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Author Topic:   Does Chen's work pose a problem for ToE?
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 13 of 84 (290145)
02-24-2006 3:04 PM
Reply to: Message 1 by randman
02-24-2006 2:07 PM


Is this validation of longstanding Creationist/ID criticism in this arena, and what do EVCers think about the idea that the evolutionary time-scale is compressed from 50 million to 2-3 million, and that this is insufficient time to explain by random mutations and natural selection the explosion of life forms we see during that period.
I have been of the opinion that evolution isn't just random mutation and natural selection for some time. Other factors are likely to be found, or explored, such as epigenetics. Early life may always remain a mystery, it may be that a mechanism that existed then no longer exists, or that fecundity and selection were very high. A mystery it may forever remain.
The problem is, I've read this article before. I've not seen much else about it since it was written. It seems he is basically proposing 'Harmony' as another force in evolution. Have you any more information on this proposal? Does Chen have any evidence for his Harmony hypothesis?
When I first read this article my reaction was
quote:
Had a look at the page. It quotes Eric Davidson as saying "Neo-Darwinism is dead," but I can't find the original quote. Note however, he didn't say the Theory of Evolution. And also note that this is suspiciously similar to something Gould said 25 years ago: “the neo-Darwinism synthesis is effectively dead, despite its continued presence as textbook orthodoxy.” (Stephen Jay Gould, Is a New and General Theory of Evolution Emerging? 6 Paleobiology 119, 119-20 (1980)
I would like to see what kind of mathematics have been done to demonstrate that the mechanisms we know of at this time are insufficient.
As an aside, this topic has been addressed before, perhaps a read of Message 1 might be good for readers of this thread.

This message is a reply to:
 Message 1 by randman, posted 02-24-2006 2:07 PM randman has replied

Replies to this message:
 Message 15 by randman, posted 02-24-2006 5:27 PM Modulous has replied

  
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 26 of 84 (290181)
02-24-2006 5:45 PM
Reply to: Message 15 by randman
02-24-2006 5:27 PM


Re: random mutation and natural selection
But do not random mutation and natural selection consist of the bulk of evidentiary claims for ToE,
They are the biggest elements of evolutionary theory, and the easiest to describe. However, plenty of other mechanisms have been discussed on this board. I'm not au fait with them all, but things like horizontal transfer and epigenetics are among them as well as recombination.
and moreover, haven't evos (perhaps even yourself) argued that ToE can be falsified by whether natural selection and random mutation can account for macroevolution
Not that I'm aware of. If such an argument was used, I imagine it was a simplification.
or are all those claims that microevolution is macroevolution and really all the evidence you need just so much hot air?
I don't think the claim that microevolution is macroevolution holds particular water...I suspect that this argument is put forward as an illustration that the mechanisms are the same and there isn't a line between them.
I don't know which EvC debate you've been reading but that is certainly not the extent of the evidence for macroevolution. I have two threads open that discuss in some way the evidence.

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 Message 15 by randman, posted 02-24-2006 5:27 PM randman has replied

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 Message 30 by randman, posted 02-24-2006 5:53 PM Modulous has replied

  
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 33 of 84 (290189)
02-24-2006 6:00 PM
Reply to: Message 30 by randman
02-24-2006 5:53 PM


Re: random mutation and natural selection
But you suspect microevolution based on natural selection of mutations and variation cannot explain all the data, right?
I don't think those mechanisms explain all of evolutionary change, no.
It cannot explain the macroevolution of the Cambrian explosion, right?
I haven't a clue to be honest. However, see answer above.
Basicaly, if ToE cannot explain the Cambrian explosion, it is useless. Clearly, there is something else involved creating such an explosion of life.
If ToE cannot explain the Cambrian explosion it is far from useless. That's like saying Newton laws of motion cannot explain near light speed physics so its useless, despite it getting us to the moon and back.
I suspect you are under the impression that the ToE is only RM/NS. May I assure you that epigenetics, horizontal transfer etc are all part of it. I do suspect that there are more evolutionary mechanisms awaiting discovery and/or refinement, as do evolutionary biologists conducting research.

