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Jim Menegay · Guest

Before I started reading this group, I thought I had a pretty good
layman>s understanding of evolutionary theory and terminology. I
realize now that my background in the technicalities is inadequate.

Can anyone recommend a good graduate or advanced undergraduate textbook
on the THEORY of evolution?

I am not allergic to math. I would like to see some kind of treatment
of evolution at different levels; even if the conclusion turns out to
be that only one level (gene, organism, whatever) is important, I would
like to see this proved, rather than merely asserted. I want to see
treatments of ESS, kin selection, co-evolution of symbiotes, evolution
of signaling mechanisms, evolution of life histories, etc.

My primary interest is applying natural selection to origin of life, but
it is not obvious just which ideas may be useful here, so I guess I need
to know a little about everything.

Maybe I need several textbooks - population genetics + something else.
I>m open to suggestions. (That includes the suggestion that I should
just start reading the key papers from J.Theor.Biol or where-ever. Which
brings up a follow-up question - what journal should I go to for review
articles on evolutionary theory? I get much of my molecular and biochem
instruction from Ann.Rev.BioChem and from TIBS.)

And, while I have people thinking about textbooks, let me ask for
recommendations in some other fields:

Biochem - preferably a second-year or two-year text. One not focused
on human medicine. I want to know about enzyme mechanism and enzyme
evolution, plus have a reference book on molecules and pathways.

Bio-Organic chem - My current Organic reference is oriented to synthetic
chemists. I want to be able to look at a proposed reaction and have some
kind of notion of whether it is uphill or downhill and what the activation
energy is.

Bio-inorganic chem - I need to know more about co-ordination chemistry
and surface chemistry.

Molecular and Cell Biology - My copy of Darnell, Lodish, and Baltimore is
out of date. Plus, I would prefer something that gives equal time to
prokariotes.

Are there any textbooks on Molecular Evolution? Are they any good?

Thanks for the help.

Malcolm · Guest

"Jim Menegay" <jamenegay@ra.rockwell.com> wrote in message
[quote]
Before I started reading this group, I thought I had a pretty good
layman>s understanding of evolutionary theory and terminology. I
realize now that my background in the technicalities is inadequate.

You probably do have a reasonable understanding of the basic issues.[/quote]
Evolution is one of the simplest scientific theories to understand, however,
like any science, a large number of people are interested in it and try to
push our understanding as far as it will go. So just reading "The Selfish
Gene" will only start you on the road to being an evolutionary biologist.
[quote]
Can anyone recommend a good graduate or advanced undergraduate > textbook
on the THEORY of evolution?

Matt Ridley, Evolution. (This is quite a big volume, I think there may be a[/quote]
slim popular work by him of a similar name).
[quote]
I am not allergic to math. I would like to see some kind of treatment
of evolution at different levels; even if the conclusion turns out to
be that only one level (gene, organism, whatever) is important, I would
like to see this proved, rather than merely asserted. I want to see
treatments of ESS, kin selection, co-evolution of symbiotes, evolution
of signaling mechanisms, evolution of life histories, etc.

If you really want to be au fait with the issues, you need to look a[/quote]
journals. My favourite journal is Brain and Behavioural Sciences, because
every article is accompanied by critical comments from the peer reviewers.
It often has material on the evolution of behaviour, and often human
behaviour. TREE (Trends in Ecology and Evolution) is maybe a more relevant
journal.
[quote]
My primary interest is applying natural selection to origin of life, but
it is not obvious just which ideas may be useful here, so I guess I need
to know a little about everything.

These are two separate issues. Evolution is what happens after replicating[/quote]
entities have appeared. Now all known organisms use the same amino acids,
the same gentic code (almost), DNA and RNA, celular structure. What this
means is that the most recent common ancestor was itself a fairly
sophisticated organism. Using evolution, it is difficult to push back our
understanding beyond this ancestor, but it cannot have appeared at a stroke.
[quote]
And, while I have people thinking about textbooks, let me ask for
recommendations in some other fields:

I don>t really know much about the biochemical side of things, which is[/quote]
relevant to the origin of life. I>m just a ball-and-stick biochemist. I
doubt that you can learn enough chemistry to make a contribution to
understanding the origin of life simply by reading textbooks, though that
may be more a reflection of my inabilities as a student rather than the
difficulty of the subject.

John Edser · Guest

Jim Menegay wrote:-

JM:-
Can anyone recommend a good graduate or advanced undergraduate textbook
on the THEORY of evolution?

