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#1 mike the wiz

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Posted 11 July 2017 - 04:08 AM

 

 

As of October 2012, the NCSE list had 1229 names, compared with 840 on the Discovery Institute list. If we count only those persons on these two lists who had a Ph.D. degree and/or professional position in a core field closely related to evolution (Anatomy, Anthropology, Bacteriology, Biochemistry, Biology, Biophysics, Botany, Ecology, Entomology, Epidemiology, Genetics, Geology, Geophysics, Molecular Biology, Microbiology, Neurophysiology, Paleontology, Physiology, Taxonomy, Virology or Zoology), who thus are particularly well-qualified to make such a declaration, then 683 (55.6%) of the names on the NCSE list were so qualified, compared with only 236 (28.1%) of the Discovery Institute list, according to a detailed check performed by the present author. If we then further limit the Discovery Institute core field list to those persons named Steve or one of the variants above, so that the size of this list can be directly compared with the NCSE core field list, then only two signers remain (in general agreement with the fact that persons named Steve or one of the above variants constitute roughly 1% of the U.S. population)

 

From; http://www.scienceme...s-evolution.php

 

In this article they compared a list scientists signed, as doubting Darwinism, from the Discovery Insitute, to a list compiled for belief in evolution.

 

The evolutionist reponse was to create a "Steve" list in honour of Gould, to see how many Steves signed the affirmation that scientists believe evolution is a well supported fact, in so many words.

 

They then compared lists, and rejected many scientists on the discovery institute's list because those scientists weren't in a field that was part of evolution (non-overlapping magisteria one might say).

 

The objective was obviously to show that the "Steves" alone on the evo list would outnumber the Steves on the discovery list.

 

The conclusion was ultimately that a very, very tiny percentage of Steves doubt Darwinism. ("What If" it seems Ayala was very much in support of Darwinism from his quoted statement).

 

My analysis of this statistic, my critical analysis is that they did not seem to mention how many Steves did "NOT" sign the list. I would also say that it is a rhetorical device to limit the list to, "Steves" because of the possibility that there may simply by chance, be people without that name that doubt Darwinism, simply by happenstance. 

 

Conclusion; It seems reasonable to me to at least suppose there is some possibility that if there was a number of scientists that didn't sign the Steve list, that they are at least harbouring some doubts about Darwinism, possibly. ("some" Steves might have NOT signed either list)

 

Is it a fair comparison then? 

 

It seems to me there is a lot of room here for the possibility that people won't sign the Discovery Institute's list because of peer-pressure to conform to what science accepts, which is evolution, and it seems reasonable some Steves may not have signed the list. I would like to now how many Steves didn't sign the list.

 

Disclaimer; I think the article isn't without merit, in that it was clever to rule out those names that don't overlap with any area of evolutionary science.

 

Conclusion: I think the relevant figure is that 28% of scientists in the core fields of evolution doubt Darwinism. (my error, what can I say, I write fast but I also read fast.) :D

 

Disclaimer; I admit I haven't given great time to reading this article, as I thought that could be done more and discussed more during the topic, and I suspect there are people better qualified to understand the statistics than I.



#2 mike the wiz

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Posted 11 July 2017 - 04:19 AM

 

 

Link: In short, no matter how one objectively compares these lists, it is a fair conclusion that several hundred times as many well-qualified professional scientists accept the main precepts of evolution as dissent from them. And, given that the number of signers of the Discovery Institute list has hardly grown at all in the past two or three years, there is no indication that the number of dissenting scientists is sharply growing relative to those who have declared their support of evolution.

 

The blue part seems like a non-sequitur, if people are under peer-pressure to not sign.


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#3 mike the wiz

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Posted 11 July 2017 - 04:28 AM

Of course this topic hasn't yet discussed WHY these majority of science people accept evolution. It seems to me, tautologous, that people educated in areas that cover evolution, will accept evolution.

 

A bit like saying, "how many golfers would sign a list agreeing that golf is the best sport on the planet?"

 

Is it their areas of study convincing them. Or, were they convinced and passionate about those areas of study, passionately believing them, BEFORE they studied those fields, which is why they really studied those fields?

 

It seems to me to be pretty unlikely a person wanting to become an evolutionary biologist for example, would not already be passionate about the evolution theory, and therefore the chances of them ever rejecting it, after that belief is compounded by their studies, seems incredibly remote.

