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  Topic: Professor Emertitus John A.Davison's view of PT, Some thoughts from JAD< Next Oldest | Next Newest >  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 28 2006,04:32   

Quote

Those subnormal morons over at After The Bar Closes are nothing but a bunch of gossiping barnyard hens. If they had an ounce of spine they would be after me instead of DaveScot. He is the moderator and he can do whatever he pleases with lightweights like the Panda's Thumb crowd. They remind me of Harry S. Truman's description of an adversary he once had:

"He is a living miracle with neither brains nor guts."

Amen Harry baby, my kind of guy!

How do you like them rotating vertical spindles? Climb on and enjoy yourself. It's later than you think.


(from his blog)

  
stevestory



Posts: 10127
Joined: Oct. 2005

(Permalink) Posted: Jan. 28 2006,04:43   

Quote
Those subnormal morons over at After The Bar Closes are nothing but a bunch of gossiping barnyard hens.


I think of myself more as Statler or Waldorf, those two old muppets who sat up in the balcony mocking the show.

Does Intelligent Design deserve any other treatment?



“I like Dembski's next book!"
"It hasn't been published yet."
“That's what I like about it!"

   
Mr_Christopher



Posts: 1238
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,05:27   

Quote (stevestory @ Jan. 28 2006,10:43)
Quote
Those subnormal morons over at After The Bar Closes are nothing but a bunch of gossiping barnyard hens.


I think of myself more as Statler or Waldorf, those two old muppets who sat up in the balcony mocking the show.

Does Intelligent Design deserve any other treatment?



“I like Dembski's next book!"
"It hasn't been published yet."
“That's what I like about it!"

Brilliant!


Good one, Steve.

--------------
Uncommon Descent is a moral cesspool, a festering intellectual ghetto that intoxicates and degrades its inhabitants - Stephen Matheson

  
stevestory



Posts: 10127
Joined: Oct. 2005

(Permalink) Posted: Jan. 28 2006,05:43   

Man, there are some idiots over there at Uncommon Pissant:

Quote
Not only is Dr. Davison an intellectual giant, he is also a giant of intellectual honesty. Truly a rare combination.

Comment by dougmoran — January 28, 2006 @ 10:46 am

   
Caledonian



Posts: 48
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,05:51   

Let's be honest.  Creationists' blogs share one feature with rationalists' blogs:  they're all about self-congratulation.

Rationalists have more than self-congratulation.  That's the essential difference.

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 28 2006,05:56   

SteveS

You don't think Dougmoran was being ironic?

  
stevestory



Posts: 10127
Joined: Oct. 2005

(Permalink) Posted: Jan. 28 2006,06:33   

I should hope so. But with creationists I can never tell. This classic is perfectly serious:


   
Arden Chatfield



Posts: 6657
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,06:34   

Quote
Those subnormal morons over at After The Bar Closes are nothing but a bunch of gossiping barnyard hens. If they had an ounce of spine they would be after me instead of DaveScot


Sounds to me like Old Man Davison is mostly just jealous of all the attention Dave is getting...

Hey! Let's ask him what happened in the mid-1980's that made him switch from mainstream biology research to anti-evolution crankery! That subject seems to make him very testy...

--------------
"Rich is just mad because he thought all titties had fur on them until last week when a shorn transvestite ruined his childhood dreams by jumping out of a spider man cake and man boobing him in the face lips." - Erasmus

  
Arden Chatfield



Posts: 6657
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,06:39   

Quote (stevestory @ Jan. 28 2006,12:33)
I should hope so. But with creationists I can never tell. This classic is perfectly serious:


Don't laugh, I'd bet Heddle and Carol both literally believe that...

--------------
"Rich is just mad because he thought all titties had fur on them until last week when a shorn transvestite ruined his childhood dreams by jumping out of a spider man cake and man boobing him in the face lips." - Erasmus

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 28 2006,07:12   

According to his CV

Publications:

1954.   Muscle apyrase as a function of temperature in the cockroach,
       crayfish and minnow.  Archives of Biochemistry and Biophysics,
       48: 485-486.  With A.G. Richards.

1955.   Body weight, cell surface, and metabolic rate in anuran amphibia.
       Biological Bulletin, 109: 407-419.  Ph.D. thesis.

Then nothing except his his semi-meotic nonsense.

1956.   An analysis of cell growth and metabolism in the crayfish
       (Procambarus alleni).  Biological Bulletin, 110: 264-273.