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Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 39 of 84 (290195)
02-24-2006 6:11 PM
Reply to: Message 37 by crashfrog
02-24-2006 6:06 PM


Re: what are you saying?
None of the life-forms that you would probably recognize as "major" are present in Cambrian fossils.
Rand was talking about phyla. Here is a list of the major phyla
abe: I see rand previously said 'major life forms'. My mistake...and rand's.
This message has been edited by Modulous, Fri, 24-February-2006 11:13 PM

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Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 50 of 84 (290218)
02-24-2006 7:51 PM
Reply to: Message 46 by jar
02-24-2006 7:32 PM


50 million years
quote:
The dearth of earlier
fossils made it impossible to test ideas
about what triggered the “explosion” or
even to say for sure whether it was real
or merely seemed so because earlier animals
left few detectable traces of themselves.
But research over the past half a
dozen years”including ours in Guizhou
Province”has changed the long-held
view, suggesting that complex animals
arose at least 50 million years earlier
than the Cambrian explosion.
and
quote:
Yet as Charles Marshall of Harvard
University has argued and as our fi ndings support, the genetic
tool kit and pattern-forming mechanisms characteristic of
bilaterians had likely evolved by the time of the Cambrian
explosion. Thus, the “explosion” of animal types was more
accurately the exploitation of newly present conditions by
animals that had already evolved the genetic tools to take
advantage of these novel habitats rather than a fundamental
change in the genetic makeup of the animals.
So there we have it, it seems there was no explosion. It looks like it was already evolved organisms suddenly finding themselves in a niche that was to their advantage (by virtue of creating it for themselves) and so they became the dominant life forms. Kind of like a biological feedback effect in a way.
Very interesting stuff, thanks jar.

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 Message 46 by jar, posted 02-24-2006 7:32 PM jar has not replied

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 Message 56 by randman, posted 02-25-2006 12:30 PM Modulous has replied

  
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 58 of 84 (290339)
02-25-2006 1:17 PM
Reply to: Message 56 by randman
02-25-2006 12:30 PM


Re: 50 million years
Modulous, except these guys in the OP say the fact we found complex or whatever you want to call them creatures earlier, compresses the time period for them to have evolved even further
But work subsequent to the OP falsifies that. They previously thought that the evolution of these organisms started at x years, and the diversity was seen at x + 2 million years. Thus the compression. However, the evolution of these organisms started that at x - 50 million years. So the diversity of life came about not in 2 million years but instead 52 million years. No compression at all.
Can one of you guys address what Chen and his colleague are saying?
Sure. Which piece of work? Their earlier work (from the OP), or the work that that superceded it (brought up by jar)? I've addressed both, so tell me which one you mean, and we'll talk about it.
This message has been edited by Modulous, Sat, 25-February-2006 06:18 PM

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 Message 56 by randman, posted 02-25-2006 12:30 PM randman has replied

Replies to this message:
 Message 59 by randman, posted 02-25-2006 1:36 PM Modulous has replied

  
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 61 of 84 (290395)
02-25-2006 2:39 PM
Reply to: Message 59 by randman
02-25-2006 1:36 PM


Re: 50 million years
That still doesn't explain it, modulous. Maybe you can elaborate. What they say is they were looking for more primitive organisms and instead found more advanced, and finding more advanced earlier, in their view, refutes current evo mechanisms.
I don't see that. I see the problem being the time scale. The earlier work compressed it, the later expanded it (effectively shifting it to an earlier date).
So why wouldn't finding even more advanced organisms even earlier just make their point all the more stronger?
Because it means that the diversity had longer than 3 million years to happen within.
Also, did you catch they are making the same point I have been making onthe fossil record. They are saying that the current evo claims of fossil rarity are wrong; that the fossil record is a lot more complete and does show soft body creatures than what previous evo models claimed, and armed with such awareness of what the fossil record shows, they made the bold statements they make. Basically, they are saying the fossil record contradicts current evo models, and so "no evolutionary theory can explain this...."
I caught some of their opinions on the matter. I don't see anything about the same kind of fossil rarity that you have been claiming. It seems that if you look hard enough you actually find the Cambrian explosion wasn't an explosion, but an exploitation by already existing organisms.
Now, I am open to any suggestion that later finds have changed their stance, or should have changed their stance....I just have not seen it yet in what you guys have posted....in fact, it seems pretty clear to me that these guys are evolutionists themselves, and are very open to accepting evolutionist mechanisms if that is reasonable. They have just come to the conclusion that evo mechanisms are not reasonable, at least not the ones put forth so far.
As I said earlier in this thread...their statements are very old, and they are only referenced in only one source, a newspaper article. I asked you if you had any more up to date statements made by them, it would be helpful to get more context and depth to what they are actually saying.
All I know right now is that Dr Chen is proposing another mechanism on top of what we already have, something referred to as 'harmony'. I don't know if he still holds to that view, and I don't know if there has been any work on the hypothesis since. Do you have anything?

