Memes as extended phenotypes
jqhar...@my-dejanews.com
Jim Bowery has posted a bunch of fascinating stuff on memes as
extended phenotypes. I take his thesis to be that genes can, quite
indirectly but effectively, manipulate culture to influence
bodies carrying rival genes. He gives as examples various
racist or ethnic media stereotypes, such as the blonde woman
and tall, dark man as the paragons of romance, and how these
might influence mating patterns. He elaborates other specific
examples and implications he derives from this theory. See my
"Jim Bowery sampler" or his posts to these newsgroups.
Upon reading this idea and observing some pieces of culture
in its light, I've had one of the few "hit in the head with a
two-by-four" experiences since reading Dawkins himself. As with
Dawkins' ideas of the "selfish" gene, extended phenotype, and
memetics, combining the latter two ideas seems to have wide
applicability and explain many previous mysterious aspects of
culture.
I haven't seen anything from Dawkins himself combining these two ideas.
The combination in retrospect seems quite straightforward, since
any human artifact, whether a dam or a religion, has two
Dawkinsian interpretations: a meme or, like a beaver dam, an extended
phenotype. Human artifacts are both at the same time: they are
influenced and filtered by gene-created nervous systems, and are
thus extensions of the phenotype. At the same time plans for and
attitudes about artifacts are trasmitted from brain to brain, thus
have a memetic component. Such transmission means that the
epigenetic creation and filtering effects of one human can
influence the behavior of another, turning the target human to some
extent into an extended phenotype of the genes of the source human.
Has anybody else put these two theories together? References/pointers?
Incidentally, I would be surprised if there was not a memetic
as well as epigenetic component to the design of beaver dams,
caddis larva shells, and so on. Differences in design not caused
by local environmental conditions will have cultural and genetic
components. Has anybody tried holding the environment constant
to experiment on remaining design differences for such an
animal artifact?
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Eric Rietzschel
unnecessary and I don't believe Dawkins writes anything to that effect.
Rather, memes are supposed to be a *new* kind of replicator.
Linking memes to genes seems to force one into all sorts of difficult to
maintain positions.
Greetings,
Eric
John Edser
Eric Rietzschel wrote in message <77lntq$g4f$1...@darwin.ediacara.org>...
JE:-
Gene are linked to memes and memes are linked to organisms.
They are NOT independent replicating systems they are DEPENDENT
replicating systems. The "difficult to maintain positions" is just
reality, intruding into fantasy...
John Edser
Independent Researcher,
PO Box 266
Church Point
NSW 2105
Australia
Hemida...@my-dejanews.com
Considering the importance of distinguishing cultural evolution (based
perhaps on memetic changes) from biological evolution (as far as heritabilty
is concerned, based on genetic changes), I think your question is worth
asking.
I would consider, though, that memes probably have an effect on the
behavioral phenotype by fitting into some sort of general structural
cubbyhole, with its indirect genetic background. The general encoding of
memes (a concept IMO congruent with the concept of engrams followed by
Lashley and Hebb and that has generated research into synaptic plasticity and
its "model" system known as long term potentiation) should probably involve
some basic genetic events. This is not the same as saying that genes and
memes have a tight one to one correspondence, though.
Without neural structures for memes to propogate in, they would be much like
a virus without a host. Since the development of these structures has a
genetic component, memes are indirectly dependent on the genetic architecture
of the organism. This dependence could be so indirect that one could maintain
that genes and memes are separable and that biological evolution and cultural
evolution are independent processes.
(snip rest)
Scott Chase
Hemida...@my-dejanews.com
"John Edser" <ed...@atinet.com.au> wrote:
>
> Eric Rietzschel wrote in message <77lntq$g4f$1...@darwin.ediacara.org>...
> >Why state that memes have a genetic background? This is absolutely
> >unnecessary and I don't believe Dawkins writes anything to that effect.
> >Rather, memes are supposed to be a *new* kind of replicator.
> >Linking memes to genes seems to force one into all sorts of difficult to
> >maintain positions.
>
> JE:-
> Gene are linked to memes and memes are linked to organisms.
> They are NOT independent replicating systems they are DEPENDENT
> replicating systems. The "difficult to maintain positions" is just
> reality, intruding into fantasy...
>
>
I'm not sure I agree with you here. Would you say that cultural and
biological evolution are tightly linked? If so would you consider fads and
fashions as having some specific "cubbyhole" in the brain where they can
interact with their corresponding genes? Any dependence memes would have with
the genetic architecture would IMO be very indirect at best. I would consider
only that memetic encoding might depend on the genetic instructions for
neurotransmission and memory storage. These are fairly general processes
though. This would not involve a one to one gene/meme correspondence. Can you
correct me if I'm erring here?
My knowledge of memes is restricted to reading some Dawkins and some
introduction by Dennett and Durham so I'm not very familiar with the journal
literature in the field. I haven't had the time yet to read Lynch or Henson,
but would like to someday.
Eric Rietzschel
John Edser <ed...@atinet.com.au> schreef in artikel
<77o2n8$fgt$1...@darwin.ediacara.org>...
> JE:-
> Gene are linked to memes and memes are linked to organisms.
> They are NOT independent replicating systems they are DEPENDENT
> replicating systems. The "difficult to maintain positions" is just
> reality, intruding into fantasy...
How are memes linked to genes then? I am quite curious.
(I wouldn't deny the possibility of *some* memes being linked to a neural
configuration, which in its turn could be linked to a certain genetic
inheritance, but this wouldn't have to be a necessary condition for all
memes)
Dierk Haasis
>Has anybody else put these two theories together? References/pointers?
I sometimes think that Desmond Morris did -- well, actually he has not
since his ideas were developed and published long before Dawkins. But
if you reread today his *Naked Ape*, *Human Zoo* or *Intimate
Behaviour* Trilogy, and some of his newer books (*Christmaswatching*?)
with Dawkins ideas about memes in mind "Morris" seems to be a good
answer to your question.
--
John Edser
Eric Rietzschel wrote in message :-
>> JE:-
>> Gene are linked to memes and memes are linked to organisms.
>> They are NOT independent replicating systems they are DEPENDENT
>> replicating systems. The "difficult to maintain positions" is just
>> reality, intruding into fantasy...
ER:-
>How are memes linked to genes then? I am quite curious.
>(I wouldn't deny the possibility of *some* memes being linked to a neural
>configuration, which in its turn could be linked to a certain genetic
>inheritance, but this wouldn't have to be a necessary condition for all
>memes)
JE:-
You have to firstly consider replication logic.
Memes can be replicated independently of the organism's replication
ie outside the organism, as in books etc. However, like the DNA in
organisms, this means nothing, until they are actually "read",
by an organism and affect that organisms performance in some way.
Thus the selection of memes follows the normal Darwinian logic of
organism selection, and must provide for adult (fertile) organism
increases, to be selected for. However, memes can compete WITHIN
an existing population, in a very flexible way, because they are quasi
independent, of organisms. In the end any this "sub" selection of memes,
within this quasi independent mechanism, must lead to an increase in the
number of adult fertile forms, or the meme cannot ever be selected for.
Since all memes must affect organisms, via their brains, to be selected for,
then brains must have a genetic base to allow the reception, generation and
judgement of the efficacy of the memes. This genetic base will be mostly
a non additive epistasis between very large numbers of loci.
Geneticists don't like to term such epistasis as "heritable" even if it
is DNA dependent, since its just too complicated to measure and
it is shredded at meiosis. Such complex epistasis is rationalised
by Waddington's concept of genetic cannalisation. His pioneering
work is almost totally ignored today because gene centric Neo Darwinism,
does not find such truths very "comfortable" to live with, side by side
to its insistence of " individual" genetic selection (ie selfish genes).
John Edser
Independent Researcher
PO BOX 266
John Edser
Hemida...@my-dejanews.com wrote in message >>
>> JE:-
>> Gene are linked to memes and memes are linked to organisms.
>> They are NOT independent replicating systems they are DEPENDENT
>> replicating systems. The "difficult to maintain positions" is just
>> reality, intruding into fantasy...
>SC:-
>I'm not sure I agree with you here. Would you say that cultural and
>biological evolution are tightly linked?
JE:-
yes, very much so.
>If so would you consider fads and
>fashions as having some specific "cubbyhole" in the brain where they can
>interact with their corresponding genes?
JE:-
The genetic realtionship is most proberly a huge epistatic one.
Such epistasis is not normally considered "genetic" even though
its DNA dependent, because it is shredded at meiosis.
In the end what is "genetic" will depend on Waddington's views
of what is cannalised. In the end complex features of the organism
must become canalised to make any heritable sense of them.
>Any dependence memes would have with
>the genetic architecture would IMO be very indirect at best. I would
consider
>only that memetic encoding might depend on the genetic instructions for
>neurotransmission and memory storage. These are fairly general processes
>though. This would not involve a one to one gene/meme correspondence. Can
you
>correct me if I'm erring here?
JE:-
Its my view that we must get away from this "one on one" view to
make any headway in synthetic genetics and evolutionary theory.
"One on one", is ok, to find the gene but hopless in saying how
it works in context to selection, or even basic physiology.
Gene GROUPINGS is the real question here. This means, how
are individual genes, GROUP selected, since they are never
individually selected, and how do groups of genes allow
for the inheritance of meme reception, generation and efficacy.
Waddington pioneered both these questions which today
are ignored, because individual gene selection and "one on one"
gene causation, alone, dominates the field.
>My knowledge of memes is restricted to reading some Dawkins and some
>introduction by Dennett and Durham so I'm not very familiar with the
journal
>literature in the field. I haven't had the time yet to read Lynch or
Henson,
>but would like to someday.
JE:-
For me a meme is a very old idea, jingle-ized by Dawkins.
Its just how the ACTIONS of a body part may become repeated
in the next generation. Selection only selects actions, not morphology
and groups of genes code for such plastic morphologies, that limit
the set of actions termed "memes".
