If I'm not mistaken, ID proponents generally concede that the earth is super old and that common descent is a matter of fact. I could be wrong though. (I don't really keep up with the scientific journal related to this debate enough to comment on it with any authority.)

It seems to me that the ID movement is aimed less at replacing the science of evolutionary biology, and more at breaking down the philosophy that is often labeled as "science." To be honest, I have trouble believing that a fourth grade teacher has the training, or time, to explain the science of evolution to a fourth grade student. At that level, it is mostly just metaphysical discussion, and arguably no more worthy of the biology classroom than are Einstein’s religious views.

And, despite what anyone may say, most of the science taught at that level has been R-E tarded for a very long time anyway. (It's not unusual to find elementary teachers who believe, and have for a very long time believed, that the significance of evolution is that that humans “came” from monkeys.) I hardly doubt that teaching ID as philosophy of science is going to throw a wrench into our scientific advancement when, historically, the elementary or secondary teacher at the average school has struggled to understand F-O-I-L in mathematics, or anything beyond Newtonian mechanics in physics. (Forget the ability to explain the significance of a secondary protein structure or a quaternary protein structure.)

There is a mountain of evidence suggesting that "evolution" occurred. However, having studied biology and chemistry for three years, I can say with certainty that the contemporary debates between non-scientists over ID and evolution are as scientifically illuminating as a blindfolded slap-fight between Ann Coulter and Markos "Kos" Moulitsas. You're more likely to find a scientific discussion while watching two eight year olds build an ant farm. My tendency is to dismiss almost every discussion of this topic that could appear in any newspaper, or any blog, as the political equivalent of listening to Michael Savage. (My own discussion included.) The truly good points are being made in lonely labs, and on published paper, by really boring people who wear horse-blankets for clothes and who strongly prefer Star Trek re-runs to Monday Night Football.

I am highly suspect of anyone who claims that their argument for evolution is based in science, yet could not possibly articulate the difference between monomers, polymers, proteins, nucleic acids, and ribo-nucleic acids, without resorting to Wikipedia. And even with the help of Wikipedia, I find it hard to believe that most of the people who like to puff themselves up by dissecting ID could explain the significance of those terms to evolutionary biology. In those cases, the arguments really are over whose metaphysical position is superior.

[Disclaimer: This comment is not intended as a commentary on Ronald Reagan, the Republican Party, nor any other politician, political party, any platform, or partisan view.]

A few notes...

Actually I would say that there is no agreement within the Intelligent Design community on what the age of the earth is. To quote "Pandas and People"...one of, if not the main "Textbook" of ID:

"Some take the view that the earth's history can be compressed into a framework of thousands of years, while others adhere to the standard old earth chronology"

In other words...they don't want to throw the old-earth creationists out of the loop, but they also don't want to throw the new-earth creationists out either.

Secondly, I don't think there's a reason for any 4th grade teacher to be dealing with evolution, or biology in general at all. I didn't even get started really in science classes until middle school, and my first actual biology class that delved into genetics and how evolution actually worked was in 9th grade (and I forced my way onto the advanced track then too).

I'd say that the idea that humans and apes share a common ancestor is one of the great ideas of evolution, just in that it was so radical compared to what else was out there.

And finally...I'd also say that one doesn't have to be an expert in biochemistry in order to discuss evolution. I, for example, deal with evolution in a totally different way; the fossil record. Although I have a cursory understanding of what RNA, monomers, polymers, DNA, etc. are, if you want to talk about how we come up with dates on rocks, how the fossil record changes through time, what the story of life is on earth...that I know fairly well.

I'm a common sense person. I know a little about polymers and probability. Methinks that should we receive a snippet of DNA code on our great big dish from a far distant star we would be jumping up and down with delight at having discovered intelligence "out there."

Why then, when we find that same DNA in the most simple living cell, do we insist that it must have put itself together accidentally?

Simple answer?

The truly good points are being made in lonely labs, and on published paper, by really boring people who wear horse-blankets for clothes and who strongly prefer Star Trek re-runs to Monday Night Football.

I am highly suspect of anyone who claims that their argument for evolution is based in science, yet could not possibly articulate the difference between monomers, polymers, proteins, nucleic acids, and ribo-nucleic acids, without resorting to Wikipedia. And even with the help of Wikipedia, I find it hard to believe that most of the people who like to puff themselves up by dissecting ID could explain the significance of those terms to evolutionary biology. In those cases, the arguments really are over whose metaphysical position is superior.

