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  Topic: Prescribed Evo. Hypothesis Boosting, Cheerleading for PEH goes here.< Next Oldest | Next Newest >  
oldmanintheskydidntdoit



Posts: 4999
Joined: July 2006

(Permalink) Posted: Mar. 10 2010,04:00   

Quote (Patrickarbuthnot @ Mar. 10 2010,03:52)
Okay now I understand where your coming from.Thank you for explaining it. I will proceed to read her work then with precautions, thank you.

Once you've read it perhaps you could comment on how you feel UncommonDescent has represented her work?

As you linked to them as an alternative viewpoint on this issue I'd be interested to see if you go along with them after actually reading what they are writing about.

--------------
I also mentioned that He'd have to give me a thorough explanation as to *why* I must "eat human babies".
FTK

if there are even critical flaws in Gauger’s work, the evo mat narrative cannot stand
Gordon Mullings

  
Patrickarbuthnot



Posts: 21
Joined: Feb. 2010

(Permalink) Posted: Mar. 10 2010,05:12   

Quote (oldmanintheskydidntdoit @ Mar. 10 2010,04:00)
Quote (Patrickarbuthnot @ Mar. 10 2010,03:52)
Okay now I understand where your coming from.Thank you for explaining it. I will proceed to read her work then with precautions, thank you.

Once you've read it perhaps you could comment on how you feel UncommonDescent has represented her work?

As you linked to them as an alternative viewpoint on this issue I'd be interested to see if you go along with them after actually reading what they are writing about.

oldmanintheskydidntdoit  I will,  but just so you know I pulled their article up when I put her name in the search engine. I don't read their articles unless they are pulled up while  looking subjects up by Google. :)

--------------
Thomas Edison said: “The doctor of the future will give no medicine, but will interest her or his patients in the care of the human frame, in a proper diet, and in the cause and prevention of disease.”

  
Alan Fox



Posts: 1365
Joined: Aug. 2005

(Permalink) Posted: Mar. 10 2010,07:43   

Sorry I missed this thread (visiting sick mother with no internet connection!).

To those speculating on a JAD sock, John only managed to use a puppet a while ago (Dr Johnson, I think it was) because Dave Springer set it up for him and emailed him the login details. He just isn't that savvy!

@ Dublin Evans (if he hasn't flounced):

How does the PEH explain lockstep of organism to niche? I recall John Davison as fond of remarking " the environment had nothing to do with it".

ETA punctuation

  
Henry J



Posts: 4013
Joined: Mar. 2005

(Permalink) Posted: Mar. 10 2010,17:10   

Quote
she stated " Margulis strongly opposes the idea, widely held within the scientific community, that the driving force in evolution is competition, and thinks cooperative and symbiotic relationships are underemphasized by many evolutionary scientists.

That sounds to me more like a quibble over details than a disagreement with basics. After all, if behavior evolves to become more cooperative, it seems like it would be because populations in which members are more cooperative are on average more successful than populations in which the members weren't as cooperative. (A similar thought would apply to symbiotic relationships.)

Henry

  
Henry J



Posts: 4013
Joined: Mar. 2005

(Permalink) Posted: Mar. 10 2010,17:19   

(duplicate deleted)

  
Patrickarbuthnot



Posts: 21
Joined: Feb. 2010

(Permalink) Posted: Mar. 10 2010,23:24   

Quote (Alan Fox @ Mar. 10 2010,07:43)
Sorry I missed this thread (visiting sick mother with no internet connection!).

To those speculating on a JAD sock, John only managed to use a puppet a while ago (Dr Johnson, I think it was) because Dave Springer set it up for him and emailed him the login details. He just isn't that savvy!

@ Dublin Evans (if he hasn't flounced):

How does the PEH explain lockstep of organism to niche? I recall John Davison as fond of remarking " the environment had nothing to do with it".

ETA punctuation

Sorry,  I think I inadvertently started  a PEH/Symbiosis debate.



[Banned user text deleted - WRE]

Edited by Wesley R. Elsberry on Mar. 11 2010,06:36

--------------
Thomas Edison said: “The doctor of the future will give no medicine, but will interest her or his patients in the care of the human frame, in a proper diet, and in the cause and prevention of disease.”