William Morse
jqhar...@my-dejanews.com wrote:
>Jim Bowery has posted a bunch of fascinating stuff on memes as
>extended phenotypes. I take his thesis to be that genes can, quite
>indirectly but effectively, manipulate culture to influence
>bodies carrying rival genes. He gives as examples various
>racist or ethnic media stereotypes, such as the blonde woman
>and tall, dark man as the paragons of romance, and how these
>might influence mating patterns. He elaborates other specific
>examples and implications he derives from this theory. See my
>"Jim Bowery sampler" or his posts to these newsgroups.
>Upon reading this idea and observing some pieces of culture
>in its light, I've had one of the few "hit in the head with a
>two-by-four" experiences since reading Dawkins himself. As with
>Dawkins' ideas of the "selfish" gene, extended phenotype, and
>memetics, combining the latter two ideas seems to have wide
>applicability and explain many previous mysterious aspects of
>culture.
Interaction between the two seems perfectly plausible, but I would be careful
about imputing too much specificity to the genetic component. First remember
that genes can only code for proteins, not stereotypes, and second remember
that "memes" (assuming one accepts the concept) have only been around in
any detail for several tens or possibly hundreds of thousands of years. Thus
evolving genes of sufficient specificity to code for a meme such as "tall,
dark, and handsome" is something of a stretch, and one would still have to
explain why the gene would code only for a tendency to embrace the meme
"tall, dark and handsome" rather than for a more "hard-wired" attraction to
tall, dark and handsome men.
>I haven't seen anything from Dawkins himself combining these two ideas.
>The combination in retrospect seems quite straightforward, since
>any human artifact, whether a dam or a religion, has two
>Dawkinsian interpretations: a meme or, like a beaver dam, an extended
>phenotype. Human artifacts are both at the same time: they are
>influenced and filtered by gene-created nervous systems, and are
>thus extensions of the phenotype. At the same time plans for and
>attitudes about artifacts are trasmitted from brain to brain, thus
>have a memetic component. Such transmission means that the
>epigenetic creation and filtering effects of one human can
>influence the behavior of another, turning the target human to some
>extent into an extended phenotype of the genes of the source human.
>Has anybody else put these two theories together? References/pointers?
>Incidentally, I would be surprised if there was not a memetic
>as well as epigenetic component to the design of beaver dams,
>caddis larva shells, and so on. Differences in design not caused
>by local environmental conditions will have cultural and genetic
>components. Has anybody tried holding the environment constant
>to experiment on remaining design differences for such an
>animal artifact?
I'm sure that some such experiments have been done, since animal behaviour has
been considered as a largely separate field from evolution until the recent
synthesis in sociobiology. You will find small differences in design in
caddis larva shells, considerable differences in beaver dams, and extensive
differences in higher primate societies. You will also find that even in the
case of caddis larva shells, the behavior while less variable is still
extraordinarily complex .
Yours,
Bill Morse
Eric Rietzschel
> JE:-
> For me a meme is a very old idea, jingle-ized by Dawkins.
> Its just how the ACTIONS of a body part may become repeated
> in the next generation. Selection only selects actions, not morphology
> and groups of genes code for such plastic morphologies, that limit
> the set of actions termed "memes".
This may explain some of the diagreement over this matter, since the term
'meme' is, I believe, more often used to refer to something much more
abstract than what you mean by it - see Dawkins.
Eric
John Edser
Eric Rietzschel wrote:-
>> JE:-
>> For me a meme is a very old idea, jingle-ized by Dawkins.
>> Its just how the ACTIONS of a body part may become repeated
>> in the next generation. Selection only selects actions, not morphology
>> and groups of genes code for such plastic morphologies, that limit
>> the set of actions termed "memes".
>ER:-
>This may explain some of the diagreement over this matter, since the term
>'meme' is, I believe, more often used to refer to something much more
>abstract than what you mean by it - see Dawkins.
JE:-
I just try to make some scientific sense of the unscientific and untestable
views
that Dawkin's serves up, to an unsuspecting general population, that
purchase his books. Dawkins has only some vague idea of what he thinks
a meme may be, which is just a vague as his "DNA fragment" that is
supposed to be most "selfish" bit of the genome, which he has also
failed to define so that it is testable.
Its the sure and tested way, to protect an "idea" from refutation.
Tim Tyler
: Dawkins has only some vague idea of what he thinks a meme may be, which
: is just a vague as his "DNA fragment" that is supposed to be most
: "selfish" bit of the genome, which he has also failed to define so
: that it is testable.
You seem to think Dawkins vague about what constitutes a gene. On the
contrary, in The Extended Phenotype he goes to /great/ lengths to
address in detail the question of exactly how much DNA constitutes what
he calls a gene.
When Dawkins says 'gene' he doesn't mean 'cistron', or any specified
length of DNA, but rather a quantity defined by the recombination rates of
the organism (if it is sexual). IIRC, he quotes that the gene is
"that which recombines with appreciable frequency".
--
__________
|im |yler The Mandala Centre http://www.mandala.co.uk/ t...@cryogen.com
Program: device used to convert data into error messages.
John Wilkins
|John Edser <ed...@atinet.com.au> wrote:
|
|: Dawkins has only some vague idea of what he thinks a meme may be, which
|: is just a vague as his "DNA fragment" that is supposed to be most
|: "selfish" bit of the genome, which he has also failed to define so
|: that it is testable.
|
|You seem to think Dawkins vague about what constitutes a gene. On the
|contrary, in The Extended Phenotype he goes to /great/ lengths to
|address in detail the question of exactly how much DNA constitutes what
|he calls a gene.
|
|When Dawkins says 'gene' he doesn't mean 'cistron', or any specified
|length of DNA, but rather a quantity defined by the recombination rates of
|the organism (if it is sexual). IIRC, he quotes that the gene is
|"that which recombines with appreciable frequency".
This is from Williams' 1966 - "I use the term `gene' to mean that which
separates and recombines with appreciable frequency" (1966: 20). He
further defined an "evolutionary gene" as "...any inherited information
for which there is a favorable or unfavorable selection bias equal to
several or many times its rate of endogenous change" (1966: 25).
I have an essay online that discusses this and the origins of Dawkins'
meme concept. Also see the essay by Gatherer in the subsequent edition.
Wilkins, J. S., 1998; What's in a Meme? Reflections from the perspective
of the history and philosophy of evolutionary biology. Journal of Memetics
- Evolutionary Models of Information Transmission, 2.
<http://www.cpm.mmu.ac.uk/jom-emit/1998/vol2/wilkins_js.html>
--
John Wilkins, Head, Graphic Production, The Walter and Eliza Hall Institute
of Medical Research, Melbourne, Australia
<mailto:wil...@WEHI.EDU.AU><http://www.wehi.edu.au/~wilkins>
I do not make errors; reality fails to live up to my expectations
John Edser
Tim Tyler :-
>: Dawkins has only some vague idea of what he thinks a meme may be, which
>: is just a vague as his "DNA fragment" that is supposed to be most
>: "selfish" bit of the genome, which he has also failed to define so
>: that it is testable.
>TT:-
>You seem to think Dawkins vague about what constitutes a gene. On the
>contrary, in The Extended Phenotype he goes to /great/ lengths to
>address in detail the question of exactly how much DNA constitutes what
>he calls a gene.
>
>When Dawkins says 'gene' he doesn't mean 'cistron', or any specified
>length of DNA, but rather a quantity defined by the recombination rates of
>the organism (if it is sexual). IIRC, he quotes that the gene is
>"that which recombines with appreciable frequency".
JE:-
And exactly what bit of DNA is that supposed to be,
so that we can count its replication rate IBD and test
his view against nature?
Dawkin's is trying to say, that the bit of DNA that
is the Neo Darwinian selectee, is that bit that "stays about
the longest IBD" without ever changing its base sequence.
What bit of the DNA is that then? Well that's easy to answer,
its just the DNA bases themselves......
Tim Tyler
: Tim Tyler :-
:>: Dawkins has only some vague idea of what he thinks a meme may be, which
:>: is just a vague as his "DNA fragment" that is supposed to be most
:>: "selfish" bit of the genome, which he has also failed to define so
:>: that it is testable.
:>TT:-
:>You seem to think Dawkins vague about what constitutes a gene. On the
:>contrary, in The Extended Phenotype he goes to /great/ lengths to
:>address in detail the question of exactly how much DNA constitutes what
:>he calls a gene.
:>
:>When Dawkins says 'gene' he doesn't mean 'cistron', or any specified
:>length of DNA, but rather a quantity defined by the recombination rates of
:>the organism (if it is sexual). IIRC, he quotes that the gene is
:>"that which recombines with appreciable frequency".
: JE:-
: And exactly what bit of DNA is that supposed to be,
: so that we can count its replication rate IBD and test
: his view against nature?
Roughly the average length of DNA preserved in meiosis, a quantity that
obviously depends on recombination rates within chromosomes.
I have no idea what 'test' you are proposing of Dawkins' view of things
by discussing replication rates - what Dawkins means by gene is defined in
terms of the units nature preserves heritable information between
generations in, so there's no possibility of his view not matching nature.
: Dawkin's is trying to say, that the bit of DNA that
: is the Neo Darwinian selectee, is that bit that "stays about
: the longest IBD" without ever changing its base sequence.
Not true! ;-)
: What bit of the DNA is that then? Well that's easy to answer,
: its just the DNA bases themselves......
You appear to be in need of re-reading the relevant chapter in "The
Extended Phenotype" where Dawkins discusses these ideas at some length.
The chapter is the one discussing 'units of selection' and
is called "The Active Germ-line Replicator" (Chapter 5).
I recommend paying particularly close attention to the sections where
Dawkins asks:
"Shall we write a book called 'The Selfish Nucleotide'? Is adenine engaged
in a remorseless struggle against cytosine for posession of locus number
30004?"
...and...
"So how large and how small a portion of chromosome is it useful to treat
as a replicator?"
...and...
"Is it possible to choose [the replicating unit] to be to small?"
To summarise Dawkins' view on the size debate (same chapter):
"Fragments of DNA qualify as active germ-line replicators. Where there is
sexual reproduction, these fragments must not be defined too large if they
are to retain the property of self-duplication. And they must not be
defined too small if they are to be usefully regarded as active."
Incidentally, Dawkins says the question he is interested in in this
chapter as follows:
The whole purpose of our search for a 'unit of selection' is to discover a
suitable actor to play the leading role in our metaphors of purpose. We
look at adaptation and want to say, 'It is for the good of...'. Our quest
in this chapter is for the right way to complete that sentence."