1957.   A fluid drop model of the elliptical red blood cell.
       Experientia, 13: 472-477.

1958.   Studies on the form of the amphibian red cell.
       Anatomical Record, 132: 426-427.  Abstract.

1958.   Organ metabolism in mature mammals as the product of allometric
       mass and rate.  American Naturalist, 92: 105-110.

1959.   Studies on the form of the amphibian red blood cell.
       Biological Bulletin, 116: 397-405.

1959.   Determination of form of the amphibian red blood cell.
       The Physiologist 2.  Abstract.

1961.   A study of spotting patterns in the leopard frog.
       1. Effect of gene dosage.  Journal of Heredity, 52: 301-304.

1963.   Gene action mechanisms in the determination of color and pattern
       in the frog (Rana pipiens).  Science, 141: 648-649.

1964.   Animal organization as a problem in cell form.  In: J.R. Gregg
       & F.T.C. Harris (eds.), Form and Strategy in Science: Studies
       Dedicated to Joseph Henry Woodger on the Occasion of His
       Seventieth Birthday.  Dordrecht, Holland: D. Reidel.

1964.   A study of spotting patterns in the leopard frog.
       3. Environmental control of genic expression.
       Journal of Heredity, 55: 47-56.

1964.   Spotting variation in the leopard frog: a test for the
       genetic basis in the Rana pipiens "burnsi" variant.
       Journal of Heredity, 55: 234-241.  With L.W. Browder.

1966.   Chimeric and ex-parabiotic frogs (Rana pipiens):
       Specificity of tolerance.  Science, 152: 1250-1253.

1967.   Evidence for cell transformation following embryonic
       transplantation in the frog.  Journal of General
       Physiology, 50: 1096.

1969.   Activation of the ephippial egg in Daphnia pulex.
       Journal of General Physiology, 53: 562-575.

1973.   Population growth in planaria: Dugesia tigrina (Gerard):
       Regulation by the absolute number in the population.
       Journal of General Physiology, 61: 767-785.

1976.   Hydra hymanae: Regulation of the life cycle by time
       and temperature.  Science, 194: 618-620.

Then nothing except his semi-meiotic stuff.

  
Arden Chatfield



Posts: 6657
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,07:21   

To me, the most noticeable jump seems to happen after 1987:

1969.   Activation of the ephippial egg in Daphnia pulex.
       Journal of General Physiology, 53: 562-575.

1973.   Population growth in planaria: Dugesia tigrina (Gerard):
       Regulation by the absolute number in the population.
       Journal of General Physiology, 61: 767-785.

1976.   Hydra hymanae: Regulation of the life cycle by time
       and temperature.  Science, 194: 618-620.

1984.   Semi-meiosis as an evolutionary mechanism.
       Journal of Theoretical Biology, 111: 725-735.

1987.   Semi-meiosis and evolution: a response.
       Journal of Theoretical Biology, 126: 379.

then after this, the slide starts:

1993.   The blind alley: its significance for evolutionary theory.
       Rivista di Biologia (Biology Forum), 86-1: 101-110.
       http://www.uvm.edu/~jdavison/evolution.html

1998.   Evolution as a self-limiting process.
       Rivista di Biologia (Biology Forum), 91-2: 199-220.
       http://www.uvm.edu/~jdavison/dpaper.html

1999.   An Evolutionary Manifesto: A New Hypothesis for Organic Change.
       Offered for publication.
       http://www.uvm.edu/~jdavison/davison-manifesto.html


...it's not a good sign when your titles include the word 'manifesto' in them.

--------------
"Rich is just mad because he thought all titties had fur on them until last week when a shorn transvestite ruined his childhood dreams by jumping out of a spider man cake and man boobing him in the face lips." - Erasmus

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 28 2006,08:13   

Quote
Our in house pet masochist, Alan Fox, has done exactly what I wanted him to do. Look at the wonderful responses he has been able to evoke there at "After The Pub Shuts Down." I am especially grateful that the #### fool listed my publications at least through the seventies which include three single authored papers in Science one of the most widely read and respected science journals in the world. Who at Panda's Thumb can claim as much I wonder? Who at Panda's Thumb has published anything of note anywhere? It is pretty hard to tell as they hide behind their cowardly aliases while they spew thir mindless viriol, glued to their bar stools congratulating each other over their knowledge of an event that has never been witnessed.

Thank you once again Alan Fox for proving once more to be my greatest ally as well as by, in so doing, proving also that your IQ must be in the room temperature range.

It is hard to believe isn't it?

I love it so!

"Davison is the Darwinians'worst nightmare."
Terry Trainor

Alan Fox just proved it.

