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Natural Science Forum / Biology / Paleontology / December 2005



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TOBS: The Cambrian Outburst, comments from Alfred Romer

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JaBrIoL - 03 Oct 2003 15:04 GMT
Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
there are vast thicknesses of sediments in which the progenitors of
the Cambrian forms would be expected. But we do not find them; these
older beds are almost barren of evidence of life, and the general
picture could reasonably be said to be consistent with the idea of a
special creation at the beginning of Cambrian times."-Natural History,
October 1959, p. 467.
David Jensen - 03 Oct 2003 15:08 GMT
In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
<d222de3e.0310030604.2976a410@posting.google.com>:

>Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
>there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 3 lines]
>special creation at the beginning of Cambrian times."-Natural History,
>October 1959, p. 467.

Forty four years old and a short snip from a magazine that popularizes
science.

Give up your lies Jabs.
jabriol - 04 Oct 2003 02:25 GMT
> In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
> <d222de3e.0310030604.2976a410@posting.google.com>:
[quoted text clipped - 11 lines]
>
> Give up your lies Jabs.

what lies?
your saying the quote is not legit...
Arne Vogel - 04 Oct 2003 18:49 GMT
>> In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
>> <d222de3e.0310030604.2976a410@posting.google.com>:
[quoted text clipped - 14 lines]
> what lies?
> your saying the quote is not legit...

Since creationists distort 99 out of 100 quotes that's a valid initial
hypothesis.

Signature

Arne Vogel

JaBrIoL - 05 Oct 2003 13:56 GMT
> >> In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
> >> <d222de3e.0310030604.2976a410@posting.google.com>:
[quoted text clipped - 17 lines]
> Since creationists distort 99 out of 100 quotes that's a valid initial
> hypothesis.

I am not a creationist, and I ask you again... are you saying the
quote is not legit? Are yo saying it is fabricated?
David Jensen - 05 Oct 2003 16:22 GMT
In alt.talk.creationism (sbp removed from followup), Jabriol@excite.com
(JaBrIoL) wrote in <d222de3e.0310050456.6fedf4ce@posting.google.com>:

>> >> In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
>> >> <d222de3e.0310030604.2976a410@posting.google.com>:
[quoted text clipped - 20 lines]
>I am not a creationist, and I ask you again... are you saying the
>quote is not legit? Are yo saying it is fabricated?

With any religious zealot, it is hard to tell, not having access to the
original article, but you quote as if you are quoting from the article,
so please provide the paragraphs that surround this quote. If you got
this quote from a secondary source, it is your responsibility to
document the source and let us know that it is all you have.

I'm saying that it is out of date and misleadingly selective and that it
is from a well-regarded popular science magazine rather than a science
journal. It proves nothing.

Please check on groups.google.com for the threads on quote mining in
talk.origins. The lies of quote mining are the selective quotation, akin
to saying that the Bible says 'there is no God'.

Why do you have to post to so many newsgroups?
MarcRW - 05 Oct 2003 17:03 GMT
> > >> In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
> > >> <d222de3e.0310030604.2976a410@posting.google.com>:
[quoted text clipped - 20 lines]
> I am not a creationist, and I ask you again... are you saying the
> quote is not legit? Are yo saying it is fabricated?

I'd say it's 100% worthless.  Dated, superceded by new information.
Worthless, and pointless for you to post.

Marc
jabriol - 05 Oct 2003 23:17 GMT
> > Arne Vogel <arne@123soft.de> wrote in message
> news:<bln1an$mlu$00$1@news.t-online.com>...
[quoted text clipped - 30 lines]
>
> Marc

totally different than acussing me of lying or providing false information.
David Jensen - 06 Oct 2003 01:09 GMT
In alt.talk.creationism, "jabriol" <jabriol@Neogenesis.net> wrote in
<eM0gb.671860$Ji7.7358109@news.easynews.com>:

>> > Arne Vogel <arne@123soft.de> wrote in message
>> news:<bln1an$mlu$00$1@news.t-online.com>...
[quoted text clipped - 35 lines]
>
>totally different than acussing me of lying or providing false information.

