Non-Living Replicators: Let's just list as many as we can!

[articulett]

I disagree but I don't think I want to pursue this. I note, however, that the journal of memetics seemed to have died becasue of the number of people who share my doubts.
I would be more interested in your opinions on two related questions
1. Are genes replicators?
2. Are replicators a necessary and/or sufficient condition for evolution?

1. Yes
2. Yes (though an environment of some sort is necessary for the "selection process") Example--if a virus irritates your lungs causing you to cough and spew it's DNA in cough droplets --and those droplets land in someone else's eyes or nasal passages--that virus will have a nice little trick that allows it to get a flying jump start into the next replicator victim.

I don't know about the journal of memetics, but the world and the concept is alive and well across the internet because it is USEFUL. I notice that those who dislike the term tend to be people who dislike Dawkins without actually ever having read him because they are affronted by the fact that he is an atheist. Perhaps memes don't exist for theists the way gods and souls don't exist for atheists.

 

[DRBUZZ0]

- Fission reactions? Self replicating once you hit critical mass. Or at least...at that point it will sustain self replication

- Recursive functions (within computer programs). They create more instances of themselves

-

 

[John Hewitt]

1. Yes (Genes are replicators)

I disagree. Genes seem to have no more capacity to replicate than do proteins.

2. Yes (replicators are necessary for evolution) - (though an environment of some sort is necessary for the "selection process") Example--if a virus irritates your lungs causing you to cough and spew it's DNA in cough droplets --and those droplets land in someone else's eyes or nasal passages--that virus will have a nice little trick that allows it to get a flying jump start into the next replicator victim.

Evolutionary ideas are used in several areas besides biology and, in some of them, one cannot identify any replicator. (Social evolution, epistemology, neurobiology and computational evolution being examples.) I would argue that it is replication of data, not the existence of a physical replicator, that is crucial to evolution.

I don't know about the journal of memetics, but the world and the concept is alive and well across the internet because it is USEFUL. I notice that those who dislike the term tend to be people who dislike Dawkins without actually ever having read him because they are affronted by the fact that he is an atheist. Perhaps memes don't exist for theists the way gods and souls don't exist for atheists.

I have read Dawkins and many worthless notions are alive and well without being useful.

 

[drkitten]

I disagree. Genes seem to have no more capacity to replicate than do proteins.

Really? So how did my daughter's genes for blue eyes come into existence if not by replication?

 

[drkitten]

Evolutionary ideas are used in several areas besides biology and, in some of them, one cannot identify any replicator.

Funny how inability to identify something doesn't mean it doesn't exist. We still haven't identified the Zodiac killer -- but his/her existence is undeniable.

 

[Wowbagger]

I disagree. Genes seem to have no more capacity to replicate than do proteins.

The difference being that genes have found a much wider variety of tricks to perform their replication. The cell, for example, is not, itself, a unit of replication. More accurately, the cell is a means for genes to replicate themselves. Multi-cellular life forms are a means for those cells to more effectively replicate their genes, (given the selection pressures they faced).

Proteins, by themselves, have not developed the ability to do that, yet.

Evolutionary ideas are used in several areas besides biology and, in some of them, one cannot identify any replicator. (Social evolution, epistemology, neurobiology and computational evolution being examples.) I would argue that it is replication of data, not the existence of a physical replicator, that is crucial to evolution.

The replicator identified in social evolution, has been dubbed the meme. Memes certainly do evolve, under selection pressure of the social environment they work in. Memes do not, strictly speaking, exist in a physical form, yet evolution plays a crucial role in their replication.
Any replicator, physical or not, that is subject to selection pressures, can be said to have the minimum properties necessary for evolution.

I have read Dawkins and many worthless notions are alive and well without being useful.

I hope you do not mean to imply Dawkins' ideas are not useful. (well, perhaps a few of them might not be: nobody is perfect)
But, in fact Dawkins' promotion of memes has been useful, for one thing, to explain why a lot of worthless notions are alive and well, without being useful.

 

[John Hewitt]

Really? So how did my daughter's genes for blue eyes come into existence if not by replication?

They were part of a cell, which replicated.

 

[drkitten]

They were part of a cell, which replicated.

So you admit that genes replicate.