I've found some more recent information (2004)
BBC writes:
Professor Chen, from Nanjing University, and his team write in Science: "The organisation of these fossils, taken together with their provenance, indicates that the genetic toolkit and pattern formation mechanisms required for bilaterian development had already evolved by Doushantuo times, long before the Cambrian."
However some scientists are sceptical of the claims, suspecting that what have been characterised as fossils may in fact be natural mineral formations.
Stefan Bengtson, from the Swedish Museum of Natural History in Stockholm, said: "These may well have started out as fossils, but we can't say much about their morphology."
He told Science magazine the presumed tissue layers may be just thin, banded mineral crusts.
Traces of simple bacteria-like organisms in the fossil record date back more than three billion years.
and
New Scientist writes:
Guy Narbonne of Queen's University in Kingston, Ontario, Canada, is impressed by the fossils.
"What I find most intriguing is how closely it matches the most recent predictions of molecular and developmental biology," he told New Scientist. "And what a far cry from the predictions of biology even a few years ago," which did not envisage the first bilateral animals being microscopic, soft-bodied sea-floor dwellers.
However, some remain sceptical. Stefan Bengston of the Swedish Museum of Natural History believes the internal structures are in fact minerals deposited after death inside simpler microfossils.
This message has been edited by Modulous, Sat, 25-February-2006 07:50 PM

This message is a reply to:
 Message 59 by randman, posted 02-25-2006 1:36 PM randman has replied

Replies to this message:
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 Message 63 by randman, posted 02-25-2006 3:59 PM Modulous has replied

  
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 64 of 84 (290407)
02-25-2006 4:17 PM
Reply to: Message 63 by randman
02-25-2006 3:59 PM


compression
Modulous, what you are missing is that they show that soft body creatures fossilized quite well, and the further back they go, instead of finding precursors to the phyla, they find the same stuff. That's why finding phyla from 543 million years ago is a compression of the Cambrian explosion not an extension of it.
I'm not missing that at all. These complex organisms have been found in layers 600 million years old, so the time scale isn't compressed. Interestingly the molecular evidence predicted this. Allow me to quote from jar's article:
One huge problem with fi nding such
animals is that they did not have hard
skeletons that would mineralize and become
fossils. So we must rely on uncovering
the rare deposit that, because of
the type of rock and the chemical processes
involved, preserves intricate details
of the remains. These deposits are
called lagersttten, a German word that
means “lode places” or “mother lode.”
A lagersttte that preserves soft tissue is
a spectacular rarity; we know of only
several dozen scattered over the earth.
So, it goes like this,
We have things such as Vernanimalcula showing up 600 million years ago, 555 million years ago we get Kimberella and then 542 million years ago we find Anomalocaris.
biological complexity of the
kind seen in Vernanimalcula implies a
period of evolution that transpired long
before the 580-million- to 600-millionyear-
old world in which the tiny animal
lived. After all, it could not have gained
that degree of symmetry and complexity
all at once. We now need to fi nd older
lagersttten that might hold clues to
its ancestors.
...
We have a good deal left to learn,
but the work so far has given substance
to our earlier suspicion that complex
animals have a much deeper root in time,
suggesting that the Cambrian was less of
an explosion and more of a fl owering of
animal life.
This message has been edited by Modulous, Sat, 25-February-2006 09:28 PM

This message is a reply to:
 Message 63 by randman, posted 02-25-2006 3:59 PM randman has replied

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Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 67 of 84 (290416)
02-25-2006 4:53 PM
Reply to: Message 66 by randman
02-25-2006 4:48 PM


Re: compression
600 million? That makes it even worse for the evo argument.
Not at all. It means that there is 60 million years of evolution between early bilaterian life and the Cambrian period. We do not have a good fossil record of life before this (due to the rarity of the rock type required), so we do not know how much evolution happened between the start of life and the start of bilaterian life. We still have three billion years of evolution unaccounted for.
If you'd like to explain why it is worse for the evo argument, might I suggest presenting your argument.

