Oscillators and Replicators: A dialogue with Ella Hoeppner
ELLA: “You’re suggesting that self-organizing systems of oscillators existed before replicators, and were the real beginnings of life. But then the question becomes: where did these self-organizing systems of oscillators come from? The central question in biology is explaining the existence of design/adaptivity/knowledge. The theory of replicators explains how knowledge can be created from scratch, and no other explanation seems to be able to do that (at least, not in the context of biology). So if you’re suggesting that some system existed before replicators, you’re still left with the question: where did the knowledge behind the design of that system come from, if not from the evolution of replicators?”
CHARLIE: “I think you are right that the design/adaptivity/knowledge question has been answered since Wallace and Darwin by heredity and natural selection, which now we know includes genetic replication. The central question now in biology is really ‘what makes heredity possible?’ This is the question I am trying to answer.
Either way, we have a big leap of imagination to imagine the first life form. Don’t forget that an entire germ cell is heritable. The whole concept hinges on this observation. Every new life form inherits a part of the mother cell that carries on a cellular process as well as the DNA molecules. And most life is single-celled, where there is no distinction between soma and germline.
If you imagine that instead of a pool of replicators, that there was a pool of epistevolvers (self-organizing oscillating chemical reactions) contained in lipid bubbles that occasionally split in two as they absorbed more material, everything carried into the new membrane would be inherited, including the process of chemical reactions itself. Naturally, if some of these materials involved in the chemical reactions contributed to the survival of the resulting membrane-bound epistevolver, they would tend to become more common in the pool, even if they were just salts or proteins that were in the media. Eventually, through natural selection and evolution, these new bubbles would begin to contain more and more specific materials that promoted the survival and replication of the bubbles themselves, because the ones that did not would perish. At first these materials might just be some amino acids or the like, but eventually complex heritable molecules like RNA would evolve, then DNA. They would eventually become specific templates containing detailed knowledge.
Either way, life begins by accident. The replication-first idea is that by accident, a replication process began that evolved a self-organizing process. All I’m saying is that by accident, a self-organization process began that evolved a replicating process.
The difference is that my explanation accepts and includes everything explained by replication, but it also explains why life has many of the strange properties it has, like intelligence, memes, sleep, hallucination, exercise, chronic disease, aging, placebo, beauty, lateralization, symbiogenesis, microbiome, and environmental epigenetics. That’s why I keep saying that it’s really only visible from the top down. It is the big-picture unexplained characteristics of life that make epistolution a more plausible explanation than Neo-Darwinism alone.
If this is true, then we could build epistevolvers and re-create lifelike behavior without having to re-instantiate the whole history of life. Then the question of what the first life form looked like would be unimportant, purely an academic question, because we would be able to re-create life with new materials by arranging them to self-organize.
ELLA: “I’m a bit confused by your answer. These lipid bubbles that split in two and inherit the chemical reactions from their parents are a kind of replicator. Not DNA or RNA, but still replicators. So it seems like your argument is not so much that life began with something other than replicators, but just that the replicators with which life started were different from what most people imagine. And that’s a fair enough hypothesis, but it opens a bunch of new problems.
For evolution to work, replication needs to happen with a very high fidelity — the offspring of a replicator need to reliably be very similar to the original replicator. Otherwise, when beneficial traits randomly emerge via mutation, they won’t stick around for long. The nice thing about the hypothesis that the initial replicator was something like RNA is that it’s relatively easy for those kinds of molecules to replicate with high fidelity, since they store information digitally. I’m skeptical that a chemical-filled lipid bubble like you describe could really replicate with enough fidelity for much evolution to happen. Though I’m no chemist — if you have in mind a particular oscillating chemical process other than RNA replication that you think could replicate with sufficient fidelity, then maybe you’re right.”
CHARLIE: “You make a really important point, that the epistevolver I’m imagining could in some ways be described as a replicator. That’s really powerful and I’m glad you pointed that out. I agree that that makes my theory more congruent with conventional evolutionary thought, although it’s still causally reversed. I’m no chemist either, but I don’t have to be to see that the theory now forms a better explanation.
Now I’m wondering just what level of fidelity from generation to generation would be necessary for us to call it “evolution?” It’s hard for me to identify a firm boundary there. I would expect that the first life forms were wildly experimental in their forms, much more so than the DNA-based life we have now. I agree that among these bubbles there would have been a strong need for fidelity-carrying molecular networks (which could have eventually become RNA) among the molecules they carried if they were to persist, gain complexity, and inhabit more variable niches. In fact by taking your suggestion, now our theory explains how those networks became complex enough to replicate very faithfully. There was simply an evolutionary pressure to move toward faithful replication once you had accomplished epistolution.
Your suggestion is really brilliant. If we just state, ‘the first replicators were epistevolvers,’ then the conflict between our two versions disappears. Much of life, even today, is single-celled life that reproduces itself by dividing its whole body and conjugates directly with other cells of various types to exchange DNA. This style of life can’t really be said to have a fixed genetic program it’s carrying out. It carries out whatever spontaneous program that its entire cellular network (i.e. its body) and its environment tells it to, and attracts into itself because of that program the DNA that most helps it solve its survival problems. These organisms have lineages, but they can’t be said to have species, and even “strains” is a stretch. They are really, as Lamarck said, ‘only individuals.’
Why should it have been any different with the original organisms? Their entire bodies gave them the instructions to survive, and these instructions included the mandate to incorporate more and more faithfully replicating molecular networks into themselves. I see these faithful replicators as templates used for the purpose of epistolution. We can see that life is still attracting new sorts of templates into itself because we have recently experienced the invention of memes, which are new biological templates that the pre-human world never experienced before.
I think what’s really beneath this conversation is the insight that life, in order to persist, requires both continuity and requires change. Either way the ability to carry out continuity requires the ability to adapt to new circumstances. I don’t see this as introducing new problems into evolutionary theory at all but just acknowledging the problem that is already there, the problem that has made this question among the most difficult of our era.”