 

[John Hewitt]

The difference being that genes have found a much wider variety of tricks to perform their replication. The cell, for example, is not, itself, a unit of replication. More accurately, the cell is a means for genes to replicate themselves. Multi-cellular life forms are a means for those cells to more effectively replicate their genes, (given the selection pressures they faced).

Proteins, by themselves, have not developed the ability to do that, yet.

No DNA and proteins etc. depend on one another for replication. Neither can succeed independently. You may want to note that Dawkins was not able to give a self-consistent, generally applicable definition of the gene.

The replicator identified in social evolution, has been dubbed the meme. Memes certainly do evolve, under selection pressure of the social environment they work in. Memes do not, strictly speaking, exist in a physical form, yet evolution plays a crucial role in their replication.
Any replicator, physical or not, that is subject to selection pressures, can be said to have the minimum properties necessary for evolution.

No replicator has been identified in social evolution. A name has been concocted for a supposed replicator. Since it was named to be analogous to the gene, the difficulty inherent in defining that entity raises serious doubts about the utility of defining a meme by analogy with a gene.

I hope you do not mean to imply Dawkins' ideas are not useful. (well, perhaps a few of them might not be: nobody is perfect)
But, in fact Dawkins' promotion of memes has been useful, for one thing, to explain why a lot of worthless notions are alive and well, without being useful.

I was replying to your insinuation that I had not read Dawkins but, in any case, I do not find his promotion of the meme useful. In my opinion, both Popper and Toulmin discussed the evolution of ideas more deeply than did Dawkins and their work precedes his.
Plotkin, too has a better take on such matters, though his work was much later it is called "The Nature of Knowledge." My own work was also original and, I feel, significantly progressed the field.

 

[John Hewitt]

So you admit that genes replicate.

It was the cell which replicated. I think that was perfectly clear.

 

[drkitten]

It was the cell which replicated. I think that was perfectly clear.

And the gene replicated as part of the cell -- which makes genes replicators. I thought that was perfectly clear.

If you are claiming that genes are the only biological system that replicates -- well, that's patently false, but no one claims that.

If you claim that genes do not replicate, then you're clearly out to lunch.

And if genes do replicate, then they're replicators.

 

[John Hewitt]

And the gene replicated as part of the cell -- which makes genes replicators. I thought that was perfectly clear.
<snip>
If you claim that genes do not replicate, then you're clearly out to lunch.
And if genes do replicate, then they're replicators.

The cell replicates and in the process produces further copies of all its DNA and proteins etc. That no more makes a gene a replicator than it makes a protein a replicator - that is just an incorrect claim by Dawkins. The smallest object in biology that I know of that can replicate itself is a cell.

 

[drkitten]

The cell replicates and in the process produces further copies of all its DNA and proteins etc.

So you acknowledge that genes are replicators.

The smallest object in biology that I know of that can replicate itself is a cell.

I'd feel much more comfortable about this statement if you recognized that it's a statement of the limitations of your own knowledge and has nothing to do with the real world. I'm not convinced that "what you know of" in biology would actually impress my elementary/primary school teachers.

 

[John Hewitt]

So you acknowledge that genes are replicators.

No, on this point I'm saying about genes exactly what Dawkins, in "The Selfish Gene," said about them. Genes do not replicate, cells do that. He also speculated that, once upon a time, genes had been real replicators. I think his speculation was wrong.

 

[luchog]

How do you differentiate a “left sock” from a “right sock”?

Which side the toes are on

 

[Wowbagger]

The cell replicates and in the process produces further copies of all its DNA and proteins etc. That no more makes a gene a replicator than it makes a protein a replicator - that is just an incorrect claim by Dawkins. The smallest object in biology that I know of that can replicate itself is a cell.

And just how did a cell learn to divide itself, like that? Do you have a model of such replication, that is complete enough to compete with selfish gene theory?

Selfish Gene Theory seems to have many of its details worked out rather finely (although, strictly speaking, no one can be absolutely positive it is correct). In this theory, the ancestors of the genes replicated in a similar manner to proteins, except that some of the gene ancestors developed cells around them: those genes that were better protected from the environment reproduced more effectively, and then, through symbiotic relationships with various bacterium, eventually developed organelles, instead.
This would seem to make more sense, from an evolutionary point of view, than a cell developing genes, and then learning to split.

