Remember; Evolution is NOT a Theory. Natural Selection is.

[benburch]

To be a theory, an assertion must be at least in principle disprovable. Evolution no longer is disprovable; We know for fact that species change over time and that changes are inherited.

What still is a theory is the exact mechanism that selects what changes prosper. It is clear to many that classical Darwinian Natural Selection is not a complete answer.

Remember that when people next try to assert that Evolution is a theory; They are even more ignorant than they look!

[Dr Ron]

1. Theory misunderstood

The real problem here is that many people don't understand the difference between theory as used in science and by the general population.

[supernova]

9. Thank you

this mix up in meanings happens here at DU a lot too.

[yellerpup]

2. Thanks very much for this...

I argue with someone almost daily about evolution being fact. You comment on natual selection will help a great deal.

[redqueen]

3. Well there's a very valuable distinction.

Not that it'll make a lot of difference to the fundie morans who want this to be a Christian nation.

[LongTomH]

4. The problem with arguing with creationists

is that, like most people in America, they're scientifically-iiliterate. Only about 5% of the U.S. population is really literate about science, and that figure drops to 3% for Hollywood screenwriters.

[aneerkoinos]

5. *sigh*

Go read your Popper again, what falsifiable means. Strictly speaking, there are no scientific "facts", only observables (= data) and theories. If evolution is not a theory (which it is), it is not science. For chrissakes, even TIME is a theory!

[BurtWorm]

7. Popper doesn't have the last word on what a theory is, does he?

The point of the original post, I think, is that evolution is an observable phenomenon. It's well established by other observables. How evolution occurs, on the other hand, must be theorized.

[aneerkoinos]

14. Lets be carefull

First, of course Popper does not have the last word, and I bet he would be first to admit that.

Second, show me evolution! Yup, you can't. You can show me fossiles, even data from test tube populations from different times and show me the difference between those populations (cutting some corners here for brevity's sake), but observables are what is (more or less) directly perceivable, when deduction cuts in, it's a theory. Heck, time related causativity itself is not directly perceivable, it is a theory.

Science starts from admitting that besides observables (perceptions) there is only theories, and Popper tried to give some criteria for deciding which theories are scientific, which are layman's theories.

[BurtWorm]

15. Here's what Gould said about that.

I bolded his key point:

http://www.stephenjaygould.org/library/gould_fact-and-theory.html


...

Well, evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts do not go away when scientists debate rival theories to explain them. Einstein's theory of gravitation replaced Newton's, but apples did not suspend themselves in mid-air, pending the outcome. And humans evolved from apelike ancestors whether they did so by Darwin's proposed mechanism or by some other, yet to be discovered.


Moreover, "fact" does not mean "absolute certainty." The final proofs of logic and mathematics flow deductively from stated premises and achieve certainty only because they are not about the empirical world. Evolutionists make no claim for perpetual truth, though creationists often do (and then attack us for a style of argument that they themselves favor). In science, "fact" can only mean "confirmed to such a degree that it would be perverse to withhold provisional assent." I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms.

Evolutionists have been clear about this distinction between fact and theory from the very beginning, if only because we have always acknowledged how far we are from completely understanding the mechanisms (theory) by which evolution (fact) occurred. Darwin continually emphasized the difference between his two great and separate accomplishments: establishing the fact of evolution, and proposing a theory—natural selection—to explain the mechanism of evolution. He wrote in The Descent of Man: "I had two distinct objects in view; firstly, to show that species had not been separately created, and secondly, that natural selection had been the chief agent of change. . . . Hence if I have erred in . . . having exaggerated its power . . . I have at least, as I hope, done good service in aiding to overthrow the dogma of separate creations."

Thus Darwin acknowledged the provisional nature of natural selection while affirming the fact of evolution. The fruitful theoretical debate that Darwin initiated has never ceased. From the 1940s through the 1960s, Darwin's own theory of natural selection did achieve a temporary hegemony that it never enjoyed in his lifetime. But renewed debate characterizes our decade, and, while no biologists questions the importance of natural selection, many doubt its ubiquity. In particular, many evolutionists argue that substantial amounts of genetic change may not be subject to natural selection and may spread through the populations at random. Others are challenging Darwin's linking of natural selection with gradual, imperceptible change through all intermediary degrees; they are arguing that most evolutionary events may occur far more rapidly than Darwin envisioned.

