"John Harshman"
Fletis Humplebacker wrote:
John Harshman wrote:
Fletis Humplebacker wrote:
[snip]
Darwinian evolution predicts gradual change,
true, but the long periods are only with respect to human lifetimes, not
geological eras.
So when the experts in the field say lifeform appearances
are sudden we should discount their words? I think they
are aware of the time frames involved.
We shouldn't discount their words. We should understand what they mean:
sudden in geological terms. Look below at your Gould quote: "in a
geological moment", by which, if you read the whole quote, you will see
that he means a minimum of 5 million years.
That isn't in dispute, his reference is the geological record, not a
stop watch. The point is that it was, by all accounts I've seen so far,
sudden. Hense the term "explosion", which was contrary to the traditional
view of evolution.
STEPHEN J. GOULD, HARVARD, "The Cambrian Explosion occurred
in a geological moment, and we have reason to think that all major
anatomical designs may have made their evolutionary appearance at
that time. ...not only the phylum Chordata itself, but also all its major
divisions, arose within the Cambrian Explosion. So much for chordate
uniqueness... Contrary to Darwin's expectation that new data would
reveal gradualistic continuity with slow and steady expansion, all major
discoveries of the past century have only heightened the massiveness
and geological abruptness of this formative event..." Nature, Vol.377,
26 10/95, p.682
Gould had an axe to grind. You are right about one thing, that people
tend to interpret data to fit their theories. That's why science is a
social effort and can't depend on one person. Others have shown how
Gould misinterpreted some of what he saw. The Cambrian explosion may
have spawned most phyla, though we can't tell this from the fossil
record,
You know, you are constantly telling me to believe you and not my
lying eyes. You want to discount comments if they are quoted on
creationist sites then argue with them even if they aren't. You believe
that you know more about the fossil records than Gould did, that's fine
with me but don't expect me to come aboard that easily.
I do know more than Gould did at the time he wrote that. There are new
discoveries every day, and ten years can make a lot of difference. But
you are picking out little fragments of Gould that distort his meaning,
and lots of paleontologists disagree with even his real meaning.
And what did I distort? And no one suggested that evolutionists were
harmonious, in fact my point has been just the opposite.
I have
difficulties with his theory of how things happened but not with his
observations on what did happen. I've seen no evidence that his research
was sloppy.
So you pick what you like and throw away what you don't.
I thought that's what you were doing? I never took issue with what he
found, only his theory of why it was. Those are two separate things.
And Gould
actually did no research on the Cambrian explosion. He wrote a popular
book, and in his early years he did some simulations that bear on the
question, but that's it.
No research? That's hard to believe. surely he must have realized
it would be read by his peers. Not that I didn't believe you but I
looked into it and you are downplaying his research and role within
the scientific community.
http://www.arn.org/docs2/news/gouldobituary052702.htmn
Noting that in graduate school Dr. Gould dodged bullets and drug runners
to collect specimens of Cerion and their fossils, Dr. Sally Walker, who studies
Cerion at the University of Georgia, once said, "That guy can drive down the left
side of the road," which is required in the Bahamas, "then jump out the door and
find Cerion when we can't even see it."
March, Harvard University Press published what Dr. Gould described as his magnum
opus, "The Structure of Evolutionary Theory." The book, on which he toiled for decades,
lays out his vision for synthesizing Darwin's original ideas and his own major contributions
to macroevolutionary theory.
"It is a heavyweight work," wrote Dr. Mark Ridley, an evolutionary biologist at University
of Oxford in England. And despite sometimes "almost pathological logorrhea" at 1,433
pages, Dr. Ridley went on, "it is still a magnificent summary of a quarter-century of influential
thinking and a major publishing event in evolutionary biology."
and there are some phyla that clearly did not originate then.
Chordates and the major divisions of Cephalochordata, Urochordata, and
Vertebrata (or at least their stem groups) may well have originated in
the explosion. The explosion may have lasted as little as 5 million
years. But do you have any real idea how long 5 million years is?
