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Author Topic:   MACROevolution vs MICROevolution - what is it?
CRR
Member (Idle past 2243 days)
Posts: 579
From: Australia
Joined: 10-19-2016


Message 286 of 908 (817017)
08-14-2017 10:23 PM
Reply to: Message 15 by RAZD
02-15-2007 4:11 PM


Re: The place of SPECIATION in MACROevolution
RAZD writes:
We can use ring species, such as the Asian Greenish Warblers (Phylloscopus trochiloides) to demonstrate that it doesn't take much difference to create a behavior barrier to mating: ... A modest change in plumage and mating song and there is no breeding behavior between the two populations.
Jerry Coyne has said that there are no ring species. Perhaps he didn't know about the Asian Greenish Warblers or perhaps their failure to interbreed has been exaggerated.
This could be a good example of why we should not equate speciation with macroevolution.
Other examples could be Lake Malawi cichlids that don't interbreed in the wild but do interbreed in captivity. Some butterflies exhibit similar behaviour.

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PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 287 of 908 (817018)
08-14-2017 11:54 PM
Reply to: Message 286 by CRR
08-14-2017 10:23 PM


Re: The place of SPECIATION in MACROevolution
That's a misrepresentation. Jerry. Coyne certainly accepts that what he would probably term species complexes exist. So far as I can tell he doesn't like to call them ring species because he thinks it is an over-simplified view and that geographic distance isn't a very important factor in their formation.

This message is a reply to:
 Message 286 by CRR, posted 08-14-2017 10:23 PM CRR has replied

Replies to this message:
 Message 288 by CRR, posted 08-15-2017 12:01 AM PaulK has replied

  
CRR
Member (Idle past 2243 days)
Posts: 579
From: Australia
Joined: 10-19-2016


Message 288 of 908 (817020)
08-15-2017 12:01 AM
Reply to: Message 287 by PaulK
08-14-2017 11:54 PM


Re: The place of SPECIATION in MACROevolution
Here's what Jerry Coyne said;
quote:
There are no ring species
TRIGGER WARNING: Evolutionary biology.
A while back, when I said in the comments of an evolution post that there were no good ring species, a few readers asked me what I meant by that. What about the salamander Ensatina eschscholtzii? Or seagulls in the genus Larus? Aren’t those good ring species? My answer was that those had been shown not to be ring species in the classic sense, but there was still one species that might be a candidate: the greenish warbler Phylloscopus trochiloides around the Tibetan Plateau.
But now that one, too, has been struck off the list of ring species, leaving no good cases.
(So he did know about the greenish Warbler)
I don't know what his opinion about "species complexes" is, or even what that means.
Edited by CRR, : No reason given.

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 Message 287 by PaulK, posted 08-14-2017 11:54 PM PaulK has replied

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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 289 of 908 (817021)
08-15-2017 12:10 AM
Reply to: Message 288 by CRR
08-15-2017 12:01 AM


Re: The place of SPECIATION in MACROevolution
You do realise that that quote supports my point ? That he's only denying that the examples fit the "classic sense" of ring species ?
And if you didn't know that "species complex" is the more correct term I don't think you are in any position to judge exactly what Coyne means.
And you obviously hadn't bothered to read the whole article where he explains his objection to the common example of the Ensatina salamanders:
Based on these results, everyone has now concluded that the formation of this ring involved sporadic and important episodes of geographic isolation between populations, so it’s not the classic continuous gene flow scenario involved in making a ring species.
Edited by PaulK, : No reason given.

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 Message 288 by CRR, posted 08-15-2017 12:01 AM CRR has not replied

  
Faith 
Suspended Member (Idle past 1445 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 290 of 908 (817022)
08-15-2017 2:14 AM
Reply to: Message 282 by PaulK
08-14-2017 11:52 AM


Re: Evolution has a built-in stopping point
we are talking about a program described in Dawkin's The Blind Watchmaker - a book that makes it quite clear that the culling of variety by natural selection is an essential part of evolution -
But the implication of the genetic loss by selection is overlooked, as if you could cull indefinitely and not deplete genetic diversity.