"Since God found it necessary to limit man's intelligence, why didn't he also limit his stupidity?
Konrad Adenauer

Beats me Konrad. Ask Alan Fox. He knows everything.

11:15 AM


He's noticed.

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 28 2006,08:16   

I haven't read Davison's "manifesto", or any of his "Rivista" expositions. And, considering the portrait of himself he paints in his internet communications, it's not very high on my list of reading priorities. (Somewhere between the  Harlequin romances and the complete works of Rush Limbaugh.) But there are some themes in his rants I sympathize with (sort of).

"Evolution is over". Well, no. Obviously evolution is still going on. But the specialization of the more complex multicellular animals does constitute something of a "blind alley". The pre-Cambrian precursors  by virtue of their simplicity, had a kind of evolutionary pluripotentiality that modern cockroaches, humans and starfish don't. For instance, no matter what combination of natural selection forces are brought to bear, I'm pretty confident that no descendents of humans will evolve an exoskeleton. And in this sense, there is a meaningful analogy to be drawn with ontogeny: a lymphocyte, having made a series of epigenetic commitments in the course of development, does not have the option of spawning neurons.

The "Cambrian explosion" was possible because, at that time, there was a huge range of niches for which there was no biological competition. In expanding into those niches, each lineage of animal life made multiple, essentially irreversible, commitments. And nowadays, the available niches are pretty well spoken for. So a second "Cambrian explosion" will have to await some huge cataclysm clearing the decks of the entrenched forms.

So, I side with Davison against the uniformitarianism commonly (though I'm not sure completely accurately) associated with Darwin. And I see some merit in the analogy between evolution and ontogeny (though Davison seems to think it's more than an analogy). And, at least for the meantime, evolution of modern animal forms is largely i-dotting and t-crossing relative to the radical developments associated with the past. But what any of this has to do with "intelligent design" is beyond me.

--------------
Must... not... scratch... mosquito bite.

  
Arden Chatfield



Posts: 6657
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,08:21   

Quote (Alan Fox @ Jan. 28 2006,14:13)
Quote
Our in house pet masochist, Alan Fox, has done exactly what I wanted him to do. Look at the wonderful responses he has been able to evoke there at "After The Pub Shuts Down." I am especially grateful that the #### fool listed my publications at least through the seventies which include three single authored papers in Science one of the most widely read and respected science journals in the world. Who at Panda's Thumb can claim as much I wonder? Who at Panda's Thumb has published anything of note anywhere? It is pretty hard to tell as they hide behind their cowardly aliases while they spew thir mindless viriol, glued to their bar stools congratulating each other over their knowledge of an event that has never been witnessed.

Thank you once again Alan Fox for proving once more to be my greatest ally as well as by, in so doing, proving also that your IQ must be in the room temperature range.

It is hard to believe isn't it?

I love it so!

"Davison is the Darwinians'worst nightmare."
Terry Trainor

Alan Fox just proved it.

"Since God found it necessary to limit man's intelligence, why didn't he also limit his stupidity?
Konrad Adenauer

Beats me Konrad. Ask Alan Fox. He knows everything.

11:15 AM

Davison sounds much happier now.

--------------
"Rich is just mad because he thought all titties had fur on them until last week when a shorn transvestite ruined his childhood dreams by jumping out of a spider man cake and man boobing him in the face lips." - Erasmus

  
O. Johnson



Posts: 14
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,08:27   

Interesting misspelling of emertitus [sic] on the subject line.

Freudian slip?

Stupidity?

You be the judge.  I'm going with what's behind door number 2.

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 28 2006,09:00   

"emertitus", "Freudian slip"? I don't get it.

--------------
Must... not... scratch... mosquito bite.

  
Stephen Elliott



Posts: 1754
Joined: Oct. 2005

(Permalink) Posted: Jan. 28 2006,09:53   

JAD is great. I want him back.

How do you like those fried green tomatoes?

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 28 2006,10:20   

Russell said

Quote
And, at least for the meantime, evolution of modern animal forms is largely i-dotting and t-crossing relative to the radical developments associated with the past.


Till the next big meteor strike, maybe.

I agree that John does seem to have some challenging ideas, but it seems impossible to draw him into debate. He does not respond well to criticism or queries. You either accept what he is saying as a good student should, or you are out of his lecture hall. He has said he has a recurring nightmare of lecturing to a hall empty of students and I suspect he still craves the respect that his former position gave him.

(Reminder to self; always spellcheck before posting.)

  
The Ghost of Paley



Posts: 1703
Joined: Oct. 2005

(Permalink) Posted: Jan. 28 2006,11:21   

"IQ must be in the room temperature range"?

