From: <Mario.Vaneechoutte@rug.ac.be>
Date: Thu, 17 Jun 1999 14:31:52 +0200
To: memetics@mmu.ac.uk
Subject: Re: Measuring Memes
Tim Rhodes wrote:
After reading your paper at http://allserv.rug.ac.be/~mvaneech/NYAS.html I
> think I understand what your getting at here. But I must admit that my
> regrettable lack of knowledge concerning the intricacies of organic
> chemistry is probably be keeping me from fully understanding your analogy to
> prebiotic chemical processes. (But I can't let a little thing like that
> stop me from giving it a shot, now can I?)
Don't bother too much about organic chemistry: my knowledge is very limited as
well, it is the general way of looking at things, I consider as important. de
Duve's book 'Vital Dust' (cited in the manuscript) however is magnificent
reading about the prebiotic world (also on evolution in general: of the best
I've read, except his embracing of the RNA-world, haha).
>
>
> So, as I understand what your saying (and in strictly layman's terms), the
> precursors to self-replicating cells were (in some sort of way) localized
> groups of constituent chemicals, some of which happened to encode
> information while others happened to be able to decode (or maybe
> transcript?) that information into another form. (enzymes?)
Somehow. I am thinking of a whole community of chemical reactions (e.g.
underneath a large membrane to avoid dilution). Some of these reactions are able
to produce nucleotides.Nucleotides (like (printed) texts) bring in a lot of new
possibilities:
i) The nucleotides are able to store information permanently (in culture: think
of ancient texts which still can be deciphered or of printed matter which can be
reread and be read by different people at different times),
ii) any kind of information can be stored (in culture: think of syntax and
symbols: a limited set of symbols enables to encode a large range of
information),
iii) a terrible lot of recombination is possible (in culture: think of how
science recombines ideas as they can be read from previous publications: spoken
language is much more limited here, e.g. because you lack a back-up for checking
the correctness),
iv) later proof reading is possible (in culture: editors, publishers, reviewers,
the author him/herself can reread and rework the text),
v) the information is there independent of ongoing metabolism/interaction (see
previous points about permanence), that is why so much recombination is
possible. If you free information carriers from the burden of self replication,
the information they contain can be recombined over and over again, avoiding the
COSMIC-LOPER problem (see manuscript and quote from Benner in previous mail).
Science can proceed so fast, basically because of the availability of printed
texts, I think, since printed texts add to a society all these very interesting
characteristics of permanent information carriers with unlimited informational
content.
vi) A society which starts to use such information will have more possibilities,
will develop new ways of doing things (forgetting the old ones and thus becoming
more and more dependent on this information (see e.g. Y2K problem, see how we
have to go to school for the best part of our lives to be able to survive in
this information society, see how we all know only a few specialized tricks
relying more and more on others for all the other tricks, ...). The society will
start to develop more and more around this information and its carriers and its
processors. I guess that's how the cell became an inevitable event.
Some other remark: most of you speak of mutated memes and mutational events, but
what really happens is recombination of memes. What happens in our brain (and in
science) is not that much mutation of memes (ideas), but continuous
recombination of ideas. Creativity is actually not creating new things, but
recombining old things. This recombination is much more potent than sexual
recombination whereby only two lines of information come together at each
recombination event. In brains, science and technology, many different lines of
knowledge can come together continuously.
In the RNA-world hypothesis, the first individual cell is the result of
individual molecules replicating always better. In the model above, I try to
forget about individuals and I try to imagine what a whole community can do. At
some instance unexpected (but almost inevitable) things can come out, like a
self replicating entity.
> Because this
> wasn't yet a self contained unit, the coded information didn't have to
> include instructions for making the enzymes(?) that could decode it, and as
> such had a greater freedom to vary without running up against variations
> which would adversely effected its ability to get itself copied. (Close so
> far?)
Perfect. The problem with natural selection early, as in the RNA-world, is that
the only information which is valuable is the information which says 'this will
let me copy faster than others'. But when you realize that the most simple cell
known contains 2000 genes with very very different fucntions, whereby none of
these genes itself contains sufficient information (far from) to enable self
replication, you readily can see how the RNA-world will have problems in
creating such diversity, given the need to also encode for ever faster self
replication of the putative self replicating genes. Searching mutational space
through natural selection among molecules will be virtually impossible. Imagine
that Einsteins' ideas got lost simply because some neighbour had many more
children. If culture had to proceed by differential survival of self replicating
ideas, we would go i) very slow and ii) would not be able to search many ideas,
since only ideas which enabled fast self replication would win the game.