In other words, what Dawkins uses the term (unit of selection) for is
different from the way you (JE) seem to use the same term.
To me, you seem to be seeing selection as acting on what dies, whereas
Dawkins seems to be seeing selection as acting on what replicates.
--
__________
|im |yler The Mandala Centre http://www.mandala.co.uk/ t...@cryogen.com
God is real, unless explicitly declared integer.
Paul Gallagher
>: And exactly what bit of DNA is that supposed to be,
>: so that we can count its replication rate IBD and test
>: his view against nature?
>Roughly the average length of DNA preserved in meiosis, a quantity that
>obviously depends on recombination rates within chromosomes.
Have you ever seen anybody actually using the term "gene" to mean "the
average length of DNA preserved in meiosis"? As far as I can tell, even
when Dawkins uses "gene," he doesn't use his own definition.
70 years ago, when some people thought genes were particles arranged like
beads along a chromosome, Morgan called the gene the unit of recombination.
However, a few things have been learned about genes in the past 70 years,
among them that recombination by crossing-over can occur between any two
nucleotides, and therefore the unit of recombination is the individual
nucleotide. Moreover, the average length of DNA preserved in meiosis (the
average over what? the population? all living diploid organisms?) is
an odd way to designate the gene. How is it useful?
Paul
John Edser
Tim Tyler wrote:-
> >TT:-
>:>When Dawkins says 'gene' he doesn't mean 'cistron', or any specified
>:>length of DNA, but rather a quantity defined by the recombination rates
of
>:>the organism (if it is sexual). IIRC, he quotes that the gene is
>:>"that which recombines with appreciable frequency".
>: JE:-
>: And exactly what bit of DNA is that supposed to be,
>: so that we can count its replication rate IBD and test
>: his view against nature?
>TT:-
>Roughly the average length of DNA preserved in meiosis, a quantity that
>obviously depends on recombination rates within chromosomes.
JE:-
He is talking about the bits of DNA that do *not change* after
recombination and find their way into the next organism ie
as I said, those that persist across the generations.
Under gene centrics theory, which he uses, "the gene replicated" is
strictly defined as the same DNA coded bit, found in the next
organism, not just in the next cell ie genes replicated *IBD* and not
just genes replicated per se.
His view is of DNA base sequence persistence, and not of gene
replication at all. Replication is just an aid for persisting, for Dawkins.
The bit that persists across the generations *unchanged* is
the bit that is the Darwinian unit that is being selected and everything
else, proteins and soma etc are all just working for its persistence across
the generations. However, this is just genes replicated IBD if that DNA bit
must contain "genetic information" as well.
Some persist longer than others. What does this imply?
Does it mean that those that persist a shorter time are not
"selfish" at all but were really working for the more persistent?
If there are lots of these persistent units, how do they get along
when in the same genome?
>TT:-
>I have no idea what 'test' you are proposing of Dawkins' view of things
>by discussing replication rates - what Dawkins means by gene is defined in
>terms of the units nature preserves heritable information between
>generations in, so there's no possibility of his view not matching nature.
JE:-
Two important points here.
Firstly:-
He is NOT talking about "..the units nature preserves heritable
information between generations in " THESE are STRICTLY the entire
organisms. He is talking about the DNA bits that persist the longest
across the generations WITHIN these genes which are themselves,
within the organism to exist as genetic information in the first place.
Genes "persisting" does not happen at all, ever, no exceptions.
Only the REPLICATES of the DNA sequences of those genes are
being referred to by Dawkins, and they are very very strictly, carried
by genes replicated IBD. They are not the same DNA sequences,
they are copies IBD.
Genes IBD are strictly genes replicated in another organism ie genes
replicated *between* organisms and not genes replicated *within* an
organism. For any length of DNA "to persist the longest across the
generations", it must firstly be within a gene ( hox gene is a good
candidate) or it will quickly become mutated, if its neutral and then
its not the "same gene" at all and is lost.
It must then replicate itself into another organism, not just to another
cell within the existing organism even if its a sex cell within it. Only
then,
does it have any hope of "persisting" as Dawkin's intends it to do, as
the measure of selection.
Secondly:-
The way you are viewing Dawkins idea makes it non refutable, since
"if it persists, then it HAS persisted". Its called a tautology and it has
nothing to do with scientific thinking. The point is, it persists only
if it replicated IBD. Here you have two opposing testable possibilities
for scientific causation:-
Either
DNA persistence is caused by genes replicated IBD
OR
Genes replicated IBD are caused by DNA persistence.
Dawkins bit of DNA that is actually persisting, is itself persisting
via that genes replication IBD, and its replication is not caused
by the "gene persisting," as he is trying to suggest. The persisting
is caused by the replication IBD not the reverse.
Dawkins has reversed known cause and effect in nature to
produce his thesis, and it is just plain silly, but appears to have
gotten away with it.
In organism centrics, the organism survives ONLY to reproduce,
it does NOT reproduce to survive. Some people live to eat, others
eat to live, and they are exact opposites views of causation,
THAT CAN BE TESTED to refutation. Dawkins and gene centrics
in general, must make it crystal clear, what its testable thesis of
natural selection CAUSATION actually is, as Darwin did, before
their views can be regarded as any sort of science.
>TT:-
>You appear to be in need of re-reading the relevant chapter in "The
>Extended Phenotype" where Dawkins discusses these ideas at some length.
>The chapter is the one discussing 'units of selection' and
>is called "The Active Germ-line Replicator" (Chapter 5).
>"Fragments of DNA qualify as active germ-line replicators. Where there is
>sexual reproduction, these fragments must not be defined too large if they
>are to retain the property of self-duplication. And they must not be
>defined too small if they are to be usefully regarded as active."
JE:-
Exactly.
The phrase "usefully regarded as active" just means that they must
carry genetic information in themselves. Genetic information for what?
For the phenotype, which in turn acts for the good of that organism
which alone is selected.
Bases cannot be Dawkins selection units, because they carry no genetic
information in themselves. My suggestion that they could be was "tongue
in cheek". This was because, such bases do persist longer, than
any gene, or gene fragment. If persistence is NOT the criterion of
Darwinian selection, then something else must be.
Dawkins is stuck with DNA bits that code for a phenotype
ie that actually "do something" for the organism. They are replicated
IBD and selected from their phenotypes alone which in turn are
selected relative to the entire organism.
If his DNA fragment codes for a phenotype, then the phenotype ONLY
is selected for and NOT the DNA sequence itself. At this point the only
hope of that DNA fragment has of remaining an INDIVIDUALLY
acting selectee which is waht he is supposing, is that it relates only in
an additive way to all the other similar DNA seletees in that genome.
This is similar to Fisher's principle, and it just means that the selective
worth of the organism is strictly the SUM (not the multiple) of the
selective
worth of all the genes in that organism. This assumes that the organism
is just a loose population of genes!
Dawkins pays tribute to Fisher, in one of his
latest press interviews, attributing to him (and correctly so IMHO)
the origins of Dawkins logic, of his "selfish gene", stance.
Fisher as a person, was a eugenic bigot, who insisted that
an individual genes worth, has no relative contextual value,
but only an absolute value, in itself, no matter what other genes
are present in that genome and thus the fitness of the organism
is simply the "sum of its parts," or SUM of all its genes.
All racialists and social darwinmists have made the same claim
which originated from Mullers early work. Today we know better,
or should know better to suggest any such thing. I refer you to
one of the most important web sites on the net that deals with
C H waddington's efforts over 30 years ago showing just how
contextual all gene action really is.
http://zygote.swarthmore.edu/env5.html
Dawkins must say exactly what DNA fragments he is talking about,
and how these are divorced from organism selection ( which they are not),
in order to present, as he says he has done, a TESTABLE "new theory"
of selection to the world, and this he has failed to do.
>TT:-
>Incidentally, Dawkins says the question he is interested in this
>chapter as follows:
>"The whole purpose of our search for a 'unit of selection' is to discover a
>suitable actor to play the leading role in our metaphors of purpose. We
>look at adaptation and want to say, 'It is for the good of...'. Our quest
>in this chapter is for the right way to complete that sentence."
>In other words, what Dawkins uses the term (unit of selection) for is
>different from the way you (JE) seem to use the same term.
JE:-
Not at all. Dawkins, like myself, views selection to be caused by the
maximal replication of some SINGLE unit in nature. He is a Fisherian,
gene centric to the core, happy with Hamiltonian views of selection by
proxy, but I am a Darwinian organism centric theorist who dismisses
these views as a TOTAL reversal of actual cause and effect, in nature.
For Dawkins, it is the DNA fragment that persists IBD. For me it is the
maximal replication of what I term "Selectons". A Selecton is an organism
unit of selection, that includes the immature young of any species, as an
integrated TEMPORARY part of its parents soma, and supposes that only
adult fertile forms are maximised from the parents over the parents
lifespan.
Each adult organism maximises the numbers of reproductions of itself
before it dies and this is the single motor of Darwinian natural selection.
For Dawkins, its his UNDEFINED DNA fragment "persisting", that is the
single motor of natural selection in nature.
Dawkins, to his credit, has finally come to the conclusion that multiple
units of selection, as in gene and cell and organ and organism and
populations of organisms are not any rational or scientific formulation
of selection theory. Its not "and" its only "or" !
>TT:-
>To me, you seem to be seeing selection as acting on what dies, whereas
>Dawkins seems to be seeing selection as acting on what replicates.
JE:-
Actually its the opposite of what you suggest.
He sees selection, as what persists (survives across the generations).
I see it as what maximally reproduces itself WITHIN each generation.
He wants to emphasise the term " survive" which is only phylogenetic
survival, and this is not survival at all, but only replication.
I see strictly exact units, reproduced over an exact time unit, that
can be tested against nature.
The unit maximally reproduced is the Selecton and the time unit is its
lifespan. You have to count the total number of adults replicated from
each adult per lifespan of that adult, to obtain a measure of selection.
John Edser
Independent Researcher
PO Box 266
Church Point
NSW 2105
Australia.