 

:acigar:



#4 what if

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Posted 11 July 2017 - 10:09 AM

("What If" it seems Ayala was very much in support of Darwinism from his quoted statement).

he apparently was until that chicago conference on macro evolution.
just like he (ayala) said ( and it supports melonis contention about the value of population genetics) he did not believe stasis in the record but he was then convinced that small changes do not accumulate.
in effect he (ayala) was basing his previous "beliefs" on a meaningless method (population genetics).

#5 what if

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Posted 11 July 2017 - 10:19 AM

[font=verdana, geneva, sans-serif]Of course this topic hasn't yet discussed WHY these majority of science people accept evolution.

the answer is simple, it's the only real rational option.
i must immediately qualify that though.
science simply doesn't know how life got here, it is simply clueless as to how it came about.
the same can be said of animal phyla.
the really curious thing is, these are the exact areas that god claims is his doing.
can anyone really ascribe that to coincidence?
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#6 mike the wiz

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Posted 11 July 2017 - 10:35 AM

Yes it seems with population genetics, as with everything else, "evolution", those changes can occur without macro having any relevance. 



#7 what if

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Posted 11 July 2017 - 11:30 AM

Yes it seems with population genetics, as with everything else, "evolution", those changes can occur without macro having any relevance. 

according to koonin, macroevolution (the crossing of animal phyla) isn't observed in the fossil record.
be advised that the reviewers of his paper had no comment on the above.
they did however call him on his "ready made" comment in regards to the appearance of animal phyla.

BTW, i no longer believe anything the modern synthesis says. none of it.

i just hope that scientists such as koonin, meloni, lynch, noble, oakley, and others can keep their voices heard.

be advised that the above scientists do not reject evolution, but they DO say the modern synthesis is dead.

i'm really curious about a comment made by meloni in regards to genes and the environment.
apparently this isn't a one way street where genes are affected by the environment, but they affect each other.

#8 mike the wiz

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Posted 11 July 2017 - 12:21 PM

"What if", But just playing the advocate for a moment and speaking as perhaps Goku and Piasan would, aren't these just a handful of scientists compared to the whole?

 

Really as a creationist I am obviously considered much closer to a flat earther by evolutionists, than you would be. But please note one thing - did you notice this article with the statistics basically gave a comment that there was no hope for YEC?

 

Doesn't that strike you as rather interesting that they would feel the need to say that?

 

Like me, does that strike you almost as an irrelevantly insecure comment? Why even mention YEC if the issue was all to do with Discovery Institute's attempt to ascertain doubt in Darwinism?

 

To me that strikes me as someone revealing their true motives - what this is really all about is their fear that people will believe in God as the Creator rather than evolution. They feel the need to mention YEC. For me that was a moment where I thought; "wow - you're so insecure about YEC".


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#9 wibble

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Posted 11 July 2017 - 02:07 PM

according to koonin, macroevolution (the crossing of animal phyla) isn't observed in the fossil record.
be advised that the reviewers of his paper had no comment on the above.


Do you consider that there is evidence of macroevolution in the fossil record after the first appearance of animal phyla ?



#10 what if

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Posted 11 July 2017 - 05:00 PM

"What if", But just playing the advocate for a moment and speaking as perhaps Goku and Piasan would, aren't these just a handful of scientists compared to the whole?

there are others, a large group of them.
also be aware that the scientific establisnment itself WILL ignore valid evidence in favor of a theory.
furthermore, the authors of these types of papers will be ridiculed.
even today, you will see evolutionists pushing the modern synthesis when in fact it's wrong.
genomes show little, if any, signs of optimum design.
some will have you believe that the changes aren't that different, but they are.
every single tenet of the modern synthesis has either been overturned or rewritten.
what does this tell you mike?
that all is well with the modern synthesis?

Really as a creationist I am obviously considered much closer to a flat earther by evolutionists, than you would be. But please note one thing - did you notice this article with the statistics basically gave a comment that there was no hope for YEC?
 
Doesn't that strike you as rather interesting that they would feel the need to say that?

as soon as you mention statistics, i reach for my gun.
i believe statistically you can prove ice boils water.
yes, statistics is a valuable tool, but unless you know all the variables you can be easily misled.
false correlations are far too easy with statistics.

Like me, does that strike you almost as an irrelevantly insecure comment? Why even mention YEC if the issue was all to do with Discovery Institute's attempt to ascertain doubt in Darwinism?

because there is basically 2 sides.
both are trying to prove their point.
one way of doing that is by implying the other side is weaker or has fewer adherents.