JE:-
Jim, I wish I could. None of them I have read deal with
absolute Darwinian fitness. All of them that I have read
take the Post Modern epistemological line: everything is
relative. Here relative fitnesses are only compared to other
relative fitnesses. A relative fitness must be compared to an
absolute fitness assumption and NOT to just an endless stream
of relative fitness assumptions.

JM:-
I am not allergic to math. I would like to see some kind of treatment
of evolution at different levels; even if the conclusion turns out to
be that only one level (gene, organism, whatever) is important, I would
like to see this proved, rather than merely asserted.

JE:-
The proof is not difficult. Selection can only maximise
the 1st fitness level that is independent. This
is just the 1st additive fitness level.

A basic of evolutionary theory is the absolute difference
between dependent and independent fitnesses. If you have
3 levels: A,B,C such that A is fitness dependent on B
but B is fitness independent to C, then B can only be
selected when B is maximised. Asserting that selection
at A can produce fitness altruism at B is absurd because
A is fitness dependent on B! Hamilton>s view that selection
at the gene level can force organism fitness altruism, a
view that entirely dominates Neo Darwinism, even today,
is absolutely wrong because all genomic gene fitnesses are
organism fitness dependent. Hamilton>s rule only compares
relative fitness counts. If gene fitnesses are dependent
on organism fitnesses then inclusive fitness can only describe
when a gene relatively increases. However that gene must become
absolutely reduced in fitness when it forces organism fitness
altruism, as Hamilton suggested it does. The simple fact is
that rb>c does not exclude the possibility that the
kin selected gene will be reduced to extinction because
it is organism fitness dependent. Hamilton left out a
term for absolute fitness within his rule, making it
just an arbitrary rule. Apparently for people like BOH
who reject Popper and are Post Modern in their thinking,
it is OK to suggest that just a relative gain remains an
gain, even when it becomes an absolute loss! Enron
accountants suggested exactly the same nonsense.
This is what current Neo Darwinism is reduced
to, via Post Modernism.

The relationship between AB and C is independent so that
they can only form a fitness association if the single
independent unit of fitness AB, and the other independent
unit of fitness C, produce mutual but not necessarily equal,
fitness gains via this association. Allowing ABC as one unit of
selection is what is known as classical group selection.
Originally organism fitness altruism was thought to be able to
be selected for by using it. A simple inspection of the logic
proves that it cannot. Both AB and C are _independent_ so
if fitness altruism is forced for say AB, then C units
have to compete for diminishing numbers of AB units
to pillage and AB units are also selected to fight back.
The cost of this war is more than it is worth to both
sides. Van Vallen>s view that nature is just ongoing warfare
is entirely wrong. Nature is all about reducing costs
and increasing fitness gains for independent units of
selection via fitness mutualisation. We mimic this logic
with trade. What the Neo Darwinist call "reciprocal altruism"
is actually fitness mutualisation where organism fitness
altruism is _entirely_ excluded. The problem is, Neo
Darwinism today, is run by the political left whose
mantra is "altruism". Previously it was run by the
political right: "might is right". Both are entirely
wrong. Science dies when basic epistemology is altered
to enhance a political bias.

Best Wishes,

John Edser
Independent Researcher

PO Box 266
Church Pt
NSW 2105
Australia

edser@ozemail.com.au

TomHendricks474 · Guest

Try Evolutionary Biology, Douglas J. Futuyma.

Tim Tyler · Guest

Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:

[quote]Can anyone recommend a good graduate or advanced undergraduate textbook
on the THEORY of evolution?

I am not allergic to math. I would like to see some kind of treatment
of evolution at different levels; even if the conclusion turns out to
be that only one level (gene, organism, whatever) is important, I would
like to see this proved, rather than merely asserted. I want to see
treatments of ESS, kin selection, co-evolution of symbiotes, evolution
of signaling mechanisms, evolution of life histories, etc.
[/quote]
There>s:

Evolution - Mark Ridley
Evolutionary Biology - Douglas Futuyma

The former book does a good job of the "evolution at different levels"
issue - IMO.

[quote]My primary interest is applying natural selection to origin of life, but
it is not obvious just which ideas may be useful here, so I guess I need
to know a little about everything.
[/quote]
I would suggest considering life as being *defined* in terms of being
an evolving system.

If you have no living system, there>s no evolution.