This message is a reply to:
 Message 282 by PaulK, posted 08-14-2017 11:52 AM PaulK has replied

Replies to this message:
 Message 292 by PaulK, posted 08-15-2017 2:26 AM Faith has replied
 Message 296 by CRR, posted 08-15-2017 3:34 AM Faith has not replied
 Message 303 by Taq, posted 08-15-2017 10:50 AM Faith has replied

  
Faith 
Suspended Member (Idle past 1445 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 291 of 908 (817023)
08-15-2017 2:23 AM


About "ring species," they illustrate how a small number of individuals migrating to a new location is all it takes to develop a new population with new characteristics from a new set of gene frequencies. There doesn't have to be loss of interbreeding to make this simple point, so there doesn't have to be speciation. It's messy if you take into account hybrid zones and resumed gene flow here and there but the overall picture ought to still be pretty much intact.
It should also demonstrate reduction of genetic diversity from population to population, at least certainly by the last population in the ring. The point is that these populations illustrate evolution, phenotypic change from population to population, and they should demonstrate enough loss of genetic diversity o make my point that you have to run out of the fuel for evolution itself eventually.
Edited by Faith, : No reason given.

  
PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 292 of 908 (817024)
08-15-2017 2:26 AM
Reply to: Message 290 by Faith
08-15-2017 2:14 AM


Re: Evolution has a built-in stopping point
quote:
But the implication of the genetic loss by selection is overlooked, as if you could cull indefinitely and not deplete genetic diversity.
But of course you can cull indefinitely so long as you have new variations arriving.
There's no implication being ignored. You're just very obviously wrong.

This message is a reply to:
 Message 290 by Faith, posted 08-15-2017 2:14 AM Faith has replied

Replies to this message:
 Message 294 by Faith, posted 08-15-2017 2:31 AM PaulK has replied

  
Faith 
Suspended Member (Idle past 1445 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 293 of 908 (817025)
08-15-2017 2:28 AM
Reply to: Message 284 by dwise1
08-14-2017 9:00 PM


Re: Evolution has a built-in stopping point
Whatever it was that Dawkins came up with some years ago that illustrated how cute little stick creatures move and change continuously from one form to another.

This message is a reply to:
 Message 284 by dwise1, posted 08-14-2017 9:00 PM dwise1 has replied

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Faith 
Suspended Member (Idle past 1445 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 294 of 908 (817026)
08-15-2017 2:31 AM
Reply to: Message 292 by PaulK
08-15-2017 2:26 AM


Re: Evolution has a built-in stopping point
But of course you can cull indefinitely so long as you have new variations arriving.
First, they don't keep arriving, even according to establishment descriptions of how mutations occur; beneficial mutations are extremely rare.
Second, if they did keep arriving they would defeat the purpose of the selection, and you could never get an identifiable variety or species.

This message is a reply to:
 Message 292 by PaulK, posted 08-15-2017 2:26 AM PaulK has replied

Replies to this message:
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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 295 of 908 (817027)
08-15-2017 2:41 AM
Reply to: Message 294 by Faith
08-15-2017 2:31 AM


Re: Evolution has a built-in stopping point
quote:
First, they don't keep arriving, even according to establishment descriptions of how mutations occur; beneficial mutations are extremely rare.
That's a major non-sequitur. The frequency has nothing to do with whether they keep coming. Mutations will keep coming and a small proportion will be be beneficial. But neutral mutations will do - or even mildly detrimental mutations - any variation that could become beneficial in the future.
quote:
Second, if they did keep arriving they would defeat the purpose of the selection, and you could never get an identifiable variety or species.
By which you only mean that it would defeat your argument. Selection has no purpose and certainly not the purpose of keeping a species in eternal stasis. Evolution is about change. It is because mutations keep arriving that evolution has occurred - from the earliest primitive life to the species we see today. If that is what you call "defeating the purpose of selection" then that's just your view. It certainly doesn't go against the role of selection in evolutionary theory - just the opposite.

