Predictions of the theory of natural selection?
david ford
2) Are there any conceivable states of affairs that would disprove the
theory of natural selection?
If "yes," what conceivable states of affairs?
Regarding 2), these conceivable states of affairs would disprove the
theory of natural selection:
biology did not exist
the universe did not exist
time did not exist
the dimensions of length, width, and height did not exist
matter did not exist
the universe was not about 15 billion years old,
but instead was 15 days old
living organisms do not reproduce
living organisms do not pass their characteristics on
to their offspring
organisms reproduce but the offspring are 100.000...% identical
to the parents
Woden
news:b1c67abe.04011...@posting.google.com:
> 1) What are some predictions of the theory of natural selection?
Why ask us? Why don't you do some serious study of modern biological
sciences? But then again, you might have to learn something.
>
> 2) Are there any conceivable states of affairs that would disprove the
> theory of natural selection?
> If "yes," what conceivable states of affairs?
Lots of things could disprove this theory. After all, that's the nature
of scientific theories. Let us know when someone finds some real and
valid evidence that disproves this theory.
>
>
> Regarding 2), these conceivable states of affairs would disprove the
> theory of natural selection:
> biology did not exist
> the universe did not exist
> time did not exist
> the dimensions of length, width, and height did not exist
> matter did not exist
> the universe was not about 15 billion years old,
> but instead was 15 days old
> living organisms do not reproduce
> living organisms do not pass their characteristics on
> to their offspring
> organisms reproduce but the offspring are 100.000...% identical
> to the parents
And how many of these have been observed?
--
Woden
"religion is a socio-political institution for the control of
people's thoughts, lives, and actions; based on
ancient myths and superstitions perpetrated through
generations of subtle yet pervasive brainwashing."
Ron Baker, Pluralitas!
"david ford" <dfo...@gl.umbc.edu> wrote in message
news:b1c67abe.04011...@posting.google.com...
> 1) What are some predictions of the theory of natural selection?
One prediction is that after billions of years
a "david ford" would arise that would ask vague
hypothetical questions about evolution, people
would actually try to answer, and david ford would
never respond.
--
Dr. Ron Baker, Ath.D.
John Wilkins
And insist on you getting a book from the library, and then never ask
the questions, until the book had to be returned to the library...
--
John Wilkins
"And this is a damnable doctrine" - Charles Darwin, Autobiography
gen2rev
ford) wrote in <b1c67abe.04011...@posting.google.com>:
> 1) What are some predictions of the theory of natural selection?
As I pointed out in news:i2pstvk554fvlskpu...@4ax.com,
some species will become extinct, and species will tend to diversify.
> 2) Are there any conceivable states of affairs that would disprove the
> theory of natural selection?
Yes.
> If "yes," what conceivable states of affairs?
The state of affairs where any possible change in the environment had no
effect on reproductive success.
The state of affairs where no species ever became extinct.
And the state of affairs where the fossil record was uniform, that is,
any reasonably large fossil sample was the same as any other sample. In
fact, it could be argued that this is what we would expect if flood
geology is true. But alas, we don't see that state of affairs...
> Regarding 2), these conceivable states of affairs would disprove the
> theory of natural selection:
> biology did not exist
> the universe did not exist
> time did not exist
> the dimensions of length, width, and height did not exist
> matter did not exist
In all of the above scenarios there would be no biology, hence these
"states of affairs" are non sequitur.
> the universe was not about 15 billion years old,
> but instead was 15 days old
Not a problem for natural selection.
> living organisms do not reproduce
> living organisms do not pass their characteristics on
> to their offspring
These two are also non sequitur. These situations are like testing to
see if electrical appliances work without actually plugging them in.
> organisms reproduce but the offspring are 100.000...% identical
> to the parents
Not a problem for natural selection, as there is at least one species
like this. However, such a species would be very sensitive to
environmental changes.
Nathan Baum
What's the matter? Didn't like the answers you got last time?
Bobby D. Bryant
> the dimensions of length, width, and height did not exist
Don't know about natural selection, but that would be an absolute disaster
for Arkology!
--
Bobby Bryant
Austin, Texas
Steven J.
>
> 2) Are there any conceivable states of affairs that would disprove the
> theory of natural selection?
> If "yes," what conceivable states of affairs?
>
that this is the case) no variations in any population (or most populations)
increase or decrease an organism's chances of leaving descendants would
suffice. Any demonstration that there is no way for beneficial new
variations to arise (no beneficial mutations) would suffice. For that
matter, demonstrating that variations have potentially huge effects on
"fitness," but that none of these variations could be inherited, would
suffice. It would not be necessary to show that living things do not pass
on traits to their offspring, or that the offspring are identical to each
other or to the parents, but simply to show that differences among the
offspring do not come from inheritance (that is, hereditability of variation
is zero).
For your purposes (not so much falsifying "natural selection," as falsifying
the idea that it could account for common ancestry of, say, alligators and
hummingbirds), showing that "kinds" exist would suffice. Charles Darwin
spoke of falsifying his theory by showing that any structure or organ
existed that could not be produced by numerous minor modifications of
precursor structures in a living thing. If regions in "genetic space"
coding for organisms that are viable in some plausible environment were
widely separated (so that there were no traversible evolutionary paths
between "kinds"), this would suffice to falsify natural selection, but would
be difficult. I recall Chuck Colson arguing, e.g. that fish could not
evolve into terrestrial animals, because fish with lungs would drown; he
apparently had not heard of lungfish. Nonobvious but perfectly possible
intermediate states are not only possible in theory, but often demonstrable
in fact.
>
> Regarding 2), these conceivable states of affairs would disprove the
> theory of natural selection:
> biology did not exist
> the universe did not exist
> time did not exist
> the dimensions of length, width, and height did not exist
> matter did not exist
> the universe was not about 15 billion years old,
> but instead was 15 days old
>
All of this would leave natural selection with nothing to explain. It seems
odd to speak of a "false" explanation for nonexistent phenomena.
>
> living organisms do not reproduce
> living organisms do not pass their characteristics on
> to their offspring
> organisms reproduce but the offspring are 100.000...% identical
> to the parents
>
-- Steven J.
Jeremy Price
news:b1c67abe.04011...@posting.google.com...
lots of these would be worse for existing than for evolution...
mel turner
dfo...@gl.umbc.edu [david ford] wrote...
>1) What are some predictions of the theory of natural selection?
That adaptive changes in organismal features arise during the course
of evolution? That features arise by gradual modifications of existing
features. Etc.
>2) Are there any conceivable states of affairs that would disprove the
>theory of natural selection?
Many. And there are others that would disprove any evolutionary
explanation, not just evolution by natural selection.