[quote]From this point of view, natural selection can only apply *after*
the origin of life - and thus can>t really be used to explain it.[/quote]

Natural selection is relevant to practically every aspect of life -
*except* its origin.
--
__________
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Tim Tyler · Guest

Malcolm <malcolm@55bank.freeserve.co.uk> wrote or quoted:

[quote]Matt Ridley, Evolution. (This is quite a big volume, I think there may be a
slim popular work by him of a similar name).
[/quote]
There is. One is a text book. The other is a book of collected papers.
Make sure you don>t get them muddled up...
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

Jim Menegay · Guest

"Malcolm" <malcolm@55bank.freeserve.co.uk> wrote in message news:<brj3mu$26sl$1@darwin.ediacara.org>...
[quote]"Jim Menegay" <jamenegay@ra.rockwell.com> wrote in message
[snip]
My primary interest is applying natural selection to origin of life, but
it is not obvious just which ideas may be useful here, so I guess I need
to know a little about everything.

These are two separate issues.
[/quote]
I don>t think so, for reasons given below.

[quote]Evolution is what happens after replicating
entities have appeared.
[/quote]
Replicating entities with reproducible variation, yes.

[quote]Now all known organisms use the same amino acids,
the same gentic code (almost), DNA and RNA, celular structure. What this
means is that the most recent common ancestor was itself a fairly
sophisticated organism.
[/quote]
This is well understood.

[quote]Using evolution, it is difficult to push back our understanding
beyond this ancestor, but it cannot have appeared at a stroke.
[/quote]
Certainly it could not have appeared at a stroke! Therefore, evolution
must have been in operation long before this complex common ancestor.
Something much simpler "appeared at a stroke" and then evolved
to the LCA. An evolving "RNA world" is a cliche today, and I suspect
that there may have been other evolving entities before there were RNA
sequences.

What I don>t understand is your assertion that it is difficult to push
back our understanding beyond the LCA, *using evolution*. It is certainly
true that it is impossible to push back our understanding using phylogenic
inference. But an understanding of the processes of evolution must
certainly be useful in pushing our understanding back - after all, it
is evolution that provides the dynamics leading from the "stroke" to the
LCA. Every trait of the LCA must be examined to see whether it could
plausibly have evolved, or whether it must have been primitive.

But perhaps I am overreacting here. I use the phrase OOL to refer to the
entire process - the "stroke" plus the evolution to the LCA. I prefer
this usage, because it is far from clear that the first evolving entities
were "alive". If you understand the phrase "origin of life" to refer only
to events leading to the "stroke", then I am simply quibbling about your
language. I have no wish to do that.

Thank you very much for your other recommendations.

Jim

TomHendricks474 · Guest

<< Natural selection is relevant to practically every aspect of life -
*except* its origin. >>

Then there is no such thing as 'chemical selection'?

Jim Menegay · Guest

"John Edser" <edser@ozemail.com.au> wrote in message news:<brj3n4$277c$1@darwin.ediacara.org>...
[quote]Jim Menegay wrote:-

JM:-
Can anyone recommend a good graduate or advanced undergraduate textbook
on the THEORY of evolution?

JE:-
Jim, I wish I could. None of them I have read deal with
absolute Darwinian fitness. All of them that I have read
take the Post Modern epistemological line: everything is
relative. Here relative fitnesses are only compared to other
relative fitnesses. A relative fitness must be compared to an
absolute fitness assumption and NOT to just an endless stream
of relative fitness assumptions.
[/quote]
John, you have just highlighted the reason why I need a textbook.
I have only recently learned that a "relative fitness" is simply
an "absolute fitness" divided by another (more-or-less arbitrary)
standard absolute fitness. So, it makes sense to me that one would
want to compare relative fitnesses with each other. Compare apples
to apples. But I have no idea what is meant by comparing a
relative fitness to an "absolute fitness assumption". Compare a
number to an assumption? I am completely handicapped here because
I don>t yet know the jargon.

[quote]
JM:-
I am not allergic to math. I would like to see some kind of treatment
of evolution at different levels; even if the conclusion turns out to
be that only one level (gene, organism, whatever) is important, I would
like to see this proved, rather than merely asserted.

JE:-
The proof is not difficult. Selection can only maximise
the 1st fitness level that is independent. This
is just the 1st additive fitness level.
[/quote]
"1st additive fitness level". More incomprehensible jargon for me
at this stage. Though the term is defined somewhat in context below.
The picture I have at this point is that there are various proposed
"fitness levels" (I>m guessing this includes gene-level, organism-level,
deme-level, species-level, etc.). Some of these levels are "additive"
but others are not, but I am clueless as to what the difference is and
why "additive" is a good name for the distinguishing characteristic.
And finally, among the additive levels, one of them is first (in a
bottom-to-top or top-to-bottom order?)
[quote]
A basic of evolutionary theory is the absolute difference
between dependent and independent fitnesses. If you have
3 levels: A,B,C such that A is fitness dependent on B
but B is fitness independent to C, then B can only be
selected when B is maximised.
[/quote]
"dependent" and "independent" are simply more jargon for me at this point.