Show me the paragraphs to each side of the quote to show that your quote
was legitimate and in context. We've seen enough of your behavior not to
trust you.
MarcRW - 06 Oct 2003 02:18 GMT
> > I'd say it's 100% worthless.  Dated, superceded by new information.
> > Worthless, and pointless for you to post.
> >
> > Marc
>
> totally different than acussing me of lying or providing false information.

No.  You were your intent was to mislead.  You did so by omission.  You
lied.

Marc
JaBrIoL - 06 Oct 2003 11:41 GMT
> > > I'd say it's 100% worthless.  Dated, superceded by new information.
> > > Worthless, and pointless for you to post.
[quoted text clipped - 8 lines]
>
> Marc

A mind reader we have here, do we?
I thought atheist were against the supernatural..
Arne Vogel - 06 Oct 2003 14:18 GMT
>> >> In alt.talk.creationism, Jabriol@excite.com (JaBrIoL) wrote in
>> >> <d222de3e.0310030604.2976a410@posting.google.com>:
[quoted text clipped - 20 lines]
> I am not a creationist, and I ask you again... are you saying the
> quote is not legit? Are yo saying it is fabricated?

No, I say it's at least *ancient*. I haven't verified it.

What I said was a general remark about how I
(and others) feel quotations are frequently misrepresented
by believers in Creationism.

And don't tell me creationists do not distort quotes...
I might come up with counter-examples.

Btw, the way *I* define a lie (others may see it differently)
is *not* to say something untrue (can be, and most often is,
by lack of better knowledge), but deliberate deceit.

This is in effect how the American Heritage Dictionary
sees it:

1. A false statement deliberately presented as being true; a falsehood.
2. Something meant to deceive or give a wrong impression.

As definition 2 shows, you can lie while saying the truth.

Like in "I didn't kill him!" ("... but I hired his killer.")

Posting superceded information with the purpose of fooling
newsgroup readers thus means lying. Except you didn't know
better yourself, and are just ignorant.

P.S.: It's possible to distort a quote by literally copying it --
out of context. See Darwin's "eye quote".

Signature

Arne Vogel

Lane Lewis - 03 Oct 2003 21:06 GMT
> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 3 lines]
> special creation at the beginning of Cambrian times."-Natural History,
> October 1959, p. 467.

Do you intentionally try to deceive people with outdated material.

In 1989 Stephen Jay Gould, concerning the earliest life, said there is a
rich Precambrian record, all discovered in the past thirty years... Our
Precambrian record now stretches back to the earliest rocks that could
contain life... morphological remains are... as old as they could possibly
be. Both stromatolites (mats of sediment trapped and bound by bacteria and
blue-green algae) and actual cells have been found in the earth's oldest
unmetamorphosed sediments, dating to 3.5-3.6 billion years in Africa and
Australia... The Precambrian record does contain one fauna of multicellular
animals preceding the Cambrian explosion, the Ediacara fauna, named for a
locality in Australia but now known from rocks throughout the world. But
this fauna... is barely Precambrian in age. These animals are found
exclusively in rocks just predating the explosion, probably no more than 700
million years old and perhaps younger... the Ediacara creatures are
soft-bodied, and they are not confined to some odd enclave stuck away in a
peculiar Australian environment; they represent a world-wide fauna.

   A. Romer might have been right in 1959 but is definitely wrong today.

Lane
MarcRW - 04 Oct 2003 03:31 GMT
> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 3 lines]
> special creation at the beginning of Cambrian times."-Natural History,
> October 1959, p. 467.

You can't come up with a more recent source that supports your point?
Pretty weak!

Marc
Arne Vogel - 04 Oct 2003 18:51 GMT
>> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
>> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 8 lines]
>
> Marc

The point about Creationism is not coming up with more recent sources,
but with more *ancient* sources! In creationist thinking, it makes
perfect sense to point out that scientists who lived centuries before
Darwin did not believe in evolution.

Signature

Arne Vogel

JaBrIoL - 05 Oct 2003 13:54 GMT
> >> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> >> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 13 lines]
> perfect sense to point out that scientists who lived centuries before
> Darwin did not believe in evolution.