>If "yes," what conceivable states of affairs?
See below for some hypotheticals more refuting of evolution in
general than natural selection.
Somehow showing that no differences in heritable traits can
ever affect an organism's relative reproductive success would be
a finding specifically refuting natural selection.
You might perhaps show that strong artifical selection on
experimental populations of organisms never has any effect
on the frequency of alleles or phenotypic traits in the
population. Maybe show there are some hidden mechanisms that
prevent all population-level genetic changes.
>Regarding 2), these conceivable states of affairs would disprove the
>theory of natural selection:
>biology did not exist
>the universe did not exist
>time did not exist
>the dimensions of length, width, and height did not exist
>matter did not exist
Those are pretty silly hypothetical conditions for this discussion,
but sure, any theory of evolution is going to require the existence
of things able to evolve.
>the universe was not about 15 billion years old,
No. If life as we know it existed, it will have been subject to
evolution by natural selection for however long it has existed.
> but instead was 15 days old
If the world was very young, there wouldn't be time for much evolution
to occur. Still, even as little as 15 days might allow several
generations of bacteria, etc. to evolve. Still, if the world was as
young as YECs claim, most organisms wouldn't have had much time to
evolve significantly.
>living organisms do not reproduce
Of course. That would prevent all evolution, not just selection.
>living organisms do not pass their characteristics on
> to their offspring
Of course. But isn't that really the same as the preceding? Or
are you proposing that organisms would have offspring with
absolutely no characteristics in common with their parents?
>organisms reproduce but the offspring are 100.000...% identical
> to the parents
Good for you. You've hit on a major one that's from my earlier lists
of hypotheticals. If heritable mutations or other sources of genetic
variations were nonexistent, then not only evolution by natural
selection, but evolution in general would be impossible.
[modified from an earlier post]
There have been many past posts suggesting hypothethical findings that
would refute hypotheses of common descent; here are some of mine:
[probably a tad repetitious]
http://groups.google.com/groups?selm=7eprga%24rr6%241%40news.duke.edu
http://groups.google.com/groups?selm=6msvaf%24o5d%241%40news.duke.edu
http://groups.google.com/groups?selm=9a2af7%24oe3%241%40news.duke.edu
http://groups.google.com/groups?selm=8s8m7h%248m2%241%40news.duke.edu
http://groups.google.com/groups?selm=8ha6sd%24pnm%242%40news.duke.edu
http://groups.google.com/groups?selm=7lak5o%24gf0%241%40news.duke.edu
http://groups.google.com/groups?selm=7l524k%24hlv%241%40news.duke.edu
http://groups.google.com/groups?selm=7iahbi%241ni%241%40news.duke.edu
http://groups.google.com/groups?selm=8ejat0%24q21%241%40news.duke.edu
http://groups.google.com/groups?selm=7eprga%24rr6%241%40news.duke.edu
Anyway, the theory is unfalsified, but it's not at all unfalsifiable
in principle. It's just that none of the falsifying situations apply
to the real world.
cheers
caerbannog
These are just the kind of questions that someone who
majored in history and philosophy, has no training in
science, and has too much free time on his hands,
might ask.....
PeteM
>
>"david ford" <dfo...@gl.umbc.edu> wrote in message
>news:b1c67abe.04011...@posting.google.com...
>> 1) What are some predictions of the theory of natural selection?
>>
>> 2) Are there any conceivable states of affairs that would disprove the
>> theory of natural selection?
>> If "yes," what conceivable states of affairs?
>>
>Any demonstration that (and some creationists on this newsgroup have argued
>that this is the case) no variations in any population (or most populations)
>increase or decrease an organism's chances of leaving descendants would
>suffice. Any demonstration that there is no way for beneficial new
>variations to arise (no beneficial mutations) would suffice. For that
>matter, demonstrating that variations have potentially huge effects on
>"fitness," but that none of these variations could be inherited, would
>suffice. It would not be necessary to show that living things do not pass
>on traits to their offspring, or that the offspring are identical to each
>other or to the parents, but simply to show that differences among the
>offspring do not come from inheritance (that is, hereditability of variation
>is zero).
But these examples require a demonstration that certain things or events
do not exist or cannot occur or have never occurred. They are therefore
not practical ways of falsifying natural selection, since (as skeptics
are always saying) you can't prove a negative.
>
>For your purposes (not so much falsifying "natural selection," as falsifying
>the idea that it could account for common ancestry of, say, alligators and
>hummingbirds),
Falsifying a theory is not at all the same as falsifying the idea that
it could account for observed phenomena.
>showing that "kinds" exist would suffice. Charles Darwin
>spoke of falsifying his theory by showing that any structure or organ
>existed that could not be produced by numerous minor modifications of
>precursor structures in a living thing.
Again, it would be logically impossible to disprove evolution that way,
because it is always open to an evolutionist to say, "Sure, we don't yet
know how such-and-such an organ evolved by minor modifications of
simpler structures ... but on the other hand you can't show that it
couldn't have done. Just wait and we'll work it out."
--
PeteM
Al Klein
<gen...@crosswinds.net> posted in alt.atheism:
>On Sat, 17 Jan 2004 01:29:52 +0000 (UTC), dfo...@gl.umbc.edu (david
>ford) wrote in <b1c67abe.04011...@posting.google.com>:
>> organisms reproduce but the offspring are 100.000...% identical
>> to the parents
>Not a problem for natural selection, as there is at least one species
>like this.
Barring mutation there are millions (at least) of species like this.
--
"If knowledge can create problems, it is not through ignorance that we can
solve them."
-Isaac Asimov
(random sig, produced by SigChanger)
rukbat at optonline dot net
Mark Isaak
>1) What are some predictions of the theory of natural selection?
You tell us. I want to see if it is possible for you to learn
anything. At the moment, evidence points to "no".
--
Mark Isaak eciton (at) earthlink (dot) net
"Voice or no voice, the people can always be brought to the bidding of
the leaders. That is easy. All you have to do is tell them they are
being attacked, and denounce the pacifists for lack of patriotism and
exposing the country to danger." -- Hermann Goering
Steven J.
"PeteM" <m...@privacy.net> wrote in message
news:S9IgOQBX...@privacy.net...
negative? You would be showing that a given phenomenon does not occur, or
does not account for the phenomena which are attributed to it. Would not,
in point of fact, falsifying *anything* be "proving a negative?" Still,
would not the inability to find any cases where inhertible variation
affected one's chances of leaving offspring very severely weaken the theory
of natural selection, even if it did not falsify it?