[quote]Asserting that selection
at A can produce fitness altruism at B is absurd because
A is fitness dependent on B!
[/quote]
OK, you have switched from a general proof here to an application to
Hamilton>s altruism theory. But I am having trouble figuring out
which (A or B) is gene level and which is organism level. My
understanding was that both the selection and the altruism take place
at the organism level. Or, are you talking about some more exotic
application of Hamilton>s theory - to a segregation distorter or something?

[quote]Hamilton>s view that selection
at the gene level can force organism fitness altruism, a
view that entirely dominates Neo Darwinism, even today,
is absolutely wrong because all genomic gene fitnesses are
organism fitness dependent. Hamilton>s rule only compares
relative fitness counts. If gene fitnesses are dependent
on organism fitnesses then inclusive fitness can only describe
when a gene relatively increases. However that gene must become
absolutely reduced in fitness when it forces organism fitness
altruism, as Hamilton suggested it does.
[/quote]
OK, your use of "must" here suggests that you are deriving this
case from the more general theorem you were sketching above. I think
I understand that an altruistic organism is less fit (in Darwin>s sense)
than a similar egoist. And, (I>m guessing here) you are suggesting
that this must mean that the gene copy within the organism is also less
fit - it leaves fewer copies in organisms descended from the altruist. I
don>t need a general theorem to see this, it is fairly obvious. But I
don>t think that that disproves Hamilton, because there is another
organism - the one that received "b" - that is made more fit as a result
of the altruistic action. There is a probability "r" that it contains
a copy of the altruism-causing gene. So, the "clone" of identical gene copies
may well prosper, even though one of them leaves fewer progeny than it
might have.

[quote]The simple fact is
that rb>c does not exclude the possibility that the
kin selected gene will be reduced to extinction because
it is organism fitness dependent.
[/quote]
Ok, this part interests me, a lot! The gene may prosper in a relative
sense, but that is not necessarily prosperity in an absolute sense.
You are suggesting that the gene increases its own frequency in the
species of organisms, but it drives the species to extinction. I notice
that you have apparently gotten some members of the "neo-Darwinist
establishment" to admit that this is at least a theoretical possibility.

Three questions:

1. Do you believe that it is more than just a possibility - that it is
an inevitability (assuming Hamilton were correct) whenever a gene
satisfies rb>c and causes organism-level altruism?

2. I have had difficulty constructing a model in which it would take
place under any circumstances - I don>t dispute the possibility yet,
but I would like to see an example that makes it clear-cut. Are you
familiar with any such model or example? The reason this seems impossible
to me is that b must be greater than c - otherwise how could you have
rb > c? Hence, the benefit of the action to the species must be greater
than the cost to the species. What am I missing here?

3. I may be misquoting you, but on another thread you said something
to the effect that any theory predicting such a phenomenon is "insane".
I just don>t see the absurdity that you see. If such suicidally altruistic
genes arise rarely, I don>t see any logical or empirical flaws in a
theory that claims that these genes will succeed in their suicidal
enterprise and take an innocent species with them. That strikes me as
no more absurd than the fear that the AIDS virus will relatively-prosper
itself into its own extinction, taking our species with it. So, am I
misquoting you?

[quote]Hamilton left out a
term for absolute fitness within his rule, making it
just an arbitrary rule.
[/quote]
I don>t see that there is anything wrong with a rule that is capable
of predicting a relative increase in the frequency of a gene, and which
makes different predictions than the Darwinian theory. It may be false,
but that is for experiment to decide.

I don>t see why you need this rule to also make predictions about absolute
population changes. If you want that much information, go to a complete
evolution theory that covers the organism>s complete genome. But, if you
are satisfied with relative predictions for genes causing effects involving,
not just the acting organism, but also organisms that get acted upon, then
Hamilton>s rule provides a simple calculation yielding relative fitnesses.
Or am I missing something here?