Hey, he's stealing my lines!  :D

--------------
Dey can't 'andle my riddim.

  
Caledonian



Posts: 48
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,12:09   

Even if there were a truly massive extinction event, are there any sufficiently unspecialized lifeforms that could give rise to another Cambrian Explosion?  What's left?

  
jeannot



Posts: 1200
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,12:22   

:09-->
Quote (Caledonian @ Jan. 28 2006,18:09)
Even if there were a truly massive extinction event, are there any sufficiently unspecialized lifeforms that could give rise to another Cambrian Explosion?  What's left?

I don't think this is related to specialization, which mainly refers to the ecological niche. Humans are not so specialized after all. ;)

Ecological specialization is often seen as a dead-end, because of the competition between species (niche assembly). It's no longer the case if this competition (including predation, etc) disappears.
For example, the modern sponges could be seen nowadays as ecologically "specialized" species (which is subjective). If the other animals dy in a cataclysm, I'm pretty sure that the absence of predators/competitors would allow the modern sponges to explore new niches and produce new body plants, as their ancestors did before the cambrian.


(I hope my English is good enough)

  
O. Johnson



Posts: 14
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,14:06   

I've been following this guy Davison for quite some time and I have to tell you he is no dummy. He has a mastery of the classical evolutionary literature. Quite frankly I believe he has put forth a darn convincing scenario that evolution is finished and probably will not ever resume. He is also convinced that sexual reproduction can't perform even speciation at least in the lab.He keeps putting out challenges and nobody responds to him. I am no expert but I have the feeling he is onto something pretty darn revolutionary. From what he said over at his blog I doubt if he would return to Panda's Thumb even if you invited him. He seems pretty hostile to me. I think it would darn interesting if he did. Hells bells - why not ask him?

  
Arden Chatfield



Posts: 6657
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,14:10   

Quote (O. Johnson @ Jan. 28 2006,20:06)
I've been following this guy Davison for quite some time and I have to tell you he is no dummy. He has a mastery of the classical evolutionary literature. Quite frankly I believe he has put forth a darn convincing scenario that evolution is finished and probably will not ever resume. He is also convinced that sexual reproduction can't perform even speciation at least in the lab.He keeps putting out challenges and nobody responds to him. I am no expert but I have the feeling he is onto something pretty darn revolutionary. From what he said over at his blog I doubt if he would return to Panda's Thumb even if you invited him. He seems pretty hostile to me. I think it would darn interesting if he did. Hells bells - why not ask him?

How do you like them little green apples, John?

--------------
"Rich is just mad because he thought all titties had fur on them until last week when a shorn transvestite ruined his childhood dreams by jumping out of a spider man cake and man boobing him in the face lips." - Erasmus

  
O. Johnson



Posts: 14
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,15:00   

Arden Chatfield

That is a lousy way to greet a new participant here. Why don't you just ban me if that is your attitude. Frankly I don't think you know what you are talking about and I don't care either. I have to agree with Davison about the quality of the dialogue here. He is currently holding forth at brainstorms and Uncommon Descent anyway. I doubt if he needs this forum. I sure don't.

Sincerely

Otto Johnson

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 28 2006,15:22   

O. Johnson doesn't mind Davison's mouth-foaming rants and nonstop insults, but he finds Arden Chatfield's quote of Davison offensive? Go figure.

--------------
Must... not... scratch... mosquito bite.

  
Wesley R. Elsberry



Posts: 4807
Joined: May 2002

(Permalink) Posted: Jan. 28 2006,20:53   

From the TOA Feedback for May, 2000:

Quote

I recently read a work by John A. Davison, Ph.D., professor of biology at the University of Vermont entitled "AN EVOLUTIONARY MANIFESTO: A NEW HYPOTHESIS FOR ORGANIC CHANGE." In this work he challenges the traditional Darwinian notion that natural selection is the mechanism by which macroevolution occurs in sexually reproducing organisms. He instead proposes the "semi-meiotic hypothesis" to explain speciation/macroevolution. Essentially, he proposes that "evolution" occurs at the level of the chromosome, not the gene. He does not dispute that changes in gene frequency occur within a species (e.g., peppered moths), but at the same time he does not believe that this same mechanism (i.e., natural selection) accounts for macroevolution. Is this hypothesis plausible?


It is commonly held that speciation processes are largely, if not totally, independent of natural selection. In this Davison is simply part of the crowd. I recently heard a talk given by Kurt Benirschke which attributed most speciational changes in mammals to chromosomal fusion events. So, when properly delimited, saying that much of the speciation we see in mammals (or perhaps even vertebrate animals) is due to some sort of chromosomal rearrangement is plausible, since that is what the karyotype data seems to show.

