Is Abiogenesis Feasible?

Conversation
1

Recently I gave a defense of an alkaline hydrothermal vent emergence of life theory. I went on the program looking for critical feedback but didn’t get much. I’d be interested in commentary from participants on this forum. There are already several things I noticed that were wrong, most of them minor but at least one more significant error, and I’ll list them here. If anyone is interested in this topic and would like to give their feedback, I’m all ears. It’s not the best presentation, there are a lot of ums and uhs and ahs from being over-tired, but I don’t think it’s terrible, either.

There’s a lot I didn’t mention during the program, but by the end of it I felt I had already given enough food for thought and I didn’t want to go on forever piling more on. Things I didn’t mention but that are also important include evidence for nitrogen fixation for the production of ammonia, the way that serpentinization mimics wet-dry cycles in prebiotic synthesis experiments by leeching up water as minerals precipitate, alternative mechanisms of polymerization such as adsorption to minerals and electrical interactions within the layers of fougerite clay, and the chemical pathway from serpentinization —> formic acid —> formamide for prebiotic nucleotide synthesis. These, among plenty of other things.

Here’s the video if you’re interested to give feedback:

Before anyone gets to it, since I am getting asked the question so frequently these days: NO, I am not a scientist. I have NO background. The only letters that could appear after my name are GED.

The errors I’ve noticed:

(1) I reference Korenaga as the geologist arguing for reduced Hadean atmospheric CO2 specifically from meteorite “impact ejecta weathering” but actually that’s Kadoya et. al. listed in the video description.

(2) I reference Wimmer’s (2021) “Energy at Origins” article on the role of pyrophosphate, but actually it’s another Wimmer paper published the same year “Irreversibility and Pyrophosphate…”

(3) I say Herschy (2014), but actually it’s Herschy (2016).

(4) I reference Kuhn et. al. (2014) on the role of acetyl phosphate in extant bacterial metabolism, but my point there is just dumb and irrelevant. I was too hasty trying to find a supportive article for a claim made by Nick Lane and misunderstood the point of this paper. Here it references acP-dependent acetylation of lysine residues, which inhibits the activity of enzymes in E. Coli, rather than specifically functioning as an energy currency. An actually relevant paper would be Silvina Pinna, “A Prebiotic Basis for ATP as the Universal Energy Currency” published, I think, 2021.

Besides this, as far as I can tell, the rest of what I say is legit, and would be interested to hear the thoughts of any others who follow abiogenesis research and take an interest in the topic. Thanks!

1 Like
2

Hi Dessel
The abiogenesis challenge is figuring out the origin of complexity. It is the same problem that the grand claims of evolutionary theory face which is understanding the origin of complexity. A living organism has to be able to metabolize energy and self replicate. This requires a complex system of molecules that work together.

A eukaryotic organism (yeast) needs to be able to manage chromosome structure and splice out spacers that separate coding DNA from non coding.

A vertebrate needs to be able to change its rate of cell division depending on current conditions of life like the process of going from a fertilized egg to a living child to being an adult human.

Darwin proposed a simple to complex model as a theory of how simple things become complex. There is currently little evidence to support this concept.

3

Haven’t watched the video yet, but in my experience the only “argument” against abiogenesis is “but how could?” followed by “AH-HAH” when you admit you don’t know, followed by the assertion that life’s origin is impossible based on unsubstantiated assumptions. That’s the essence of all arguments against abiogenesis.

They will spice it up with lots of assertions and factoids of dubious relevance, but at bottom that is the structure of all their arguments. There’s something they want to know how happened, they ask you to show how, you admit you don’t know, they then assert that it can’t happen because [insert dubious premise].

How did homochirality? How did ribose? How did X, Y, and Z? I don’t know. What follows from that? Nothing. They have nothing more than the “because you haven’t solved it yet you never will” non sequitur.
And they never deal with actual evidence for abiogenesis. They just ignore it even exists. Most of them don’t even know what this evidence even is or how it is evidence.

5 Likes
4

We simply don’t know of any feasible pathways for abiogenesis right now, at least with any certainty. However, history has shown that our ignorance is not a valid guide for determining what can or can’t happen in nature.

The one thing that I keep coming back to is what I would expect to see in the fossil record if abiogenesis did occur. I would expect to see the most simplest organisms showing up first in the fossil record, and that is exactly what we see.