[Karenina]

19. Stephen Jay Gould...

a brilliant mind and sorely missed...

[BurtWorm]

20. He died too young.

And so did Sagan. :cry:

[aneerkoinos]

21. Thanks

To be honest, I'm not a fan of Gould or any other polemical materialist.

>>> "fact" can only mean "confirmed to such a degree that it would be perverse to withhold provisional assent." <<<

So what makes fact different from theory is based on subjective evaluation. In other words, fact is a subclass of theory, a theory deemed so convincing that the popes of science strongly advice not to question.

Well, having dilettante's interest in Quantum Physics, I have no problems questioning one-directional arrow of geometric time (not to mention psychological time) and possibility of quantum processes being involved in macroscopic biological processes, so I reserve the right to question the premisses on which the usual materialistic notions of evolution are based, never mind what the popes say.

[BurtWorm]

23. It's clear you're not a fan of Gould. It doesn't surprise me.

Why question that humans evolved from older species? Because you didn't see the actual evolution?

Is it not possible to infer a fact from evidence? Or is every instance of induction mere theorizing? Do I have to have seen a fire burn a building down, for example, to take it as fact that a pile of smouldering boards and bricks I come upon was very probably a building that burnt down?

[aneerkoinos]

26. Call me a sceptic

>>> Why question that humans evolved from older species? <<<

Why not? Science is about questoning. Doesn't all philosophy start with wondering, with radical scepticism?

However, your question is not the point of my scepticism, even though I'm fully open to the possibility that every quantum leap from *now* to *now* rewrites the whole causal history (including "evolution" and memory) and future of this Universe. On the more modest level of description, I'm sceptic about the purely materialistic models of evolution and open to the possibility of also macroscopic quantum processes being involved.

>>> Is it not possible to infer a fact from evidence? <<<

In the sense that Gould uses the word "fact", sure, why not. But don't call that inference unquestionable Truth.

>>> Or is every instance of induction mere theorizing? <<<

Theorizing yes, mere not. Why badmouth theorizing? As if we could NOT help theorizing all the time!

>>> Do I have to have seen a fire burn a building down, for example, to take it as fact that a pile of smouldering boards and bricks I come upon was very probably a building that burnt down? <<<

"Probably" is good word. How probably, deciding that with plausible accuracy requires a lot of data and calculation power plus a sound theory. ;)

[BurtWorm]

27. You're probably a hair-splitter.

And that's a fact. ;)

Seriously, I'm too much of a materialist to have problems with Gould's (and Sagan's and Dawkin's) notion of fact. I'm interested in what *really* happened, which in the case of evolution is this: humans evolved from an older species, which evolved from an older species, etc. We know this because of the genetic evidence, as well as the fossil evidence. And because of plain induction. If humans did not evolve from an earlier species, where did they come from? You can answer that question imaginatively if you'd like, but there is a difference between philosophical speculation and scientific reasoning.

[aneerkoinos]

31. How modest!

If we had stuck to splitting mere hair, we would have never got to splitting atoms and even smaller stuff!

What is a fact is that metaphysical materialists can stay that way and hold on to their cherished beliefs only by showing contempt at what they call philosophical hair-splitting! ;)

>>> philosophical speculation and scientific reasoning <<<

Indeed, the other is mere speculation, the other is serious grown-up stuff!!! ;)

Perhaps we can at least try to avoid such rhetorically loaded verbiage? I did semantics and rhetorics in university and if you want to win points by such means, you have to do much better. :)

Seriously, what should be obvious is that reasoning is possible only on given premisses, either consciouss "contracts" or unconsciouss "unquestioned beliefs". And exposing those unquestioned beliefs takes a joint effort of philosophy and all other fields of science, and can be often painfull because it's a "fact" that we are emotionally attached to our unquestioned beliefs, and because that exposing is seemingly a neverending process and such uncertainty is not something we are willing to easily accept.

[BurtWorm]

32. I am perfectly willing to accept uncertainty.

I am not quite so willing to accept speculating for speculation's sake.