I am not a creationist, and I have posted recent articles, which has
been conviently ignored..
for example, new scientist article of plant evolution. it basicly
knowcks down all previous theories on plant evolution.

where you criticism on that?

the article is still hot off the press..
Eric Gill - 06 Oct 2003 13:35 GMT
<snip>

> I am not a creationist,

You are a poor liar.
Arne Vogel - 06 Oct 2003 14:29 GMT
>> >> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
>> >> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 16 lines]
> I am not a creationist, and I have posted recent articles, which has
> been conviently ignored..

How do you define "creationist" in this regard? E.g. are you just
skeptical of common descent or you disagree entirely?
Do you believe that G*d or however you may call your deity
zipped humans into existence or that they evolved from apes?
Do you believe that all life on Earth has a universal common
ancestor? Do you believe that abiogenesis is possible?
Come on, you must have *some* kind of belief in creation
that's incompatible with the Theory of Evolution or
the Theory of Abiogenesis. Or why are you posting all this?

> for example, new scientist article of plant evolution. it basicly

Popular science is not science. New scientist also reported
on "cold fusion" before it turned out to be an experimental mistake.

> knowcks down all previous theories on plant evolution.

Which in turn proves that mammals have no common ancestor
and that the Earth is young and...

> where you criticism on that?
>
> the article is still hot off the press..

But this one isn't. Pre-Cambrian fossils have been found since.
What would be the point if I quoted some famous Greek
philosopher saying there is no evidence for the existence of
atoms. Or a renowned mathematician who said that given
300 years of failed attempts, Fermat's
Last Theorem is very likely in the realm of true, but
unprovable statements (it was eventually proven in 1995).

Do you agree that a reader who lacks knowledge of
the discoveries that happened *since*, might easily
be mislead by such an uncommented quotation?

Signature

Arne Vogel

Budikka - 18 Oct 2003 23:54 GMT
Jabriol, you may as well snip now, because this is never going to stop
and it is only going to get worse for you as time goes on.  Here, let
me help you:
SNIP SNIP SNIP SNIP SNIP SNIP SNIP SNIP SNIP SNIP

> I am not a creationist, and I have posted recent articles, which has
> been conviently ignored.

Is that why you refered us to the Genesis creation story in one of
your posts?

> for example, new scientist article of plant evolution. it basicly
> knowcks down all previous theories on plant evolution.
>
> where you criticism on that?
>
> the article is still hot off the press..

I have tackled you on many of your so-called "recent articles" and you
have fled from every single one of them, thereby proving evolution in
that you have evolved before my eyes from a jackass to a chicken.

Just because you have recently posted a pirated article that itself is
20 or 50 years old doesn't make it a recent article.

Once again I note that you very conveniently give no reference to this
"evolution shattering article" for us to check.  This is not
surprising since I am still waiting on you providing one to support
your claim that human DNA and banana DNA are 90% - no! it was 75%, no!
it was 60%, no! it was 50% - the same.  The one reference you gave to
me proved you to be a liar since it actually said we *may* share *up
to 30%* of our DNA, and made not a single mention of 75%.

I note that you did give a different reference in another thread that
I was not, at the time, involved in:
"Robert May is a UK Chief Scientist. In New Scientist magazine (July
1, 2000) on page 5 he stated, "We share half our genes with the
banana."

This is actually a statement, not a scientific demonstration of the
statement (you *can* tell the difference, presumably).  Unfortunately,
for you, I was able to look this one up on line.  I searched the _New
Scientist_ archives for the month of July 2000 (page 5) for both
"banana" and for "Robert May" and both searches came up blank.  Only
one mention of banana turned up in any edition for any page for that
month and that was simply a passing reference to local flora.

I can only conclude from this that you are either outright lying
again, which you have repeatedly been shown to do, or you have simply
got your "facts" totally screwed up yet again, which you have
repeatedly been shown to do.  I give up - which one is it?