In fact, a well-established thesis in the philosophy of science is that
"naive falsificationism" is mistaken, and that no hypothesis can be simply
and directly disproved by any single observation. Absolute disproof is as
impossible to science as absolute proof is. Any observation contrary to a
hypothesis might be explained by the falsity of the hypothesis, but it might
also be a bad observation, or a mistake about the other factors and causes
at work, or the intervention of some unknown cause beyond those we thought
we were studying.
>
> >For your purposes (not so much falsifying "natural selection," as
falsifying
> >the idea that it could account for common ancestry of, say, alligators
and
> >hummingbirds),
>
> Falsifying a theory is not at all the same as falsifying the idea that
> it could account for observed phenomena.
>
Accounting for observed phenomena is what theories are *for*. Showing that
the causes proposed by a theory actually exists, but can't produce the
effects the theory atttributes to it, would falsify the theory (to the
extent that any theory can be falsified. And since many creationists do
indeed allow that natural selection occurs, but don't think it can explain
complex adaptions, I thought it important to address what I thought was
likely to be Ford's actual point.
>
> >showing that "kinds" exist would suffice. Charles Darwin
> >spoke of falsifying his theory by showing that any structure or organ
> >existed that could not be produced by numerous minor modifications of
> >precursor structures in a living thing.
>
> Again, it would be logically impossible to disprove evolution that way,
> because it is always open to an evolutionist to say, "Sure, we don't yet
> know how such-and-such an organ evolved by minor modifications of
> simpler structures ... but on the other hand you can't show that it
> couldn't have done. Just wait and we'll work it out."
>
I noted that this would be a quite difficult mode of falsification. Oddly,
Michael Behe does not seem to have grasped your point; he seems to think
that easily detectable sorts of structures could show that natural selection
did not produce them. For that matter, any number of less erudite
creationists have offered arguments along the lines of "what good is half an
eye/wing/heart," which are attempts to show that precisely such
falsifications exist. Note that in many such cases, function intermediates
can be found in the world today.
>
> --
> PeteM
>
-- Steven J.
david ford
> > 1) What are some predictions of the theory of natural selection?
>
> One prediction is that after billions of years
> a "david ford" would arise that would ask vague
> hypothetical questions about evolution, people
> would actually try to answer, and david ford would
> never respond.
What else does the theory of natural selection predict?
david ford
Lamarck proposed a theory of how animals and plants acquired new
structures having new functions (that proposal hereinafter termed
"Lamarck's theory"). Lamarck's theory involved organisms inheriting
characteristics that their parents acquired from interaction with the
surrounding environment.
1) What are some predictions of Lamarck's theory?
2) Are there any conceivable states of affairs that would disprove
Lamarck's theory?
If "yes," what conceivable states of affairs?
Regarding 2), these conceivable states of affairs would disprove
Lamarck's theory:
david ford
david ford wrote:
> > 1) What are some predictions of the theory of natural selection?
> >
> > 2) Are there any conceivable states of affairs that would disprove the
> > theory of natural selection?
> > If "yes," what conceivable states of affairs?
> >
> >
> > Regarding 2), these conceivable states of affairs would disprove the
> > theory of natural selection:
>
> These are just the kind of questions that someone who
> majored in history and philosophy, has no training in
> science, and has too much free time on his hands,
> might ask.....
It sounds like you might have read at least the top portion of one of
my essays. Is it the case that you read such a portion? If "yes,"
did you read the essay? If "yes," what did you think of the essay?
John Wilkins
> Predictions of the theory of Lamarck?
>
> Lamarck proposed a theory of how animals and plants acquired new
> structures having new functions (that proposal hereinafter termed
> "Lamarck's theory"). Lamarck's theory involved organisms inheriting
> characteristics that their parents acquired from interaction with the
> surrounding environment.
This is not Lamarck's theory - it was the widely held consensus right up
until the 1890s, and even later. Darwin held it. Galton was the first to
challenge it in public scientific discourse - Mendel's work was almost
hidden from sight.
>
> 1) What are some predictions of Lamarck's theory?
>
> 2) Are there any conceivable states of affairs that would disprove
> Lamarck's theory?
> If "yes," what conceivable states of affairs?
Those observed - hereditable characters involving nuclear genes and
mitochondrial genes do not get amended on the basis of the life
experience of the parental organism. All "cases" of Lamarckian-style
evolution turn out to be either:
1. Baldwin effect (fully Darwinian)
2. Weismannian heredity (sequestered germline)
3. Horizontal transfer of Darwinianly-acquired genes
4. Somatic cell inheritance or biochemical transfer, usually not lasting
longer than a couple of generations
5. Maternal imprinting (depending on the species gestatory processes)
or just perhaps
6. Immunological insertion of somatically selected immunological genes
via retroinsertion from immune cells to germline (Ted Steele's
"Lamarckism", which is not Lamarckian and which is not yet proven).
>
>
> Regarding 2), these conceivable states of affairs would disprove
> Lamarck's theory:
> biology did not exist
Trivially true
> the universe did not exist
Ditto
> time did not exist
Ditto
> the dimensions of length, width, and height did not exist
> matter did not exist
Ditto
> the universe was not about 15 billion years old, but instead was 15
> days old
False - Lamarckian inheritance could occur for any organism that had
less than the time alloted as a generation time. And anyway, this is
trivially true.
> living organisms do not reproduce
Trivially true, of any biological theory.
> living organisms do not pass their characteristics on to their
> offspring
Ditto
> organisms reproduce but the offspring are 100.000...% identical to the
> parents
Ditto.
What do you hope to achieve with these non sequiturs, apart from
demonstrating your ignorance of both the h istory of biology and the
biology itself?
John Wilkins
Glad you asked, david. I have this book out from the library right now -
perhaps you have heard of it:
Bell, G. (1997). Selection: The mechanism of evolution. New York,
Chapman and Hall.
He lists 175 principles of natural selection, each of which are
illustrated with examples in the primary literature. As selection is a
stochastic process and highly sensitive to the initial and boundary
conditions of each case, not to mention the fact that mutation occurs
unrelatedley to the selective necessities of a population (p33), these
principles are likely but not mandatory (as with any stochastic model),
but they are models and those models do predict.
Perhaps you have read it?
By the way, you never responded to my last two replies to your material.
Are you still digesting them, or have you forgotten?
Cheetah
> 2) Are there any conceivable states of affairs that would disprove the
> theory of natural selection?
> If "yes," what conceivable states of affairs?
If any complex animal were discovered that did not use DNA, and did not have
the same set of familar organs - heart etc - and instead used a totally
different biology, then it would be very difficult to explain.
However, all animals on earth use the same basic chemistry. If some deity
created all animals from scratch there is no reason to suppose they would
have anything in common, however if evolution is true it would mean we
would see a line of progression.