If my question is "where do species come from?" I am asking a very specific question that entails your understanding what I mean by "species," for example. We can debate about what a species is, or if there is really such a hard and fast thing as a species when individuals are unique. We can debate about why this fossil may or may not be related to that one or to these living species. But if we disagree about the existence of the fossil, or get bogged down in irrelevant epistemological arguments, then we're talking about something other than the question "where do species come from?"

I'm sorry, but I can't operate that other way. You and creationists are free to talk amongst yourselves. If you discover that "where do species come from" really is a meaningless question, by all means, let me know! ;)

[aneerkoinos]

34. Bah

>>> You and creationists are free to talk amongst yourselves. <<<

What makes you think I would be interested to talking to creationists, other than to criticize their views? "With us or against us" - mentality with the conviction that there are only two camps? I hope and trust you can overcome that obstacle and talk to me, not the camp you imagine.


>>> I am not quite so willing to accept speculating for speculation's sake. <<<
>>> irrelevant epistemological arguments, <<<

Philosophy has all to do with observables and reasoning and nothing to do with idle speculation, aka sofistry. I believe I've allready shown that to engage in honest scientific quest for truth one cannot ignore the premisses of one's reasoning. What is idle and lazy and unscientific is ignoring the value of philosophical reasoning in exposing those premisses.


>>> "where do species come from" <<<

I thought I made myself clear but perhaps I didn't. On this level of examination I'd say from interaction between organisms and their enviroment. What I'm not convinced of is that the processes involved are purely materialistic, but think there may also be quantum-mentalistic processes involved (e.g something akin to Sheldrake's morphogenesis), that might offer better explanations to problems like sudden jumps. Satisfied?

[BurtWorm]

43. quantum-mentalistic processes.

In other words a designer.

What do you mean "interaction between organisms and their environment" are where species come from? They interact with their environment all the time. You mean if a cow interacts with a blade of grass it might transmogrify into some new species?

[aneerkoinos]

45. *sigh*

>>> In other words a designer. <<<

Define "designer", it's an empty word for me. And what did I just say about "us-and-them" camps?

>>> What do you mean "interaction between organisms and their environment" are where species come from? They interact with their environment all the time. You mean if a cow interacts with a blade of grass it might transmogrify into some new species? <<<

Please mr. Gestapo. Let's add the words 'populations' and 'change', which were implied the first time.

[BurtWorm]

47. And "quantum-mentalistic" is *not* an empty word for you.

:eyes:

So if a population of cows relates to blades of grass, it may transmogrify into a new species?

[aneerkoinos]

49. No

By "quantum-mentalistic" I refer to a group of theories and hypothesis attempting to solve the Body-Mind problem with quantum approach.

>>> So if a population of cows relates to blades of grass, it may transmogrify into a new species? <<<

Are you suggesting they may not transmogrify? But what if the cows don't obey you and keep on transmogrifying? :P :hi:

[BurtWorm]

51. Oh that makes SO much more sense.

:applause:

Thank you.

Now, back to the cows: I'm wondering how interacting with the environment leads these populations of organisms to change into new species? How about this idea? Some in the population of cows, it turns out, who share the same characteristics, like say, side to side jaw action, survive better in their relationships with blades of grass than those missing that trait. So the cows who share the successful relationship with their blades of grass pass on their side-to-side-jaw-action genes onto their calves while the ones who don't have that gene die out. Voila! Cow species transmogrifies!

Hey, maybe we are on the same page after all!

:toast:

[aneerkoinos]

53. *bows*

>>> Oh that makes SO much more sense. <<<

Thank you for asking, it's allways admirable to see a person openly admitting his ignorance and asking for enlightment. For answer, try this:
http://www.quantumconsciousness.org/
and Google for more. :)

>>> Hey, maybe we are on the same page after all! <<<

Given from beginning, but where did all those black stains come from??? :silly:

[BurtWorm]

54. By the way, would it matter to you if you found out Karl Popper said

of evolution that it is a "historical fact?" Would that make you inclined to agree with Popper about the factuality of evolution, or would it make you think Popper is misreading himself?