Cells can still be considered repicators, though, since they do, from a higher level, replicate. They are simply not the most fundamental level of replicator of life forms.

No, on this point I'm saying about genes exactly what Dawkins, in "The Selfish Gene," said about them. Genes do not replicate, cells do that. He also speculated that, once upon a time, genes had been real replicators. I think his speculation was wrong.

If you think it is wrong, can you provide another alternative, that fits the evidence as well or better?

No DNA and proteins etc. depend on one another for replication. Neither can succeed independently. You may want to note that Dawkins was not able to give a self-consistent, generally applicable definition of the gene.

Well, first of all, for his purposes, the exact borders of genes are not relevant, since he was talking in general terms, and nature did not supply such convenient borders, anyway: sometimes genes would overlap or come from discontinuous parts, etc.
Second of all, that book was written in the 1970s, and we have come a long way in identifying actual genes, since then.
And third of all, according to the testimony of most geneticists: Genes have a propensity to copy themselves more often than copy anything "useful" for the cell. Much of the length of DNA strands is complete waste.

This waste can better be explained through Selfish-Gene theory, than anything else I have heard. If you disagree, provide the alternative.

No replicator has been identified in social evolution. A name has been concocted for a supposed replicator. Since it was named to be analogous to the gene, the difficulty inherent in defining that entity raises serious doubts about the utility of defining a meme by analogy with a gene.

First of all, nature is not obligated to develop things that are easily delineable by humans. What separates one gene from another can be very fuzzy, but that does not mean the thought of it being a replicator is not useful. And, as I mentioned above, even given that, we are still able to find and map genes on the DNA strands.

Obviously, specific memes are even much more fuzzier to define, than that. But, the concept is still a useful model for thinking about social evolution. (although, it is still a controversial subject) Memes that are better at reproducing themselves survive longer, than those that do not. This has been demonstrated in many social contexts. And, those memes do not really have to be useful, at all, to their hosts, only to themselves.

I was replying to your insinuation that I had not read Dawkins but, in any case, I do not find his promotion of the meme useful. In my opinion, both Popper and Toulmin discussed the evolution of ideas more deeply than did Dawkins and their work precedes his.
Plotkin, too has a better take on such matters, though his work was much later it is called "The Nature of Knowledge." My own work was also original and, I feel, significantly progressed the field.

As a term, memes never had any prior general usage, were never given decent formal definitions and never really added anything. In other words, memetics is junk science.

In a nutshell: Memes evolved in parallel to the "plastic" (meaning pliable) nature of our brains: Some primate had a more pliable brain, and was able to learn from others slightly better. This lead to selection pressures where the primate would try to communicate lessons to others. Those with other pliable brains were able to learn more effectively, and communicate with each other more effectively. Memes evolved out of this spread of ideas: The more memes became useful to us, the more plastic our brains became, and the more plastic, the more memes were allowed to infiltrate.
Does your favorite alternative explain socialization as well or better than that?

Memetics, though not a perfect science (its contenders admit this), is far from junk, and in fact has objectively measurable evidence to support it.

 

[John Hewitt]

And just how did a cell learn to divide itself, like that? Do you have a model of such replication, that is complete enough to compete with selfish gene theory?

Yes.

Selfish Gene Theory seems to have many of its details worked out rather finely (although, strictly speaking, no one can be absolutely positive it is correct). In this theory, the ancestors of the genes replicated in a similar manner to proteins, except that some of the gene ancestors developed cells around them: those genes that were better protected from the environment reproduced more effectively, and then, through symbiotic relationships with various bacterium, eventually developed organelles, instead.
This would seem to make more sense, from an evolutionary point of view, than a cell developing genes, and then learning to split.

I don't entirely follow any of this. In speculations of this type, primordial genes are usually taken to be self-replicating bits of RNA - this is the RNA world. This is not worked out finely at all, just a shopping bag full of improbable speculations.

Cells can still be considered repicators, though, since they do, from a higher level, replicate. They are simply not the most fundamental level of replicator of life forms.

Cells do replicate, fact, it is not a matter of being allowed to so consider them. They are the smallest entities observed to do so independently - genes are not observed to replicate independently.

If you think it is wrong, can you provide another alternative, that fits the evidence as well or better?