4 Likes
5

Thanks to Bill Cole, Rumraket, and T aquaticus for your quick feedback.

To Bill: for the origin of complexity at the emergence of life I think non-equilibrium thermodynamics provides an answer, and I go over this a bit at the beginning of the talk.

To Rumraket: yep, that’s the SOP, and usually conjoined with a massive distortion of the actual state of the research in the lit.

To T aquatics: Most people feel that way, but I’m more optimistic about the AHV model. I think it’s made substantial progress and provides a comprehensive model even while some challenges remain.

1 Like
6

I don’t follow abiogenesis research that closely, so I will defer to you on that one.

Another possible route for research is looking for life on other planets. It isn’t unthinkable that we can find microorganisms somewhere on Mars or in the oceans of several moons orbiting Jupiter and Saturn. If we find different genetic and biochemical systems in life elsewhere in the solar system this would strongly point to abiogenesis being not only possible, but very probable.

3 Likes
7

Having now watched it I think Rebekah is somewhat confused, and I don’t understand what point she’s trying to make with the “all this had to come together so you’re kinda helping my side” statement. Alkaline hydrothermal vents exists and form naturally, and we have good reasons to think they would have existed in the Hadean and Archaean eons. We even have reason to think they might exist in the subsurface oceans of Europa and Enceladus. They’re not unlikely products of a lot of contingent circumstances, they’re inevitable on basically any rocky planet with plate tectonics and water. It is possible microbial life is ubiquitous in the universe, while complex multicellular life could be very rare. We just don’t know.

Overall I think you did really well.

I do have a couple of comments on some things you said:
Nucleotides/nucleobases might be a product of metabolic evolution (occurring in a system based on analog or compositional information instead of genetic polymers), rather than a sort of straightforward route of abiotic organic chemistry, so it’s not really clear to me how relevant the specific yield of nucleotide synthesis is given some hypothetical abiotic chemical reaction. Even if the yields aren’t that great (8% or whatever it was), it’s still possible there are selective mechanisms that can concentrate them while selectively separating them from other products.

With respect to the term “one pot” synthesis experiments I think it is a mistake to say these do not involve any human interference. In a one pot synthesis the human “interference” is the setting up of the initial conditions of the experiment (what to put into the one pot), which can of course involve completely prebiotically implausible choices for the reaction conditions, such as using already very complex, or highly purified, or homochiral molecules, in unreasonably high concentrations etc. etc. And they can also be interfered with by deciding when to stop the reaction and analyze the products.

1 Like
8

One concept that I think is often overlooked is just how massive the natural experiment would have been. Just on the Earth alone, we are talking about a reaction vessel the size of the oceans which ticked along for millions of years. We don’t even have to limit this to the Earth. We would also need to add all of the planets in the universe that could also carry out these reactions. It’s a bit foolish to think that a reaction in a 1 liter flask ticking along for a few days can properly model the actual natural experiment that occurred.

4 Likes
9

Nah I don’t think that’s a valid inference. Though the time and volume thing is definitely a valid point. The open ocean is not conducive to the origin of life(and almost no-one in the field is seriously suggesting it is). Any synthesis of organic molecules that might take place there is most likely going to be so dilute they’re more likely to break down again before they ever meet another relevant molecule to interact with.
It is not reasonable to imagine any degree of accumulation of organic precursors in the open ocean to such an extend you can get to any sort of spatially confined, replicating entity. The water and concentration problem are real problems and the open ocean is just too vulnerable to these. There are workable solutions to these problems in other natural environments we know would have existed on the early Earth.

You either need thermophoresis, gas-bubbles in rock fractures, or wet-dry cycles to concentrate organic molecules and bring them together to produce more complex entities. That implies a more restricted local environment such as hydrothermal systems, or inland lakes and pools.

But those systems are still much, much larger and much more long-lived in nature than any experiment in chemistry has ever been. A typical hydrothermal vent or pool has a volume several million times larger than any flask ever used in experimental prebiotic chemistry and they are active for tens of thousands to hundreds of thousands of years. And they have innumerable tiny cracks and pores, and minerals with enormous total surface area in which organic molecules, metal ions, and clays and so on can accumulate and react.

3 Likes
10

I used a massive overgeneralization which probably wasn’t for the best. “An entire oceans worth of environments conducive to these reactions” would probably have been a better description.