The fact is that all animals can fit within a hiracy - and while sometimes
the exact position is uncertain the fact that all animals belong in the
chain somewhere is clear. If only one animal didn't fit we would have to
reevaluate everything.
Nathan Baum
> david ford wrote:
>
>> 2) Are there any conceivable states of affairs that would disprove the
>> theory of natural selection?
>> If "yes," what conceivable states of affairs?
>
> If any complex animal were discovered that did not use DNA, and did not
> have the same set of familar organs - heart etc - and instead used a
> totally different biology, then it would be very difficult to explain.
It would be easy to explain: the animal did not evolve from the same common
ancestor as the animals we have seen so far.
Al Klein
<sjt195...@nts.link.net.INVALID> posted in alt.atheism:
>"PeteM" <m...@privacy.net> wrote in message
>news:S9IgOQBX...@privacy.net...
>> But these examples require a demonstration that certain things or events
>> do not exist or cannot occur or have never occurred. They are therefore
>> not practical ways of falsifying natural selection, since (as skeptics
>> are always saying) you can't prove a negative.
>Would not "falsifying natural selection," itself, amount to proving a
>negative?
"You cannot prove a negative" is a misstatement. You can not prove an
unlimited existential negative.
>You would be showing that a given phenomenon does not occur, or
>does not account for the phenomena which are attributed to it.
Nothing existential.
>Would not, in point of fact, falsifying *anything* be "proving a negative?"
Irrelevant.
>Still, would not the inability to find any cases where inhertible variation
>affected one's chances of leaving offspring very severely weaken the theory
>of natural selection, even if it did not falsify it?
Yes, but since cases have been found, the question is moot.
>In fact, a well-established thesis in the philosophy of science is that
>"naive falsificationism" is mistaken, and that no hypothesis can be simply
>and directly disproved by any single observation.
An observation that directly contradicts a necessary claim of a theory
would falsify the theory.
>Absolute disproof is as impossible to science as absolute proof is.
Falsification isn't absolute disproof.
>Any observation contrary to a
>hypothesis might be explained by the falsity of the hypothesis, but it might
>also be a bad observation
Any and all observations may be bad. One good observation can falsify
a theory.
--
"Men never do evil so completely and cheerfully as when they do it from religious
conviction."
- Blaise Pascal (1623-1662)
david ford
What are 3 predictions that Bell discusses of the theory of natural
selection?
Does Dawkins do a good job of describing the creative abilities/powers
of the mechanism described by Darwin's theory of natural selection?
Does Dawkins do a good job of describing what is involved in the
manner of operation of the Darwinian mechanism?
Do you agree with Bell that [Bell on xviii]"living complexity cannot
be explained except through [Darwinian natural] selection"?
Do you agree with Bell that Darwinian natural [Bell on xix]"selection
is the only process that _causes_ evolution"?
Do you think that in textbooks, [Bell on xix]"the neutral theory of
molecular evolution" should be [Bell]"treated on a level with-- that
is, at the same length as-- the theory of natural selection"?
Or do you agree with Bell when he says about such equal time textbook
treatment, [Bell]"This is surely unjustifiable."?
As a side note, you asked me for a definition of blindwatchmaking.
The definition appears in
concept of "blindwatchmaking"
http://tinyurl.com/2ko4m
aka
http://www.google.com/groups?selm=b1c67abe.0401101006.38dc8f17%40posting.google.com
AC
Cheetah <mrs...@nothingbutnet.co.nz> wrote:
> david ford wrote:
>
>> 2) Are there any conceivable states of affairs that would disprove the
>> theory of natural selection?
>> If "yes," what conceivable states of affairs?
>
> If any complex animal were discovered that did not use DNA, and did not have
> the same set of familar organs - heart etc - and instead used a totally
> different biology, then it would be very difficult to explain.
No more difficult than organisms that do. It is possible that there might
be survivors of a seperate abiogenesis event, or that two groups of life
forms split off before features like RNA evolved. I'm not talking about
likelihood here.
<snip>
--
Aaron Clausen
tao_of_cow/\alberni.net (replace /\ with @)
neepy
(1) You don't know the answers, but are too dumb to use a library or
the Net to find them.
(2) You don't know the answers, but hope that someone here who doesn't
know the answers either will reply in a way that you can use to
support your crackpot ideas.
(3) You know the answers, but they scare you so much that you have to
pretend you don't, and hope someone here who doesn't know them will
reply in a way that you can use to support your crackpot ideas.
(4) You know the answers, but think that posing these questions will
suggest to others that they constitute a problem for evolutionary
theory when they don't.
DarwinsMistress
From: dfo...@gl.umbc.edu (david ford)
Date: 16/01/2004 8:29 PM Eastern Standard Time
Message-id: <b1c67abe.04011...@posting.google.com>
1) What are some predictions of the theory of natural selection?
2) Are there any conceivable states of affairs that would disprove the
theory of natural selection?
If "yes," what conceivable states of affairs?
Regarding 2), these conceivable states of affairs would disprove the
theory of natural selection:
biology did not exist
the universe did not exist
time did not exist
the dimensions of length, width, and height did not exist
matter did not exist
the universe was not about 15 billion years old,
but instead was 15 days old
living organisms do not reproduce
living organisms do not pass their characteristics on
to their offspring
organisms reproduce but the offspring are 100.000...% identical
to the parents
There are no predictions of NS. Evol doofuses always ask creationists for
testable predictions, but they have none of their own. Goddamn ignaromuses. Why
we have to live with the scourge of these dodoheads I simply do not know!
''burn the creationist heretics for exposing the lie of
evolution!''-FundieHater
Nathan Baum
Even it that were true, would the absence of testable predictions of NS
somehow mean that it was okay that creationism lacked testable predictions?
Matt Silberstein
<ruk...@pern.invalid>:
>On Sat, 17 Jan 2004 03:23:11 +0000 (UTC), gen2rev
><gen...@crosswinds.net> posted in alt.atheism:
>
>>On Sat, 17 Jan 2004 01:29:52 +0000 (UTC), dfo...@gl.umbc.edu (david
>>ford) wrote in <b1c67abe.04011...@posting.google.com>:
>>> organisms reproduce but the offspring are 100.000...% identical
>>> to the parents
>
>>Not a problem for natural selection, as there is at least one species
>>like this.
>
>Barring mutation there are millions (at least) of species like this.
Do either of you know of any species that have error free genetic
replication?
gen2rev
<matts...@ix.netcom.nospamcom> wrote in
<3rgo00t55mned9c09...@4ax.com>:
Well, I don't know about 100% error free replication, since I'm unaware
of such a high-fidelity replication mechanism, but the whiptail lizard
_Cnemidophorus uniparens_ reproduces parthenogenetically, and the young
are clones of the mother.