In looking at Davison's "manifesto", I personally found some reasons for concern about the validity of various points. Since I have long heard similar claims about chromosomal rearrangement and speciation, the claimed novelty of Davison's hypothesis seems more hype than substance. There seems to be a lot of textual interpretation within the work which purports significance in the real world. Quotations seem to be treated much as "proof-texts" are in apologetics. Many of his claims about what "Darwinism" must entail are arguable, and some are simply wrong. I think that in Davison's particular case, he might hold a correct position with regard to speciation events being often due to chromosomal rearrangement without having grounded his other corollaries in much besides his personal prejudices, buttressed with some quotes from others having congruent prejudices.

In general, when evaluating non-mainstream claims, it is good to keep one's skepticism sharp. The taint of self-aggrandizement is a clue that should not be overlooked. Something of a field guide for such behavior in physics can be applied with a few changes to biological topics.

--------------
"You can't teach an old dogma new tricks." - Dorothy Parker

    
jeannot



Posts: 1200
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,22:43   

Quote (O. Johnson @ Jan. 28 2006,20<!--emo&:0)
I've been following this guy Davison for quite some time and I have to tell you he is no dummy. He has a mastery of the classical evolutionary literature. Quite frankly I believe he has put forth a darn convincing scenario that evolution is finished and probably will not ever resume. He is also convinced that sexual reproduction can't perform even speciation at least in the lab.He keeps putting out challenges and nobody responds to him. I am no expert but I have the feeling he is onto something pretty darn revolutionary. From what he said over at his blog I doubt if he would return to Panda's Thumb even if you invited him. He seems pretty hostile to me. I think it would darn interesting if he did. Hells bells - why not ask him?

"Evolution is finished"
What about speciation events and natural selection currently observed in the wild? What about artificial selection in the lab or in the farm?
What about you're children being slightly different from you? Even this is evolution.
If he thinks that evolution is just the rise of new body plans, by other mechanisms than mutations and selection (+ genetic drift), then he is missing something.
And what's this argument anyway? Evolution is finished, so now the Great Designer is in charge? Does Mr. Davison support ID?

"...and probably will not resume"
Did Mr. Davison calculate some probability?

"Sexual reproduction can't perform speciation"
Is this Davison's argument? I doubt it because this is just nonsense. Species can only be defined via sexual reproduction. There is no concept of speciation without sexual reproduction. And I like the "at least in the lab" part that clearly demonstrates that this process is not possible in the wild. Anyway this is wrong since species of Drosophila have been separated from single populations in lab conditions, and a few years. Also, many plant species are produced via hybridizing (even in the lab).

  
jeannot



Posts: 1200
Joined: Jan. 2006

(Permalink) Posted: Jan. 28 2006,22:56   

Quote (Wesley R. Elsberry @ Jan. 29 2006,02:53)
It is commonly held that speciation processes are largely, if not totally, independent of natural selection.

This not commonly held.
Speciation often seems independent of natural selection, yes ; but selection can also boost the process. You can search for "ecological speciation", (a concept pioneered by Dolph Schluter) or "sympatric speciation in cychlids fishes" for example.

  
Mr_Christopher



Posts: 1238
Joined: Jan. 2006

(Permalink) Posted: Jan. 29 2006,03:18   

Quote (O. Johnson @ Jan. 28 2006,21:00)
Arden Chatfield

That is a lousy way to greet a new participant here. Why don't you just ban me if that is your attitude. Frankly I don't think you know what you are talking about and I don't care either. I have to agree with Davison about the quality of the dialogue here. He is currently holding forth at brainstorms and Uncommon Descent anyway. I doubt if he needs this forum. I sure don't.

Sincerely

Otto Johnson

Mr Johnson, I don't think they ban people here for whining like a spoiled little baby so I don't think you have anything to worry about.

Cheers and welcome to the forum!

--------------
Uncommon Descent is a moral cesspool, a festering intellectual ghetto that intoxicates and degrades its inhabitants - Stephen Matheson

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 29 2006,03:29   

Mr Christopher

To avoid you giving more offence, you should be aware that it is Dr. Johnson. (No, not that one, he's dead.) This is Dr. Otto Johnson M.D., father of Dr Johnson (no, not that one) M. D.

So show a little more respect, please.

  
O. Johnson



Posts: 14
Joined: Jan. 2006

(Permalink) Posted: Jan. 29 2006,03:31   

Kirk to Enterprise.  