To me that strikes me as someone revealing their true motives - what this is really all about is their fear that people will believe in God as the Creator rather than evolution. They feel the need to mention YEC. For me that was a moment where I thought; "wow - you're so insecure about YEC".

could be.
most will blame this on atheists, but a very large part is directed against christianity.
why christianity?
is this being sourced from islam, or is it because christianity is indeed the true religion?
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#11 what if

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Posted 11 July 2017 - 06:21 PM

according to koonin, macroevolution (the crossing of animal phyla) isn't observed in the fossil record.
be advised that the reviewers of his paper had no comment on the above.


Do you consider that there is evidence of macroevolution in the fossil record after the first appearance of animal phyla ?

i would have swore i answered this post.
maybe i did but didn't submit it for some reason.

no, there isn't any evidence of phyla being crossed.
there is no evidence of phyla descending from each other either.

the catchword here is macroevolution and what it means.
the crossing of the phyla boundary would be macroevolution in my opinion.
there is no fossil evidence that supports it either.
due to epigenetics and transposons, we can have a great variety of organisms with the same basic phylletic structure.
and none of it would require a "gradual accumulation".
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#12 Blitzking

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Posted 11 July 2017 - 11:17 PM

Of course this topic hasn't yet discussed WHY these majority of science people accept evolution. It seems to me, tautologous, that people educated in areas that cover evolution, will accept evolution.
 
A bit like saying, "how many golfers would sign a list agreeing that golf is the best sport on the planet?"
 
Is it their areas of study convincing them. Or, were they convinced and passionate about those areas of study, passionately believing them, BEFORE they studied those fields, which is why they really studied those fields?
 
It seems to me to be pretty unlikely a person wanting to become an evolutionary biologist for example, would not already be passionate about the evolution theory, and therefore the chances of them ever rejecting it, after that belief is compounded by their studies, seems incredibly remote.
 
:acigar:



I put ZERO credibility in these so called "polls" I would put more confidence in a REAL enquiry that would have to be done HONESTLY..

And would go like this.....(We COULD do this if we WANTED to BTW..)

All of the "qualified" scientists would be hooked up to a polygraph machine and given this question ANONYMOUSLY so NO ONE would know the answers given by each party and ONLY the overall Answers would be given but NOT how anyone personally answered..

And the question would be the following..

Do you believe that Abiogenesis, followed by UCA for all flora and fauna is the mechanism for our existence here on planet Earth? TRUE or FALSE..

I would love to wager that we would get over 90% who said FALSE....

But this will never happen as Evolutionists dont WANT to know the REAL truth about much of ANYTHING related to this topic...

They prefer to stick with duplicitous marketing ploys like "Micro Evolution" and "Change over time"....


"There are gaps in the fossil graveyard, places where there should be intermediate forms, but where there is nothing whatsoever instead. No paleontologist..denies that this is so. It is simply a fact, Darwin's theory and the fossil record are in conflict."

(Dr. David Berlinsky)
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#13 mike the wiz

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Posted 12 July 2017 - 01:49 AM

That's a clever idea BK, would be better than this Steve test.

 

Is there also a difference between only collecting Steve's for evolution by saying, "Steves please, we're recruiting Steves", but with Discovery Institute's test they did't request Steves, they just compared the final amount of Steves.

 

It seems to me if you specifically say, "I need Steves" the chances are more Steves will come and sign than if you just say, "any scientists please sign."

 

It seems a fair test would be to request Steves for both groups. I may be wrong of course.



#14 Schera Do

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Posted 12 July 2017 - 03:39 AM

That's a clever idea BK, would be better than this Steve test.
 
Is there also a difference between only collecting Steve's for evolution by saying, "Steves please, we're recruiting Steves", but with Discovery Institute's test they did't request Steves, they just compared the final amount of Steves.
 
It seems to me if you specifically say, "I need Steves" the chances are more Steves will come and sign than if you just say, "any scientists please sign."
 
It seems a fair test would be to request Steves for both groups. I may be wrong of course.

.
I think it is a bad idea to restrict respondents to those with a variation of that name. It's asking for trouble. The assumption is that the Steve's represent the population (the sample).

#15 wibble

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Posted 12 July 2017 - 02:22 PM

 

Do you consider that there is evidence of macroevolution in the fossil record after the first appearance of animal phyla ?


no, there isn't any evidence of phyla being crossed.
there is no evidence of phyla descending from each other either.