That’s the contrast I was trying to make.

4 Likes
11

@Rumraket: Thanks very much for your feedback. Your point about my complaint about low yields being mitigated by concentrating mechanisms like thermophoresis is spot on. Incredible that here I was talking about that very process and it didn’t occur to me to factor that in! I thought about it after the program, but too late!

When I’m talking about the one pot experiments involving no human interference, I mean that more in the context where creationists criticize the experiments by saying that “the researchers need to step in multiple times in order to get the products, showing you need intentional design to get them, rather than letting nature work on its own”. Agreed that there is a set-up performed by humans to initiate the experiment, but there are no further steps involved where the researcher has to “put their hand in” in order to guide the process in any which way. That’s also not to say that every step-in is illegitimate or unnatural, if you want to carry out an experiment to see what happens, say, when a river meets an ocean, the researcher could begin with the ocean set-up and then “step in” to introduce the materials in the river. Lame example mayhap but I think you’ll catch my meaning.

The pathway for nucleotide synthesis I used is based on the formamide pathway given by Saladino and then subsequently Doreen Niether who showed in 2016 that thermophoresis concentrates the formamide to appropriate levels, and then finally Kim & Kim, that paper I referenced and complained about during the talk.

Niether considers a lake environment and I actually like that best so far, based on Chatterjee’s (2016) model, entitled something like, “A symbiotic view of the origin of life at hydrothermal impact crater lakes”. In those freshwater hydrothermal systems thermophoresis would be operative. My concern currently is trying to figure out whether or not the formamide concentrations get too high. I’ve read for example that formamide decreases the melting temperature of DNA, so if you have a 50:50 formamide-water ratio it decreases the DNA melting temp down to 30-36 degrees C, which is right there at the temp my preferred model operates. If it’s the case thermophoresis accumulates formamide too well I’d have to scrap the pathway and seek an alternative model. I’ve also read from creationists that “formamide is toxic to living organisms” but the point made there (by Stadler and Tan) is extremely vague and not made properly relevant to OoL. FA can be toxic to some living organisms in a way that is totally irrelevant to OoL, just like how carbon monoxide is toxic by interfering with our blood system, a complex system totally absent at OoL. So I’m trying to work out some of these details about the pathway currently.

3 Likes
12

It would be interesting if scientists could actually synthesize life in the laboratory, under plausible prebiotic conditions. I don’t think that will happen any time soon, but it would be hilarious to see creationists’ responses and goalpost shifting. “But… it didn’t evolve into a frog!”

1 Like
13

They’d just say that intelligent scientists did it, so life requires a pre-existing intelligence.

7 Likes
14

There is a 10 million dollar prize if you can demonstrate functional genetic information forming by natural processes. The prize about 4 years old at this point and the organizer is @Perry_Marshall. Maybe he could join in and give you a status.

1 Like
15

On a related note, Lucy has a 10 million dollar prize for kicking the football.

image

8 Likes
16

I have been listening to your talk. Really good.

I was wondering what the clay was that you mentioned around 34:19 minutes in the video? I tried to google it, but I just can’t spell it correctly apparently.

1 Like
17

Hey Nesslig,

Thank you, but we’re gonna get much better! There were a few dumb mistakes and one important weakness in the argument I gave (relying on the formamide pathway for nucleotides), but the better responses are already available and I’m working on learning them.

The clay mineral I mentioned is fougerite, or green rust. It’s also been shown to reduce nitrogen/nitrate/nitrite to ammonia going all the way back to the late 90’s, beyond it’s mechanical properties, reduced interstitial water content, etc.

Also keep your eye out in the lit for two important papers that should be published in the next year: Harpreet Kaur 's work on palladium as a protometabolic catalyst and Stuart Harrison’s work on nucleotide synthesis. Frank Trixler on nucleotide synthesis, too, is another one to watch.

Last, if you haven’t yet, Chatterjee and Yadav are putting forward a specific hydrothermal scenario that I think is best, but it hinges on Dr. Russell being wrong about the non-existence of land, or continental crust, during the Hadean. Korenaga and Russell have been sparring in the lit and hopefully we’ll get some clearer answers on that in the next couple of years.

Thanks for listening, and happy reading!

3 Likes
18

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.