  
Wesley R. Elsberry



Posts: 4465
Joined: May 2002

(Permalink) Posted: Mar. 11 2010,06:37   

John A. Davison was banned for cause. Posting by proxy is not an option.

If you have your own thoughts about PEH, those would be fine to post.

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

    
Patrickarbuthnot



Posts: 21
Joined: Feb. 2010

(Permalink) Posted: Mar. 11 2010,06:43   

Quote (Wesley R. Elsberry @ Mar. 11 2010,06:37)
John A. Davison was banned for cause. Posting by proxy is not an option.

If you have your own thoughts about PEH, those would be fine to post.

Thank You Dr. Elsberry I do have a lot of reading ahead of me. :)

--------------
Thomas Edison said: “The doctor of the future will give no medicine, but will interest her or his patients in the care of the human frame, in a proper diet, and in the cause and prevention of disease.”

  
Wesley R. Elsberry



Posts: 4465
Joined: May 2002

(Permalink) Posted: Mar. 11 2010,06:44   

"Patrickarbuthnot":

Quote

Sorry,  I think I inadvertently started  a PEH/Symbiosis debate.


You might occasionally check the thread title. It sometimes gives clues concerning what the thread topic is. This thread's title is "Prescribed Evo. Hypothesis Boosting", so one has an expectation that the comments entered within it have something to do with PEH. If you aren't meaning to comment on PEH, find a more appropriate thread for your comment. We only have a few thousand to choose from.

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

    
oldmanintheskydidntdoit



Posts: 4999
Joined: July 2006

(Permalink) Posted: Mar. 11 2010,07:17   

Quote (Patrickarbuthnot @ Mar. 10 2010,05:12)
Quote (oldmanintheskydidntdoit @ Mar. 10 2010,04:00)
Quote (Patrickarbuthnot @ Mar. 10 2010,03:52)
Okay now I understand where your coming from.Thank you for explaining it. I will proceed to read her work then with precautions, thank you.

Once you've read it perhaps you could comment on how you feel UncommonDescent has represented her work?

As you linked to them as an alternative viewpoint on this issue I'd be interested to see if you go along with them after actually reading what they are writing about.

oldmanintheskydidntdoit  I will,  but just so you know I pulled their article up when I put her name in the search engine. I don't read their articles unless they are pulled up while  looking subjects up by Google. :)

Fair enough.

--------------
I also mentioned that He'd have to give me a thorough explanation as to *why* I must "eat human babies".
FTK

if there are even critical flaws in Gauger’s work, the evo mat narrative cannot stand
Gordon Mullings

  
jeannot



Posts: 1200
Joined: Jan. 2006

(Permalink) Posted: Mar. 11 2010,08:08   

On Margulis: I have not read her book, but from reviews I can see here and there, I can only concur with her critics. Her view on speciation is not supported by studies on natural populations.

I may expand on this topic, which have been my area of research for the past 4 years. At best, it may inform our friend Patrickarbuthnot and clear some early misconceptions on speciation (for example, the view that speciation rarely involves natural selection).
Contrarily to Margulis' opinion, there is considerable evidence that speciation involves genetic changes (point mutations or other genomic rearrangements) and wherever these changes have been pinpointed, they appeared to have been subject to selection. In many cases divergent adaptation to distinct ecological niches has been shown to contribute to reproductive isolation. Geographical isolation will permit the fixation of these changes, though it is not an absolute requirement if divergent selection is strong.
On the other hand, there very little (or no) evidence that genetic drift and bottlenecks induce reproductive isolation (via the "genetic revolutions" proposed by Mayr, among other models). The various founder-effect speciation models have failed all laboratory tests. These were proposed to explain the frequent events of peripratric speciation (in founding populations), but in the end, it seems that natural selection in the new colonized habitat is the main driver of reproductive isolation (aided by geographical isolation).
Speciation by deleterious chromosomal rearrangements does not appear very common. The "stasipatric" model of speciation has recently been discredited in the biological model where it was first proposed (Australian grasshoppers or something). But chromosomal speciation requires more investigation. It could act in mammals, but the only studied case I know is the house mouse. There may be a couple of other candidate models though.
Speciation by polyploidization is frequent in plants (especially ferns), but less common than the classical model (selected genetic changes in isolated populations) and rare in animals.