While you're cogitating on that, please give some thought to answering
my other challenges, many of which I have been putting to you since
late August.  You claim right here in this thread that no one tackles
your questions.  That's simply another lie!

I have been able and willing to do that for 2 months now, and yet you
quietly have abandoned every single thread in which I have begun to
discuss your material with you, with all of my questions unaswered.
Is it something I said - like an unfortunate fact that you can't
handle - or what?

Just as a reminder, here is some of the unfinished business:
1. I am *still waiting* for you to admit that regardless of what it is
classed as, and regardless of whether it was or was not in the line to
birds, the archaeopteryx had pretty much a fifty-fifty mix of
reptile/dino and bird features and therefore represented an example of
a potential intermediate stage.

2. I am *still waiting* for you to admit that the okapi is pretty much
what a transitional giraffe would have looked like.

3. I am *still waiting* for you to explain why something akin to a
mouse, could not change 300 genes over 60 million years to become
either human or a modern mouse.

4. I am *still waiting* for you to acknowledge that no evolutionist
has ever claimed that modern birds evolved from modern reptiles and
that argument from incredulity addressing this non-issue, no matter
how ancient it is, does not constitute a "colossal hole" in the Theory
of Evolution.

5. I am *still waiting* for you to acknowledge that creationist
letters published as a courtesy (or maybe as a source of amusement) in
_New Scientist_ are *not* the equivalent of peer-reviewed science
papers, no matter how ancient and misguided they are.

6.  I am *still waiting* for you to post a **LIST** of these "colossal
holes" in the Theory of Evolution that you were blathering hopelessly
about back in August.

Any response to this that does not address these questions will be a
direct and open admission by you that you cannot answer them and that
each of the threads you started with your plagiarized material, that
these questions remain unanswered in, were nothing but useless banter
and lies.

Budikka
jabriol - 19 Oct 2003 01:34 GMT
> Jabriol, you may as well snip now, because this is

ok....................................SNIP..................................
.....................................
Budikka - 19 Oct 2003 00:14 GMT
> I am not a creationist,

Then I would be thrilled if you could explain why you began a thread called:
"TOBS: The Fossil record support's Genesis"
http://tinyurl.com/rg0r

Or is this yet another lie we can add to the Jabriol stable?

Budikka
Steven J. - 19 Oct 2003 06:14 GMT
> > I am not a creationist,

The primary meaning of "creationist," if no qualifying terms are attached,
is "young-earth, six-24-hour-day special creationist."  Jehovah's Witnesses
do not interpret the days of Genesis as 24-hour days, but as long periods of
time (7000 years at least, and I think many JWs nowadays accept a 4.55
billion year old earth).  Since Jabriol is an old-earth progressive
creationist, not an AiG-style YEC, he doesn't consider himself a
"creationist."

> Then I would be thrilled if you could explain why you began a thread called:
> "TOBS: The Fossil record support's Genesis"
> http://tinyurl.com/rg0r
>
> Or is this yet another lie we can add to the Jabriol stable?

No, once in a while he says something that, allowing for unusual (but not
idiosyncratic or intentionally deceptive) meanings of certain words.

> Budikka

-- Steven J.
prabbit1@shamrocksgf.com - 19 Oct 2003 21:27 GMT
>> Jabriol@excite.com (JaBrIoL) wrote in message
>news:<d222de3e.0310050454.2d31d107@posting.google.com>...
[quoted text clipped - 8 lines]
>creationist, not an AiG-style YEC, he doesn't consider himself a
>"creationist."

He's a cretinist^H^H^H^H^H^H^Hcreationist. Creationist, with no
qualifiers, simply means "a doctrine or theory holding that matter,
the various forms of life, and the world were created by God out of
nothing and usually in the way described in Genesis" (from
www.m-w.com.) Key here is the word "usually." That means that most
creationists believe it happened the way the bible says. But it
doesn't require that to be a part of being a creationist. If you
believe that "the [universe (matter, life and the world)] was created
by [a] god" then you fit the definition. So he is a creationist no
matter how much he lies^H^H^H^Hdenies it.