Beam me up, Scotty.  There's no intelligent life here.  I found a bleeding arse that read Davison's paper but doesn't know meiosis from falcon droppings and I found a moron that didn't read the paper but claims to refute it.  

Kirk Out.

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 29 2006,03:36   

Bye John

  
Caledonian



Posts: 48
Joined: Jan. 2006

(Permalink) Posted: Jan. 29 2006,03:43   

Quote
I don't think this is related to specialization, which mainly refers to the ecological niche. Humans are not so specialized after all.

 I'm talking about the specializations that give rise to phyla - having skeletons, having diversified tissues, having exoskeletons, bilateral symmetry, etc.  My understanding (which may be incorrect) is that once certain features are developed by organisms, they can no longer follow a different "pathway", since the changes necessary to remove major features are so large that they're essentially impossible.

I don't think that mammals could ever lose their skeletons and develop exoskeletons, regardless of the niches they might expand into.  The process of evolving into mammals from less differentiated organisms is irreversible.

  
Alan Fox



Posts: 1391
Joined: Aug. 2005

(Permalink) Posted: Jan. 29 2006,04:16   

I'm sure that is the generally accepted view, Caledonian. Which is why JAD's assertion that evolution only takes a species to eventual extinction may have a ring of truth. Once a species has found its niche, rapid environmental change will leave it "high and dry" and less developed species can take over the territory.

  
Caledonian



Posts: 48
Joined: Jan. 2006

(Permalink) Posted: Jan. 29 2006,04:32   

It's not a "specialization" as such, because vertebrates (for example) can still fit into many niches - it's not an adaptation to any particular environment.

That said, are there any undifferentiated organisms remaining that could give rise to a diverse set of body plans in the event of a truly massive extinction?  Or have all extant organisms committed themselves by this point?

  
Russell



Posts: 1082
Joined: April 2005

(Permalink) Posted: Jan. 29 2006,04:51   

I may have muddied the waters with my use of the word "specialization". I didn't mean in the relatively narrow sense of adaptation to a niche. I meant the series of commitments that are made in the course of the evolution of a highly complex multicellular animal. A mammal doesn't have the pluripotential options that a single celled organism has. If a cataclysm of unprecedented proportions wipes out 99.99+% of all life, I predict that whatever rises from the ashes will be descended from the relatively simple forms, not from us. But until a really huge cataclysm happens, really radical innovations are unlikely because they would be at a disadvantage relative to those of us who have had millions of years of honing.

"Irreducible complexity", after all, has to evolve, and a truly radical innovation would have to be babied along for thousands/millions of generations in a relatively non-competitive environment in order to accumulate the layers of interdependent systems that (for reasons, again, that escape me) Behe thinks constitute an argument against evolution.

--------------
Must... not... scratch... mosquito bite.

  
jeannot



Posts: 1200
Joined: Jan. 2006

(Permalink) Posted: Jan. 29 2006,06:41   

Quote (Caledonian @ Jan. 29 2006,09:43)
 I'm talking about the specializations that give rise to phyla - having skeletons, having diversified tissues, having exoskeletons, bilateral symmetry, etc.  My understanding (which may be incorrect) is that once certain features are developed by organisms, they can no longer follow a different "pathway", since the changes necessary to remove major features are so large that they're essentially impossible.

I don't think that mammals could ever lose their skeletons and develop exoskeletons, regardless of the niches they might expand into.  The process of evolving into mammals from less differentiated organisms is irreversible.

Fine, but your conception is not referred to as "specialization" in the scientific community (I am a PhD student). It may be called complexity.
Anyway, you're right. Humans probably cannot give rise to a new body plan without some macromutations (in development genes for instance), and viable macromutations never were revealed in the wild, AFAIK.
But maybe humans can evolve in something quite different in morphology and "ecology" even if the body plan remains the same, the same way some dinosaurs evolved into birds.

However, it is plausible that a sponge (as I said before) could evolve in something like a cnidarian, through mutation, drift and selection, IF its environment (including its competitors) allows this.

  
jeannot



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(Permalink) Posted: Jan. 29 2006,06:50   

Quote (Alan Fox @ Jan. 29 2006,10:16)
I'm sure that is the generally accepted view, Caledonian. Which is why JAD's assertion that evolution only takes a species to eventual extinction may have a ring of truth. Once a species has found its niche, rapid environmental change will leave it "high and dry" and less developed species can take over the territory.

