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Chemical Evolution of Self-Replicating Molecules Observed In a Lab (nature.com)
New submitter n0w4k writes: Researchers at the University of Groningen have developed a self-replicating system able to not only pass hereditary information from one generation to another, but also mutate (non-paywalled link to the paper). It is a crucial step towards Darwinian evolution of abiotic species and artificial life. According to the authors and perhaps somewhat counterintuitively, in order to fully reach this goal, a death mechanism needs to be implemented in the system. Otherwise new species can only form but not disappear.
Self-replicating chemical systems have been widely studied before; some were even able to mutate. However, this discovery provides the first example of mutating replicators which are fully artificial.
Full disclosure: I am one of the co-authors; you can ask me if you have some specific questions or suggestions — maybe they can be implemented in the lab!
Self-replicating chemical systems have been widely studied before; some were even able to mutate. However, this discovery provides the first example of mutating replicators which are fully artificial.
Full disclosure: I am one of the co-authors; you can ask me if you have some specific questions or suggestions — maybe they can be implemented in the lab!
Where is your god now?
Seven puppies were harmed during the making of this post.
I would ask you to please don't let it get out of the lab.
You will probably reply: Bwahahahaha!
"The only good windmill is a tilted windmill."
Congratulations on your success n0w4k! I'm reading the article now.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
I don't get it... To me death is an obvious part of the life cycle, which is the base for evolution. What way of thinking can bring you to the point where you think evolution is possible without death?
n0w4k, first of all: congrats to you and your co-authors on this brilliant achievement ! Second: have you guys thought of the minimal amount of information necessary to represent each of the "elements" (or, as I'd rather say, "individuals") of your system ? I am very bad at chemistry, but not that bad as a programmer ;-) I'd actually love to try and replicate your experiment with pure information. Of course, this is only an idea. One would prolly also need to (en)code the system's environment...
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
All I'm seeing after clicking on the "non-paywalled link" is a page with a spinner icon near the middle and the text "Loading Enhanced PDF..." at the bottom. I'm using the latest version of the Chromium browser packaged for Debian GNU/Linux. It would be nice if there's a pre-print version available at the usual source.
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First of all n0w4k, congratulations to you and your team on your work at Groningen.
Every day, there's a lot of tech news, but this is what i consider truly nextgen science. It stands out.
Second, i clicked the link. I expected to find something insightful to read, but apparently its paywalled.
http://www.nature.com/nchem/jo...
This paywall is something i do not understand. So my first question now is, who descided this to be paywalled, and why? Where does the PDF money go?
Hivemind harvest in progress..
Like a low concentration of reducing agent. Or a colloidal mixture of particles with surface-attached reducing agents. Reduce the thiol bond back to SH and the structure would fall apart.
How can a death system be required, when you can have the later generations feed off of the previous generations.
So they don't die. they just get re-used by the offspring...
Eerily similiar, a self replicating and mutating system without DNA or RNA. Only like the Omega Man, man made. Yet in both stories it runs amok escaping the scientists lab.
What characteristics in a molecular system are required for it to be capable of reproduction?
What characteristics does this system have in common with DNA/RNA/Proteins(DRP)?
What's different from DRP?
Is there any possibility of a general theory which would allow prediction of possible alternate molecular systems capable of reproduction?
That ought to keep the lab busy for a while. :)
"A man can run out of breath before he runs out of questions." -- Lois McMaster Bujold
The fact you explicitly stated "in the lab" makes me concernedly wonder about the alternatives.
Table-ized A.I.
And all this fancy DNA and proteins that we see nowadays are the result of long evolution, starting from something much more simple.
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This is such a fundamental step towards answering one of the ultimate questions, I'm surprised this hasn't hit the front page of BBC news
Congratulations and thank-you to Jan, Elio, Piotr and Sijbren, keep up the good work!
Apparently these guys were too busy creating replicators to have watched Stargate SG1, because if they had they'd know that creating replicators was a seriously bad idea; now the sons-of-bitches have doomed us all.
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
$32 per copy otherwise. If you want free suggestions then provide a free readable piece.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
In optimization theory another way to look at diversification and death is the trade in algorithms between exploitation and exploration of a potential surface for local minima. Consider the 3-armed bandit problem where one of the slot machines has a better payoff ratio and one has a worse. Your initial search of a few pulls gives you a crude guess about which is the best and if you are right then it's a waste of resources to pull the lesser bandit arms in the name of exploring further. You should exploit it instead. But you may be wrong. Death wastes perfectly good species for the sake of hoping to find better.
However unlike the multi armed bandit when there is competition one can have Nash equilibria where no one is willing to deviate from a sub optimal strategy. Normally the solution to that in human endeavors is cooperation to jointly move to a Pareto preferred solution. However another approach is to deny information to the players such as including noise in their data. If you make reproduction inhomogeneously successful based on random externalities then one can move off Nash equilibria.
Have you seen evolution of Nash equilibria or is your potential surface downhill to optimal joint reproduction?