Yes.

Well, first of all, for his purposes, the exact borders of genes are not relevant, since he was talking in general terms, and nature did not supply such convenient borders, anyway: sometimes genes would overlap or come from discontinuous parts, etc.
Second of all, that book was written in the 1970s, and we have come a long way in identifying actual genes, since then.
And third of all, according to the testimony of most geneticists: Genes have a propensity to copy themselves more often than copy anything "useful" for the cell. Much of the length of DNA strands is complete waste.

This waste can better be explained through Selfish-Gene theory, than anything else I have heard. If you disagree, provide the alternative.

First, it is a worthless theory that cannot define its most fundamental terms.
Second, molecular biology has not changed that much since the 70s, Dawkins published a second edition in '89 and he still publishes actively today, without altering his claims.
Third, your comments about gene copying refer to the kind of complex eukaryotes that emerged followng the Cambrian explosion - not to the simpler prokaryotes that formed early life.

First of all, nature is not obligated to develop things that are easily delineable by humans. What separates one gene from another can be very fuzzy, but that does not mean the thought of it being a replicator is not useful. And, as I mentioned above, even given that, we are still able to find and map genes on the DNA strands.

This is a matter of observation - there is nothing in this finding and mapping of genes to justify the claim that genes are replicators and nothing useful about the claim either.

Obviously, specific memes are even much more fuzzier to define, than that. But, the concept is still a useful model for thinking about social evolution. (although, it is still a controversial subject) Memes that are better at reproducing themselves survive longer, than those that do not. This has been demonstrated in many social contexts. And, those memes do not really have to be useful, at all, to their hosts, only to themselves.

In a nutshell: Memes evolved in parallel to the "plastic" (meaning pliable) nature of our brains: Some primate had a more pliable brain, and was able to learn from others slightly better. This lead to selection pressures where the primate would try to communicate lessons to others. Those with other pliable brains were able to learn more effectively, and communicate with each other more effectively. Memes evolved out of this spread of ideas: The more memes became useful to us, the more plastic our brains became, and the more plastic, the more memes were allowed to infiltrate.
Does your favorite alternative explain socialization as well or better than that?

My favourite explanations is Darwinian sexual selection with social structure as its phenotypic target. Yes I think it does.

Memetics, though not a perfect science (its contenders admit this), is far from junk, and in fact has objectively measurable evidence to support it.

I will look forward to your telling me what that evidence is.

 

[Wowbagger]

And just how did a cell learn to divide itself, like that? Do you have a model of such replication, that is complete enough to compete with selfish gene theory?

Yes.

Cool! Can you tell me more about it. Give me a link, or write up a nutshell overview? (perhaps better worded than any of my own?)

I don't entirely follow any of this. In speculations of this type, primordial genes are usually taken to be self-replicating bits of RNA - this is the RNA world. This is not worked out finely at all, just a shopping bag full of improbable speculations.

You are correct in stating that the "ancestors of genes" were within RNA strands (or closely akin to RNA). I probably should have put the word RNA in there, somewhere, but I was trying to ramble the basic gist off the top of my head, and forgot.

But, the structural system, (RNA or DNA or something else), is less relevant than the components on it that replicated.

Cells do replicate, fact, it is not a matter of being allowed to so consider them.

Well, I am not the authority who decides if something is really a replicator or not. Cells do replicate. Fine. But, when you say this:

They are the smallest entities observed to do so independently - genes are not observed to replicate independently.

You are not taking "jumping genes" into consideration: http://en.wikipedia.org/wiki/Transposon , for example.

First, it is a worthless theory that cannot define its most fundamental terms.

What terms can it not define? Gene? A gene is a fundamental unit of selection. Actual genes may not have strict borders: they can overlap, and be formed from discontinuous parts. And, their phenotypic effect, if it has any (not all of them do), can be hard to detect, as well, given all the complexity of embryology. But, that does not mean the gene has not been defined. It takes great care to measure them, but measure them, we can.
What other fundamental terms has he not defined?

Second, molecular biology has not changed that much since the 70s, Dawkins published a second edition in '89 and he still publishes actively today, without altering his claims.

Is there any reason why his claims should be altered, if they are still useful?