Tim Tyler
: Tim Tyler wrote:
[Genes:]
: The bit that persists across the generations *unchanged* is
: the bit that is the Darwinian unit that is being selected and everything
: else, proteins and soma etc are all just working for its persistence across
: the generations. However, this is just genes replicated IBD if that DNA bit
: must contain "genetic information" as well.
: Some persist longer than others. What does this imply?
: Does it mean that those that persist a shorter time are not
: "selfish" at all but were really working for the more persistent?
It does not - they may be less persistent due to chance or adverse
selection.
: If there are lots of these persistent units, how do they get along
: when in the same genome?
By interacting with one another.
:>TT:-
:>I have no idea what 'test' you are proposing of Dawkins' view of things
:>by discussing replication rates - what Dawkins means by gene is defined in
:>terms of the units nature preserves heritable information between
:>generations in, so there's no possibility of his view not matching nature.
: JE:-
: Two important points here.
: Firstly:-
: He is NOT talking about "..the units nature preserves heritable
: information between generations in " THESE are STRICTLY the entire
: organisms.
You've read my sentence as though the 'in' in "the units nature preserves
heritable information in" is short for "inside". In fact I meant it to
be read in the same sense as "the units people measure mass in".
Organisms cannot /possibly/ qualify for this role as information in them
is not a 'unit' - it is scrambled with other information in meiosis.
Nor is it preserved across generations - each individual (identical twins
excepted) is genetically unique.
: Genes "persisting" does not happen at all, ever, no exceptions.
: Only the REPLICATES of the DNA sequences of those genes are
: being referred to by Dawkins, and they are very very strictly, carried
: by genes replicated IBD. They are not the same DNA sequences,
: they are copies IBD.
*You* use the term 'gene' as though it refers to a /particular physical
DNA/ sequence.
*I* use the term 'gene' as though it refers to the /information content/
of such sequences.
I presume it is also your view that a 'genetic algorithm' run inside a
computer is severly mis-named...?
: Secondly:-
: The way you are viewing Dawkins idea makes it non refutable, since
: "if it persists, then it HAS persisted". Its called a tautology and it has
: nothing to do with scientific thinking.
What nonsense ;-) You said that Dawkins notion of gene was badly defined.
This is not correct - he has defined it about as clearly as I can possibly
imagine in a whole chapter devoted to the subject in the book I promptly
referred you to.
I'm presenting Dawkins definition of what he means by the term 'gene'.
Definitions aren't /supposed/ to be testable scientific theories, they're
communication aids.
If I define a 'foot' as being twelve inches I don't expect you to come and
complain that my definition is tautological and that you can't see how to
devise an experiment which might verify that the number is really twelve
rather than eleven or thirteen.
Dawkins goes on to *use* his notion of a gene to propose all manner of
testable hypothesis, ranging from 'you can't make much sense of the
evolution of sex without taking a gene's eye view' through 'failing to
take a genes eye veiw or parasitism often causes researchers to miss
important phenomena' to 'kin selection was only properly understood when
it's genetic basis was figured out by taking the perspective of the genes
in organisms'.
: The point is, it persists only if it replicated IBD. Here you have two
: opposing testable possibilities for scientific causation:-
: Either
: DNA persistence is caused by genes replicated IBD
: OR
: Genes replicated IBD are caused by DNA persistence.
: Dawkins bit of DNA that is actually persisting, is itself persisting
: via that genes replication IBD, and its replication is not caused
: by the "gene persisting," as he is trying to suggest. The persisting
: is caused by the replication IBD not the reverse.
: Dawkins has reversed known cause and effect in nature to
: produce his thesis, and it is just plain silly, but appears to have
: gotten away with it.
This all seems a curious mis-portrayal of the gene-centric position.
:>TT:- [...]
:>"Fragments of DNA qualify as active germ-line replicators. Where there is
:>sexual reproduction, these fragments must not be defined too large if they
:>are to retain the property of self-duplication. And they must not be
:>defined too small if they are to be usefully regarded as active."
: JE:-
: Exactly.
: The phrase "usefully regarded as active" just means that they must
: carry genetic information in themselves. Genetic information for what?
: For the phenotype, which in turn acts for the good of that organism
: which alone is selected.
Genes change in frequency in populations. You can repeat that 'only
organisms are selected' all you like, but genes live and disappear from
view like any other biological object.
In what sense are genes 'not selected'. They're not selected /directly/
by the environment reaching inside organisms, spotting an AGGAGTCG
sequence and wiping it out. However genes code directly for proteins and
some proteins /are/ directly selected. 'Toxic' ones will often cause the
organism, and its genome to cease to exist, for example.
: Bases cannot be Dawkins selection units, because they carry no genetic
: information in themselves. My suggestion that they could be was "tongue
: in cheek". This was because, such bases do persist longer, than
: any gene, or gene fragment.
It was hard to believe that even you could think Dawkins so stupid as
to believe nucleotides to be useful as heritable units. However you /do/
seem to be under a number of other serious misapprehensions concerning his
views...
: If his DNA fragment codes for a phenotype, then the phenotype ONLY
: is selected for and NOT the DNA sequence itself. At this point the only
: hope of that DNA fragment has of remaining an INDIVIDUALLY
: acting selectee which is waht he is supposing, is that it relates only in
: an additive way to all the other similar DNA seletees in that genome.
No, no, not so. Dawkins has recognised from the start that genes interact
with other genes in a complex, non-linear manner. See his response to
/exactly/ this criticism from one S.J. Gould in the 'Notes' at the back of
the second edition of The Selfish Gene.
The whole straw-man idea that gene centrists believe that individual genes
are often/always responsible for individual features in organisms
probably stems from a popular misunderstanding of the term 'a gene for X'.
When biologists say this they mean 'the genetic basis of X' *NOT* "X has
one gene which is entirely responsible for X's development".
A gene can remain a 'selectee' /despite/ complex interactions with other
genes in the gene pool if it has *some* or /any/ statistical effect on
the part of the phenotype which is selected. It matters little what
genes it finds itself with in any particular body but depends mainly on
the overall frequency of the genes it interacts with in the rest of the
gene pool. Effects due to linkage can also be relevant.
If, on average, the gene finds itself in bodies with genes which
co-operate with it, and it's effects are positive then it may increase in
frequency. If it finds itself, on average, in bodies with genes which
go to great pains to suppress its effects then these bodies (and their
genes) will probably not do so well due to the warfare going on inside
them.
: Dawkins pays tribute to Fisher, in one of his latest press interviews,
: attributing to him (and correctly so IMHO) the origins of Dawkins logic,
: of his "selfish gene", stance.
: Fisher as a person, was a eugenic bigot, who insisted that
: an individual genes worth, has no relative contextual value,
: but only an absolute value, in itself, no matter what other genes
: are present in that genome and thus the fitness of the organism
: is simply the "sum of its parts," or SUM of all its genes.
: All racialists and social darwinmists have made the same claim
: which originated from Mullers early work. Today we know better,
: or should know better to suggest any such thing.
So let me get this straight: Dawkins ideas depend on Fisher's.
Fisher had some other ideas which you don't like. It therefore
folows that Dawkins also has these ideas.
Also, for good measure all 'social darwinists' and, their breathren ;-)
'racialists' get this treatment.
Further, it appears that the ideas that "individual genes have a net
'worth' in a population" and "genes only contribute in a purely additive
manner to organisms' phenotypes" have been somewhat muddled up here.
I can believe that Fisher held the former view, but can hardly believe
that any thinking person has ever held the latter view. Cases where
one gene's fitness depends on what other genes are present (e.g. in
sickle-cell anaemia) are very widely known.
: Dawkins must say exactly what DNA fragments he is talking about,
You mean you /still/ think he hasn't done so? What more can I do...?
: and how these are divorced from organism selection ( which they are not),
...nor does he claim that they are...
: in order to present, as he says he has done, a TESTABLE "new theory"
: of selection to the world, and this he has failed to do.
Well the world-view described by "the selfish gene" wasn't invented by
Dawkins. He largely popularised and clarified the work of Hamilton and
others.
:>TT:-
:>Incidentally, Dawkins says the question he is interested in this
:>chapter as follows:
:>"The whole purpose of our search for a 'unit of selection' is to discover a
:>suitable actor to play the leading role in our metaphors of purpose. We
:>look at adaptation and want to say, 'It is for the good of...'. Our quest
:>in this chapter is for the right way to complete that sentence."
:>In other words, what Dawkins uses the term (unit of selection) for is
:>different from the way you (JE) seem to use the same term.
: JE:-
: Not at all. Dawkins, like myself, views selection to be caused by the
: maximal replication of some SINGLE unit in nature. He is a Fisherian,
: gene centric to the core, happy with Hamiltonian views of selection by
: proxy, but I am a Darwinian organism centric theorist who dismisses
: these views as a TOTAL reversal of actual cause and effect, in nature.
Doesn't this make you something of a fruit cake? ;-)
: For Dawkins, it is the DNA fragment that persists IBD. For me it is the
: maximal replication of what I term "Selectons". A Selecton is an organism
: unit of selection, that includes the immature young of any species, as an
: integrated TEMPORARY part of its parents soma, and supposes that only
: adult fertile forms are maximised from the parents over the parents
: lifespan.
Right. To help to see your views more clearly, what about kin selection -
can organisms forgoe reproduction to assist relatives to reproduce?
: Each adult organism maximises the numbers of reproductions of itself
: before it dies and this is the single motor of Darwinian natural selection.
Does this mean that grandchildren, or inheritance of posessions by
grandchildren after a death is *not* relevant to natural selection?
/Surely/ if you're being consistent you should have:
'number of offspring * relatedness, as t -> 'infinity'...?
:>TT:-
:>To me, you seem to be seeing selection as acting on what dies, whereas
:>Dawkins seems to be seeing selection as acting on what replicates.
: JE:-
: Actually its the opposite of what you suggest.
[...]
: The unit maximally reproduced is the Selecton and the time unit is its
: lifespan. You have to count the total number of adults replicated from
: each adult per lifespan of that adult, to obtain a measure of selection.
Again, what about kin selection? If a daughter sacrifices her
reproductive potential to assist raising sisters, does that mean her
'fitness' is zero? What if these sisters were born before her?