>
>
> After the cell became an enclosed unit, only those variations that also
> preserved the ability to produce all the necessary decoding enzymes could be
> functionally viable.
Well, I imagine that physical closure of membranes leading to cells happened
many times (e;g. because such physical closure happened to happen easily
mechanistically speaking), but that this only led to the first self replicating
cell after billions of such events. It was a (n inevitable) coincidence that one
day one of these cells contained all the information to replicate. So, the first
real cell had to have all these functions, or the first real cell was the one
who happened to have all the essential functions. Once you have this, you can
make as many errors as you like, given that at least one of the descendants is
still capable of duplicating. That is one of the powers of autonomous
duplication: it leads to exponential multiplication, leaving a lot of
experimental freedom (or: if you have thousands of offspring cells who cares
that 99, 99% of descendants are failures as long as some make it to the next
generation).(This exponential replication through autonomous duplication is the
reason why the RNA-world is appealing at first sight. However, it seems
impossible to go from self replicating RNA molecules to a complex cell, as I
tried to explain - and for many more reasons).
> So that the amount of variation possible in early
> cells would have been significantly less than when encoding and decoding had
> been accomplished by separate entities.
I don't understand this
>
>
> (Again, please excuse me if I'm complete slaughtering your idea here 'cause
> I don't fully grasp the chemical processes involved. I hope you'll correct
> me if I have.)
>
> So, if I have all that right (?), you go on to see the relationship between
> memes and brains to be similar to that before the enclosed cell--where the
> encoded information doesn't need to include instructions for its own
> replication because another agency (the brain) takes care of that part of
> the process.
I hardly can believe it, but finally someone seems to understand what I am
trying to explain since a few years. Thanks for the effort. Ideas do not
replicate themselves. If they are replicated successfully, it is because they
can rely on an already existing world of brains. Of course they can have
characteristics which make them being replicated preferentially. Some
nucleotides may have been replicated preferentially, for several different
reasons. Jokes, good recipes, novel insights, intriguing hypotheses, ideologies
confirming your self image or promessing eternal life, threatening and
promessing chain letters all will be replicated easily.
>
>
> Assuming I've understood all that correctly, my question is this: Do we have
> any examples of kind of prebiotic situation you describe from which we might
> be able to extrapolate (and possibly make projections about) the
> evolutionary rates for the analogous memes?
I am afraid I can't do so, also because I have problems in understanding the
question.. What do you want to learn? Could you explain again? I don't know
whether the following answers your question:When I look at the evolutionary rate
of knowledge increase, I only can observe how it increases - each time
exponentially - with
i) symbolic spoken language (since 200 000 years, my guess, based on
archeological findings of cultural artefacts, including the origin of burial
rituals, which indicate to me the possibility to think about the far away
future, something I can imagine only to happen when you have language),
ii) written language (since some 5 000 years ago, leading to pyramids, Greek
philosophers, ...),
iii) printed language (since some 500 years ago, at least in W. Europe (since
longer in China, but maybe they were hampered by the kind of symbols they use))
leading to science,
iv) electronic language: computers and Internet (let' say: since some 5 years
ago).
The possibilities for storing information, reproducing it copy true, recombining
it (think of discussion lists and websites: much faster and powerful than
printing and exchanging scientific publications), replicating it at higher rates
(compare a monk, a press and bulk email), etc. etc. always increase, thereby
exponentially increasing the speed with which knowledge is gathered.
> Could you provide some, if such
> exists? (Preferably in as dumbed-down a language as you can muster.)
See above?
>
>
> Hoping you've been patient so far.
> -Tim Rhodes
Truly my pleasure.
-- Mario Vaneechoutte Department Clinical Chemistry, Microbiology & Immunology University Hospital De Pintelaan 185 9000 GENT Belgium Phone: +32 9 240 36 92 Fax: +32 9 240 36 59Mario.Vaneechoutte@rug.ac.be
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