Third, your comments about gene copying refer to the kind of complex eukaryotes that emerged followng the Cambrian explosion - not to the simpler prokaryotes that formed early life.

Actually, last I read, the Cambrian "Explosion" was more like the Cambrian "Illusion". It turns out, on closer inspection, that no real dramatic change in life forms ever took place, there. What makes the Cambrian era unique is the amount of soft tissue that was fossilized, in a couple of places, which does not usually fossilize well. It was not really unique in being an explosion of new life forms. That idea is outdated.

Secondly, are you implying "junk DNA*" did not exist earlier? I think the more reasonable idea, from the scientific stand-point, is that all DNA was junk, at some point: Some of it just happened to induce phenotypes that lead to better replication.

(* of course, we just call it that, as a joke, because it has no apparent "purpose" from a human-centric point of view.)

This is a matter of observation - there is nothing in this finding and mapping of genes to justify the claim that genes are replicators and nothing useful about the claim either.

What about the presence of junk DNA? What about those jumping genes? What about the existence of pseudogenes (which may not necessarily be on a usable DNA strand)?

In the mapping of genes, it is useful to think of them as replicators, because it explains the various patterns and histories of their copies, throughout the strand.

It is also useful for explaining the evolution of the cell: Gene-like things came first, then the cell formed around them.
It should be noted that once cells started to form, the gene may have lost some of its ability to completely self replicate, as it started relying more on the cell to do that job. So, the cell becomes a vehicle for gene replication.

You said you have a different model that works as well. Tell me something about it, then.

My favourite explanations is Darwinian sexual selection with social structure as its phenotypic target.

Ah, yes. I will not deny that is a useful model. Just like group-selection is also a useful model. It may be useful, from certain levels of view. But, it does not get into the core foundation levels.

"Survival of the Species" (as a group) was, and to a certain extent, still is, a good way of thinking about adaptations, from a distant point of view. But, once you start examining things closer: first self-survival becomes more apparent. Then cell survival. And then, once you find what drives cell survival the most, you find it could very well be gene survival.

Social structure as the target of sexual selection, also looks good, from a distant point of view, and can still be useful, when examining societies at that granular stage. But, when you wish to see more detail, you discover that all those bits of information passed, back and forth, in a social network, can themselves, be thought of as replicators. These replicators, of course, exploiting the very "plastic" brains that were the product of selection (sexual or otherwise).

These are not necessarily mutually exclusive ideas. Just different ideas that work at different levels of examination.

I will look forward to your telling me what that evidence is.

Well, technically, I will admit that memetics is still more of a protoscience**, than a hard science. But, it is being studied via the scientific method, so it is neither junk science nor pseudoscience.
(** I should have used that word when I said "not a perfect science", in my last post)

Having said that, however, some memes can objectively be described as units of replicating ideas, such as catch-phrases, ear-worms (songs that get stuck in your head), fashions, artistic techniques, and even methods of building bridges.

There was once a paper I saw, in which a game of "Telephone" was analyzed by humans and a computer, and discreet units of copy and mutation were identified. I do not have time to find it, now. (I initially thought it was in here: http://users.lycaeum.org/~sputnik/Memetics/ but, upon initial perusal, I could not find it. Maybe I missed it, or maybe I will have to look elsewhere for it, later.)

I would like to continue this discussion, but I would rather do so in a separate thread devoted to it. I refer you to this one: http://www.internationalskeptics.com/forums/showthread.php?t=70215
Thanks.

 

[DRBUZZ0]

What about a robot which can mine metals, smelt, mold, mill, draw out wire, drill for oil, synthesize plastics, fabricate chips, etch boards and thereby assemble other robots which could do the same?

Okay....difficult. But not necessarily impossible.

 

[Wowbagger]

What about a robot which can mine metals, smelt, mold, mill, draw out wire, drill for oil, synthesize plastics, fabricate chips, etch boards and thereby assemble other robots which could do the same?

Okay....difficult. But not necessarily impossible.

That would be referred to as a "Clanking Replicator", but perhaps taken to an extreme. I think you are correct in calling them "difficult, but not necessarily impossible".

How about the next extreme: Robots spontaneously assembling themselves from basic replicatable components in the enviornment, which then go on to assemble robots like themselves?
Oh, wait, that's what life is!