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Author Topic:   Evolution and Increased Diversity
Brad McFall
Member (Idle past 5032 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 6 of 140 (423101)
09-19-2007 6:27 PM
Reply to: Message 1 by RAZD
09-19-2007 4:38 PM


Darwin's increase in diversity etc.
Someone reading Darwin's "Origin" one can encompass his notion of diversity via the angles here (only diagram in the book):

The line at the top is suppposed by Darwin to transform, back, into the boundaries of any given country, and generations later, there are six places variation supposedly wrought. Darwin's notion of diversification in form-making is tied to diversity triangulatable in space. It did not seem to me to be any old kind of novelty creation.
If a creationist wishes to argue not against Darwin's view but rather something created 100yrs or so later, they could simply point out the no one has followed up on Wright's notion of a gamodeme strictly. People are arguing whether or not Wright's complex process exists in nature but the question could be could man create isolatable breeding communties able to outevolve (into currently unoccupied regions of niche space) currently endemic genetic variations in nature, given nature.
I suspect however that a creationist position against macroevolution would looke pricipally to showing that Darwin's spatial restriction of diverification can not exist on our actual Earth and thus his process for giving rise to 5 lineages from two within a country necessarily collide. I have not made this determination. It might be possible however. Gould however takes the position that Darwin failed miserably to explain diversity hitching his bit to levels of selection rather than levels of organization.
I think Panbiogeographic statements can be read in part to provide the spatiality that is not simply a mirror image (among E, F G) as Darwin seems to have figured it. Temporally it matters how much time is supposed to be represented from the top to the bottom. The Earth is near spherical after all.

This message is a reply to:
 Message 1 by RAZD, posted 09-19-2007 4:38 PM RAZD has replied

Replies to this message:
 Message 7 by RAZD, posted 09-19-2007 6:56 PM Brad McFall has replied

  
Brad McFall
Member (Idle past 5032 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 8 of 140 (423133)
09-19-2007 9:24 PM
Reply to: Message 7 by RAZD
09-19-2007 6:56 PM


Re: Darwin's increase in diversity compared to Wright's
Yes Darwin did not make it clear how many generations are represented with each line.
He was however trying to apply Malthus and to do so requires some macrospatial boundary IN which to compare the geometric growth of reproductions to the arithemetic increase of the food. To be willing to reduce the places in an actual geography on Earth envisaged with this math to the petri dish while logically scaling ok, I find leads to suspcious use of the notion of "metric".
The diversity where, despite some extinction, becomes represented on both halves of the figure is to present how there need be NO LAW to the extinction of forms.There has to be an origin to the "species" with it. To say that the Mendel binomial not available to Darwin expunges his planar accompaniment to the words in the text seems like a cop out to me. It seems to me that by restricting one to a sphere rather than an infinite plane Darwin's diversification DOES become constrained in some visiable way. I would love to have some other way, other than words, to express this.
Now if one of course does reduce the scale, without any intention of disrupting the topology (definition of 'neighborhood')implicit AND one assumes that it may not be on the Earth that a "country" is supposed to present linearly as per the diagram, then in bringing it back to macro size after the process has commenced, one is not subject to my restrictive configuing because one has the Universe as the outside bound of any niche rather than the rotating and revolving place we can in our best of moods can still be phoned home.
If I reject Malthus, it is a piece of cake, to keep with your obervation, but it was in relying on that, that I think Darwin failed, not as Gould supposes, of failing to start with species selection but failing to realize that a number of things to be selected is not so easy to even describe let alone cut out of nature for human comprehension.
Correct me if I am wrong, but it seems to me that Wright's isolation by distance is simply the ability to genetically support any given branch"" of Darwins' whether extinct or extant in the picture.
Wright still maintained that some immigration from the population (as a whole) could still enter a given braching (Darwin compass of a country) This is why Wright spoke of that, THEN the stepping stone model (some where in between the middle of the diagram) then density dependence and now that then, a continuum(see quote below). If one is not a reductionist it is hard to simply accept the scaling operation creates not but a torque force of minsucle magnitude.
This continuum must be one to one and onto Darwin's linearity it seems to me. I have not tried it but it seems to me that the purely arithemetic and geometric properties of transfinite numbers may supply a different drawing board from which to circumspectly represent Darwin's reasoning but with a different, not restricted to the plane, resultant depiction. But then what a "number" means biologically would be composite of genotype and phenotype, and that being hard for one without the intuition to so proceed, is unlikely to motivate in readers. So it would be easier for me to stick to tyring to interpret the already suggested evolutionary ideas.
quote:
The simplest pattern of subdivision to deal with mathematically is the "island model." In this, in pure form, the population is divided into groups that are panmictic within themselves, except for reception of smal proportions of immigrants, representative of the population as a whole.
In most actual cases, immigrants come largely from beighboring groups and there is more or less "isolation by distance." Such patterns may be calssified by the degree of continuity of the population. The island model pases into the "stepping stone" model, this into the model of a continuum whith scattered clusters of high density, and this into the model of a uniform continuum.
page 290 in The Theory of Gene Frequencies by S Wright