>> Then I would be thrilled if you could explain why you began a thread
>called:
[quoted text clipped - 5 lines]
>No, once in a while he says something that, allowing for unusual (but not
>idiosyncratic or intentionally deceptive) meanings of certain words.

No, he's just trying to decieve with his wording. He knows that we use
the general term here. If he's trying to use some more specific term
without qualifying it, especially after he's been corrected, then he
IS being intentionally deceptive.

---
Mike                               atheism: a non-prophet
organization...
Creation Science: an oxymoron actually created by morons...
-------------------------------
Before you criticize someone, walk a mile in their shoes. That way
when you do criticize them, you're a mile away, and you have their
shoes.
-------------------------------
Zachriel - 05 Oct 2003 17:52 GMT
> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 3 lines]
> special creation at the beginning of Cambrian times."-Natural History,
> October 1959, p. 467.

Though you didn't provide the context, Romer was an expert vertebrate
paleontologist.
http://www.nceas.ucsb.edu/~alroy/lefa/Romer.html

At that time, reliable evidence only extended back to the Cambrian. There
were two hypotheses in 1959. Special Creation at the beginning of the
Cambrian, or undetected evolution leading up to the Cambrian. Both
hypotheses accept that life evolved from that point forward, meaning there
is no Special Creation of humankind. Do you share one of these hypotheses?

But as usual, the hypothesis of Special Creation was falsified, while the
evolutionary prediction of living precursors leading up to the Cambrian was
validated. JaBrIoL has provided an excellent cite that demonstrates the
historic power of the Theory of Evolution as a predictive science, in this
case predicting observations to be made over the next three decades. Keep up
the good work!

Fossils from the Precambrian
http://www.members.aol.com/drjohnsea/Vendianfossils.html
JaBrIoL - 06 Oct 2003 02:43 GMT
> > Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> > there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 23 lines]
> Fossils from the Precambrian
> http://www.members.aol.com/drjohnsea/Vendianfossils.html

a pleasure...
prabbit1@shamrocksgf.com - 07 Oct 2003 01:06 GMT
>> > Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
>> > there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 25 lines]
>
>a pleasure...

Sarcasm is so lost on the ignorant. Hey, Jabriol, he WAS being
sarcastic there. You were actually helping the other side with your
posting above and hurting your own position.

---
Mike                               atheism: a non-prophet
organization...
Creation Science: an oxymoron actually created by morons...
-------------------------------
Before you criticize someone, walk a mile in their shoes. That way
when you do criticize them, you're a mile away, and you have their
shoes.
-------------------------------
jabriol - 07 Oct 2003 10:47 GMT
> >> > Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> >> > there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 29 lines]
> sarcastic there. You were actually helping the other side with your
> posting above and hurting your own position.

DUH...

what position exactly?
prabbit1@shamrocksgf.com - 12 Oct 2003 02:31 GMT
>> >"Zachriel" <angel@zachriel.com> wrote in message
>news:<40Yfb.1029$RC.577955910@twister2.starband.net>...
[quoted text clipped - 43 lines]
>
>what position exactly?

You don't even know what your own position is? I guess the "DUH" was
appropriate then, eh?

---
Mike                               atheism: a non-prophet
organization...
Creation Science: an oxymoron actually created by morons...
-------------------------------
Before you criticize someone, walk a mile in their shoes. That way
when you do criticize them, you're a mile away, and you have their
shoes.
-------------------------------
Harry Erwin - 06 Oct 2003 18:34 GMT
> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 3 lines]
> special creation at the beginning of Cambrian times."-Natural History,
> October 1959, p. 467.

And?

He was referring to what was generally known about the Precambrian in
1959. We now have much better data, and there is now evidence for life
that goes back nearly to heavy bombardment era. I had the pleasure of
talking with him once many years ago, and he would hardly have been
called a creationist.
Signature

Harry Erwin <http://www.theworld.com/~herwin/>

jabriol - 06 Oct 2003 21:17 GMT
> > Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> > there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 13 lines]
> --
> Harry Erwin <http://www.theworld.com/~herwin/>

Is there anyplave in my post, where I called him a creationist?
Harry Erwin - 07 Oct 2003 19:19 GMT
> > > Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
> > > there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 15 lines]
>
> Is there anyplave in my post, where I called him a creationist?

