo: I actually made that observation in a longer (too long) version of the comment.

Picking the most probable tree is what we do elsewhere in biology, but no one has the tedious notion of claiming that it isn't knowing or that the standard procedure is 'impossible' or not robust. (It can't resolve every detail usually, but it pinpoints a small set of alternatives.) Yet it is somehow all right to make absurd claims about life emergence, and to do them as a matter of course.

Just a nit of mine of course, but I prefer to see my science on an empirical basis instead of embroidered with made up (and unnecessary) elements.
viko_mx
1.4 / 5 (10) Jan 05, 2016
The matter without the breath of life from the living God will never become alive even if it is perfectly organized in 3d structure thanks to the efforts of intelligent beings. This is hard fact for materialists with their limited worldview.
In this universe the spirit of God moves the matter and gives direction to the processes in nature. Without spirit and will the motion is impossible.
animah
5 / 5 (11) Jan 05, 2016
matter (...) will never become alive

Strange assertion given everything that is alive is made entirely of matter.

You might counter that the soul is not made of matter but I'm pretty sure plants and low-order lifeforms don't have souls in your creed.

That means their existence is entirely mechanistic. Or do you believe viruses and bacteria have immanent souls?
viko_mx
1.5 / 5 (8) Jan 05, 2016
In fact living organisms are not just matter, but also the spirit and the breath of life. Our DNA also is not just matter. It has connection with the divine matrix.
Whydening Gyre
5 / 5 (9) Jan 05, 2016
In fact living organisms are not just matter, but also the spirit and the breath of life. Our DNA also is not just matter. It has connection with the divine matrix.

I find it truly remarkable when people pronounce "divine wisdom" by repudiating our capacity to gain it.
And, BTW - It's not a DIVINE matrix, it's just a matrix. Definable, if you have the time and resources to gather, store and collate all that data (which we're working on, I'm sure).
animah
5 / 5 (11) Jan 05, 2016
Our DNA also is not just matter


Viko, what about this::

http://spectrum.i...oduction

"DNA Manufacturing Enters the Age of Mass Production"

"Constructing a strand of DNA isn't complicated; in fact it's a routine procedure performed in labs all over the world. (...) So she and her cofounders invented a machine that automates the construction process."

Today the most complex life that has been fabricated from scratch are yeast and viruses, but the tech is advancing rapidly.

So your position that our DNA also is not just matter seems untenable.
jsdarkdestruction
5 / 5 (10) Jan 06, 2016
The matter without the breath of life from the living God will never become alive even if it is perfectly organized in 3d structure thanks to the efforts of intelligent beings.

Conjecture based on religous beliefs. Prove it scientifically.just because we haven't made life yet does not mean we never can.
This is hard fact for materialists with their limited worldview.

You are the one with a limited worldview who can't accept facts. What is a materialist exactly in your view ?
In this universe the spirit of God moves the matter and gives direction to the processes in nature. Without spirit and will the motion is impossible.

Another conjecture biased by your religous beliefs. What scientific evidence do you have?
Whydening Gyre
5 / 5 (7) Jan 06, 2016
I wonder if the dinosaurs thought about a god...
Were they sayin' "Oh My G...!" when the big meteor hit?
meerling
5 / 5 (8) Jan 06, 2016
Why do religion trolls keep trolling in science comments & forums?
jsdarkdestruction
5 / 5 (9) Jan 06, 2016
Why do religion trolls keep trolling in science comments & forums?

They like to believe that they have everything all figured out and that their particular God of choice is special and different from all the other made up gods mans dreamt up. Anyone who doesn't believe the same thing are inferior they feel. Ego, pride, and vanity, to sum it up. The same sins they love to accuse others of.
Torbjorn_Larsson_OM
5 / 5 (8) Jan 06, 2016
More ouch, trolling magic on a science site.

Same as when biology showed 2011 that the religious idea of a single human breeder pair, already unlikely due to population genetics, is impossible due to the genome populations we and Neanderthal's share. All human population bottlenecks have been much larger than the religious magicians claims.

Same here, it is worse than that "the soul is not made of matter". The LHC showed 2013 explicitly that any such magical idea simply can't exist, if you don't accept the implicit rejections by the existence of thermodynamics et cetera that shows our world is entirely non-magical.

[ctd]
Torbjorn_Larsson_OM
5 / 5 (7) Jan 06, 2016
It is quite simple, so I am surprised no one has published a paper on it.

LHC finalized the standard particle model enough so we can estimate non-chemistry effects on molecules. Famously the vacuum of quantum physics is closed under interaction, i.e. a particle field will feel all its possible interactions. That puts an energy bound on non-chemistry effects on biochemistry.

Now sum up the number of synapses in the human brain. To put a lower bound, allow that religious magic has somehow a map of them (creationists would claim every human is blueprinted long ago). To take a simplest possible copy of the firing pattern mechanism into a putative magic backup 'soul' that has an existence separate from the actual living, breathing, thinking organism, you need to decide on the momentaneous state of each synapse as a yes/no bit.

[ctd]
Torbjorn_Larsson_OM
5 / 5 (6) Jan 06, 2016
Then you don't have any fancy coding where you can average over long times to get below the thermal energy threshold, it is momentaneous remember? Add it all up and compare: you still need 1000 times as much energy* injected into the entire brain volume than LHC allows on such an average.