Overall, it seems that Margulis gives too much importance to endosymbiosis. Although it certainly enabled the colonization of new niches (in insects in particular), thereby contributing to biodiversity, a direct link to speciation is not demonstrated.
It is sad that Margulis seems to embrace controversial hypotheses without looking carefully at the available data. I am not judging from her book (which I haven't read), but from the recent fiasco at PNAS, where she communicated this ridulous paper advocating the hypothesis that caterpillars came from velvet worms.  :(

  
Patrickarbuthnot



Posts: 21
Joined: Feb. 2010

(Permalink) Posted: Mar. 11 2010,23:08   

Quote (jeannot @ Mar. 11 2010,08:08)
On Margulis: I have not read her book, but from reviews I can see here and there, I can only concur with her critics. Her view on speciation is not supported by studies on natural populations.

I may expand on this topic, which have been my area of research for the past 4 years. At best, it may inform our friend Patrickarbuthnot and clear some early misconceptions on speciation (for example, the view that speciation rarely involves natural selection).
Contrarily to Margulis' opinion, there is considerable evidence that speciation involves genetic changes (point mutations or other genomic rearrangements) and wherever these changes have been pinpointed, they appeared to have been subject to selection. In many cases divergent adaptation to distinct ecological niches has been shown to contribute to reproductive isolation. Geographical isolation will permit the fixation of these changes, though it is not an absolute requirement if divergent selection is strong.
On the other hand, there very little (or no) evidence that genetic drift and bottlenecks induce reproductive isolation (via the "genetic revolutions" proposed by Mayr, among other models). The various founder-effect speciation models have failed all laboratory tests. These were proposed to explain the frequent events of peripratric speciation (in founding populations), but in the end, it seems that natural selection in the new colonized habitat is the main driver of reproductive isolation (aided by geographical isolation).
Speciation by deleterious chromosomal rearrangements does not appear very common. The "stasipatric" model of speciation has recently been discredited in the biological model where it was first proposed (Australian grasshoppers or something). But chromosomal speciation requires more investigation. It could act in mammals, but the only studied case I know is the house mouse. There may be a couple of other candidate models though.
Speciation by polyploidization is frequent in plants (especially ferns), but less common than the classical model (selected genetic changes in isolated populations) and rare in animals.

Overall, it seems that Margulis gives too much importance to endosymbiosis. Although it certainly enabled the colonization of new niches (in insects in particular), thereby contributing to biodiversity, a direct link to speciation is not demonstrated.
It is sad that Margulis seems to embrace controversial hypotheses without looking carefully at the available data. I am not judging from her book (which I haven't read), but from the recent fiasco at PNAS, where she communicated this ridulous paper advocating the hypothesis that caterpillars came from velvet worms.  :(

If you don't mind I will ask her that very thing in a e-mail and see what she says? I don't necessarily believe her hypothesis is correct I just am interested in her research.

--------------
Thomas Edison said: “The doctor of the future will give no medicine, but will interest her or his patients in the care of the human frame, in a proper diet, and in the cause and prevention of disease.”

  
jeannot



Posts: 1200
Joined: Jan. 2006

(Permalink) Posted: Mar. 12 2010,02:16   

Actually I am not that much interested in her view on speciation and I do not have much time to spend on this. Sorry.

EDIT: Sorry, I misread. I thought you were asking me to write her an email.

Well, do as you like.

  
Wesley R. Elsberry



Posts: 4465
Joined: May 2002

(Permalink) Posted: Mar. 12 2010,07:24   

"Patrickarbuthnot":

 
Quote

Sorry,  I think I inadvertently started  a PEH/Symbiosis debate.


Given that PEH is a frontloading conjecture and endosymbiosis is a hypothesis of contingent interaction, it ought to be a very short debate. I think I've pointed that out before.

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

    
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