"Is ecological specialization a dead-end ?"
"The jack-of-all-trades is master of none"
Theses two sentences have been the subject of manny debates in the scientific world. You can find hundreds (if not thousands) of papers on that topic. ;)

Edit: it is not scientifically correct to say that a species "finds its niche" since the concept of niche is defined by the species itself. A species always fits in its ecological niche.
You could say "a species becomes specialized" or "a species fits in its new environment" or "a species changes its habitat and resources"...

  
Caledonian



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(Permalink) Posted: Jan. 29 2006,06:57   

Thank you for the terminology correction.  It's been a long time since I studied biology, and quite frankly I've forgotten most of the technical terms.

My impression is that even sponges are far more complex than whatever ur-creatures gave rise to all of the strange body plans we see from the Cambrian.  I suspect that life may have lost the flexibility needed to produce complexity from scratch.

Would modern bacteria ever develop into multicellular organisms if all other forms of life were destroyed?  Algal mats might be able to start over... maybe.

  
jeannot



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(Permalink) Posted: Jan. 29 2006,07:12   

Quote (Caledonian @ Jan. 29 2006,12:57)
Thank you for the terminology correction.  It's been a long time since I studied biology, and quite frankly I've forgotten most of the technical terms.

My impression is that even sponges are far more complex than whatever ur-creatures gave rise to all of the strange body plans we see from the Cambrian.  I suspect that life may have lost the flexibility needed to produce complexity from scratch.

Would modern bacteria ever develop into multicellular organisms if all other forms of life were destroyed?  Algal mats might be able to start over... maybe.

Well, I don't think that modern sponges are so different from cambrian sponges, but I'm not a paleontologist.

Was the ancestor of all the animals something we would assign to the porifera phylum? Or something else much simpler? I think no one knows.
But remember, animals are just very tiny branch in the tree of life.

  
Russell



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(Permalink) Posted: Jan. 29 2006,07:20   

Quote
Would modern bacteria ever develop into multicellular organisms if all other forms of life were destroyed?
My guess is "yes", but maybe only after "de-differentiating" somewhat. Because "modern bacteria" are also somewhat (I want to say "specialized", but maybe I should say "compromised in pluripotentiality by their complexity".)

My guess is that the ur-eukaryote - our ancestor that resulted from the fusion of the nuclear and mitochondrial genomes - was originally an awkward creature, not likely to survive competition with modern life forms.

--------------
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jeannot



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(Permalink) Posted: Jan. 29 2006,07:30   

Quote (Russell @ Jan. 29 2006,13:20)
Quote
Would modern bacteria ever develop into multicellular organisms if all other forms of life were destroyed?
My guess is "yes", but maybe only after "de-differentiating" somewhat. Because "modern bacteria" are also somewhat (I want to say "specialized", but maybe I should say "compromised in pluripotentiality by their complexity".)

You may be right, but we don't know anything about this.

For example, the modern stromatolites don't look very different from precambrian fossiles.

  
Mr_Christopher



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(Permalink) Posted: Jan. 29 2006,17:26   

Quote (O. Johnson @ Jan. 29 2006,09:31)
Kirk to Enterprise.  

Beam me up, Scotty.  There's no intelligent life here.  

Kirk Out.

Dr Ottis, could we get your thoughts on the Dembski/Behe proposition that there exists a real possibility that the intelligent designer may in fact be a Klingon?  And your opinion on the testability of the Dembski/Behe inspired "Time Traveler" and "Space Aliens" theory of design.  

You'd be the best if you would shed some light on these theories advanced by two leading intelligent design theorists William Dembski and Michael Behe, especially if you could frame it in language that some of us average Joes will understand.  

Cheers and thanks in advance.

--------------
Uncommon Descent is a moral cesspool, a festering intellectual ghetto that intoxicates and degrades its inhabitants - Stephen Matheson

  
slpage



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(Permalink) Posted: Jan. 30 2006,09:11   

Quote (stevestory @ Jan. 28 2006,11:43)
Man, there are some idiots over there at Uncommon Pissant:

Quote
Not only is Dr. Davison an intellectual giant, he is also a giant of intellectual honesty. Truly a rare combination.

Comment by dougmoran — January 28, 2006 @ 10:46 am

A bit disturbing that someone would actually think that of Davison.

As an aside - Davison is not an emeritus prof at UVM.  He is just retired.

  
Alan Fox



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(Permalink) Posted: Jan. 30 2006,10:34   

Quote
As an aside - Davison is not an emeritus prof at UVM.  He is just retired.


I could try a bluff here and say "that's why I put 'Emertitus'." It was, however, just a typo. My bad, as you colonials put it. :)

  
Stephen Elliott



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(Permalink) Posted: Jan. 30 2006,23:54   

Has anybody read this from JAD?

http://www.uvm.edu/~jdavison/davison-manifesto.html

I have just printed it out and will read it later.
At first glance I reckon it will be too technical for me to properly understand.