I ask because on my ride home last night, I happened by sheer coincidence to read (in a book called Tower of Babel by a philosopher named Pennock) that very assertion. Appearently creationists have been tricked into thinking Popper definitively dismissed evolution as a *theory* for its untestability, but they leave out that Popper famously admitted he'd made a mistake by not having all the evidence in front of him, so he changed his mind and gave it his blessing. But he also apparently gave his blessing to the "historical fact" of evolution in another late piece of writing. I don't have the exact reference, but I can get it. It was footnoted.

[aneerkoinos]

59. Well

I brought up Popper in relation to the curious notions about falsifiability in the OP, not to add Popper into the confusion about the triple (at least) meaning of "fact" ('Undeniable Truth', 'theory that should not be questioned' and 'observable data').

So, it would not matter to me if Popper in his Homeric lapse has added to the confusion.

[BurtWorm]

61. If only we were all aneerkosians, there'd be no controversy.

:evilfrown:

[aneerkoinos]

46. Designer

Here's what I think:

What "design" is, is just our conseptual projection over "Ding and Sich", a rather poor analogy IMHO.

In fact, I think any kind of -er or -or (desigER, creotOR or any independent cause) is just a conseptual (egocentric) projection. Think about this discussion we are having, how it evolves: are we two its designers or creators? I would say that it is obvious that there is discussion going on, a dialectic, but neither of us are (nor anybody else is)independent causes of this discussion, only participants in dialectic the origin of which is unknowable, a meaningless question.

Does this help to clarify my thinking?

[BurtWorm]

48. You'll have to tell me if it helps clarify your thinking.

;)

[aneerkoinos]

50. Yes please

It does, thank you very many! :)

[SlavesandBulldozers]

38. yes

and no.

:popcorn:

[benburch]

11. My professors used to discount Popper...

And so do I.

[aneerkoinos]

16. And so do I

Feuerabend is my man, but if you wan't to debate meanings of science, theory etc. without making fool of yourself, gotta know your basic Popper.

[JHBowden]

56. Try reading Putnam, Byrd, Psillos, etc.

Few working in the philosophy of science today believe Popper's ideas. Many scientific theories are not falsifiable. Mercury's orbit did not accord with Newton's theory of gravitation, but this did not falsify Newton's theories. Nor should it have. That's because scientific theories, if we examine them historically, are not falsified -- they are replaced.

[nonconformist]

6. Actually, it is a theory, a scientific theory

It's a semantic thing.

The problem is people not understanding what a scientific theory is. Gravity is a theory for cripes sake.

[BurtWorm]

8. Richard Dawkins, for one, calls evolution a fact.

So did Gould and Sagan. If nonscientists are confused, our confusion is caused by scientists.

[aneerkoinos]

12. heh

Yes, I agree that Dawkins, Gould and Sagan are confused! ;-)

[BurtWorm]

13. How do you know it isn't you who's confused?

Maybe they're using the term "fact" differently from you, non-conformist and Popper? :shrug:

[aneerkoinos]

17. Good question

:D:D:D:D

How does anybody? ;)


To be serious, my joking retort was not because of using term "fact" in its loose rhetorical meaning, but because I think all metaphysical materialists are confused! :)

[BurtWorm]

10. Remember, too, that evolution has nothing to do with the origin of life

but with the origin of species.

[bryant69]

18. That's the problem with this debate.

The real question that is driving it is unknown (and possibly unknowable) which is was there a creator or not? People who attack evolution see it (wrongly in my opinion) as a knock on the idea that we were created by a God (or Gods).

Bryant
Check it out --> http://politicalcomment.blogspot.com

[BurtWorm]

22. Evolutionists aren't interested in that question professionally.

They're only interested in the question of how species come into being, and why. They don't have anything to say about who or what created the cosmos or life, let alone why. The only reason they're in the debate is because creationists, many of whom feel threatened by evolution (because they believe it threatens their scriptural view of creation), are persistently trying to bring their theological arguments into the public school science curriculum.

[TahitiNut]

28. Actually, they're threatened by the implication that we're not the END ...

... of evolution. It's self-centered, narcisistic anthropomorphism on steroids! How dare anyone suggest that we're not PERFECT? How dare anyone suggest that we're still evolving? After all, God exists solely to show that humanity, as it currently exists, is the whole reason for all of Creation, right? :eyes:

[Hello_Kitty]

24. Yes and Darwin's book was called "Origin of Species"

Not "Origin of Life". An important distinction that foes of evolution theory fail to grasp.

