Is there "Progression" in Evolutionary Theory

In Biological EvolutionIn a Biblical thread this exchange came up:

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Evolutionist do not use progression as more than a series of footprints. In TOE, progression is simply a description of path. It does not apply, and never has applied to anything more than that. Evolution is not from worse to better, smaller to bigger, bigger to smaller, or any other such nonsense. Those that survive long enough to reproduce, suceeded.
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So, are you saying that Amoeba to Man is not progression? Amoebas had no intelligence. Common ancestors to ape-like creatures were considered to have "less" intelligence than man. Man is considered to be much more intelligent. This is not progression?

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Since this is a common misunderstanding in all camps I think we can discuss it separately.

Thread moved here from the Proposed New Topics forum.

Evolutionary progress is a movement from adapted to better adapted. The morphological changes that contribute to adaptation are not directly part of the progress, but are instead a solution to the problem of increasing adaptation. IOW, progress from smaller to bigger, simple to complex, etc. are secondary to the primary concern which is being better adapted to the environment.

There are a couple of subtlies to get straight here.One is an assumed definition of "progression". If we think that bigger, smarter, faster, or whatever else is "better" then we might see progression.However, in evolutionary theory there is only relativly more able to survive at a given time, in a given enviroment. Bigger is not always better, faster is not always an advantage and it's not clear that smarter is either.Second is looking at a very selective portion of all living things and looking at the result of the evolutionary pathways.Today after 3.5 Gyrs of evolutionary change life is still overwhelmingly bacterial or simpler. By mass, individual count, number of species or any other measure of surviving succcess you want to use it is, as Gould says in "Full House" the Age of Bacteria. Always has been always will be.The rest of life is just a minor statistical bump on the charts. There has been, at most, a small amount of "progress" if you carefully define progress to be less bacterial.What we do have is a movement in the [b]maximum[b/] size, complexity or what have you. While the average creature is still a bacterium the most -- whatever you pick -- is not still at the bacterium level.As is also described in "Full House". If life started at the stage of about a bacterium then it almost has to move the average and certainly the most "complex" somewhat away from that. The only other direction to move in would be total extincition.In the example given if what we call intelligence is defined as being "progression" then there has been progression. But that is just an historical accident. Evolution happened to take one branch of life through a rapid increase in brain size and intelligence. That worked for those forms of life. It would not be progression in a lot of environments that couldn't support a large, expensive brain.It may yet prove to be a dead end.If you stand back and look over the entire evolutionary history of life you will see lots of different branches moving in lots of different directions. Most have stayed near the base (almost all in fact). A few have moved a bit farther from that base and maybe temporarily farther.

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However, in evolutionary theory there is only relativly more able to survive at a given time, in a given enviroment. Bigger is not always better, faster is not always an advantage and it's not clear that smarter is either.

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Which I think is the first of the subtlies. "Better" is defined by the environment and not by any other measure. Being the crazy humans we are, we often look at smarter, bigger, faster as being "better" but we are ultimately not the ones that decide the species ability to survive in any given environment.

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Second is looking at a very selective portion of all living things and looking at the result of the evolutionary pathways.

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Yes, your explanation of the "Age of the Bacteria" is a very important point. Also, it is important to point out that the bacteria we see today have gone through 3.5 billion years of evolution. What is amazing to me is even though bacteria rely on a relatively small genome they are able to respond to environmental cues quickly and appropriately through ingenious use of DNA transcription control mechanisms. Even though these buggers are small, they really are quite complex in both their construction and their ability to respond to the environment. So even the smallest forms of life can be considered quite complex and well adapted.

It is pretty much settled that while evolution can produce what we could call "progress" it does not automatically do so.The folowing factors are at work1) When you start at the bottom, the only way is up. If life is about as simple as it can get beneficial changes will almost always involve added complexity. Of course it is also possible - perhaps even likely - that a species can reach a level of complexity where it is unlikely that additional complexity will be helpful.2) Simplifications which disable useful features will usually cause a loss of fitness and be selected out. If a species' environment should change so that the cost of complex features outweigh the benefits they do tend to be disabled or lost - either by drift or in some cases through positive selection. Parasites tend to simplify - and "blind cave fish" are a well-known example of loss of function.Of course, complexity - while closer to what we think of as progress than the evolutionary concept of fitness - is still not quite the same thing.So I would say that there can be a slight trend to "progress" - but one that can easily be overwhelmed by other factors - certainly it would be wrong to assume that any one species was "progressing" without examining the situation closely. However it is false to say that evolutionary change is automatically progressive. It can easily be neutral so far as "progress" is concerned or even regressive.

You might like to look at Caporale's work -a s well as that of other researchers. _Darwin in the Genome_ is a popular introduction, but really only a starting point.