 

That's not what I asked
 

the catchword here is macroevolution and what it means.
the crossing of the phyla boundary would be macroevolution in my opinion.
there is no fossil evidence that supports it either.


You're not very good at giving straight answers are you. I asked whether you consider there is evidence in the fossil record of macroevolution after the first phyla appeared, not before.



#16 what if

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Posted 12 July 2017 - 03:20 PM

You're not very good at giving straight answers are you.

sometimes not, i tend to get confused at times.

I asked whether you consider there is evidence in the fossil record of macroevolution after the first phyla appeared, not before.

koonin says phyla arrived here ready made. (later changed to abruptly because a reviewer got excited over the term ready made).
koonin doesn't mention any specific phyla or a group of phyla.
as a matter of fact he specifically says:
The Cambrian explosion in animal evolution during which all the diverse body plans appear to have emerged almost in a geological instant is a highly publicized enigma.
- The Biological Big Bang model for the major transitions in evolution.htm

the above paper was published 2007

so, as of 2007 there are no transitionals between animal phyla.

furthermore, koonin rejects the mainstream explanation thusly:
Although molecular clock analysis has been invoked to propose that the Cambrian explosion is an artifact of the fossil record whereas the actual divergence occurred much earlier [36,37], the reliability of these estimates appears to be questionable [38]. In an already familiar pattern, the relationship between the animal phyla remains controversial and elusive.
- ibid.

#17 wibble

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Posted 12 July 2017 - 03:38 PM

 

You're not very good at giving straight answers are you.

sometimes not, i tend to get confused at times.

I asked whether you consider there is evidence in the fossil record of macroevolution after the first phyla appeared, not before.

koonin says phyla arrived here ready made. (later changed to abruptly because a reviewer got excited over the term ready made).
koonin doesn't mention any specific phyla or a group of phyla.
as a matter of fact he specifically says:
The Cambrian explosion in animal evolution during which all the diverse body plans appear to have emerged almost in a geological instant is a highly publicized enigma.
- The Biological Big Bang model for the major transitions in evolution.htm

the above paper was published 2007

so, as of 2007 there are no transitionals between animal phyla.

furthermore, koonin rejects the mainstream explanation thusly:
Although molecular clock analysis has been invoked to propose that the Cambrian explosion is an artifact of the fossil record whereas the actual divergence occurred much earlier [36,37], the reliability of these estimates appears to be questionable [38]. In an already familiar pattern, the relationship between the animal phyla remains controversial and elusive.
- ibid.

 

 

I agree, you do seem very confused. Why do you keep going on about the appearance of phyla in the Cambrian when I'm asking about evolution since ? You do realise that all the animals that ever existed in each phyla did not all appear in the Cambrian yeah ? How many Cambrian examples of Chordata can you give me ?



#18 what if

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Posted 12 July 2017 - 03:48 PM

You're not very good at giving straight answers are you.

sometimes not, i tend to get confused at times.

I asked whether you consider there is evidence in the fossil record of macroevolution after the first phyla appeared, not before.

koonin says phyla arrived here ready made. (later changed to abruptly because a reviewer got excited over the term ready made).
koonin doesn't mention any specific phyla or a group of phyla.
as a matter of fact he specifically says:
The Cambrian explosion in animal evolution during which all the diverse body plans appear to have emerged almost in a geological instant is a highly publicized enigma.
- The Biological Big Bang model for the major transitions in evolution.htm

the above paper was published 2007

so, as of 2007 there are no transitionals between animal phyla.

furthermore, koonin rejects the mainstream explanation thusly:
Although molecular clock analysis has been invoked to propose that the Cambrian explosion is an artifact of the fossil record whereas the actual divergence occurred much earlier [36,37], the reliability of these estimates appears to be questionable [38]. In an already familiar pattern, the relationship between the animal phyla remains controversial and elusive.
- ibid.

 
I agree, you do seem very confused. Why do you keep going on about the appearance of phyla in the Cambrian when I'm asking about evolution since ? You do realise that all the animals that ever existed in each phyla did not all appear in the Cambrian yeah ? How many Cambrian examples of Chordata can you give me ?

there is no evidence that the "body plan" boundary has been crossed
all evolution is within a specific body plan.
in effect there is no macroevolution.
species aren't the durable units of evolution, body plans are.

this is almost certain proof that epigenetics, transposons, and regulatory networks were operational at the time of eukaryote super groups.

also keep in mind that koonin does not doubt evolution.
(disclaimer because of the thread title.)