But I'd have to disagree with Al that barring mutation there would be
millions of species like this, since recombination of genes from the two
parents in sexually reproducing species will *always* result in
variation.
My original point (perhaps not stated strongly enough) was that there
has to be variation to test natural selection. A species that has no
variation in genotypes wouldn't be much of a test one way or the other.
Al Klein
>In talk.origins I read this message from Al Klein
><ruk...@pern.invalid>:
>
>>On Sat, 17 Jan 2004 03:23:11 +0000 (UTC), gen2rev
>><gen...@crosswinds.net> posted in alt.atheism:
>>
>>>On Sat, 17 Jan 2004 01:29:52 +0000 (UTC), dfo...@gl.umbc.edu (david
>>>ford) wrote in <b1c67abe.04011...@posting.google.com>:
>>>> organisms reproduce but the offspring are 100.000...% identical
>>>> to the parents
>>
>>>Not a problem for natural selection, as there is at least one species
>>>like this.
>>
>>Barring mutation there are millions (at least) of species like this.
>
>Do either of you know of any species that have error free genetic
>replication?
Barring error? Single-gendered species. Including error? None.
--
"I have never imputed to Nature a purpose or a goal, or anything that could be under-
stood as anthropomorphic. What I see in Nature is a magnificent structure that we can
comprehend only very imperfectly, and that must fill a thinking person with a feeling of
humility. This is a genuinely religious feeling that has nothing to do with mysticism."
- 1954 or 1955; quoted in Dukas and Hoffman _Albert Einstein the Human Side_, p. 39
Al Klein
<gen...@crosswinds.net> posted in alt.atheism:
>But I'd have to disagree with Al that barring mutation there would be
>millions of species like this, since recombination of genes from the two
>parents in sexually reproducing species will *always* result in
>variation.
But there are millions of asexual species.
--
"He who joyfully marches to music in rank and file has already earned my
contempt. He has been given a large brain by mistake, since for him, the
spinal cord would fully suffice."
- Albert Einstein
Matt Silberstein
thread Re: Predictions of the theory of natural selection?
(<00ko00dn06vgkf593...@4ax.com>):
>On Mon, 19 Jan 2004 20:53:49 +0000 (UTC), Matt Silberstein
><matts...@ix.netcom.nospamcom> wrote in
><3rgo00t55mned9c09...@4ax.com>:
>
>> In talk.origins I read this message from Al Klein
>> <ruk...@pern.invalid>:
>>
>> >On Sat, 17 Jan 2004 03:23:11 +0000 (UTC), gen2rev
>> ><gen...@crosswinds.net> posted in alt.atheism:
>> >
>> >>On Sat, 17 Jan 2004 01:29:52 +0000 (UTC), dfo...@gl.umbc.edu (david
>> >>ford) wrote in <b1c67abe.04011...@posting.google.com>:
>> >>> organisms reproduce but the offspring are 100.000...% identical
>> >>> to the parents
>> >
>> >>Not a problem for natural selection, as there is at least one species
>> >>like this.
>> >
>> >Barring mutation there are millions (at least) of species like this.
>>
>> Do either of you know of any species that have error free genetic
>> replication?
>
>Well, I don't know about 100% error free replication, since I'm unaware
>of such a high-fidelity replication mechanism, but the whiptail lizard
>_Cnemidophorus uniparens_ reproduces parthenogenetically, and the young
>are clones of the mother.
So? The DNA still replicates with errors. Cloning just makes it
non-sexual reproduction.
>But I'd have to disagree with Al that barring mutation there would be
>millions of species like this, since recombination of genes from the two
>parents in sexually reproducing species will *always* result in
>variation.
I suspect that baring mutations life would die out since species
could not adapt to new conditions.
>My original point (perhaps not stated strongly enough) was that there
>has to be variation to test natural selection. A species that has no
>variation in genotypes wouldn't be much of a test one way or the other.
Sure. Selection is always a comparison, at least how we usually
mean it.
John Wilkins
At random:
81 Selection directed towards any given character is likely to cause
changes in other characters
92. Optimal patterns of reproduction evolve as compromises.
158. Resistance and virulence are costly.
[Note: one of these discussions is, in my view, incomplete. Bet you
can't guess which one and why.]
>
> Does Dawkins do a good job of describing the creative abilities/powers
> of the mechanism described by Darwin's theory of natural selection?
Where?
>
> Does Dawkins do a good job of describing what is involved in the
> manner of operation of the Darwinian mechanism?
Where?
>
> Do you agree with Bell that [Bell on xviii]"living complexity cannot
> be explained except through [Darwinian natural] selection"?
Not quite. There are two, and only two ways in which a complex system
can come to be. One is a form or more correctly a generalised version of
induction - trial and error. Natural selection is an analogous form of
induction.
The other is by a full and complete knowledge of all variables and
constants of the system, the initial and boundary conditions, and
sufficient computational capacity to extrapolate all the states the
system can contain, in order to set up the complexity, and if bound by
physical processes, to understand exactly what dynamics will output the
complexity desired.
Now the latter case is well outside the realm of science - if God has
that knowledge and ability, science will never know it. But in the realm
in which science is competent, the only way to gather that knowledge of
a system of any complexity in a finite amount of time is by trial and
error. In short, either by physical processes that mimic trial and error
(e.g., by selection) or by cognitive processes that are a kind of
natural selection of ideas.
Bell's comment is therefore correct to a first, and indeed second and
later approximation. Only a philosopher (or a theologian) would
entertain the latter case in the situation of living beings. Note that
the quote you give aboe continues: "and does not require any other
category of explanation whatsoever". This is quite correct - nothing
besides selection is required to account for the complexity of living
beings.
>
> Do you agree with Bell that Darwinian natural [Bell on xix]"selection
> is the only process that _causes_ evolution"?
Given his prior definition, yes. However, I do not think that is a
sufficient definition of evolution. Here is the full quote, with the
relevant bit emphasised:
"A further weakness [in education of evolution at uni level] is that
when selection is described, it is often treated as one of several
possible mechanisms of evolution. In the best textbook currently
available, for example, random genetic change is treated at about the
same length as selection, and it is quite common to see the neutral
theory of molecular evolution being treated on a level with - that is,
at the same length as - the theory of natural selection. This is surely
unjustifiable. *Evolution is the development and maintenance of complex
organization that functions appropriately in given conditions. There are
many forces that hinder evolution - mutation, sampling error,
immigration, and so forth - but* selection is the only process that
_causes_ evolution."