I think this is one of my rantings. to which someone replied so I feel I should at least try to explain my ramblings.First there's the question "So, are you saying that Amoeba to Man is not progression?" It is progression, if you mean a description of the steps, the path. But it also could not have gone any other way. It is impossible, or at least hard to imagine, life that is simpler than a single celled organisim.Then the next question was, "Common ancestors to ape-like creatures were considered to have "less" intelligence than man. Man is considered to be much more intelligent. This is not progression?"First, there is nothing about being more intelligence that makes it better or worse except from our personal perspective. From the Evolutionary perspective, humans are still way to recent to say whether it will rank as one of the more successful critters. We certainly have not lasted as long as the dinosaurs, and no where near as long as sharks, turtles, bateria, viruses or even grass.There is also the very real risk that the very trait, intellegence, might be the factor that leads to human extermination. Afterall, what determines success or failure from the TOE is living long enough to reproduce.Evolution is simply a history of which critters survived. It is not directed, it is not a progression from lessor to greater, worse to better. It is history of which critters survived. There is no goal, except to live long enough to reproduce.

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Aslan is not a Tame Lion

This poses an important question - is there such thing as "regressive" evolution?Blind cavefish are an excellent point of discussion, since many consider their evolutionary history as "regressive" (which presumably is the opposite of "progress").However, if you look beyond the loss of eyes and pigment, the cavefish have "progressed" in other traits - they have enhanced taste sensation, more efficient metabolism, and improved jaws for hunting relative to their surface relatives. Interestingly, it is believed that the changes to the jaw that have improved hunting success were only possible after developmental constraints imposed by eye structures were lifted.Also, loss of eyes in of itself could be considered "progress" if they are no longer needed, since less energy would be expended for non-necessary structures during development - in this case the result is positive progression in fitness(not neutral or regressive) even though a human's first thought might be "loss of eyes is a bad thing". Though it may be a matter of semantics, I will disagree with you on this point, especially since you imply that "progress" is more akin to "fitness" than "complexity". Regressive changes, as determined by the environment, would be selected against - thus truly regressive evolution cannot occur.This message has been edited by pink sasquatch, 08-13-2004 06:39 PM

Evolution always favours increases in fitness - but fitness is always relative to environment and poorly linked to our ideas of progress.My use of the term "regression" is simply to say that evolution can produce changes which are the reverse of what we would call "progress". And that, after all, is one of the key points I am trying to get over.

There does seem to me to be a need to discuss nonadaptive traits better than the elder evolutionists have done.Gladsyhev's view disproves Carter's idea of Batesonian criticism of natural-selection theory, if true, and if so- shows that there can be abstractable selection on the genotype. This equilibrium view needs to be quantitative worked into Wright's BALANCE but still it seems that for anti-creationist views we dont have this understanding as of yet.see info by means of:
The work here at EVC does go in this direction towards falsification of Carter's AHUNDREDYEARSOFEVOLUTION(p134)
"This new conception of the mode of action of the genotype in the body destroys the whole force of Bateson's criticism of the natural-selection theory. Selection is exerted on the organism's body, not directly on the hereditary material, the genotype; it si the characters as expressed in the body that come directly under the influence of selection, and in discussing selection we must consider its effect on them. If in a race of animals some character such as large size is advantageous, those individuals that have this character developed above the mean...."

Here is an example that is less technical just so some of our creationist friends can understand.I recently saw a program on the discovery channel about snakes. At one point, they were talking with some biologists about rattle snakes in certain areas. The biologists said that it is getting harder and harder to find rattle snakes that actually rattle.Why? Mankind has become a selective force the last 200 years or so. There are people that actually seek out and kill every rattle snake they could find, which usually are the loud ones. Because the rattle snakes that rattle give their positions away too easily, they are being killed off before they could reproduce. The quiet ones now outnumber the loud ones.In other words, we have just observed a change in allele frequency because of a selective pressure we call man.The question is are the quiet rattle snakes more "progressed" than the loud ones?Rattle snakes started rattling to inform animal of their presence so that they wouldn't be stepped on. This is a rather good trait especially when you are living in a dessert environment. So, you could say that the rattle snakes that rattle were more adapted to their environment (before man started killing anything that rattles).But now, the rattle snakes that are completely quiet are the ones that are better adapted to their environment.Coincidently, the quiet ones are a lot more dangerous than the loud ones for obvious reasons.

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The Laminator
For goodness's sake, please vote Democrat this November!

The vast, vast majority of the Earth's biomass has been and continues to be organisms far simpler than the ameobas you mentioned. Complex organisms are far, far outweighed and outnumbered by the simplest forms of life.Isn't this not progression? Except for some statistical outliers it sounds to me like evolution has found very little usefulness in increased complexity.

[quote]This poses an important question - is there such thing as "regressive" evolution?[/qutoe]I guess you could qualify it. It might be more accurate to say that there is regression within evolution. Evolution itself simply states that there will be adaptation to the environment, which could either be "progressive" or "regressive" in a subjective sense. However, I would never call it "devolution" as many would claim.

Progression/regression are not even relevant to evolution.Evolution is a kind of target-tracking, or set-point
control type function.Q: 'Is amoeba to man not progression?'
A: Only if you want it to be.What is there about a human that makes it more 'progressed'
than an amoeba?Doesn't the amoeba perform all necessary life-functions with far
fewer input resources and less energy expenditure than a human?Doesn't that sound like a better organism from the PoV of
survival of the species?The whole concept of putting 'progression' into evolution
pre-supposes that man is top of the heap ... and says
more about man's arrogance than evolutionary process or
history.