No, but you cited him out of context. That's an academic sin, akin to
uncritical use of what some scholars believe may be the original text of
Mark (see Smith, Morton, the Secret Gospel, Harper and Row, 1973, as
quoted in Allegro, John, the Dead Sea Scrolls and the Christian Myth,
Prometheus Books, 1984, p. 242 or see Funk et al., the Acts of Jesus,
HarperCollins, 1998, 115-117) as ammunition in the current controversy
about sexual orientation of priests in the Church of England.
Signature

Harry Erwin <http://www.theworld.com/~herwin/>

Don Kenney - 09 Dec 2005 14:29 GMT
>> Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
>> there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 11 lines]
>talking with him once many years ago, and he would hardly have been
>called a creationist.

True enough.  But in fairness, the "Cambrian Explosion" is still about
as much of a mystery as it was in the 1960s before it was named.  Sure
we know a lot more about life before trilobites.  But we also know a
lot more about the very great diversity and complexity of life in the
Early Cambrian.  ... and except for sponges we don't have anything
remotely resembling an X begot Y lineage for any of the major metazoan
phyla prior to their rather abrupt appearance around 530 million year
ago.

I'd venture to say that there are no more than 10 identified
Precambrian forms that have any credibility at all as possible
precursors of modern life.  And I'd guess that when we eventually sort
them out, most of them probably will turn out not to be what we think
they are.

I think we're about four decades away from throwing in the towel on
figuring out where all those critters in the Maotianshan shale and
similar formations came from.  And my guess is that we will eventually
work it out.

But lets don't claim to know more than we do.
John Harshman - 09 Dec 2005 18:01 GMT
>>>Paleontologist Alfred Romer wrote: "Below this [Cambrian period],
>>>there are vast thicknesses of sediments in which the progenitors of
[quoted text clipped - 20 lines]
> phyla prior to their rather abrupt appearance around 530 million year
> ago.

What exactly do you mean by an "X begot Y lineage"?

> I'd venture to say that there are no more than 10 identified
> Precambrian forms that have any credibility at all as possible
> precursors of modern life.  And I'd guess that when we eventually sort
> them out, most of them probably will turn out not to be what we think
> they are.

Or we may never sort them out. The preservation of ediacaran fossils is
not good enough to provide a lot of clues, as should be obvious from
controversies over whether some of them are arthropods or cnidarians.
Still, the Doushantuo phosphatized embryos found recently suggest that
there may be some better clues awaiting us; if only they were at a bit
later developmental stage.

> I think we're about four decades away from throwing in the towel on
> figuring out where all those critters in the Maotianshan shale and
> similar formations came from.  And my guess is that we will eventually
> work it out.

Actually, the Cambrian deposits themselves provide some clues, in the
person of various intermediate forms. There are also clues in the record
of trace fossils and the "small shelly fauna".

> But lets don't claim to know more than we do.

Or less.
don kenney - 12 Dec 2005 16:35 GMT
>What exactly do you mean by an "X begot Y lineage"?

You can draw a chain of ancestry from the last proetid trilobite that
died out in the P-Tr extinction event back to the first trilobite to
appear in the Cambrian (I think that'd be a Redlichid).  You might not
get every detail right, but it'd be mostly correct.  Beyond that, you
can't go.  You can construct a diagram of how the arthropods possibly
diverged from some protoarthropod which in turn evolved from some
protobilateran.  But all the forms before that first trilobite are, at
this point, entirely hypothetical.

With a few exceptions, very little older than the classical lower
Cambrian boundary (except the porifera) makes much sense at this point.
Even widespread forms like Pternidium and the cloudinids exist pretty
much in isolation.  It's not clear how they relate to their
contemporaries, to older forms, or if they have descendents.  Yes,
there are a few forms -- Kimberella for example -- that very likely
will help.  But I don't think there are (yet) enough of them to see
what the picture will look like when (/if) it is put together.