Bell has made a definition and in the context of that definition,
selection surely *is* the only process. But that definition, and indeed
his view that these other things impede evolution, is tantamount to
saying that evolution is just adaptation, and that is both circular
(selection is the only process that causes adaptation) and wrong
(evolution is change of populations, and these other things contribute
to that).
In fact, I would say that all selection is, is bias in reproductive
sampling rates of genes due to economic success; if that is the
definition used, then drift and selection are merely different ends of
the spectrum of sampling rates.
>
> Do you think that in textbooks, [Bell on xix]"the neutral theory of
> molecular evolution" should be [Bell]"treated on a level with-- that
> is, at the same length as-- the theory of natural selection"?
> Or do you agree with Bell when he says about such equal time textbook
> treatment, [Bell]"This is surely unjustifiable."?
See above. Bell's book is, to me, useful as an extended treatment of
selection. Evolution, though, is more than selection. And this has been
known since Fisher's _Genetical Theory of Natural Selection_, if not
before.
>
> As a side note, you asked me for a definition of blindwatchmaking.
> The definition appears in
> concept of "blindwatchmaking"
> http://tinyurl.com/2ko4m
> aka
> http://www.google.com/groups?selm=b1c67abe.0401101006.38dc8f17%40posting.g
> oogle.com
Already answered. Unfortunately, due to a crash of my client software, I
have lost access to past posts. If you view that article by thread, you
should see my response. Basically, and this should be no surprise, you
are wrong.
david ford
Feel free to speculate all you want about my motivations for asking
questions.
Batch #2 of questions for John W. regarding Bell:
In the Bell book, what are two section headings that make assertions
for which [Bell on xxii]"the experimental evidence goes against the
assertion"?
For those two instances, do you agree with Bell that [Bell]"the
assertion is so likely to be true that the experimental results should
be laid aside"?
How well does the section "Very improbable structures readily arise
through the [non-intelligence-directed-at-any-level] cumulation of
small alterations" make that section heading's allegation?
Within that section, I wrote "bogus" and "totally bogus" beside the
only complete paragraph on page 23. What is your view of that
paragraph?
I am reminded of
Sean P. on Dawkins's "Methinks it is like a weasel" illustration
http://tinyurl.com/3fhxl
aka
http://www.google.com/groups?selm=b1c67abe.0401142214.3c4c92b0%40posting.google.com
How accurate-to-reality are the section headings, considering Bell's
observation on xxii that "wherever possible, I have tried to find
experiments that substantiate the assertions made by the section
heading; this has often not been possible"?
I am reminded of
1992 Orr & Coyne on Fisher
http://tinyurl.com/y86y
aka
http://www.google.com/groups?selm=Pine.SGI.3.95.970329001049.19794A-100000%40umbc10.umbc.edu
1992 _American Naturalist_ paper by Orr & Coyne
http://tinyurl.com/y86w
aka
http://www.google.com/groups?selm=Pine.SGI.3.96.980614220859.6338A-100000%40umbc8.umbc.edu
These 3 questions deal with your view of evidence of which you are
aware:
1) Is the best line of experimental evidence for the theory of natural
selection discussed in Bell's book?
2) Is the best line of theoretical evidence for the theory of natural
selection discussed in Bell's book?
3) Is the best line of observational/ out-in-the-field evidence for
the theory of natural selection discussed in Bell's book?
For "yes" responses to any of the 3 questions, where does Bell discuss
that evidence?
For "no" responses to any of the 3 questions, what is the best such
evidence?
In the Introduction, Bell states on xx that his book will "refer only
very briefly, or not at all, to many of the most familiar and
important issues of evolutionary biology." What are 4 such issues
that Bell discusses at most only briefly?
About the periodic attacks on the theory of natural selection claiming
that [Bell on xviii]"the theory is outdated, logically invalid,
overtaken by recent discoveries," etc., do you agree with Bell that
"These mosquitoes must simply be swatted as they swarm."?
Do you consider the arguments advanced by Sean P. to be mosquitoes?
About how frequently do you swat mosquitoes swarming in talk.origins?
After discussing the reasons his book doesn't approach Darwinian
natural selection via population genetics, Bell concludes on xx,
"Population genetics, as currently understood, is therefore an
inadequate foundation for a general account of selection." Do you
agree with his conclusion?
Do you agree with Bell on xx that population genetics is largely
interested in sorting out "one or a few types from some range of
pre-existing variation"?
Bell continues, "The most important consequences of [Darwinian
natural] selection, however, involve the appearance of new types over
long periods of time." Do you agree?
Where in the book does there appear discussion of [Bell]"the
appearance of new types"?
Bell states that the theory of natural selection [Bell on xvii]"is one
of the only two categories of theory competent to explain the living
world."
What are the two categories?
Compare
Bell notes design inference is "entirely reasonable"
http://tinyurl.com/yj6z
aka
http://www.google.com/groups?selm=Pine.LNX.4.44L.01.0311192117140.25662-100000%40linux2.gl.umbc.edu
Bell opines on page 1 that "The main purpose of evolutionary biology
is to provide a rational explanation for the extraordinarily complex
and intricate organization of living things." Is the proposition that
intelligence/mind was responsible [Bell]"for the extraordinarily
complex and intricate organization of living things" a rational
explanation, in your view?
If "no," upon what grounds do you make your assertion?
Final question, for now:
Do you regret suggesting that I obtain the Bell book?
When we're done with Bell, perhaps we can pick up where we left off in
the thread "Naive ?s on the Blindwatchmaker Thesis," the first post
therein being
http://tinyurl.com/3x8x5
aka
http://www.google.com/groups?selm=b1c67abe.0312242003.1777307%40posting.google.com
John Wilkins
dfo...@gl.umbc.edu (david ford) wrote:
> neepy <dsuthe...@hotmail.com> on 19 Jan 2004:
>
> > Why are you asking these questions?
> >
> > (1) You don't know the answers, but are too dumb to use a library or
> > the Net to find them.
> >
> > (2) You don't know the answers, but hope that someone here who doesn't
> > know the answers either will reply in a way that you can use to
> > support your crackpot ideas.
> >
> > (3) You know the answers, but they scare you so much that you have to
> > pretend you don't, and hope someone here who doesn't know them will
> > reply in a way that you can use to support your crackpot ideas.
> >
> > (4) You know the answers, but think that posing these questions will
> > suggest to others that they constitute a problem for evolutionary
> > theory when they don't.
>
> Feel free to speculate all you want about my motivations for asking
> questions.
>
> Batch #2 of questions for John W. regarding Bell:
is this all you are going to do, david? I thought the idea was that you
would make claims, I would reply, and you would defend them. All you are
doing, though, is posing "challenges" and then not responding. It is not
worth my while responding if you don't.