Some drink at the fountain of knowledge. Others just gargle.
I know exactly what would happen if I sent this link to my father, who is a creationist. He would tell me that it doesn’t prove anything. When I was a kid (and didn’t know enough to see through his poor logic), he addressed the issue of “what if scientists created new life in a lab.” He explained that having intelligent people spend millions of dollars to design a new life form is not the same as it happening by accident in nature. Of course he’s right, technically. We still don’t know how life originally arose, but what this does do is lower the bar for how complex something needs to be so that it can be considered the first or simplest living organism.
As I get older, I feel more and more like it’s silly to even have the debate. The only reason we’re even having this argument is because some ancient people wrote a book that we now consider to be sacred text, and lots of people have been taught to interpret it to mean that the earth can’t be very old.
One thing I find particularly amusing is where Ken Ham gets his “deal breaker” from regarding evolution. He points out that the concept of “original sin” precludes death prior to the first sin, since evolution implies death occurred before the first humans. Now, the thing is, a lot of the vehement creationists I have known are various kinds of protestant fundamentalists who are also rather anti-catholic. But it turns out that the doctrine of original sin is a extra-biblical catholic tradition.
Great to see a fellow chemist here! Yes, reducing agents indeed work as you expect and the group used this approach in other work. But we need to have replication AND destruction working at the same time. An issue that seems quite minor is that oxidation of thiols to disulfides is not 100% perfect. There are some side products (sulfenic and sulfinic acids) which accumulate if you constantly oxidize and reduce the mixture. So instead of recycling my colleagues have been working on supplying the 'food' molecules by flowing their solution into a vial containing replicators and withdrawing replicators 'out'. The first author of the paper (Jan Sadownik) calls it "death by withdrawal" ;-)
Still, it's not that easy to get everything right.
Selection (non-random death) isn't strictly needed for evolution, but without it the population will only evolve via drift. Selection definitely makes for a far more interesting evolutionary system.
I think selection should be still possible if death is fully random, but the fitness of the replicators (Addy Pross calls it dynamic kinetic stability - a chemist's perspective) can be still defferent because of different replication rates.
All of this doesn't say anything about the evolvability of the system, how long it will continue to evolve. I suspect the system described in the posted paper to have a limited evolvability, but the researchers don't seem to discuss the topic.
Indeed, it's evolvability is limited. We listed all possible replicators in the paper; there are 7 different compositions possible (13 different structures if you include sequence isomers). However, their mutation rate is quite high and cross-replication events happen quite often. This fits well into the quasispecies concept developed by Manfred Eigen. In our system we have two such sets of replicators where one is a descendant of the other.
This is not a reply to the original "OK, next!" --it is more "next".
Some years ago I gathered up and posted some amateur speculations about abiogenesis (in two parts). Whether or not any of them could be interesting or even useful, remains to be seen.
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If one part of the chain can read another and rewrite it according to the following rules then you have created life.
.i.e. The chain of codons needs to loop back on itself so it can read and change itself and do so in a way that ensures that there is always a part of it that contains the pattern that makes this possible, even if the position of the logic core pattern changes over time.
Read......Write
000.........0
001.........1
010.........1
011.........1
100.........0
101.........1
110.........1
111.........0
The simplest way to do this is to have it act like a shift register and read the last three codons on the right hand side to determine what codon to add to the left hand side, the read head part then moves to the left one place, and or the last codon on the right is deleted.
The initial start program needs to include the correct code to maintain a pattern for the computational core that implements the truth table so that the program does not eat itself.
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There are some strange, broken header pages which curiously enough do not link directly to the actual details. Here is the proper page:
http://www.nature.com.sci-hub.io/nchem/journal/vaop/ncurrent/full/nchem.2419.html
You've got some major formatting problems with your import into WP there, but on a quick scan, you seem to be getting the hang of understanding the interplay of chemistry, physics and geology that go into this complex problem. It's not publication-ready though.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Could you include a mineral with an -OH rich surface to scavenge these byproducts from the (solution) part of the system?
Oh noes! I'm channelling Cairns-Smith again! Clay minerals! Clay minerals! All is clay minerals! (ISBN-10: 0521346827)
[Ha ha. I actually saw AGCS lecture when I was an undergrad. Very passionate lecture, and at the time I thought that this was possibly one of the more important lectures of my life.]
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Pericles tried it. The results weren't good.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
I remember reading his stuff back in the mid-90s. It gave me a headache then, and I suspect it'll give me a bigger one now.
Props (or whatever the modern word is) for implementing a very simple version experimentally.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
For the medals, obviously. Gold, several inches across, and funded by explosives.
Yeah, that sounds a real good campaign slogan. Should be a real winner. I think you should sky-write it over the White House with your hand-controlled drone for maximum publicity. You'll be on TV!
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Well, as an Anonymous Coward, you'd be the perfect example of a completely unintelligent organisms to do the design.
I notice that you're too cowardly to associate your identifier with your reading incomprehension.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"