Do you ever wonder, by the way, what used to be in the the ellipses in
all these quotes you get from creationist sites?
It would be difficult to believe that his words mean something other
than what was posted. If that's your claim why take issue with Gould?
You do cover your bases.
There are multiple levels. Gould was wrong about many things, and you
(or the creationist sites you pull these highly trimmed quotes from)
distort Gould's meaning.
Usually when you quote someone you quote the relevant material. Disliking
where they came from doesn't make them go away. His quotes are entirely
consistent with what I've read of him and is consistent with his reasoning
for coming up with Punctuated Equalibrium.
Preston Cloud & Martin F. Glaessner, "Ever since Darwin, the geologically
abrupt appearance and rapid diversification of early animal life have fascinated
biologist and students of Earth history alike....This interval, plus Early Cambrian,
was the time during which metazoan life diversified into nearly all of the major
phyla and most of the invertebrate classes and orders subsequently known."
Science, Aug.27, 1982
What do you think Cloud and Glaessner meant by "this interval"? They
clearly aren't talking about the Cambrian explosion, because they say
"plus Early Cambrian".
It's clear to me that they are talking about the abrupt timespan of
appearance and diversification of life, which includes the early Cambrian
period.
The Early Cambrian alone is about 25 million years long. Add some other
unspecified period to that and how abrupt is it?
Yes, according to everyone else that I've read. The words Cambrian Explosion
comes to mind.
I don't know what they mean, but most classes
don't come along until the Ordovician or later, and most orders not
until the late Paleozoic. Also note that they are talking here about
just those phyla with good fossil records.
That's your belief but that isn't what they said. There's no mention
of fossil record quality, but "all of the major phyla and most of the
invertebrate classes and orders subsequently known."
We don't know what they're talking about because the quote doesn't tell
us.
Yes it does.
"Ever since Darwin, the geologically abrupt appearance and rapid
diversification of early animal life have fascinated biologist and students
of Earth history alike..."
But I do know when, according to the fossil record, most
invertebrate classes and orders arose. And it's not in the Cambrian. I
can't find a single source on the web for this (though there are clues
for individual groups here and there). You might want to check out this
book: M. J. Benton (ed). 1993. The Fossil Record 2. Chapman & Hall, London.
1993? Ten year old stuff is too old but a 12 year old book will do? I'm
not buying into it since it contradicts everything I've read and I don't have the
time or opportunity to excavate fossils for myself.
RICHARD Monastersky, Earth Science Ed., Science News, "The remarkably
complex forms of animals we see today suddenly appeared. ...This moment,
right at the start of the Earth's Cambrian Period...marks the evolutionary
explosion that filled the seas with the earth's first complex creatures. ...‘This
is Genesis material,’ gushed one researcher. ...demonstrates that the large
animal phyla of today were present already in the early Cambrian and that
they were as distinct from each other as they are today...a menagerie of clam
cousins, sponges, segmented worms, and other invertevrates that would seem
vaguely familiar to any scuba diver." Discover, p.40, 4/93
You did this one before. I guess that was before the newest radiometric
dates showed that most of the Early Cambrian came before the Cambrian
explosion. And look at all the ellipses here. If you do this with the
bible, you can come up with stuff like "Luke...I am...your father."
Quote mining is bad practice, especially when you have to stitch
together sentence fragments.
That's not an honest response. If the biblical reference, is given, like the above,
the verse(s) can be referenced. Your claim is that they misrepresented the
author's intent by devious editing, as if the commments would take on a
different meaning with clarification. Even so the author was wrong anyway.
I see a pattern here that's clearer than the fossil record.
All I can say is read the actual articles, not the mined quotes.
Minimizing them by calling them mined quotes doesn't improve your case.
And
read some recent paleontology. There are genuine controversies in
research on the Cambrian explosion, but you haven't touched on any of
them yet.
A fossil fight would be an interesting read but the general consensus is
as that alot happened in a geologically short time span and it defies
the traditional evolution model.
It requires creative thinking to try to explain it, the controversies don't make
the problem less of a problem.