--
__________
|im |yler The Mandala Centre http://www.mandala.co.uk/ t...@cryogen.com
Never hit a man with glasses; hit him with your fist.
t...@cryogen.com
p...@panix.com (Paul Gallagher) wrote:
> In <794r72$kog$1...@darwin.ediacara.org> Tim Tyler <t...@cryogen.com> writes:
>
> >: so that we can count its replication rate IBD and test
> >: his view against nature?
>
> >obviously depends on recombination rates within chromosomes.
>
> average length of DNA preserved in meiosis"?
I said 'Roughly the average' to avoid getting into messy details. As
meiosis is a non-random process, and crossover frequencies vary from locus
to locus on chromosomes, what constitutes a gene will also vary from place
to place.
Dawkins discusses the notions of 'Muton', 'Recon' to refer seperately to
units defined by the processes of mutation and recombination respectively,
but continues with his broader 'gene'.
> As far as I can tell, even when Dawkins uses "gene," he doesn't use his
> own definition.
He doesn't stand by what he wrote in the 'An Active Germ-Line Replicator'
chapter in the rest of his writings? Are you thinking of something specific?
> 70 years ago, when some people thought genes were particles arranged like
> beads along a chromosome, Morgan called the gene the unit of recombination.
...that's pretty much how Dawkins uses the term...
> However, a few things have been learned about genes in the past 70 years,
> among them that recombination by crossing-over can occur between any two
> nucleotides, and therefore the unit of recombination is the individual
> nucleotide.
You're using 'the unit of recomibination' in a different, and not very useful,
sense. Dawkins' discusses this at some length, and the fact that introns may
occur within expressed genes and other similar messinesses in the chapter I've
already cited.
> Moreover, the average length of DNA preserved in meiosis (the
> average over what? the population? all living diploid organisms?) is
> an odd way to designate the gene. How is it useful?
Firstly I said "Roughly the average" because in response to the question:
"how long is Dawkins' gene?". As an abbreviated answer, I stand by this.
Try to pin me down on it, though, and I'd say that genes differ in length
depending on the recombination frequency at the relevant point on the
specified chromosome. This is itself a variable quantity - but not so
variable as to lose its utility.
I hope I'm I relieved of the burden of explaining in detail why such notions
of what a gene is are useful. Dawkins has written enough on that topic
himself. -- __________ |im |yler
Death: the cure of all diseases.
Paul Gallagher
>> As far as I can tell, even when Dawkins uses "gene," he doesn't use his
>> own definition.
>He doesn't stand by what he wrote in the 'An Active Germ-Line Replicator'
>chapter in the rest of his writings? Are you thinking of something specific?
When he refers to a gene "for" some trait, it's implicit that he thinks
of the gene as a functional unit - which a strand of DNA that survives
recombination definitely need not be.
>I hope I'm I relieved of the burden of explaining in detail why such notions
>of what a gene is are useful. Dawkins has written enough on that topic
>himself. -- __________ |im |yler
Please explain. I don't see the usefulness of such notions.
I'll make a guess that the inspiration for defining a gene as the fragment
of DNA that survives meiosis comes from segregation analysis. Traits that
segregate in a certain pattern are considered to be genetic. The defintion
of the gene as a recombinatory fragment is then just a projection of the
operational limitations of segregation analysis onto the molecular gene.
Since the actual segments of DNA that recombine at meiosis vary, and since the
length of these segments is largely unrelated to the function of the genes,
defining a gene in terms of these lengths seems arbitrary. Among other
things, it means most genes are never replicated: if the gene is just a
fairly long stretch of DNA, it's very unlikely that an equal length of DNA
with precisely the same sequence will be present in the next generation. A
segment of DNA may be entirely unexpressed. In this case, a gene by this
definition may have no function. Defining a gene in terms of recombination is
like defining stars as the visible sources of light in the night sky. It's
translating a limit on our powers of observation, a bias in perception, into
our definition of the entities observed.
Here's an attempt to define a gene in molecular terms: an allele is a segment
of DNA at a locus, where a locus is either RNA-specifying or regulatory,
and a locus is defined by its position in relation to other loci.
However, this definition has problems:
Movable elements:
Some genes are movable (segments of DNA can move within and between
chromosomes and between individuals and species);
Introns:
Much DNA has no structural or regulatory role. In particular, introns
occur within a locus and the RNA that is transcripted from them is spliced
out. The same transcript can be spliced in alternative ways. Therefore,
there is no simple correspondence between a DNA sequence and an allele.
RNA editing:
Many kinds of mRNA editing occur. For example, U can be changed to C, and
C to U through amination and deamination in particular tissue types. If the
changes are great enough, it becomes ambiguous whether the DNA segment
that produced the transcript should be called the gene for the resulting
polypeptide, since the sequence of nucleotides in the DNA segment does
not correspond to the sequence of amino acids in the polypeptide.
One DNA segment, many loci:
Frameshift mutations occur. The reading of a segment of DNA begins is offset
by one or two bases, and an entirely different polypeptide is produced.
This means that the relationship of DNA segments to loci can be one-to-many.
Many DNA segments, one locus:
Many segments of DNA are repeated many times. The same locus may correspond
to many different positions on a chromosome.
The above list I got from Sahotra Sarkar. Philip Kitcher listed some
additional problems: pseudo-genes that are non-functional but structurally
similar to functional genes, and the question of whether and how much of
the regulatory DNA involved in the transcription of a DNA segment should be
included in the delineation of the molecular gene.
Paul
John Edser
Tim Tyler wrote in message :-
>:JE
>: The bit that persists across the generations *unchanged* is
>: the bit that is the Darwinian unit that is being selected and everything
>: else, proteins and soma etc are all just working for its persistence
across
>: the generations. However, this is just genes replicated IBD if that DNA
bit
>: must contain "genetic information" as well.
>: Some persist longer than others. What does this imply?
>: Does it mean that those that persist a shorter time are not
>: "selfish" at all but were really working for the more persistent?
>TT:-
>It does not - they may be less persistent due to chance or adverse
>selection.
JE:-
Then, you now agree that Dawkins gene concept requires individual
genetic phylogenetic persistence? This persistence may change
with selection? If so, then persistence is the result of selection and
selection is not the result of persistence. Science is a testable thesis
of cause and effect and that cause and effect is non reversible or the
thesis is turned into its anti thesis and one must exclude the other
or the idea is untestable and non scientific.
Dawkins has just reversed cause and effect, to sound different and
attract attention, just like a teenager who wears a mohawk haircut
(there is one every generation) and he , like the teenager, has
succeeded in a spectacular fashion, among a reactionary population,
starved for any real innovation and imagination within evolutionary theory.
There are no grounds to reverse the known cause and effect of
selection within nature. Darwin outlined them and they have been tested
again and again. In fact, Dawkin's and gene centroics STILL use
the organism centric term of, genes replicated IBD, and not just
the gene centric term of, genes replicated. Every time they use
IBD, gene centrics refutes iys own thesis.
>:JE:-
>: If there are lots of these persistent units, how do they get along
>: when in the same genome?
>TT:-
>By interacting with one another.
JE:-
I see.
Are those individual genetic interrelations, dependent or independent
interrelations, within that individuals genome?
>:JE:-
>: He is NOT talking about "..the units nature preserves heritable
>: information between generations in " THESE are STRICTLY the entire
>: organisms.
>TT:-
>You've read my sentence as though the 'in' in "the units nature preserves
>heritable information in" is short for "inside". In fact I meant it to
>be read in the same sense as "the units people measure mass in".
JE:-
Genes are units of heritability, but these units are NOT combined in
a simple additive way. The individual is not the sum of the genes
that are within itself. Thus the unit of genetic information is the unit of
genetic combination, AFTER epistasis not before epistasis, as Neo
Darwinistic gene centrics keeps insisting it is within SYNTHETIC genetics.
Note that "the gene" within ANALYTICAL genetics, is only a correlation
of one DNA length with one phenotype and the SHORTHAND that
"x is a gene for y", instead of "x is correlated to y" has been taken as a
"literal truth" within gene centric synthetic genetics and is just silly.
The
only escape route for this view, is to insist that epistasis is additive,
because only this, "papers over", this epistemological error and
may then, possibly, allow independent gene selection.
>TT:-
>Organisms cannot /possibly/ qualify for this role as information in them
>is not a 'unit' - it is scrambled with other information in meiosis.
>Nor is it preserved across generations - each individual (identical twins
>excepted) is genetically unique.
JE:-
Most heritable information does not reside within each gene; it resides in
COMBINATIONS of these genes. Despite what genes you inherit, you
mostly still have a head, hands and eyes etc etc typical of your species
and this information, which appears generation after generation, is not
the simple sum of the genes in the genome it is a complex multiple of
these genes.
>:JE:-
>: Genes "persisting" does not happen at all, ever, no exceptions.
>: Only the REPLICATES of the DNA sequences of those genes are
>: being referred to by Dawkins, and they are very very strictly, carried
>: by genes replicated IBD. They are not the same DNA sequences,
>: they are copies IBD.
>TT:-
>*You* use the term 'gene' as though it refers to a /particular physical
>DNA/ sequence.
>*I* use the term 'gene' as though it refers to the /information content/
>of such sequences.
>I presume it is also your view that a 'genetic algorithm' run inside a
>computer is severly mis-named...?
JE:-
The "genetic information" is different to the "individual genetic
information
contained within each gene".
The individual "same gene" produces the "same polypeptide", but from
here on up, the combinations of polypeptides to make enzymes etc is
totally contextual and non summing. For a simple analogy compare
the way information is stored within written language. Imagine each
DNA base to be a letter and each word to be a gene. Mostly, but not
always,words (genes) combine to form sentences (phenotype
morphologies like fingers and eyes etc). I can just write "cat" but that
conveys limited information. If I write "The cat sat on the mat" or
"The cat fell into the sausage machine mincer" both put the cat into
differing contexts that is not simply additive for the words involved.
The information of "cat" stays exactly the same, and has to, to conserve
its information which is strictly restricted to the concept "cat".
Because the contexts are different, the results for the cat ( gene) are
very different within the two contexts. Lets suppose we separate the words
out from the sentences and jumble them into a pile ( the population deme ).