Either religious magicians will claim they are pinheads. [But please count us others out!] The religious gap-of-the-religious-brains-dancing-on-pins.

Or such magicians have to reject the 'soul'/'spirit' garbage if they want to adhere to science, to what we see and what we know.

************

*Since it is a lower bound we don't consider the Nyquist signal criteria.

Else there would be a factor 2-10 times as much signal energy shunted off to a putative magical 'soul' interaction with particles in practice; the quick estimate is 10 times at best.
Torbjorn_Larsson_OM
5 / 5 (6) Jan 06, 2016
I just realized the basic irony of creationism. They claim that nature is planned (blueprinted) long ago, yet when it comes to the brain they believe in free willies so that I don't have to describe the last used constraint for them. Speak of seeing nature upside down or frontside back!

But for us living in the real world the workings of the brain is a complex, often unknown outcome of (mostly) deterministic biochemistry. This is why we agree with magicians that their putative magic 'soul' has to snoop on it. (The break with the energy bound becomes even higher if they claim their magic somehow control chemical reactions.) No time machine predetermination is allowed.
Torbjorn_Larsson_OM
5 / 5 (7) Jan 06, 2016
[I forgot to add to the last comment that of course the LHC rejection is a more complex - but new, fresh and IMO interesting - way to make the same rejection that medicine has done long ago with narcosis. Evidently a simple chemical can put a 'soul'/'spirit' to sleep. Weak magic, pushed by buffoons!]
S3v3N
1 / 5 (2) Jan 06, 2016

Same here, it is worse than that "the soul is not made of matter". The LHC showed 2013 explicitly that any such magical idea simply can't exist, if you don't accept the implicit rejections by the existence of thermodynamics et cetera that shows our world is entirely non-magical.
[ctd]


I am not disagreeing with you, however, I will posit that saying something is settled science when 96% of the universe is apparently comprised of dark matter and dark energy, NEITHER OF WHICH HAVE EVER BEEN OBSERVED...Seems pretty magical to me.

Nothing moves faster than the speed of light, except for the interstitial space between everything.

Seems pretty magical to me.

Double slit experiment.

Seems pretty magical to me.

Not saying there's a god, not saying there isn't. That's a completely different issue. Just saying that whatever our current conception of the way things are *is*, it is completely insufficient to adequately explain what we are observing. Enjoy!
my2cts
5 / 5 (3) Jan 06, 2016
The matter without the breath of life from the living God will never become alive even if it is perfectly organized in 3d structure thanks to the efforts of intelligent beings.

Wrong. As Professor Frankenstein proved, it is just electrified protein.
my2cts
3.7 / 5 (3) Jan 06, 2016

I am not disagreeing with you, however, I will posit that saying something is settled science when 96% of the universe is apparently comprised of dark matter and dark energy, NEITHER OF WHICH HAVE EVER BEEN OBSERVED...Seems pretty magical to me.

Nothing moves faster than the speed of light, except for the interstitial space between everything.

Seems pretty magical to me.

Double slit experiment.

Seems pretty magical to me.

Clarke's third law: Any sufficiently advanced technology is indistinguishable from magic.

Just saying that whatever our current conception of the way things are *is*, it is completely insufficient to adequately explain what we are observing. Enjoy!

Except if we hypothesize DM and DE.
animah
5 / 5 (8) Jan 06, 2016
96% of the universe has never been observed

When you think about it, 96% of the volume of the earth has never been observed.

Yes, this definitely means we have a lot to learn about it.

But to suggest our fundamental understanding of it may be wrong sounds pretty pessimistic to me.
AGreatWhopper
2.4 / 5 (5) Jan 06, 2016
viko_mx1 /5 (7) Jan 05, 2016
the breath of life from the living God


Is what you feel on your neck all day as he rapes you in the asshole!
AGreatWhopper
2.6 / 5 (5) Jan 06, 2016
Why do religion trolls keep trolling in science comments & forums?


They troll everywhere but only here does the site make revenue from allowing conservative trolls (the driver is all the climate change articles), but having done that we get trolled with all their other favorite causes, from Sky Daddy to every brain damaged 19th century fantasy about electricity.

Case in point that holds most the variables constant is the PO forums. There trolls are subject to moderation just as on most sites and you'll not find any religion trolling. Same site, same people, same content. The difference is the bye conservative trolls get in the article comments.
Whydening Gyre
5 / 5 (1) Jan 07, 2016
The matter without the breath of life from the living God will never become alive even if it is perfectly organized in 3d structure thanks to the efforts of intelligent beings.

Wrong. As Professor Frankenstein proved, it is just electrified protein.

It doesn't help to use a fictional science guy to argue against a fictional god guy...:-)
qitana
not rated yet Jan 07, 2016
viko_mx1 /5 (7) Jan 05, 2016
the breath of life from the living God


Is what you feel on your neck all day as he rapes you in the asshole!


How do you know?
my2cts
5 / 5 (3) Jan 07, 2016
In fact living organisms are not just matter, but also the spirit and the breath of life. Our DNA also is not just matter. It has connection with the divine matrix.

The holy matrix there it is again.
Maria is the virgin matrix of the living god who is also his own son whom he had murdered.
I get it now.
Do I now get thrown in the lake of fire by the living god who is his own dead son ?
You are free to believe all this nonsense just don't use it as an argument in a scientific discussion.

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