This message is a reply to:
 Message 7 by RAZD, posted 09-19-2007 6:56 PM RAZD has seen this message but not replied

  
Brad McFall
Member (Idle past 5032 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 9 of 140 (423263)
09-20-2007 6:48 PM
Reply to: Message 2 by AdminQuetzal
09-19-2007 5:00 PM


revision of Darwin's increase in diversity
quote:
you want to debate. Is there a question in there somewhere?
RAZD came out after I posted with,
quote:
in that diagram you can see that diversity can increase but that it doesn't have to: there are several extinctions shown and places where a horizontal line would have more species than at the end.
I am suggesting that maybe IT DOES have to according to Darwin, but not necessarily by post neo-Darwinian assertions.
Look:
The question as RAZD has it put, is-is, are a-z "at the end" necessarily containin more species than on Darwin's A..L line of beginner's luck. In between I have labeled two lines "greater number" and "lesser number" to accord with Darwin's use of the word "number". The question is, are there actual places where a lineage would have more species than at the end. Where is the end?
This would depend on where Darwin's Fline necessarily is represented in my figure. This I have not determined.
It may be that a measure of adaptedness is needed as Dobshansky wrote in the 60s (quote available). Regardless GS Carter in 1957 wrote
quote:
In all these ways Darwin's theories semed to strike at the foundations of religion and metaphysics. Much of the conflict was inherent in the intellectual position of the nineteenth century. Sooner or later fundamentalist views were bound to come into conflict with the results of science, and the materialism of the scientists was already disputed but the metaphysicians. Darwin's book gave the shock that brought the conflict to the surface, but, i that shock had not been given, the causes of the conflict would still have been there and dispute would have taken place at some other time
a hundred years of evolution page 67

I feel that this outline of Darwin's depiction drawn via light cones in quaternionic space supplies the very "surface" mentioned by Carter.
Dobshansy subsequently wrote,
quote:
Adaptedness is in principle, measureable; in practice, the measurement is extremely difficult. Satisfactory methods of measuring the adaptedness especially in the adaptedness of populations, are yet to be devised. Awkward questions are sometimes asked, even by some biologists: In what sense can mankind be said to be better adapted than a fly or an alga or a bacterium? Are the so-called higher organisms in general any better adapted than the lower ones? If not, then was not the whole biological evolution a wasted effort? These questions are not easily answered in precise terms, and our inability to give such answers attests tothe unsatisfactory state of our understanding of the phenomena of adaptedness and of their roles in evolution.
Adaptedness and Fitness in Population Biology and Evolution 1967 p113

Gould has decided that the position on adaptations had hardened in this time frame. Instead of finding this surface I revised, he expects us to wear the cap of his team that finds instead the arguments within evolutionary discussions ARE those of Paley-Agassiz 'transmorgified' (read Darwin and Darwin's "god" here). If the surface I am presenting is a better rendition than Goulds' then perhaps there was NO hardening but rather a softening up and faliure to pursue questions to an end.
It seems to me that Stanley in the 70s who has said (quote in Lloyd's book) that "species selection" was never about general adaptedness may be correct historically but wrong rationally. It might be instead that the "hardening" was a failure to develop the methods called for by Dobshansky. Could it not be that the Gladyshev law contains such a law for the extinction of forms?
Now if your question turned into mine is not comphrended, all I can do is rephrase it. The culprit is probaby what the word population means and what a "check" is on one. That seems to underlie Hoot persistant use of sexual selection but that is not my conversation...
The places in dispute or under possible extinction directions seem to have been denoted by Carter with ,
quote:
These local populations of a species vary enormously in size, from the small number of individuals that may inhabit a pool of water to the many millions of a shoal of herring in the sea or of a planktonic species in a lake. All intermediates between these extremes of size occur, Further, this type of distribution is as general in the common species as in the rarer; the common species is distinguished rather by the shorter distances that separate its local populations than by any lack of distinctness between the populations .
The local populations of a species are isolated from each other more or less completely by the unsuitable environments that separate their localites. Here again there is very great variability. The isolation is probably almost complete between populations on islands separated by considerable streches of water, or in isolated bodies of water on land. In many other cases it may be much less complete, but recent study of ecology has shown that the movements of many animals are much less than might be expected, Populations of field mice separated by a few hundred yards have been found not to mix; snails do not travel more than a few yards in a year; and even the birds of a wood have been found not to mix with those of another wood a mile or so away. In all these cases there is a very definite isolation between populations which are by no means distant from each other.
These local and at least partially isolated populations may be called demes.
It is in these demes that micro-evolution goes on. As soon as two populations are isolated, they will begin to diverge, either in adaptation to small differences in their environments, or because mutations that occur in one do not occur in the other.
Carter op.cit page 149