This message is a reply to:
 Message 66 by randman, posted 02-25-2006 4:48 PM randman has replied

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 Message 68 by randman, posted 02-25-2006 6:28 PM Modulous has replied

  
Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 69 of 84 (290446)
02-25-2006 6:41 PM
Reply to: Message 68 by randman
02-25-2006 6:28 PM


Re: a small recap
I agree upon further reading that finding older bilaterals is helpful to mainstream evolutionist theories here but still hardly definitive.
Nothing is definitive, that applies double at the area we are looking at.
Once again, we reallly should be seeing massive numbers and we don't.
Why should we see massive numbers? The rock type we need to look in is very rare...only a few dozen exist, and I found only two that cover the area we are discussing.
I think from the quotes above it is clear that the Asians are more open-minded and believe that different mechanisms must be invoked, and they are willing to consider ID as well, as a potential scientific possibility.
Asia is a massive continent. The people we are discussing are Chinese. I'm not sure we can say easily that the Chinese are more open minded or not. I've said before, I'm entirely open to their being other mechanisms involved in evolution.

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Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 79 of 84 (290835)
02-27-2006 9:45 AM
Reply to: Message 68 by randman
02-25-2006 6:28 PM


incidentally
The article you linked to was once again out of date. It is dated July 24, 2000.
Fred Heeren writes:
But Chen and Li were disappointed not to have found any bilaterians; they hadn’t found a truly viable ancestor for any of the new animals appearing in the Cambrian explosion.
Chen and Li were disappointed, but 4 years later they found them.
Moreover, by finding sponges and their microscopically tiny embryos in the Precambrian, they inadvertently rebutted Westerner wisdom. Charles Darwin himself had said that in order for his theory to work, the ancestors of the Cambrian animals must have been evolving for long ages prior to their Cambrian appearance.
Which is what they found 4 years later...so does this logically unrebut Westerner wisdom?
Western scientists would have none of it. “It doesn’t matter if you find it or not!” declared German biologist Dieter Walossek, rallying his Western colleagues around him. “It’s there! It’s by law! All of the major taxa should have been there in the Precambrian, whether proved or not!”
As arrogant as Walossek comes off in this quote, it turns out he has a point. The bilaterals were there.
Just thought I'd throw that out there in case anybody was taken in by the article. For the lurkers: A better article, a more up to date article, can be found in the article jar referenced.
This message has been edited by Modulous, Mon, 27-February-2006 02:52 PM

This message is a reply to:
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 Message 80 by randman, posted 02-27-2006 12:09 PM Modulous has replied
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Modulous
Member (Idle past 101 days)
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 82 of 84 (290884)
02-27-2006 1:11 PM
Reply to: Message 80 by randman
02-27-2006 12:09 PM


of dogmatism and conservatism
their assessment of western scientists is still very telling when it comes to evolution
As PaulK mentioned in Message 9 - science is conservative. I appreciate this can lead to a dogmatic appearance, and it would be nice to see a more liberal approach. However, the liberal approach is known for allowing pseudoscience to creep in, so I'm inclined to stick with the flaws of conservatism rather than the flaws of liberalism in the case of science.
I like the fact that it takes a lot of work to change the minds of scientists, it gives me confidence that the theories they hold to have been rigorously examined and criticised before becoming 'dogma'. Before his 2004 discoveries Chen was proposing that the mechanisms we know of evolution were not enough (he proposed Harmony as another principle, but I never saw any details about what this actually is). He was basing this conclusion on an absense of evidence. Other scientists were rightly skeptical. A few years down the line and Chen's absence of evidence seemed to vanish.
I am also unwilling to make hasty generalizations about 1.3 billion people based on a sample size of less than a dozen hand picked by an intelligent design journalist.
abe: oh! And enjoy your vacation!
This message has been edited by Modulous, Mon, 27-February-2006 06:21 PM

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