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 Message 294 by Faith, posted 08-15-2017 2:31 AM Faith has not replied

  
CRR
Member (Idle past 2243 days)
Posts: 579
From: Australia
Joined: 10-19-2016


Message 296 of 908 (817031)
08-15-2017 3:34 AM
Reply to: Message 290 by Faith
08-15-2017 2:14 AM


Re: Blind Watchmaker
a program described in Dawkin's The Blind Watchmaker
There are 2.
quote:
He [Dawkins] demonstrates this by the example of the weasel program. Dawkins then describes his experiences with a more sophisticated computer model of artificial selection implemented in a program also called The Blind Watchmaker, which was sold separately as a teaching aid (open source implementations are currently available, as are more advanced versions of the idea).
The Blind Watchmaker - Wikipedia

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Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 297 of 908 (817034)
08-15-2017 7:43 AM
Reply to: Message 270 by Faith
08-14-2017 10:24 AM


Re: Evolution has a built-in stopping point
Faith writes:
... in order to get new varieties or races or breeds or species the genetic material for other varieties must be reduced, and completely lost in some cases.
This is as untrue as it has ever been.
I brought this up because the necessary genetic loss is never acknowledged in discussions of evolution,...
That's because genetic loss isn't necessary.
Evolution has a built-in stopping point
Where?
--Percy

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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 298 of 908 (817035)
08-15-2017 8:00 AM
Reply to: Message 297 by Percy
08-15-2017 7:43 AM


Re: Evolution has a built-in stopping point
I hope that you mean that there is no overall loss, Percy. Certainly alleles are removed from the population - fixation of an allele is, by definition, the loss of all others (although by the time it happens there may well be many variants). It's just that mutation increases variation is overall there is balance (in the species that survive).
And I would expect a species formed by the rapid allopathic speciation expected in PE to have less genetic diversity than the parent species (quite likely less than the founding population, IMHO)

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 Message 297 by Percy, posted 08-15-2017 7:43 AM Percy has replied

Replies to this message:
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dwise1
Member
Posts: 5930
Joined: 05-02-2006
Member Rating: 5.8


Message 299 of 908 (817040)
08-15-2017 10:24 AM
Reply to: Message 293 by Faith
08-15-2017 2:28 AM