[BlueIris]

25. Yes, thanks for giving the confused a reality check.

I self-deleted my own lengthy explanation about this in another thread earlier today, thinking no one really needed to read that.

To those who might want to know more about the difference between facts and theories, and also about the facts of human evolution, I recommend Stephen Jay Gould. His works are accessible, and if you find them too accessible, his articles can direct you to more scholarly purpsuts. I really encourage everyone to get and stay informed about the basics of science, so you can educate your friends, neighbors and children about this in our sad, New Dark Age.

[aneerkoinos]

30. More on facts and theories

We discussed this above at some length, but I'd like to add this:

Fact, in the sense that Gould uses the term, is political and rhetorical. It is scientific only to the extent it relates to the subjective assesment of the members of scientific community as to what is worth questioning and what is not (in Gould's words, what would be "PERVERSE" to question, a choise of word which raises a red flag here). This kind of political and rhetorical use of language only adds to confusion, and does not take science forward.

As we know, throughout the history of science the popes of science have been saying that it would be perverse to question this and that, and again and again those popes have been proved wrong. It was perverse to suggest relativistic time, like Einstain did. It was perverse to suggest that there are supraluminal causal relations, like QT did. Yet the EPR experiment proved a non-local, in other words transcendental codependency.

So every time any pope of science declares ex cathedra: Thou shalt not question!, don't take his word on it. See for yourself.

[BurtWorm]

33. Why should we take a pope of metaphysics word for it?

;)

[aneerkoinos]

35. Cause I says so!

:hi:

[KittyWampus]

29. I've Made This Point In DEFENSE Of Intelligent Design MANY Times

if you think it's just the Creationists and those abusing ID who are the only ones unable to make this distinction you are completely mistaken.

Yes, Darwin's Theory uses Natural Selection as part of the mechanism.

Intelligent Design does NOT dispute this.

Darwin's Theory also posits BLIND CHANCE as part of the mechanism... despite the fact that this has many serious flaws.

[ken-in-seattle]

36. ah the rub...

Intelligent design does not dispute this NOW. Not sine the supreme court threw out simple creation "science" The web site has changed at the discovery.org and purged all the mention of religion or biblical inspiration, but the same clows crawl out of the little car when it stops. The moonie doctorates in bio-chem and the moles that fund them are still hoping to fool the court into creating a loophole in legal precedent. That there are still some questions remaining in pockets of science under the umbrella (or big-top if you will) of evolution does not come anywhere near invalidating the theory.

Creationists make it sound as though a 'theory' is something you dreamt up after being drunk all night.
-- Isaac Asimov

The ID think tank is in downtown Seattle and used to be openly creationst even though the looked down on the young earth/ dinosaurs-missed-the-Ark fundies before their funding picture improved...

"Evolution by natural selection, the central concept of the life's work of Charles Darwin, is a theory,""It's a theory about the origin of adaptation, complexity, and diversity among Earth's living creatures. If you are skeptical by nature, unfamiliar with the terminology of science, and unaware of the overwhelming evidence, you might even be tempted to say that it's 'just' a theory. In the same sense, relativity as described by Albert Einstein is 'just' a theory. The notion that Earth orbits around the sun rather than vice versa, offered by Copernicus in 1543, is a theory ... Each of these theories is an explanation that has been confirmed to such a degree, by observation and experiment, that knowledgeable experts accept it as fact."
-- David Quammen, science author, in National Geographic.

[Guaranteed]

39. I think Quammen's right up until he compares

the Earth revolving around the Sun to natural selection. They're not on the same level. Natural selection is a sociobiological phenomenon. It's not like arithmetic. It does make use of chance, and thus it's kind of mathematical, but it's not exact, at all. It just doesn't always apply.

[BurtWorm]

44. What flaws?

[nothingshocksmeanymore]

37. Gravity is a theory. The day right wingers jump off cliffs to defy it,

I'll listen to their other attacks on science.

[SlavesandBulldozers]

40. can somebody explain to me the difference?

doesn't evolution inform, or infer, natural selection? I genuinely don't know the specifics of the distinction between the two. Isn't natural selection the observable benefit of evolution?