What can tell from this about the cat? Nothing, because we only have the
individualisedwords with ZERO context. Counting the freq of such genes
out of context,as if it was meaningful measure of selection IN ITSELF,
is just silly.
You may as well count the total freq of the word "thou" in shakespeer,
compared to "thee" and conclude that "thou" is a fitter gene than
"thee" because it is more freq and may even persist with increasing
freq from play to play. The context is where 99.9% of the information
resides (non additive epistasis ) and this is totally ignored as our
diligent gene centric uses Fishers 70 year old bean bag genetics vision,
supposing, "Oh, each gene has the about the same selective worth in
each body and epistasis is only about additive, acting as background
noise for each individual genes selective worth..." and only this
allows for the selfish gene assumption.
>:JE:-
>: Secondly:-
>: The way you are viewing Dawkins idea makes it non refutable, since
>: "if it persists, then it HAS persisted". Its called a tautology and it
has
>: nothing to do with scientific thinking.
>TT:-
>snip<
>I'm presenting Dawkins definition of what he means by the term 'gene'.
>Definitions aren't /supposed/ to be testable scientific theories, they're
>communication aids.
JE:-
They form an INDISPENSABLE part of any scientific theory, and yes,
they, like genes themselves, must be put into a context to "be tested".
No definitions, no context, no tests and no science.
Once again I ask:-
1) What is your view of Dawkins definition of a gene, since
this is the "unit of selection", or the unit that is persisting the
most over the generations ( not the unit of measure which
is the counting numbers, the unit being counted!).
2) How is that definition put into context so that it can be tested?
>TT:-
>If I define a 'foot' as being twelve inches I don't expect you to come and
>complain that my definition is tautological and that you can't see how to
>devise an experiment which might verify that the number is really twelve
>rather than eleven or thirteen.
The definitions here must refer to two separate concepts:-
1) The measurer, the agreed on convention of measure (inches and feet),
2) The measuree, that which is to be measured ( here the genes).
The unit of selection is the (2) not (1) !!
I don't care what you use for (1) as long as you
use it in a consistent (non rubbery ) manner.
>TT:-
>...'kin selection was only properly understood when
>it's genetic basis was figured out by taking the perspective of the genes
>in organisms'.
JE:-
Kin selection is a standing joke when used to explain
eusocials, which it considers its greatest theoretical victory.
Most haplodiploid eusocials have multiple male inputs
lowering the coefficient of relatedness to LESS than
a normal diploid (2n) relatedness for the sterile casts
within the one nest. E O Wilson is now talking about the
entire nest as being the unit of selection , which was the
original organism centric concept firstly provided to
explain the evolution of eusocials.
Termites which are not haplodiploid are strictly avoided
by Hamiltonian theorists, even if they make up the great
bulk in biomass for eusociality, because they are not
haplodiploid but normal 2n individuals.
Naked mole rats are eusocial (2n) mammals and are
just an extended family situation where sexual maturity
in most of the young has been inhibited by pheromones,
to allow better adaptation of the parents. In organism
centrics the young are a temporary part of the parents
soma until they become fertile themselves and the
genes in the young are at the mercy of the genes within
the parents until that time.
>:JE:-
>: The point is, it persists only if it replicated IBD. Here you have two
>: opposing testable possibilities for scientific causation:-
>
>: Either
>: DNA persistence is caused by genes replicated IBD
>: OR
>: Genes replicated IBD are caused by DNA persistence.
>
>: Dawkins bit of DNA that is actually persisting, is itself persisting
>: via that genes replication IBD, and its replication is not caused
>: by the "gene persisting," as he is trying to suggest. The persisting
>: is caused by the replication IBD not the reverse.
>
>: Dawkins has reversed known cause and effect in nature to
>: produce his thesis, and it is just plain silly, but appears to have
>: gotten away with it.
TT:-
>This all seems a curious mis-portrayal of the gene-centric position.
JE:-
I see, then explain to me, and all the readers EXACTLY,
how I managed to "mis-portray" the gene centric position here.
Just saying so, does not make it so and has nothing to do
with any discussion of the topic.
>:>TT:- [...]
>:>"Fragments of DNA qualify as active germ-line replicators. Where there
is
>:>sexual reproduction, these fragments must not be defined too large if
they
>:>are to retain the property of self-duplication. And they must not be
>:>defined too small if they are to be usefully regarded as active."
>: JE:-
>: Exactly.
>: The phrase "usefully regarded as active" just means that they must
>: carry genetic information in themselves. Genetic information for what?
>: For the phenotype, which in turn acts for the good of that organism
>: which alone is selected.
TT:-
>Genes change in frequency in populations. You can repeat that 'only
>organisms are selected' all you like, but genes live and disappear from
>view like any other biological object.
JE:-
Its a question of testable DIFFERENING cause and effect.
Either:-
The selection of genes (PLURAL) is because the organism is selected.
OR
The selection of the organism is because the gene (SINGULAR) is selected.
The former is gene centrics the latter organism centrics and
one is the exactr opposite of the other in selection theory.
Either the sun goes around the earth OR the earth goes around the
sun.
Because gene freq changes are the RESULT of organism selection
does not mean that organism selection is FOR such gene freq changes.
Either gene freq change is a cause or an effect or organism selection,
it can't be both.
TT:-
>In what sense are genes 'not selected'. They're not selected /directly/
>by the environment reaching inside organisms, spotting an AGGAGTCG
>sequence and wiping it out. However genes code directly for proteins and
>some proteins /are/ directly selected. 'Toxic' ones will often cause the
>organism, and its genome to cease to exist, for example.
JE:-
Yes that can APPEAR to be so. In reality it depends on modifier
genes and the effect is not independent but dependent. If its
dependent then the genes producing the effects, cannot ever be
individually selected in gene centrics sense, where that individual
gene keeps trying to maximise its phylogenetic persistence. That
one gene is being used by the organism in a contextual way and the
organism is DEFINITELY not being used by that gene, as gene
centric selection logic incorrectly insists and Dawkins popularises.
>:JE;-
>: Bases cannot be Dawkins selection units, because they carry no genetic
>: information in themselves. My suggestion that they could be was "tongue
>: in cheek". This was because, such bases do persist longer, than
>: any gene, or gene fragment.
>TT:-
>It was hard to believe that even you could think Dawkins so stupid as
>to believe nucleotides to be useful as heritable units. However you /do/
>seem to be under a number of other serious misapprehension's concerning his
>views...
JE:-
Not at all. I used the bases as "tongue in cheek" to show that the
concept of persistence is epistemologically false. Selection is
replication/reproduction driven of specific units of CONTEXTUAL
information ( the organism) not NON CONTEXTUAL information
( the gene) and this can be tested against nature and such non
contextual views are refuted.
>:JE:-
>: If his DNA fragment codes for a phenotype, then the phenotype ONLY
>: is selected for and NOT the DNA sequence itself. At this point the only
>: hope of that DNA fragment has of remaining an INDIVIDUALLY
>: acting selectee which is what he is supposing, is that it relates only in
>: an additive way to all the other similar DNA seletees in that genome.
>TT:-
>No, no, not so. Dawkins has recognised from the start that genes interact
>with other genes in a complex, non-linear manner. See his response to
>/exactly/ this criticism from one S.J. Gould in the 'Notes' at the back of
>the second edition of The Selfish Gene.
JE:-
Then his idea is dead in the water, because once information
becomes non additive contextual information then such parts
of any context cannot ever be selected in isolation, they are
GROUP selected. Genes are group selected, every time an
organism, is individually selected. Thus genes are used
by organisms (organism centrics) and organisms are NOT
used by genes (gene centrics) because individual genes are
group selected within the organism and their information is
dependent and contextual not independent and non contextual.
>TT:-
>A gene can remain a 'selectee' /despite/ complex interactions with other
>genes in the gene pool if it has *some* or /any/ statistical effect on
>the part of the phenotype which is selected. It matters little what
>genes it finds itself with in any particular body but depends mainly on
>the overall frequency of the genes it interacts with in the rest of the
>gene pool. Effects due to linkage can also be relevant.
JE:-
And that you have said, reduces genetic selection to
dependent group selection consistent with organism
centrics, and not the independent, individualised selection of the
gene centrics supposition. Here we have "selfish individuals"
and "selfless genes"NOT selfish genes and selfless individuals.
Dawkin's has it about as wrong as you can possibly ever get it...
>TT:-
>If, on average, the gene finds itself in bodies with genes which
>co-operate with it, and it's effects are positive then it may increase in
>frequency. If it finds itself, on average, in bodies with genes which
>go to great pains to suppress its effects then these bodies (and their
>genes) will probably not do so well due to the warfare going on inside
>them.
JE:-]
Yes.
Unless one genes selfish action compliments another genes selfish
action, then the two genes cannot ever be individually selected for within
the ONE body. It only takes ONE gene in ONE body to act in a non mutual
'selfish way" to destroy everything for all the other genes gains; its
called
dependence and it was this very same reason that the organism group
selection theory was rejected. The same logic applies to cancer cells.
Thus all genes are strictly dependent. Once dependent they
are tamed. Once tamed they serve only the body, which is the ONLY
focus of their individualised interests or they pay. Thus the body becomes
the focus of selection and individualised genes lose their SELECTIVE
individuality to the body, but maintain their information individuality,
like words do, because without it there is no dependent context.
Genes are the units of conservation and are not ever, no exceptions,
the individual units of selection that gene centrics calculates and
Dawkin's wrongly popularises.
>:JE:-
>: Dawkins pays tribute to Fisher, in one of his latest press interviews,
>: attributing to him (and correctly so IMHO) the origins of Dawkins logic,
>: of his "selfish gene", stance.
>
>: Fisher as a person, was a eugenic bigot, who insisted that
>: an individual genes worth, has no relative contextual value,
>: but only an absolute value, in itself, no matter what other genes
>: are present in that genome and thus the fitness of the organism
>: is simply the "sum of its parts," or SUM of all its genes.
>
>: All racialists and social darwinmists have made the same claim
>: which originated from Mullers early work. Today we know better,
>: or should know better to suggest any such thing.
>TT:-
>So let me get this straight: Dawkins ideas depend on Fisher's.