  
Chris Hyland



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(Permalink) Posted: Jan. 31 2006,04:57   

Quote
I have just printed it out and will read it later


It’s an interesting read, although if you’re looking to try and refute it I wouldn’t bother. I asked him a series of questions on his post on UD, and just got this in reply:
Quote
I don’t know how many times I have to say this but chance never had anything to do with either evolution or development. Got that? Write that down.


The problem with any 'frontloading' hypothesis is that it requires complete predetermination of all environmental and random genetic changes. However since he has stated in other posts on UD that he believes this is the case, this gets around most criticisms of his theory.

  
Stephen Elliott



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(Permalink) Posted: Jan. 31 2006,05:44   

Quote (Chris Hyland @ Jan. 31 2006,10:57)
Quote
I have just printed it out and will read it later


It’s an interesting read, although if you’re looking to try and refute it I wouldn’t bother. I asked him a series of questions on his post on UD, and just got this in reply:
Quote
I don’t know how many times I have to say this but chance never had anything to do with either evolution or development. Got that? Write that down.

Oh, I wouldn't atempt to refute it. My knowledge of biology/evolution is not sufficient.

As for trying to argue with JAD, that is another waste of time. JAD tends to either ignore arguments or go on a rant. However, he does sometimes answer questions.

It's a shame really. JAD does have a lot of knowledge. It is a pity that he does not respond better to critical questioning.

  
Alan Fox



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(Permalink) Posted: Jan. 31 2006,06:49   

Stephen wrote

Quote
JAD does have a lot of knowledge.


I'm not so sure. he seems stuck in a time warp, and does not seem to have taken on board (in fact rather utterly rejected) any biological developments since the seventies. Look at the sources he constantly quotes; all dead and all but one or two retired before the genetic code had been elucidated.

  
Alan Fox



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(Permalink) Posted: Jan. 31 2006,07:00   

For example, do you think we can learn anything from this rant on UD?

  
Arden Chatfield



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(Permalink) Posted: Jan. 31 2006,07:10   

:00-->
Quote (Alan Fox @ Jan. 31 2006,13:00)
For example, do you think we can learn anything from this rant on UD?

Agreed. I think Davison's 'manifestos' are far more about him wrestling with his own cranky internal demons than about any kind of external reality that others can observe.

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"Rich is just mad because he thought all titties had fur on them until last week when a shorn transvestite ruined his childhood dreams by jumping out of a spider man cake and man boobing him in the face lips." - Erasmus

  
Stephen Elliott



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(Permalink) Posted: Jan. 31 2006,07:43   

Quote (Alan Fox @ Jan. 31 2006,13<!--emo&:0)
For example, do you think we can learn anything from this rant on UD?

LOL. Not at all.

JAD does have a good knowledge of biology though.

The reason I say this, I remember a while ago on PT. There was an article about dinosaur eggs. It asked a question. JAD gave an answer. It was imediately dissmised by the first few commenters (JAD is a crank after all). Turned out, JAD was right.

Don't forget JAD does have a PhD in biology. As cranky as he is, he does have some knowledge of the subject.

Don't missunderstand me. I am not saying JAD is always correct. Just saying that he is not an ignorant fool, no mater how hard he tries to give that impression.
:)

  
Caledonian



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(Permalink) Posted: Feb. 01 2006,03:28   

Oh, he's an ignorant fool - but with an extensive knowledge of biology.

  
Louis



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(Permalink) Posted: Feb. 01 2006,06:01   

People like JAD make me wonder about a few things. Look for example at Ghost of Paley. The guy is quite clearly intelligent and quite clearly unhinged. The other option of course is that he is a parody, deliberately designed to rile the scientists.

GOP is clearly someone who knows how to find the literature he wants (it appears he can't read it for comprehension however) on biological subjects. He appears to know enough general science to be able to quote at least vaguely relevant things (his predictions leave a lot to be desired by modern standards however).

Is GOP JAD or someone much like him?

--------------
Bye.

  
Stephen Elliott



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(Permalink) Posted: Feb. 01 2006,06:11   

I seriously doubt that GOP and JAD are the same person.

GOP answers too many questions without going into a rant.

JAD has more biology knowledge.

If it is the same person, he is a very good actor.

  
Lou FCD



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(Permalink) Posted: Dec. 20 2007,12:40   

There is a new thread for discussing our friendly neighborhood DAJ.

Topic Closed.

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