[Guaranteed]

41. Evolution is just the idea that species mutate into different

geno- and phenotypes. That's pretty well known to be true. Natural selection is Darwin's proposed mechanism by which species continually change their geno- and phenotypes over time.

[SlavesandBulldozers]

42. gotcha

thank you bullgooseloony.

[starroute]

52. Aren't these arguments just over the words "fact" and "theory"?

I don't see a dichotomy here -- I see a much broader spectrum of possibilities.

For example, it's a solid fact that things fall. We know it by personal observation. Those few things (like helium balloons) that do not fall under normal conditions will fall in a vacuum.

It's a theory, but a well-established one, that all physical bodies, from stars to dust motes, appear to be drawn towards one another to a degree proprotional to their masses and the distance between them. We rely on that theory all the time for exact mathematical calculations and it is extremely reliable.

But when you start asking about the nature of that attraction, you get off into pure speculation. Newton called gravitation a "force," but he and his contemporaries were puzzled by the aspect of attraction at a distance, which violated their assumption that all physical interactions should involve material objects bumping into one another.

Even today, gravity baffles us by its lacks of physicality. Unlike, say, electricity, it has no detectable particles to carry it, there is no way of shielding against it, and it can't be captured and stored in a bottle. Einsteinian relativity suggests that gravity doesn't really exist -- that it's all a matter of the bending of space -- but relativity's been around for a century and it doesn't seem to have settled the questions. The latest idea is that gravity may operate through higher dimensions, accounting for both its elusiveness and its weakness in our own three-dimensional reality. Or that if we can just find a "God particle" we may finally understand mass. Or whatever.


In the same way, the existence of living creatures is a fact. The existence of fossils is a fact. But beyond that, there are many different levels of theory.

On the simplest level, we can form classifications of living creatures based on appearance, behavior, and ability to interbreed. And -- though on the basis of appearance alone -- we can fit most fossils into that classification as well. This is a form of theorizing, and there are still disputes over such matters as whether flying foxes are really bats, but it's largely uncontroversial and taken for granted.

Going beyond mere classification, we can hypothesize that similarities among creatures are the result of descent from a common ancestor, with creatures that are more similar having a more recent ancestor in common, and that fossils are the remains of now-extinct members of this same family tree. That is the simplest form of the theory of evolution, and it is as solid and well-established as Newton's Law of Gravitation.

Next, you get to a level at which there is still plenty of room for dispute -- primarily involving how existing species give rise to new species. Some of these questions are merely technical in nature. Others are more philosophical. Darwin's 19th century followers were very insistent on a universe in which all evolutionary change begins with chance mutations, some of which turn out to be beneficial while others kill off their carriers. But that emphasis on blind chance -- which so many people find offputting -- is a philosophical choice, not a scientific inevitability. I can think of any number of mechanisms, from the genetic to the behavioral, by which organisms under environmental stress might increase their likelihood of giving rise to offspring which diverge from the current norm.

And from that level of the philosophical-but-answerable, you get into the philosophical-and-probably-unanswerable. Questions about whether there is something built into the nature of the universe that produces increasingly complex living systems and societies, whether there is a life force or holistic principle that drives evolution, and what role consciousness plays in the whole process.

Counting on my fingers, I see at least five levels here: fact, descriptive theory, explanatory theory, philosophical theory, and metaphysical theory. And confusing one with another will only lead to arguments and name-calling.

[JHBowden]

55. BULLSHIT

Evolution *is* a theory. Just like gravitation and electromagnetism, evolution is a theory with mountains of evidence to support it.

Calling a proposition a fact is merely asserting that the proposition is true. We believe that the theory of evolution is true, but not because we open our mouths and say it is true. Again, we believe it is true because of the evidence.

Scientists are not infallible; it is the evidence that always matters.

[BurtWorm]

58. "If I jump off the Empire State Building I will fall"

Is that a theory or a fact? Or something else?

Of course it is a prediction, but it's based on massive evidence. But isn't it also a fact that if anyone steps off the top of the Empire State Building they will fall?

Isn't it also a fact that species evolve? This is also based on massive evidence (not much of it directly observed, obviously, but some of it directly observed). Would you bet against it?