Re: Evolution has a built-in stopping point
Faith writes:
DWise1 writes:
Faith writes:
I brought this up because the necessary genetic loss is never acknowledged in discussions of evolution, and the computer simulation models perpetuate the same wrong idea of an unimpeded series of changes from microevolution to macroevolution.
None of which is true. Could you please name some of these computer simulation models that you are referring to?
Faith writes:
Apparently even when they take "selection" into account they fail to represent this fact.
Any model describing or simulation evolution which does not take selection into account could not work.
Again, what computer simulation models are you talking about?
Whatever it was that Dawkins came up with some years ago that illustrated how cute little stick creatures move and change continuously from one form to another.
I asked a serious question and your reply is to bullshit us? And you wonder why nobody can take anything you say seriously.
There is a misconception that the amount of change in a phenotype is proportional to the amount of change in the genotype; ie, that a large change in the phenotype requires a large change in the genotype and that a large change in the genotype results in a large change in the phenotype while a small change in the genotype results only in a small change in the phenotype. That is not true, so Dawkins wrote Biomorphs to demonstrate that small changes in the genotype can result in large changes in the phenotype while large changes in the genotype can result in little or no change in the phenotype.
Biomorphs does not simulate evolution! Rather it illustrates development, the use of a genotype to generate a phenotype. Since it does not simulate evolution, it does not need to include selection but rather leaves it to the user to provide artificial selection to select a biomorph to be the parent of the next generation. For that matter, including selection in the program would present problems for the program itself (ie, would require defining an environment and how the phenotype of the organisms would interact with it for selection to work) which in no way whatsoever presents problems for evolution. At the bottom of my MONKEY page I discuss this problem and mention and briefly describe two programs that do implement selection.
Similarly, WEASEL does not even attempt to simulate evolution and explicitly was not intended to. Rather, it demonstrates the difference in performance of two different methods of selection: single-step selection (abysmally poor performance) which creationists falsely claim evolution uses, and cumulative selection (extremely effective) which is based on how selection in evolution works. That is what it was intended to do and that is what it does do. It was never intended to simulate evolution.
Since neither program was ever intended to simulate evolution, naming them to support your claims is completely false. Shouldn't you try to learn something about the things that you want to use to support your claims before you actually use them?
From the bottom of At the bottom of my MONKEY page:
quote:
Working on a project to more fully simulate evolution would be interesting, if I had the time. In such a project we would need to define an environment, phenotypes that would interact with that environment as they try to survive, genotypes that would direct the development of those phenotypes, and rules for the mutation of those genotypes.
The problems in developing such a simulation are considerable. All of these elements would need to be as realistic and as free from interference as possible. The criteria for fitness should not be predetermined arbitrarily but would have to come directly from the environment and the organisms' interaction with that environment. The embryonic development from genotype to phenotype should follow regular rules which could be arbitrary to some extent, but the phenotypes produced should not be predetermined, but rather be the result of the expression of the genotypes -- a software example of this is Dawkins' Biomorphs2. The mutation of the genotypes should be the easiest part of the project, once the genotypes have been defined. Of course, one of the greater problems would be how to evaluate the simulation; if we allow the model to be too abstract then the resultant environment and "organisms" could be so alien to us that we could not make any sense out of it.
The closest that I have seen programs come to simulating selection based on the interaction of an organism with its environment are TBUGS3 and Dr. Ray Thomas' TIERRA4.
In the meantime, I would still like to hear ideas for programs to simulate evolution and, if I should ever have to time to attempt such a project, I would definitely need ideas to work with. Of course, as I tell people who try to model evolution with single-step selection (like Michael Denton), we have to keep in mind just what we are trying to model.



FOOTNOTE 2:

In the second half of the third chapter of The Blind Watchmaker, Dawkins describes a kind of computer game they had written to illustrate aspects of embryonic development. From that link:

The program displayed a two dimensional shape (a "biomorph") made up of straight black lines, the length, position, and angle of which were defined by a simple set of rules and instructions (analogous to a genome). Adding new lines (or removing them) based on these rules offered a discrete set of possible new shapes (mutations), which were displayed on screen so that the user could choose between them. The chosen mutation would then be the basis for another generation of biomorph mutants to be chosen from, and so on. Thus, the user, by selection, could steer the evolution of biomorphs. This process often produced images which were reminiscent of real organisms for instance beetles, bats, or trees. Dawkins speculated that the unnatural selection role played by the user in this program could be replaced by a more natural agent if, for example, colourful biomorphs could be selected by butterflies or other insects, via a touch sensitive display set up in a garden.

The book's appendix included an order form for that program. However, at the time it only existed for the Mac, which I have never owned, so I wrote my own version in Turbo Pascal to run in CGA graphics mode on MS-DOS. The program has since been ported to Windows and there exist open source versions.





FOOTNOTE 3:

Actually, only I call it TBUGS, since I had written it in Turbo Pascal (hence the "T" in TBUGS). It was based on an article I read in Scientific American, which is described in Dewdney's BugWorld, a software project page:

In 1989, A.K. Dewdney wrote an article in Scientific American entitled "Simulated evolution: wherein bugs learn to hunt bacteria" as a part of the "Computer Recreations" column (May, pp. 138--141). The ideas in that article were included in his book Turing Omnibus (1989).
The idea described in these works is a very simple artificial life experiment. A tauroidal landscape houses moving agents (which we will call "bugs") and immobile food elements ("bacteria") for the agents. The bugs are incapable of sensing their environment, but they do make a kind of "choice" regarding the direction they move. This choice is made by a simple distribution across six different discrete turning choices, defined by a set of genes. Bugs gain energy when they eat bacteria and burn energy when they move; however, a bug that runs out of energy will die (be removed from the simulation), and a bug that has sufficient energy and age will divide into two nearly identical copies. At the start, the bugs "jitter" around, turning randomly; however, they will often eventually evolve to glide around the world, scooping up bacteria in their path.