Also, what is with the Sean Pitman stuff below? That is off-topic. Are
you just trying to divert attention from your lack of response? So far I
have replied in detail recently to three of your posts. I have argued
that you are wrong about "blindwatchmaking", that you have not shown
that natural selection was in decline as a mechanism of evolution in or
around 1932, and that you have misunderstood some of Bell's claims. Your
reply? Nada. Nothing. I may as well never have typed a word.
So before we move on, reply to my posts, or admit that you are just
trawling.
n
n '
gen2rev
<matts...@ix.netcom.nospamcom> wrote in
<t25p005ccuqaqs48e...@4ax.com>:
Very true.
> >But I'd have to disagree with Al that barring mutation there would be
> >millions of species like this, since recombination of genes from the two
> >parents in sexually reproducing species will *always* result in
> >variation.
>
> I suspect that baring mutations life would die out since species
> could not adapt to new conditions.
Well... I've read someplace (and since I can't remember where I'd take
it with a grain of salt) that recombination can mix previously separate
traits, and provide a certain amount of adaptation, but yes, mutation is
the wellspring of new traits. If there's a change in environment, the
Whiptail's days are numbered.
> >My original point (perhaps not stated strongly enough) was that there
> >has to be variation to test natural selection. A species that has no
> >variation in genotypes wouldn't be much of a test one way or the other.
>
> Sure. Selection is always a comparison, at least how we usually
> mean it.
I don't think of it was a comparison, unless you're talking about sexual
selection. But in natural selection, I'd argue that there's no
comparison at all, and "each case is judged individually", so to speak.
gen2rev
wrote in <sh2p00p5ooap7plas...@Pern.rk>:
> On Mon, 19 Jan 2004 22:13:08 +0000 (UTC), gen2rev
> <gen...@crosswinds.net> posted in alt.atheism:
>
> >But I'd have to disagree with Al that barring mutation there would be
> >millions of species like this, since recombination of genes from the two
> >parents in sexually reproducing species will *always* result in
> >variation.
>
> But there are millions of asexual species.
Damn, I forgot about those. I guess I'm just obsessed with sex...
Al Klein
<gen...@crosswinds.net> posted in alt.atheism:
>On Tue, 20 Jan 2004 01:57:44 +0000 (UTC), Al Klein <ruk...@pern.invalid>
>wrote in <sh2p00p5ooap7plas...@Pern.rk>:
>
>> On Mon, 19 Jan 2004 22:13:08 +0000 (UTC), gen2rev
>> <gen...@crosswinds.net> posted in alt.atheism:
>>
>> >But I'd have to disagree with Al that barring mutation there would be
>> >millions of species like this, since recombination of genes from the two
>> >parents in sexually reproducing species will *always* result in
>> >variation.
>>
>> But there are millions of asexual species.
>
>Damn, I forgot about those. I guess I'm just obsessed with sex...
People usually forget that there are THREE classes of life, not just
two - plant, animal ... and bacterial. And there are (at least)
millions of "species" of bacteria. (Since inability to interbreed
isn't applicable, do bacteria really have species?)
--
"I cannot conceive of a God who rewards and punishes his creatures, or has a will of the
type of which we are conscious in ourselves. An individual who should survive his
physical death is also beyond my comprehension,...; such notions are for the fears or
absurd egoism of feeble souls."
John Wilkins
> On Thu, 22 Jan 2004 02:59:04 +0000 (UTC), gen2rev
> <gen...@crosswinds.net> posted in alt.atheism:
>
> >On Tue, 20 Jan 2004 01:57:44 +0000 (UTC), Al Klein <ruk...@pern.invalid>
> >wrote in <sh2p00p5ooap7plas...@Pern.rk>:
> >
> >> On Mon, 19 Jan 2004 22:13:08 +0000 (UTC), gen2rev
> >> <gen...@crosswinds.net> posted in alt.atheism:
> >>
> >> >But I'd have to disagree with Al that barring mutation there would be
> >> >millions of species like this, since recombination of genes from the two
> >> >parents in sexually reproducing species will *always* result in
> >> >variation.
> >>
> >> But there are millions of asexual species.
> >
> >Damn, I forgot about those. I guess I'm just obsessed with sex...
>
> People usually forget that there are THREE classes of life, not just
> two - plant, animal ... and bacterial. And there are (at least)
> millions of "species" of bacteria. (Since inability to interbreed
> isn't applicable, do bacteria really have species?)
There are considered to be five kingdoms of life:
Monera (prokaryotic cells without a nuclear membrane)
further divided into eubacteria, cyanobacteria and archeabacteria.
Protista (protozoans and algae, eukaryotes)
Fungi
Platae
Animalia
The last four kingdoms form a single branch on the tree of life based on
ssRNA subunit phylogenies. Monera forms a complex tree. The subdivisions
of Monera are hotly debated right now - others who actually know what
they are talking about can fill in the details, but here's a URL
<http://waynesword.palomar.edu/trfeb98.htm>
Most bacteria do exchange genes. They don't do it all the time (some do)
and they don't do it via haploid reduction and secondary recombination
(some do) and they don't have genders (some do). However, "sex" is
usually applied to meiotic reduction and genders.
To define species in terms of reproductive isolation only works for
metazooans. It doesn't even work for all of them, and it is broadly
difficult to apply to plants, in particular flowering plants and ferns.
As I have noted in print, if the "normal" mode of something turns out to
be the exception rather than the rule, something is wrong with how we
define "normal".
Bacteria do have species. They form what one author (Eigen, for those
who know) calls "quasispecies" - clouds of genotypes that have an
average (modal) "wildtype". He defined this for viruses, but it works
for any asexual lineages and also for chemical species. Moreover, these
behave evolionarily like "normal" species, and so rather than treat them
as "exceptions", I prefer to treat sexual reproduction as a special case
of the class of mechanisms that forms species. In the case of
"quasispecies", that is selection for the wildtype genome. In the case
of sexual species, that is selection for sexual compatibility.
When I say "forms" species here, I do not mean that selection is the
reason why either asexual species or sexual species evolve in the first
instance. Selection acts as a secondary process in most cases (some
don't) to maintain the isolation of species. If it didn't, then we'd
merely treat "species" as temporary varieties within a larger taxon, and
call *that* a species. We see what hangs about, for whatever reason.
"Species" are whatever is maintained as a distinct inclusive lineage
from its closest relatives, and has no included lineages that are
maintained separately. "Maintained" merely means there is a causal
process operating at evolutionary timescales. The member units of
species are organisms and so gene lineages are not included in that
definition.