#19 Fjuri

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Posted 13 July 2017 - 12:06 AM

 

 

 

You're not very good at giving straight answers are you.

sometimes not, i tend to get confused at times.

I asked whether you consider there is evidence in the fossil record of macroevolution after the first phyla appeared, not before.

koonin says phyla arrived here ready made. (later changed to abruptly because a reviewer got excited over the term ready made).
koonin doesn't mention any specific phyla or a group of phyla.
as a matter of fact he specifically says:
The Cambrian explosion in animal evolution during which all the diverse body plans appear to have emerged almost in a geological instant is a highly publicized enigma.
- The Biological Big Bang model for the major transitions in evolution.htm

the above paper was published 2007

so, as of 2007 there are no transitionals between animal phyla.

furthermore, koonin rejects the mainstream explanation thusly:
Although molecular clock analysis has been invoked to propose that the Cambrian explosion is an artifact of the fossil record whereas the actual divergence occurred much earlier [36,37], the reliability of these estimates appears to be questionable [38]. In an already familiar pattern, the relationship between the animal phyla remains controversial and elusive.
- ibid.

 

 
I agree, you do seem very confused. Why do you keep going on about the appearance of phyla in the Cambrian when I'm asking about evolution since ? You do realise that all the animals that ever existed in each phyla did not all appear in the Cambrian yeah ? How many Cambrian examples of Chordata can you give me ?

 

there is no evidence that the "body plan" boundary has been crossed
all evolution is within a specific body plan.
in effect there is no macroevolution.
species aren't the durable units of evolution, body plans are.

this is almost certain proof that epigenetics, transposons, and regulatory networks were operational at the time of eukaryote super groups.

also keep in mind that koonin does not doubt evolution.
(disclaimer because of the thread title.)

 

I'm curious, since I'm unfamiliar with the term body plan:

Do a kolibri and a blue whale have the same body plan?



#20 Blitzking

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Posted 13 July 2017 - 12:53 AM

 

 

 

 

You're not very good at giving straight answers are you.

sometimes not, i tend to get confused at times.

I asked whether you consider there is evidence in the fossil record of macroevolution after the first phyla appeared, not before.

koonin says phyla arrived here ready made. (later changed to abruptly because a reviewer got excited over the term ready made).
koonin doesn't mention any specific phyla or a group of phyla.
as a matter of fact he specifically says:
The Cambrian explosion in animal evolution during which all the diverse body plans appear to have emerged almost in a geological instant is a highly publicized enigma.
- The Biological Big Bang model for the major transitions in evolution.htm

the above paper was published 2007

so, as of 2007 there are no transitionals between animal phyla.

furthermore, koonin rejects the mainstream explanation thusly:
Although molecular clock analysis has been invoked to propose that the Cambrian explosion is an artifact of the fossil record whereas the actual divergence occurred much earlier [36,37], the reliability of these estimates appears to be questionable [38]. In an already familiar pattern, the relationship between the animal phyla remains controversial and elusive.
- ibid.

 

 
I agree, you do seem very confused. Why do you keep going on about the appearance of phyla in the Cambrian when I'm asking about evolution since ? You do realise that all the animals that ever existed in each phyla did not all appear in the Cambrian yeah ? How many Cambrian examples of Chordata can you give me ?

 

there is no evidence that the "body plan" boundary has been crossed
all evolution is within a specific body plan.
in effect there is no macroevolution.
species aren't the durable units of evolution, body plans are.

this is almost certain proof that epigenetics, transposons, and regulatory networks were operational at the time of eukaryote super groups.

also keep in mind that koonin does not doubt evolution.
(disclaimer because of the thread title.)

 

I'm curious, since I'm unfamiliar with the term body plan:

Do a kolibri and a blue whale have the same body plan?

 

 

DON"T YOU HAVE ACCESS TO WICKED PEDIA FILES ?

 

 

Body plan
From Wikipedia, the free encyclopedia
 
Jump to: navigation, search
Animal_diversity.png
Modern groups of animals can be grouped by the arrangement of their body structures, so are said to possess different "body plans".

A body plan (also written bodyplan), Bauplan (German plural Baupläne), or ground plan is "an assemblage of morphological features shared among many members of a phylum-level group".[1]:33 The vertebrate body plan is one of many: invertebrates consist of many phyla.