>Fisher had some other ideas which you don't like. It therefore
>follows that Dawkins also has these ideas.
JE:-
NO!
I am showing that eugenics bigotry is a product of an
ancient history thesis of how genes work, perpetrated
again today under the term "gene centrics" and
popularised by Dawkins.
If genes are contextual, dependent units of information,
then racialism and eugenics has no foundation. You
cannot point to a person and say, he has
the ALG gene ( like Steven Hwakin's) so HE is INFERIOR.
This genes action may well have given, within its context,
some of the genius that is Steven Hawkin. No gene has
an absolute value, its value is strictly relative to selection.
Thus all genes are group selected and are not individually
selected. Group selected object are altruistsic to their grouping
which in this case is the FERTILE organism they find themselves
within.
>TT:-
>Further, it appears that the ideas that "individual genes have a net
>'worth' in a population" and "genes only contribute in a purely additive
>manner to organisms' phenotypes" have been somewhat muddled up here.
JE:-
Yes, muddled by you and gene centrics, and not muddled by me
and organism centrics.
> TT:-
>I can believe that Fisher held the former view, but can hardly believe
>that any thinking person has ever held the latter view. Cases where
>one gene's fitness depends on what other genes are present (e.g. in
>sickle-cell anaemia) are very widely known.
JE:-
Dawkins is just Fisher made simple.
The selective worth of each gene is just the selective
SUM of all the genes in the genome. However, if its
more than just additive then its dependent and if its
dependent, gene selection follows the logic of genetic
group selection, not the logic of independent, individualised
gene selection as Dawkins, from Fisher, keeps insisting.
Here is an excerpt of a Dawkins interview:-
Dawkins interview:-
"Then there's the embryological gap. In our Darwinism we postulate
that there are genes for this and genes for that. We just leave the
embryological causal link between genes and phenotype as a black box.
We know that genes do, in fact, cause changes in phenotypes and that's
all we really need in order for Darwinism to work. But it would be nice to
fill in the details of exactly what goes on inside the black box".
From Skeptic vol. 3, no. 4, 1995, pp. 80-85.
C H waddington filled in" the black box" over 30 years ago for
selection theory considerations, but nobody wants to know about
that, thank you very much, because canalisation and assimilation,
produced from endless experiments, refutes gene centric selection
theory that still dominates Neo Darwinism today.
>:JE:-
>: Dawkins must say exactly what DNA fragments he is talking about,
>TT:-
>You mean you /still/ think he hasn't done so? What more can I do...?
JE:-
Is it just TOO MUCH to ask gene centrics to produce a testable
thesis of its assumptions?. Define the DNA fragment so that it can be
counted and tested. Define the selectee not the counting system
( units to the base 10 will be fine,,,,,).
JE:-
>: and how these are divorced from organism selection ( which they are not),
>TT:-
>...nor does he claim that they are...
JE:-
I see.
If selfish genes clash with selfish organisms then, who wins.
the genes or the organisms? I know who I will put my money on.
They have to be so divorced for ondividualised gene selection
to ever work at all.
>JE:-
>: in order to present, as he says he has done, a TESTABLE "new theory"
>: of selection to the world, and this he has failed to do.
>
>TT:-
>Well the world-view described by "the selfish gene" wasn't invented by
>Dawkins. He largely popularised and clarified the work of Hamilton and
>others.
JE:-
Its pedigree is from Muller and then Fisher. Hamilton came later.
>:JE:-
>:...Dawkins, like myself, views selection to be caused by the
>: maximal replication of some SINGLE unit in nature. He is a Fisherian,
>: gene centric to the core, happy with Hamiltonian views of selection by
>: proxy, but I am a Darwinian organism centric theorist who dismisses
>: these views as a TOTAL reversal of actual cause and effect, in nature.
TT:-
>Doesn't this make you something of a fruit cake? ;-)
JE:-
For people, who have been so badly taught that they cannot
ever conceive of the antithesis to their own totally biased thesis,
who parade themselves as "scientists" and have
no reputable, testable concept of the term "bi partisanship",
yes I appear to them as a "total fruit cake", what else could
I possibly expect ?
>:-JE:-
>: For Dawkins, it is the DNA fragment that persists IBD. For me it is the
>: maximal replication of what I term "Selectons". A Selecton is an
organism
>: unit of selection, that includes the immature young of any species, as
an
>: integrated TEMPORARY part of its parents soma, and supposes that only
>: adult fertile forms are maximised from the parents over the parents
>: lifespan.
>
>TT:-
>Right. To help to see your views more clearly, what about kin selection -
>can organisms forgoe reproduction to assist relatives to reproduce?
JE:-
Kin selection was discussed above.
Hamilton tried to show that kin selection causes genetic "altruism",
when in effect genetic altruism just causes APPARENT kin selection.
A parent looks after its young, and the young may be manipulated
to look after the parents and never become fertile themselves.
Genes flow naturally IBD via organism selection, that is all.
Organisms do NOT flow from genes replicating IBD.
>:JE;-
>: Each adult organism maximises the numbers of reproductions of itself
>: before it dies and this is the single motor of Darwinian natural
selection.
>TT:-
>Does this mean that grandchildren, or inheritance of posessions by
>grandchildren after a death is *not* relevant to natural selection?
>/Surely/ if you're being consistent you should have:
>
>'number of offspring * relatedness, as t -> 'infinity'...?
JE:-
Relatedness is caused via organism reproduction that
RESULTS in genes being replicated IBD.
The reproduction of genes IBD per se, does NOT CAUSE
ORGANISM RELATEDNESS.
Can you not see that the two above are in total conflict?
How do you propose we test them?
John Edser
Independent Researcher
PO box 266
Paul Gallagher
>No, no, not so. Dawkins has recognised from the start that genes interact
>with other genes in a complex, non-linear manner. See his response to
>/exactly/ this criticism from one S.J. Gould in the 'Notes' at the back of
>the second edition of The Selfish Gene.
>The whole straw-man idea that gene centrists believe that individual genes
>are often/always responsible for individual features in organisms
>probably stems from a popular misunderstanding of the term 'a gene for X'.
>When biologists say this they mean 'the genetic basis of X' *NOT* "X has
>one gene which is entirely responsible for X's development".
Even if if Dawkins' argument that you refer to were correct, it would
merely mean that genic models of selection are a possible way of modeling
selection. It would not follow that is the correct, best, or "most
parsimonious" way, as Dawkins claims.
The problem that gene interaction poses for genic selection models is
that selection is a causal process occurring in a population, selecting
among types of genes. Population-level causal claims are different from
individual-level causal claims. Whereas in individual-level claims we
may sometimes reduce a causal process to its component causes, in a
population-level claim we often cannot. For example, if spraying with a
pesticide kills 90% of a population of plants, when we discuss an
individual plant that survives, it is incorrect to say it survived because
it was sprayed with the pesticide. Instead, it survived in spite of
being sprayed, for some set of additional reasons. A population-level causal
claim therefore can require reference to a complex of causes.
This is easy to show mathematically. Except in special cases (lethal
dominants, heterozygotes intermediate in effects between both homozygotes,
etc.), whenever there is gene interaction, the genic selection model always
contains less information than higher level selection models. In many cases,
it is not possible to calculate the equilibrium state of the population
when only allelic frequencies are known, but it is possible when, for example,
gametic frequencies are known.
In particular, the selection coefficients at individual alleles, when
alleles interact, often are meaningless numbers, functions of the allele's
frequency in the population. If selection is considered to be a real
process or force in nature - not just a mathematical abstraction - the
concept of selection should describe a real cause of change in a population,
caused by a real property of some entity.
A useful analogy, which also undercuts some of the mystique of genes created
by talk about genes as "information", is to compare a gene to a family
name. Like genes, family names are immortal bearers of information. Like genes,
their frequency in the population changes over time for various reasons. They
live, while individuals die. Let's then say that we are lumbering robots
that exist to perpetuate our last names. Nonetheless, the reasons why family
names change in frequency in a population are almost always unrelated to any
particular characteristic of the name itself. The causes of their different
rates of reproduction need not lie solely in the properties of the name. It's
necessary to distinguish the causes of a process from its consequences. Even
when some property of the last name causes the survival or reproduction of
the person bearing it, it is necessary to distinguish the object selected
from the property for which it is selected.
It's useful to distinguish Dawkins' argument that replicators are
the unit of selection, which is essentially stipulative - he redefines
the unit of selection so that the term refers to a replicator - from the
long-standing empirical question of what is the unit of selection. The unit
of selection question is an empirical question, which should be distinguished
from Dawkins' attempts to redefine the unit of selection, and from
metaphysical questions such as, who benefits from selection, or whether
information is prior to matter.
Also, it's important to separate genic selection from the question of
kin selection. Classical population genetics models recognize both the
effects of individual genes and the possibility that selection will decrease
the mean-fitness of populations. As Hamilton among others recognizes,
kin selection does not require or imply genic selection. Kin selection is
a red herring in the genic selection debate. In fact, it can plausibly be
argued that kin selection according to Hamilton's model corresponds to the
selection of groups:
http://www.eeb.yale.edu/faculty/Rice/group.html
Further information can be found in Elliott Sober's The Nature of Selection.
Paul
Tim Tyler
: In <79n7dc$pr0$1...@darwin.ediacara.org> t...@cryogen.com writes:
:>> As far as I can tell, even when Dawkins uses "gene," he doesn't use his
:>> own definition.
:>He doesn't stand by what he wrote in the 'An Active Germ-Line Replicator'
:>chapter in the rest of his writings? Are you thinking of something specific?
: When he refers to a gene "for" some trait, it's implicit that he thinks
: of the gene as a functional unit - which a strand of DNA that survives
: recombination definitely need not be.
ISWYM. This "a gene 'for' X" terminology, while brief, and often accurate
has come in for some abuse recently, for example from Steven Rose in his
'Lifelines' book.
Dawkins is using the term as it's commonly in use by others - he's said at
one point that he doesn't mean it literally, that he doesn't mean only one
gene, or that these genes are 'for' the named trait exclusively.
IIRC, he recommends replacing "the gene for X" with the more longwinded,
(but clearer) "the genetic basis of X" - if in any doubt.