>Actually, the Cambrian deposits themselves provide some clues, in the
person of various intermediate forms. There are also clues in the
record
of trace fossils and the "small shelly fauna".

I absolutely agree that the forms from the classical Cambrian are
tractable.  Sorting all of them out won't be easy.  They are amazingly
numerous and diverse.  But I'll be suprised if that isn't pretty much
accomplished in the next three decades or so.  It's the 60 or 70
million years prior to that seem to me to present a problem.  And yes,
the Lower Cambrian faunas will provide clues and constraints on what
could have come before.  But it's not at all obvious that there won't
still be substantial questions about what went on between say 600Ma and
525 or 530Ma after all the results from later times are assimilated.

It certainly is possible that there is plenty of evidence out there in
the Ediacaran and Lowest Cambrian not yet found, or not yet recognized
that will pull it all together.  But I don't think one can be sure of
that today.
John Harshman - 12 Dec 2005 20:54 GMT
>>What exactly do you mean by an "X begot Y lineage"?
>
> You can draw a chain of ancestry from the last proetid trilobite that
> died out in the P-Tr extinction event back to the first trilobite to
> appear in the Cambrian (I think that'd be a Redlichid).  You might not
> get every detail right, but it'd be mostly correct.

No you can't. What you can do is get a cladogram and fudge the ancestry
by assuming that some of the taxa are ancestors. But real data won't
support those assumptions. The data themselves do not contain lineages.
They enable us to determine cladistic relationships, by which we can
infer common ancestry and even to some extent the appearance of the
ancestor. But don't confuse that with actual lineages.

> Beyond that, you
> can't go.  You can construct a diagram of how the arthropods possibly
> diverged from some protoarthropod which in turn evolved from some
> protobilateran.  But all the forms before that first trilobite are, at
> this point, entirely hypothetical.

That depends on what you mean by "before". There are certainly
non-trilobite arachnomorphs. They all postdate the earliest trilobites,
but so what? Don't confuse age with tree position, or tree position with
ancestry. This is the sort of sloppy thinking that paleontologists used
to indulge in 50 years ago, but let's hope that we are better at it now.

> With a few exceptions, very little older than the classical lower
> Cambrian boundary (except the porifera) makes much sense at this point.
[quoted text clipped - 4 lines]
> will help.  But I don't think there are (yet) enough of them to see
> what the picture will look like when (/if) it is put together.

You confuse age with illumination. There are plenty of Atdabanian or
later fossils that can illuminate the relationships of trilobites, other
arthropods, or other phyla, just as Cretaceous theropods can illuminate
the relationships of birds, even if they postdate Archaeopteryx.

>>Actually, the Cambrian deposits themselves provide some clues, in the
>
[quoted text clipped - 11 lines]
> still be substantial questions about what went on between say 600Ma and
> 525 or 530Ma after all the results from later times are assimilated.

I don't think the dates of fossils are as important as you do. We may
never know what happened between 600ma and 540ma, but mostly that means
we won't know exactly when particular evolutionary events happened. We
should be able to reconstruct those events and their ordering without
having fossils of that age.

> It certainly is possible that there is plenty of evidence out there in
> the Ediacaran and Lowest Cambrian not yet found, or not yet recognized
> that will pull it all together.  But I don't think one can be sure of
> that today.

Again, I don't think you are understanding the nature of the necessary
evidence here. We can, for example, reconstruct a great deal of the past
history of life without recourse to fossils at all.
don kenney - 16 Dec 2005 18:20 GMT
>No you can't. What you can do is get a cladogram and fudge the ancestry
>by assuming that some of the taxa are ancestors. ...

OK, ignoring your attempts to enlighten me, we agree.

>I don't think the dates of fossils are as important as you do. We may
>never know what happened between 600ma and 540ma, but mostly that means
>we won't know exactly when particular evolutionary events happened. We
>should be able to reconstruct those events and their ordering without
>having fossils of that age.

I agree that dates for the most part are not all important.  But I
suspect that you will need
some evolutionary data points from the Ediacaran to pull the logical
structure
built from Cambrian data into some sort of concurrence with reality.
Without them,
and we are currently pretty much without them, it is likely that every
tenth new piece
of data from the Cambrian will require revising the model.  It's not
even clear that revisions
to a model built that way will ever converge.