[JHBowden]

62. Truth, justification, and knowledge are not the same things.

I believe the theory of evolution is true, yes. But when justifying this belief, I cannot sit on my belief that it is true. I must provide the evidence and reasoning indicating the likelihood of the theory.

The initial poster gave the impression that evolution is a fact and is beyond debate. In science, while there are standards of rationality, nothing is beyond debate. If the truth of the theory of evolution seems like it is beyond debate, that is only because of the mountains of evidence supporting it and the crappy condition of the competing theories.

[BurtWorm]

63. Okay, I hear you.

If that's the impression the poster wanted to leave, that evolution is totally safe from challenge as a fact, then he's wrong. But there really are not many facts, if any, that are totally safe from challenge.

In the middle ages, it was a fact that the sun literally rose in the east and set in the west, revolving around the earth on a great sphere in the heavens. Now it's fact that the sun only appears to rise in the east and set in the west, because it's actually the rotating earth that revolves around the sun.

All facts are contingent.

[bpilgrim]

57. Natural Selection

Natural Selection btfly.gif (16483 bytes)

The Adaptive Strategy of an organism is not the only thing which creates biological changes. A species is always within a constant state of flux, as is the environment where they live. The obvious question is, is an organism able to adapt completely to its environment, and the honest answer is no. The environment of earth is in a constant state of flux, but changes in an environment generally occur within time spans of tens of thousands of years, save for a few examples where changes occurred in an interval of a 100 or 200 year time span (research into environmental change and evolution is on going, some researchers challenge the length of adaptive time to be more or less than the figures above).

The best example of a quick change in the environment and a species ability to adapt concerns the the color of the Gypsy Moths in England. When the industrial revolution occurred, coal and other industrial factories spewed out massive amounts of air pollutants, so much so that even during the day the skies were as dark as night. The original color of the gypsy moths was a light gray; such a color blended in with the trees in their environment, and acted as camouflage against predators. With the change in the environment the camouflage adaptation no longer functioned because the tree trunks were darker colored from the air pollution. The dark gray gypsy, once at a disadvantage and quickly eaten by predators, now survived and bred, while their lighter counterparts were eaten. As a result the gypsy moth, through adaptation and natural selection, was able to gradually change it's coloring to a dark gray-black, to match the surface of the trees covered in pollution. The gypsy moths didn't just decide one day to change their color, at the basis of such a change was the concept of Natural Selection. wpe9.jpg (7823 bytes)

Natural selection plays upon variation and adaptation, all of which occur simultaneously. There is biological variation within every species. This is best illustrated by the bell curve model of species variation. In the example of the gypsy moth, the majority of the species will have the same color trait and will be clumped into the orange and green sections of the bell curve. The lower end of the bell curve are different from the average in some way shape or form. In the case of the gypsy moth and it's adaptation for the gray color, the darker moths were at first the exception rather than the rule. When the environment began to be polluted the lighter moths which occupied the middle section of the bell curve began to be killed by predators, while the darker moths at the other end of the bell curve were not. When such a change occurs, it is said that a trait has been selected for, or a trait has been selected out of the gene pool.

source...
http://www.mnsu.edu/emuseum/biology/evolution/genetics/naturalselection.html

What still is a theory is the exact mechanism that selects what changes prosper.

the ENVIRONMENT is one of the DEMONSTRABLE mechanisms, see Darwin's Finches...
http://www.biology-online.org/2/11_natural_selection.htm

peace

[JackDragna]

60. Evolution is too a theory.

Calling it a theory, however, does not diminish its truth value. In science, a theory is designed to explain a large-scale natural phenomena. Evolutionary theory, for example, explains the diversity of life, how gene frequencies change in populations over time and many other complex interactions between organisms and their environment. Theories are the end result of numerous observations and experiments.

One can view a theory as the best model humanity has for how something in nature works. Gravitational theory, for example, is the best model we have for how space-time bends due to the presence of matter. Evolutionary theory is our model for changes in populations. If one wishes to be scientifically accurate, one should call evolution a theory. Creationists can play all the semantic games they want, but if they dismiss evolution as just a "theory," all they do is demonstrate their own ignorance.

[Raiden]

64. Right on

It's so hard to convince fundie freepers that evolution is FACT, natural selection is the theory.