--
John Wilkins
wilkins.id.au
"Men mark it when they hit, but do not mark it when they miss"
- Francis Bacon
TomS
<1g80qkl.93rnx4wyumw2N%john.w...@bigpond.com>, John Wilkins stated..."
>
>Al Klein <ruk...@pern.invalid> wrote:
>
>> On Thu, 22 Jan 2004 02:59:04 +0000 (UTC), gen2rev
>> <gen...@crosswinds.net> posted in alt.atheism:
>>
>> >On Tue, 20 Jan 2004 01:57:44 +0000 (UTC), Al Klein <ruk...@pern.invalid>
>> >wrote in <sh2p00p5ooap7plas...@Pern.rk>:
>> >
>> >> On Mon, 19 Jan 2004 22:13:08 +0000 (UTC), gen2rev
>> >> <gen...@crosswinds.net> posted in alt.atheism:
>> >>
>> >> >But I'd have to disagree with Al that barring mutation there would be
>> >> >millions of species like this, since recombination of genes from the two
>> >> >parents in sexually reproducing species will *always* result in
>> >> >variation.
>> >>
>> >> But there are millions of asexual species.
>> >
>> >Damn, I forgot about those. I guess I'm just obsessed with sex...
>>
>> People usually forget that there are THREE classes of life, not just
>> two - plant, animal ... and bacterial. And there are (at least)
>> millions of "species" of bacteria. (Since inability to interbreed
>> isn't applicable, do bacteria really have species?)
>
>There are considered to be five kingdoms of life:
>
>Monera (prokaryotic cells without a nuclear membrane)
>further divided into eubacteria, cyanobacteria and archeabacteria.
>
>Protista (protozoans and algae, eukaryotes)
>
>Fungi
>
>Platae
Stamp out flat life forms?
---Tom S.
"There is nothing in the Animal Machine ... more capable of producing the
wonderful Fabrick of another Animal, than a thing is of making itself."
Cotton Mather, The Christian Philosopher(1720), Essay 27
catshark
wrote:
You're not making fun of 9 fingered typists are you?
Which raises an interesting methodological question. Would it be possible,
by examining a large sample of Wilkinsonian typos, to deduce which finger
he has carelessly mislaid?
---------------
J. Pieret
---------------
Nunc Id Vides, Nunc Ne Vides
- Unseen University Motto -
howard hershey
John Wilkins wrote:
Some people do consider there to be three major divisions in life: but
they propose eucaryote, eubacterial, and archaebacterial as the
divisions rather than plant, animal, and bacterial. The divisions given
above are merely the ramblings of some eucaryocentric thinkers. Four
eucaryotic divisions equated to one bacterial, hrummpf.
>
> Most bacteria do exchange genes. They don't do it all the time (some do)
> and they don't do it via haploid reduction and secondary recombination
> (some do) and they don't have genders (some do). However, "sex" is
> usually applied to meiotic reduction and genders.
>
> To define species in terms of reproductive isolation only works for
> metazooans.
Well, *most* eucaryotic species. Yeasts and other protists undergo the
same sexual cycle (2n-meiosis-1n-fusion-2n) as do other eucaryotes and
so can exhibit reproductive isolation. And it is the existence of a
sexual cycle that determines reproductive isolation.
> It doesn't even work for all of them, and it is broadly
> difficult to apply to plants, in particular flowering plants and ferns.
When a eucaryotic organism secondarily loses all ability to engage in
the sexual cycle, it becomes a clonal organism reproducing solely
vegetatively and thus genetically like bacteria. A number of metazoan
organisms, including both plants and animals (but mostly plants) have
secondarily lost the sexual cycle. They are reproductively isolated
from other species, of course, in the same way that bacterial species
are. And are related to other plants derived from the same ancestor in
the same way that bacteria are. The only *exchange* of genetic
information possible in these species are horizontal events like viral
transfer.
Of course, in metazoans, such asexual species *tend* to be
evolutionarily short lived. But there are exceptions.
John Wilkins
Which is effectively what I said in the preceeding paragraph :-)
Personally I think the three domain hypothesis is most likely, but the
point remains that animals and plants are a small couple of branches on
the overall tree.
> >
> > Most bacteria do exchange genes. They don't do it all the time (some do)
> > and they don't do it via haploid reduction and secondary recombination
> > (some do) and they don't have genders (some do). However, "sex" is
> > usually applied to meiotic reduction and genders.
> >
> > To define species in terms of reproductive isolation only works for
> > metazooans.
>
> Well, *most* eucaryotic species. Yeasts and other protists undergo the
> same sexual cycle (2n-meiosis-1n-fusion-2n) as do other eucaryotes and
> so can exhibit reproductive isolation. And it is the existence of a
> sexual cycle that determines reproductive isolation.
Well, it is the existence of barriers of any kind to the exchange of
genetic material that determines *reproductive* isolation. Why it has to
include a sexual cycle, other than a metazooan bias, I don't know.
>
> > It doesn't even work for all of them, and it is broadly
> > difficult to apply to plants, in particular flowering plants and ferns.
>
> When a eucaryotic organism secondarily loses all ability to engage in
> the sexual cycle, it becomes a clonal organism reproducing solely
> vegetatively and thus genetically like bacteria. A number of metazoan
> organisms, including both plants and animals (but mostly plants) have
> secondarily lost the sexual cycle. They are reproductively isolated
> from other species, of course, in the same way that bacterial species
> are. And are related to other plants derived from the same ancestor in
> the same way that bacteria are. The only *exchange* of genetic
> information possible in these species are horizontal events like viral
> transfer.
In this case, though, I was pointing the other way - ferns are mostly
speciated through allopolyploidy, and around half of all angiosperms are
too.
>
> Of course, in metazoans, such asexual species *tend* to be
> evolutionarily short lived. But there are exceptions.
Darwinulian ostracods and bdelloid rotifers are the main examples in the
animal realm. Plants and fungi of course have more. These are sometimes
referred to as "ancient asexuals":
Judson, Olivia P., and Benjamin B. Normark. 1996. Ancient asexual
scandals. Trends in Ecology and Evolution 11 (2):41-46.
Schön, Isabelle, Roger K. Butlin, Huw I. Griffiths, and Koen Martens.
1998. Slow molecular evolution in an ancient asexual ostracod.
Proceedings of the Royal Society of London - Series B: Biological
Sciences 265:235-242.
Welch, David B. Mark, and Matthew S. Meselson. 2001. Rates of nucleotide
substitution in sexual and anciently asexual rotifers. Proceedings of
the National Academy of Sciences of the United States of America 98
(12):6720-6724.
...
Copies of my species paper will be mailed on request (to
<mailto:wil...@wehi.edu.au.SPAMM> (remove the obvious)