[quote]Apparently for people like BOH
who reject Popper and are Post Modern in their thinking,
it is OK to suggest that just a relative gain remains an
gain, even when it becomes an absolute loss!
[/quote]
It is still unclear to me whether your objection to Hamilton is that
his theory makes incorrect predictions (in which case, I would think
that Popper would have no complaint) or whether you believe that it makes
no new predictions at all - perhaps fewer predictions than the theory it
has supplanted (in which case even people who have not read Popper, but
hate math, would avoid it.) Surely, your objection is not that it
allows the possibility of an absolute loss. Why the hell not have an
absolute loss, unless there is some metaphysical objection (benevolent
nature?) to that?

[quote]Enron
accountants suggested exactly the same nonsense.
This is what current Neo Darwinism is reduced
to, via Post Modernism.

The relationship between AB and C is independent so that
they can only form a fitness association if the single
independent unit of fitness AB, and the other independent
unit of fitness C, produce mutual but not necessarily equal,
fitness gains via this association. Allowing ABC as one unit of
selection is what is known as classical group selection.
Originally organism fitness altruism was thought to be able to
be selected for by using it. A simple inspection of the logic
proves that it cannot. Both AB and C are _independent_ so
if fitness altruism is forced for say AB, then C units
have to compete for diminishing numbers of AB units
to pillage and AB units are also selected to fight back.
[/quote]
Ok, I think I recognize this as the standard argument against group
selection, though I haven>t followed it completely. But, I
wonder whether this theoretical structure isn>t misapplied when
it is used to argue against gene-level views of evolution.
Species contain demes, which contain organisms. But organisms
don>t really contain genes in quite the same way. They contain
(or don>t contain) copies from a gene-clone. It is the gene-clone
which prospers or not - not the physical gene copy contained in an
organism. The gene clone is spread among many organisms.

[quote]The cost of this war is more than it is worth to both
sides. Van Vallen>s view that nature is just ongoing warfare
is entirely wrong. Nature is all about reducing costs
and increasing fitness gains for independent units of
selection via fitness mutualisation. We mimic this logic
with trade. What the Neo Darwinist call "reciprocal altruism"
is actually fitness mutualisation where organism fitness
altruism is _entirely_ excluded.
[/quote]
I agree that "reciprocal altruism" is a poor choice of names for
true trading relationships - for example, some of the "port/antiport"
interactions between eukariote cells and their organelles. But in
cases in which there is no specific quid-pro-quo, in which the
backs get scratched on different days, I don>t think that the name
is too bad.

[quote]The problem is, Neo
Darwinism today, is run by the political left whose
mantra is "altruism". Previously it was run by the
political right: "might is right".

Both are entirely
wrong. Science dies when basic epistemology is altered
to enhance a political bias.
[/quote]
John, I couldn>t agree more. Political opinion and political
analysis of motivations have no place in scientific discourse.
The same goes, of course, for appeals to authority and ad-hominem
attacks. Such things are pure distractions when we should be
discussing science or epistemology. The tragic thing is that
these kinds of tactics are completely counterproductive. People
who indulge in them are simply putting barriers in the way of
having their own ideas understood. It is sad.

Regards,

Jim

Jim Menegay · Guest

Tim Tyler <tim@tt1lock.org> wrote in message news:<brkrju$2o1q$1@darwin.ediacara.org>...
[quote]Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:

My primary interest is applying natural selection to origin of life, but
it is not obvious just which ideas may be useful here, so I guess I need
to know a little about everything.

I would suggest considering life as being *defined* in terms of being
an evolving system.

If you have no living system, there>s no evolution.

From this point of view, natural selection can only apply *after*
the origin of life - and thus can>t really be used to explain it.

Natural selection is relevant to practically every aspect of life -
*except* its origin.
[/quote]
Thanks for the textbook recommendations. Regarding LIFE:
I think I will assume my "Perplexed" personna in responding to you,
but also see my response to Malcolm ;-)

Dear Mr. Tyler,

My younger son shares your view of the meaning of life. All he wants
out of life is sex, (with variation, to be sure). I believe that this
misses something important. He must, IMO, go out and get a job and learn
how to maintain himself in some way. His current bountiful environment
will not last forever. My friends Varella and Maturana agree with me.

Perplexed in Peoria.

Tim Tyler · Guest

TomHendricks474 <tomhendricks474@cs.com> wrote or quoted me as saying:

[quote]Natural selection is relevant to practically every aspect of life -
*except* its origin.

Then there is no such thing as 'chemical selection'?
[/quote]
"Chemical selection" appears to be a pretty useless term.

It seems to refer to a lot of nonsense about chemicals groping
towards life without having any system of inheritance.