>We can, for example, reconstruct a great deal of the past
>history of life without recourse to fossils at all.

Perhaps.  I'd point out that our record in doing so hasn't always been
that great.  I'd
submit that no reputable paleontologist in 1950 would have projected
the Lower
Cambrian view that almost all paleontologists held in 2000.  Projecting
from the data
they had at hand, they'd have predicted a much simpler world.  And
logically, they
would have been correct to do so.

If your point is that we don't need all that much data to project
accurately, I agree.
But we need the right sort of data and the right framework to fit it
into.  I'm far from
convinced that we have either.
John Harshman - 17 Dec 2005 14:42 GMT
>>No you can't. What you can do is get a cladogram and fudge the ancestry
>>by assuming that some of the taxa are ancestors. ...
[quoted text clipped - 12 lines]
> structure
> built from Cambrian data into some sort of concurrence with reality.

Much of the data are actually from extant taxa. If we took your idea
literally, we would be unable to determine the phylogeny of anything
without fossils.

> Without them,
> and we are currently pretty much without them, it is likely that every
> tenth new piece
> of data from the Cambrian will require revising the model.  It's not
> even clear that revisions
> to a model built that way will ever converge.

I really don't see why that should be true. Explain.

>>We can, for example, reconstruct a great deal of the past
>>history of life without recourse to fossils at all.
[quoted text clipped - 14 lines]
> into.  I'm far from
> convinced that we have either.

Now you're talking about paleoecology, not evolution. I will agree that
we have no ready substitute for fossils in reconstructing paleoecology.
Don Kenney - 19 Dec 2005 23:39 GMT
>> Without them,
>> and we are currently pretty much without them, it is likely that every
[quoted text clipped - 4 lines]
>
>I really don't see why that should be true. Explain.

When one extrapolates either forward or backward, it's rare that one
is 100% confident of the projection.  But, extrapolation is necessary
or we'll spend decades waiting for certainty that will probably never
come.  So, we make guesses based on reasonable confidence -- say 90%.
If we then use that framework to make another 90% confidence guess,
the confidence level of the result isn't 90%.  It's 0.9^2 = 81%.  Do
that a few more times and we are looking at maybe 65% confidence or
56% confidence or less.  But some real data points will do wonders for
the projection by screening out chains of deduction that lead to
reasonable, but wrong answers.

I think that something like that happened to paleontologists in the
early-mid 20th Century.  They created a logical structure of how
evolution had gone during the Cambrian. and validated it  based on the
Trilobites and Brachiopods where there was a lot of data available.
The model was logical and it would probably have been a lot worse
without the trilobites and brachiopods.  But it turns out that there
seems to have been MUCH more diversity in the overall fauna than was
anticipated -- which is why the Burgess and Chenjiang faunas came as
such a suprise.  

All I'm trying to say is that without a few primitive bilaterans, and
a worm that is clearly working on being an arthropod or similar
evolutionary waypoints, there is a danger of building another
logically consistent, but not all that correct, model for the time
before Chenjiang.
John Harshman - 20 Dec 2005 01:50 GMT
>>>Without them,
>>>and we are currently pretty much without them, it is likely that every
[quoted text clipped - 15 lines]
> the projection by screening out chains of deduction that lead to
> reasonable, but wrong answers.

Agreed, but apparently you restrict the term "real data point" to some
kind of fossil. Why? And how does what you said before (the point I
asked about) follow from what you just said?

> I think that something like that happened to paleontologists in the
> early-mid 20th Century.  They created a logical structure of how
[quoted text clipped - 11 lines]
> logically consistent, but not all that correct, model for the time
> before Chenjiang.

This depends on what you are trying to model. Previous posts have
suggested various possibilities: phylogeny, paleoecology, or perhaps
some combination thereof. But what are you actually talking about? Do
you mean "what the world looked like" at some particular point in time,
perhaps as expressed in a nice museum diorama? Or what?
 
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