This term, usually applied to animals, envisages a "blueprint" encompassing aspects such as symmetry, segmentation and limb disposition. Evolutionary developmental biology seeks to explain the origins of diverse body plans.

Body plans have historically been considered to have evolved in a flash in the Cambrian explosion, but a more nuanced understanding of animal evolution suggests gradual development of body plans throughout the early Palaeozoic.

 

 

History[edit]

The history of the discovery of body plans can be seen as a movement from a worldview centred on the vertebrates, to seeing the vertebrates as one body plan among many. Among the pioneering zoologists, Linnaeus identified two body plans outside the vertebrates; Cuvier identified three; and Haeckel had four, as well as the Protista with eight more, for a total of twelve. For comparison, the number of phyla recognised by modern zoologists has risen to 35.[1]

Linnaeus, 1735[edit]

In his 1735 book, Systema Naturæ, the Swedish botanist Linnaeus grouped the animals into quadrupeds, birds, "amphibians" (including tortoises, lizards and snakes), fish, "insects" (Insecta, in which he included arachnids, crustaceans and centipedes) and "worms" (Vermes). Linnaeus's Vermes included effectively all other groups of animals, not only tapeworms, earthworms and leeches but molluscs, sea urchins and starfish, jellyfish, squid and cuttlefish.[2]

Cuvier, 1817[edit]
200px-Haeckel_arbol_bn.png
 
Haeckel's 'Monophyletischer Stambaum der Organismen' from Generelle Morphologie der Organismen (1866) with the three branches Plantae, Protista, Animalia

In his 1817 work, Le Règne Animal, the French zoologist Georges Cuvier combined evidence from comparative anatomy and palaeontology[3] to divide the animal kingdom into four body plans. Taking the central nervous system as the main organ system which controlled all the others, such as the circulatory and digestive systems, Cuvier distinguished four body plans:[4]

  • I. with a brain and a spinal cord (surrounded by skeletal elements)[4]
  • II. with organs linked by nerve fibres[4]
  • III. with two longitudinal, ventral nerve cords linked by a band with two ganglia below the oesophagus[4]
  • IV. with a diffuse nervous system, not clearly discernible[4]

Grouping animals with these body plans resulted in four branches: vertebrates, molluscs, articulata (including insects and annelids) and zoophytes or radiata.

Haeckel, 1866[edit]

Ernst Haeckel, in his 1866 Generelle Morphologie der Organismen, asserted that all living things were monophyletic (had a single evolutionary origin), being divided into plants, protista, and animals. His protista were divided into moneres, protoplasts, flagellates, diatoms, myxomycetes, myxocystodes, rhizopods, and sponges. His animals were divided into groups with distinct body plans: he named these phyla. Haeckel's animal phyla were coelenterates, echinoderms, and (following Cuvier) articulates, molluscs, and vertebrates.[5]

Gould, 1979[edit]

Stephen J. Gould explored the idea that the different phyla could be perceived in terms of a Bauplan, illustrating their fixity. However, he later abandoned this idea in favor of punctuated equilibrium.[6]

Origin[edit]

20 out of the 36 body plans originated in the Cambrian period,[7] in the "Cambrian explosion",[8] However, complete body plans of many phyla emerged much later, in the Palaeozoic or beyond.[9]

The current range of body plans is far from exhaustive of the possible patterns for life: the Precambrian Ediacaran biota includes body plans that differ from any found in currently living organisms, even though the overall arrangement of unrelated modern taxa is quite similar.[10] Thus the Cambrian explosion appears to have more or less completely replaced the earlier range of body plans.[7]

Genetic basis[edit]

Genes, embryos and development together determine the form of an adult organism's body, through the complex switching processes involved in morphogenesis.

Developmental biologists seek to understand how genes control the development of structural features through a cascade of processes in which key genes produce morphogens, chemicals that diffuse through the body to produce a gradient that acts as a position indicator for cells, turning on other genes, some of which in turn produce other morphogens. A key discovery was the existence of groups of homeobox genes, which function as switches responsible for laying down the basic body plan in animals. The homeobox genes are remarkably conserved between species as diverse as the fruit fly and man, the basic segmented pattern of the worm or fruit fly being the origin of the segmented spine in man. The field of animal evolutionary developmental biology ('Evo Devo'), which studies the genetics of morphology in detail, is rapidly expanding[11] with many of the developmental genetic cascades, particularly in the fruit fly Drosophila, catalogued in considerable detail.[12]


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