Either there>s a system of inheritance - (in which case the thing
is alive - and "chemicals" seems a bit disparaging, since the
evolution is biological in nature) - or there isn>t - in which case,
selection has no heritable variation to work on.

Some of the autocatalytic set folk use the term in what I suppose
is a borderline-acceptable manner - to refer to simple organisms
before any advanced biological molecules or a template
replication system existed. They use it to refer to living,
evolving organisms - *after* life>s origin.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

Tim Tyler · Guest

Jim Menegay <jamenegay@ra.rockwell.com> wrote or quoted:

[Evolution - not very relevant to life>s origin?]

[quote]I think I will assume my "Perplexed" personna in responding to you,
but also see my response to Malcolm ;-)
[/quote]
Malcom is defending this thesis:

``Using evolution, it is difficult to push back our understanding
beyond this ancestor, but it cannot have appeared at a stroke.''

....which is debatable.

It may be *difficult* to look beyond the LCA - but there are two
possibilities for reconstruction:

* Fossils;
* Scars and hangovers;

The first may be a bit far out - but the second has its uses.

Your "Perplexed" personna causes me some amusement. However,
on usenet, there often is enough confusion, without deliberately
adding more.

In this case the Peorian resident seems to have gone off on
quite a tangent - and I see little point in pursuing them.

What does evolution tell us about the origin of life?

It tells us that there must have been a path from the first
organisms to us.

I think the historical details of the early part of that path
have been pretty effectively obscured by the passage of time -
and *possible* paths between practically *any* early organism
and us are possible to imagine - so that this clue does not
amount to a hill of beans.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

Jim Menegay · Guest

tomhendricks474@cs.com (TomHendricks474) wrote in message news:<brm678$4h6$1@darwin.ediacara.org>...
[quote]Natural selection is relevant to practically every aspect of life -
*except* its origin.

Then there is no such thing as 'chemical selection'?
[/quote]
"Chemical selection" means different things to different people, but I
would say that, the way you use the term, "chemical selection" is not
just another form of "natural selection".

Darwin>s Natural Selection = Spencer + Malthus applied to Biology.

Hendrick>s Chemical Selection = Spencer + Horney applied to pre-biotic
Chemistry.

I, personally, doubt that you can get the idea to work, but if you do ...
then I would say that your theory stands beside Darwin>s, not on the
shoulders of Darwin>s.

Other people mean different things by "chemical selection", but if they
are talking about chemicals being selected, then Darwin can not be blamed
for their ideas either ;-)

TomHendricks474 · Guest

<< > Then there is no such thing as 'chemical selection'?

"Chemical selection" appears to be a pretty useless term.

It seems to refer to a lot of nonsense about chemicals groping
towards life thout having any system of inheritance.

TH
Not in a heat cycle. That would be the reason for life as that
Z which survives and has novel ways of surviving the heat.

Either there>s a system of inheritance - (in which case the thing
is alive - and "chemicals" seems a bit disparaging, since the
evolution is biological in nature) - or there isn>t - in which case,
selection has no heritable variation to work on.

Some of the autocatalytic set folk use the term in what I suppose
is a borderline-acceptable manner - to refer to simple organisms
before any advanced biological molecules or a template
replication system existed. They use it to refer to living,
evolving organisms - *after* life>s origin.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

[quote]
[/quote]
TH
Well this presents real problems because I>ve found a catch 22 that obscures
discovery - its this

This pre life period does not have replication. Without replication there is no
life - so we can>t talk about it because it is not life.

Yet I say - make up your own term if you like - but something happened in this
grey zone and it wasn>t a pop up from nothing to replicating life in an instant
(that smacks of creationism)

Specifically - if you had a heat cycle with a high heat end that denatured only
AU nucleotide bonds with 2 h-bonds, but not GC nucelotide bonds with 3 h-bonds
(as heat does) and you can>t use the term 'chemical evolution' then what kind
of selection or process is going on?

We have to have some kind of term .This idea that we can>t talk about it
because its not good enough to label selection is a bit silly .

TomHendricks474 · Guest

<< It tells us that there must have been a path from the first
organisms to us.

I think the historical details of the early part of that path
have been pretty effectively obscured by the passage of time -
and *possible* paths between practically *any* early organism
and us are possible to imagine - so that this clue does not
amount to a hill of beans.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.
[quote]
[/quote]

I don>t agree. If you recreate the same chemistry under the same conditions the
same results should happen. Now time is a factor but the origin of life is
something that - unlike a bear or a worm or a fungi - you can recreate with the
proper non live chemicals.
There are closed books and their are obscure books - this is the latter IMO.


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