:>I hope I'm I relieved of the burden of explaining in detail why such notions
:>of what a gene is are useful. Dawkins has written enough on that topic
:>himself.
: Please explain. I don't see the usefulness of such notions.
To very briefly quote from the "The Active Germ-Line Replicator" chapter:
"We look at an adaptation and want to say: 'It is for the good of...'
Our quest in this chapter is for the right way to complete that sentence."
I can't make RD's arguments any better than he can - if you don't see the
usefulness of his term, and have not read his books then doing so is
the simplest remedy. If you /have/ read his books, but still see no
utility in his idea then I suspect that my chances of convincing you of
their validity here on usenet are low.
[functional definition of a gene...?]
If you want a functional definition of the gene that's fine. If you want
to say that a gene is a cistron that's fine as well. Different
definitions are useful in different contexts and so long as you're clear
about what definition you're using there are few problems.
Dawkins' idea of a gene is useful when considering evolutionary processes,
where the recombination frequency affects the linkage between genes. It's
useful there to consider items strongly linked together as a unit and
things which tend to separate in meiosis as distinct.
: Among other things, it means most genes are never replicated: if the gene
: is just a fairly long stretch of DNA, it's very unlikely that an equal
: length of DNA with precisely the same sequence will be present in the
: next generation.
That's not the idea - a gene is fairly short, not fairly long, and
a given stretch of DNA of comparable length /is/ exactly replicated in
meiosis with 'appreciable frequency' - from Williams' definition of what
constitutes a gene at any rate.
: A segment of DNA may be entirely unexpressed. In this case, a gene by
: this definition may have no function. Defining a gene in terms of
: recombination is like defining stars as the visible sources of light in
: the night sky. It's translating a limit on our powers of observation, a
: bias in perception, into our definition of the entities observed.
Not an analogy which does much for me. In what sense is the view of
genes I presented a 'bias in perception'? ;-)
Also, just because 'genes' in introns may appear to be 'entirely
unexpressed' in a particular organism doesn't mean that activity
at such sites has no evolutionary consequences.
Imagine three mutations are needed to transform protein A into protein B.
While protein A is expressed any /single/ mutation in protein A can be
selected strongly against. However if protein A is copied into an intron
then mutations can accumulate in it while it is not expressed. The
chances of the three consecutive mutations leading to protein B escaping
gene-repair mechanisms, under some circumstances, can increase.
Introns can also potentially contain genes providing resistance against
parasites and other possible goodies.
--
__________
|im |yler The Mandala Centre http://www.mandala.co.uk/ t...@cryogen.com
May all your hang-ups be drip dry.
Tim Tyler
: [Tim Tyler wrote:]
[very much snipping in what follows...]
: Science is a testable thesis of cause and effect and that cause and
: effect is non reversible or the thesis is turned into its anti thesis
: and one must exclude the other or the idea is untestable and non scientific.
You made arguments along such lines in your last post on a number of
occasions. The statements of the form:
Selection CAUSES persistence OR persistence CAUSES selection.
Gene replication CAUSES gene persistence OR gene persistence CAUSES
gene replication.
Organism relatedness CAUSES gene replication OR gene replication CAUSES
organism relatedness.
It seems to me that something like 'gene replication' is a complex causal
object. I think that, for almost any any reasonable X in biology a good
case can be made that gene replication is causally implicated in X, and
also that X subsequently goes on to modify gene-replication frequencies.
In short your arguments appear to be somewhat like:
EITHER the chicken CAUSES the egg *OR* the egg CAUSES the chicken.
When using messy biological objects in complex casual chains on
*both* siders of such equations the notion that such relationships are
either/or ones does not appear to be correct.
I also feel that the relationship between the one-line statements you
associate with the views of gene-oriented biologists, and the views they
present themselves, are rather weak.
: Note that "the gene" within ANALYTICAL genetics, is only a correlation
: of one DNA length with one phenotype and the SHORTHAND that
: "x is a gene for y", instead of "x is correlated to y" has been taken as a
: "literal truth" within gene centric synthetic genetics and is just silly.
It /would/ be "just silly" had anyone ever taken it as a universal
literal truth. Your apparent notion that it's widely believed to
always apply within gene-centric communities seems to me to be false.
[much snip]
: You may as well count the total freq of the word "thou" in shakespeer,
: compared to "thee" and conclude that "thou" is a fitter gene than
: "thee" because it is more freq and may even persist with increasing
: freq from play to play.
This analogy does not appear very fruitful to me - partly because
the same base-pair sequence at differing loci can have different effects.
[genes...]
: 2) How is that definition put into context so that it can be tested?
Tested compared to what alternative view? I'll attempt to provide an
outline of a test comaring gene-centric views with your organism-centric
ones, (to the extent that I understand the latter).
It seems to me (correct me it I am wrong) that organism-centric views
would predict that the elements of an organism's genome should work
together in harmony to produce the next generation of organisms -
with the result that organisms are harmonious wholes.
By contrast gene-centric notions suggest that, despite much co-operation
between genes due to a common shared method of getting into the next
generation, different nuclear genes within the same body /may/ have
conflicting interests and on occasion act to subvert the organism's
reproductive functions for their own benefit.
Now, genes which do this are known to exist: Dawkins referrs to them
as "outlaw genes". There's one well-studied example within
/Drosophilla/. These "Outlaws" ensure their own transmission into the
next generation despite loss in fitness of other nuclear genes (and
a decrease of the eventual 'reproductive output' of the organism which
bears it).
Such genes have been studied as a way to control pest populations.
Papers can have titles like "Selfish DNA: A sexually-transmitted nuclear
parasite" and still make sense. The world of the selfish gene is
/not/ a world of harmonious organisms maximising their personal
reproductive output.
I have difficulty in imaging how an organism-centric theorist can make
any sort of sense of this sort of material. It appears as though
parasites have invaded the nuclear DNA of organisms and managed to
reproduce themselves without ever turning into separate organisms, by
using their host's own redproductive channels. Such parasites don't care
if the organism has less children, so long as more copies of itself
are passed on. How can this sort of thing be happening if organisms are
harmonious wholes?
:>TT:-
:>...'kin selection was only properly understood when
:>it's genetic basis was figured out by taking the perspective of the genes
:>in organisms'.
[snip John's view of kin selection]
: In organism centrics the young are a temporary part of the parents
: soma until they become fertile themselves and the genes in the young
: are at the mercy of the genes within the parents until that time.
I see. Do organism-centric notions ever produce different predictions
about behaviour towards relatives from gene-centric notions?
For example, while I can imagine how you can view the parent-offspring
relationship as 'shared soma' what about the relationship between two
sisters? Do these 'share soma' in the same way that they share genes?
What if they are distant from one another and communicate only by mail?
What if they are both middle-aged? Is it possible to quantify to what
extent this 'soma-sharing' goes on on average?
[very much snip]
:>: Fisher as a person, was a eugenic bigot, who insisted that
:>: an individual genes worth, has no relative contextual value,
:>: but only an absolute value, [...]
:>
:>: All racialists and social darwinmists have made the same claim
:>: which originated from Mullers early work. Today we know better,
:>: or should know better to suggest any such thing.
:>So let me get this straight: Dawkins ideas depend on Fisher's.
:>Fisher had some other ideas which you don't like. It therefore
:>follows that Dawkins also has these ideas.
: NO!
: I am showing that eugenics bigotry is a product of an
: ancient history thesis of how genes work, perpetrated
: again today under the term "gene centrics" and
: popularised by Dawkins.
"eugenics bigotry" seems to me like another word for racism
which, I suspect, has existed for a very long time without
any supposed support from science. Further, science can
/only/ act to provide theories about the working of the world.
No scientific theory can offer moral council to human beings
on what course they 'ought' to pursue. Science can help
humans predict the consequences of their actions, but it
can't dictate what actions are chosen.
Stephen Rose also finds it necessary to mention Nazi death camps
in his "Lifelines" book. Whatever such notions have on the moral
fibre of the reader, I'm sure they do nothing but distract from the
scientific issues at hand.
I observe that "the survival of the fittest" being associated with
Nazi war crimes has been offered in support of creationism as opposed
to evolutionary theories. What makes you think your argument has any more
scientific worth than theirs?
: If genes are contextual, dependent units of information,
: then racialism and eugenics has no foundation. [...]
What has this argument got to do with science? You're saying that
your view is /right/ because it's /good/ and, "obviously" the good
*must* be true...? It seems that the argument has the form of an
appeal to political correctness. I find such arguments inappropriate
as a guide to scientific truth.
:>Further, it appears that the ideas that "individual genes have a net
:>'worth' in a population" and "genes only contribute in a purely additive
:>manner to organisms' phenotypes" have been somewhat muddled up here.
: Yes, muddled by you and gene centrics, and not muddled by me
: and organism centrics.
My perspective would be that I've just gone to pains to distinguish the
two concepts in my question after you had apparently reasoned your way
from "genes can have a net worth in a population" to "all genes can only
ever contribute in a linear manner to the phenotype"...?
:>I can believe that Fisher held the former view, but can hardly believe
:>that any thinking person has ever held the latter view. [...]
: Dawkins is just Fisher made simple.
: The selective worth of each gene is just the selective
: SUM of all the genes in the genome. [...]
Where does this come from? It appears to follow from it that
all genes in a given genome have the same 'selective worth'? Some genes
in a genome may cause fatal diseases - does this affect the 'selective
worth' of genes elsewhere on the genome? I can only think you're using
the term 'selective worth of a gene' in an /extremely/ unusual manner.
:>Well the world-view described by "the selfish gene" wasn't invented by
:>Dawkins. He largely popularised and clarified the work of Hamilton and
:>others.
: Its pedigree is from Muller and then Fisher. Hamilton came later.
If you're interested in history, I'd say that the notion that organisms
contain immortal essences, that bodies are transitory and unimportant
vechiles for an immortal thread of life, that humans have knowledge from
their ancestors, and that a part of them (excluding their personality)
can persist beyond death - can best be attributed to ancient Hinduism.
--
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|im |yler The Mandala Centre http://www.mandala.co.uk/ t...@cryogen.com
A Scarcity of Love.