For physicist's (using time as the scalar component (biology may? not use this))use of light cone representations with quaternions see
doing physics with quaternions

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 Message 2 by AdminQuetzal, posted 09-19-2007 5:00 PM AdminQuetzal has not replied

  
Brad McFall
Member (Idle past 5032 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 116 of 140 (440196)
12-11-2007 8:01 PM
Reply to: Message 113 by Elmer
12-11-2007 12:08 PM


question
quote:
IOW, your 'natural selection' can reduce a given amount of biosiversity all the way to zero, but it can never increase it by so much as a fraction. It was this flaw that, when pointed out to Darwin, sent him back to Lamarck [unacknowledged] for his 'pangenesis' explanation for increased variation and added complexity, i.e., increased biodiversity, among bioforms. And it is what prompted Fisher, Haldane, and Wright to postulate 'random genetic mutation' as the source of _increased_ biodiversity, simply because 'natural selection' could not and did not account for it.
How is one to take this paragraph? Can you tell me where in the literature ( somewhere on the topic of pangenesis ?) is there discussion of this “flaw” and if it really ”sent’ him back to Lamarck.
Richard Lewontin insists (I will happlily provide content to this effect if requested) that evolution today is one of a differential relation between organisms and environments so if Darwin in historical time went back to Lamarck then by today’s evo standard he, Darwin was flawed to do so because there is no actual environment in which this happened.
Now if one wishes to test or question what is the full differential implied by Lewontin and insist on some monophyly out of the pleunum of biological change then one might find that there was an equilibrium here or there, whatever the supposed litertature you connote denotes. So please it would help if I had some better idea of what you mean here. Is it just generally or is it to mean something like Darwin’s “laws of growth”.
As to what prompted FHW to postulate . well I think this thinking was more general - to the difference of Lysenko and Morgan for instance. Indeed my grandfather, a teacher of evolution and holder of PHd in genetics before DNA would insist on something about biodiversity from mutations without knowing the algebra of the holy trinity of evos. Shouldn’t that rather be attributed to De Vries instead?
What led them “to postulate” is somewhat complicted. Take Fisher for instance, here on the relation to thermodynamics:
(Structure of Evolutionary Theory by SJ GOULD page 512)
Now if Gladyshev is correct (I have a copy of this paper here) then this is incorrect as there is supposed by Georgi to be both a within species and a without series law ("Note that each type or species of organism is characterized by its own average life-span value for each respective hierarchy. However, series (5.1), is observed for each species of organism(page 61)).
Nowthen, if one replaces “equilirbiurm” with “environment” (if one doesnt then I cant really follow you here as we are left with a standard temperature and pressure environment the skein boundary between ourselves and whatever is outside) then indeed we can see what is leading Gladyshev to postulate the likes of Fisher and this explains how Darwin could get the pangene (regardless of which side of the Chanell ones views our wake from) wrong but I do not see how it is supposed to relate to diversity.
This has to be something between the species and the clade.
So when you ask what is the difference between Wright drift and Kimura neutural one has to recognize that there are many potential causes of drift that are not simply chance changes of DNA. Small populations sizes for one instance otherwise. Kimura used the situation between Fisher and Wright to argue that biologists were not recognizing the small good enough. If we see that the full differential referred to by Lewontin is actually an issue of equilibrium (a closed vs and open vessel of water etc) and not an individual under Scottish economics vs a peasen in Russia, no matter the science then indeed this difference can can be made clearer.
I will show something more along these lines by writing about the Russian
Lomonosov
Mikhail Lomonosov - Wikipedia (becareful with wiki as the actual papers I read, Lomonosov was using phlogistin as extant)
later in the thread on time.
EvC Forum: Is time merely a concept?
I think I understand what Darwin was trying to say about increases and this could occur by osscilation (so many wedges into the nair same spot on the surface (across the seasons)) rather than progression (of the Earth around the Sun (Gould always held dear to Darwin's statement that he (DArwin) 'saw no reason for progressive development in life') no matter the rotation but I am not sure what you mean to have had Darwin say.
Is is simply a matter of my not reading more of your posts?
Edited by Brad McFall, : spelling

This message is a reply to:
 Message 113 by Elmer, posted 12-11-2007 12:08 PM Elmer has replied

Replies to this message:
 Message 118 by Elmer, posted 12-11-2007 11:15 PM Brad McFall has replied

  
Brad McFall
Member (Idle past 5032 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 123 of 140 (440345)
12-12-2007 6:17 PM
Reply to: Message 118 by Elmer
12-11-2007 11:15 PM


Re:the same question
Are you saying that Pangenesis is Lamarckian or French?

This message is a reply to:
 Message 118 by Elmer, posted 12-11-2007 11:15 PM Elmer has not replied

  
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