That page includes a ZIP file containing the source code for a MASON applet -- again with the Macs! Googling on the article title, there's a page to buy a PDF of the article from Scientific American. There are also several programs based on the article, such as BugSim.
Basically, you can set up the environment with different rules for how the food elements grow; eg, food grows fast, food grows slow, food only grows in one area, etc. When the bugs reproduce by fission (one bug having eaten enough becomes two), the new bug's genes can be mutated. Since the genes control how they move, the new bug could develop new movement behavior. Then how the food grows determines which movement behavior works the best and soon all the bugs have that behavior since the ones that didn't had starved and died off. If food grows uniformly, then you'll have "cruisers" that just move in a straight line to where there's more food (their "world" has wrap-around, so when a bug leaves one side of the screen it reappears on the opposite side).
If food only grows in one area, then you get "twirlers" who move in tight circles in order to stay where the food is. I seem to recall (it has been nearly three decades, after all) that how fast the food grows also affects how fast the bugs move. And so on.





FOOTNOTE 4:

Dr. Thomas Ray's TIERRA was rather interesting -- go to that Wikipedia article for more information and for the link to the
TIERRA Home Page. Its organisms are virtual computers which fed on computer resources (ie, memory, processing time). Each consisted of a short program which enables it to use resources and to reproduce. Two interesting results of the experients were:

  1. The co-evolution of parasites and hosts

  2. Parasites are entities that have lost the ability to reproduce on their own, so somewhat like a viruses (viri) they infect healthy entities in order to use their hosts' resources in order to reproduce. In response to the parasites, some hosts evolved code to resist a parasite attack and some hosts even evolved strategies to exploit the parasites, thus becoming a kind of hyper-parasite.
  3. Evolving programs deemed by humans to be impossible

  4. The humans developing TIERRA worked out the original code for the entities to reproduce. In the process, they determined the minimum size that a program could be and still enable reproduction; an entity with a smaller program simply could not reproduced and would eventually die an evolutionary dead end. But then some entities developed program techniques that the humans had never dreamed of, had thought to be impossible. With these novel techniques, entities with programs maybe half the size of the "smallest possible working program" were able to reproduce and also, as I recall, make more efficient use of resources. When you read the documentation, look for "unrolling the loop."


Remember that those properties evolved on their own and were not planned by the human experimenters in any fashion.



This message is a reply to:
 Message 293 by Faith, posted 08-15-2017 2:28 AM Faith has not replied

  
dwise1
Member
Posts: 5930
Joined: 05-02-2006
Member Rating: 5.8


(1)
Message 300 of 908 (817041)
08-15-2017 10:28 AM
Reply to: Message 293 by Faith
08-15-2017 2:28 AM


Re: Evolution has a built-in stopping point
Faith, you again tried to avoid the main question. From Message 284:
DWise1 writes:
Let's use a different example to state your position:
quote:
Automobiles get their propulsion from their engines, but they are always subject to friction. Friction inevitably slows them down to a halt. Therefore, it is impossible for automobiles to move.
The only way for that model to be true is if you only take friction into account and not the car engine. That is what we keep seeing you do with this argument.

This message is a reply to:
 Message 293 by Faith, posted 08-15-2017 2:28 AM Faith has replied

Replies to this message:
 Message 301 by Faith, posted 08-15-2017 10:30 AM dwise1 has replied

  
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