Excellent, excellent points Jonathan.

In most cases, both the religious believer and the religious evolutionist (non-scientists both) believe what they believe for the same reason: because their family, friends and community (plus a couple of authority figures) told them that evolution/creationism was true. And yet each side thinks that they are morally and intellectually superior to the other. It's amusing, really.

To quote "Pandas and People"...one of, if not the main "Textbook" of ID

Balta, "Of Pandas and People" was written in 1989, which is well before the beginning of the ID movement.

Yes, but like any "textbook" there have been new editions. A 3rd is in the works right now.

I completely disagree that anyone discussing evolution must understand all the complex concepts noted above. While a complete understanding of evolution might entail a thorough understanding of these complex ideas, a more general (high level) understanding of evolution does not.

I would explain Evolution as a change in the frequency of an allele (trait) in a population over time. These changes are driven by a few key factors: Mutation, Genetic Drift and Natural Selection.

Natural Selection is based on a handful of key easily understood statements:

1) Every living species faces some form of competition to survive and reproduce.

2) Within a species there is genetic difference between individuals.

3) Offspring are likely to inherit their parents genetic differences.

4) Genetic differences may assist the individual creature survive and/or reproduce.

Therefore, as Wikipedia states:

A. Natural selection is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce.
B. Evolution is a change in the traits of living organisms over generations, including the emergence of new species.

I'll skip an explanation of Genetic Drift but it also isn't difficult to grasp at a higher (non-technical) level.

I can still remember my first Evolution discussions from grade school. We studied moths living around London and how the color of the moth population changed (from light to dark)during the industrial revolution. After grasping how a population's traits can change over time, we continued on to discuss how a population within a species could potentially change to such an extent that they became in effect an entirely new species. We were discussing and understanding Evolution in grade school.

Intelligent Design, which assumes a supernatural creator, is not science because it's concepts are not repeatable, observable or falsifiable. ID has no place in the classroom except in the context of a religious course.

IOCL just barely beat me to the point I wanted to make: while the details of molecular biology certainly add to the evidence for evolution, you don't need a master's degree in biochemistry to understand the general argument, or to understand why evolution is a falsifiable hypothesis and intelligent design is not. The fossil record, for example, or the lack of optimal design of organisms due to exaptation (i.e. the panda's thumb) can be understood by any sufficiently interested layman.

IOCL's comment demonstrates that a *huge* part of the problem when discussing evolution and intelligent design is the definition of terms. If evolution is defined merely as change in the frequency of a trait in a species over time, virtually no one objects to that. This is sometimes called "microevolution," and it's what evolution proponents are actually referring to when they proclaim things such as that evolution is the foundation of modern medicine.

Likewise, ID does *not* "assume a supernatural creator." Rather the opposite. ID argues that certain biological systems show the evidence of design. Design, of course, implies some sort of designer, but that question is left open.

Likewise, a couple quibbles with Adam's post...

First, unless I'm wrong, PubMed is not an exhaustive index of all scientific literature. While (micro)evolutionary concepts may be referenced in joural articles in PubMed, I doubt that they would index journal articles on evolutionary theories. Searching PubMed for "intelligent design" seems like searching an index of astronomy journals for "behavioral psychology."

Second, intelligent design is not a religion. It is metaphysical or philsophical (as are arguments such as "if there really is a God, why does the panda's thumb look like it does"?), but it is a subject of reason, not of faith. To put it another way, there is no "First Church of Intelligent Design" anywhere.

Jonathan wrote:

If I'm not mistaken, ID proponents generally concede that the earth is super old and that common descent is a matter of fact. I could be wrong though. (I don't really keep up with the scientific journal related to this debate enough to comment on it with any authority.)

It depends entirely on who you ask, which only points up the fact that there is no ID model or theory of the natural history of life on earth. Michael Behe says he "has no reason to doubt" common descent, but he's always very careful on how he words it to give him wiggle room. William Dembski has several times implied that he rejects common descent, but hasn't really come right out and said it. Paul Nelson and Nancy Pearsey both reject common descent completely and both are young earthers. Phil Johnson doesn't say anything about it because he doesn't want to offend any young earthers who might otherwise buy his books.

The truly good points are being made in lonely labs, and on published paper, by really boring people who wear horse-blankets for clothes and who strongly prefer Star Trek re-runs to Monday Night Football.

But none of those papers have been published by ID advocates. No one has yet come up with an ID model or theory, partly for the reasons noted above - they can't even agree on the age of the earth or the issue of common descent. And no one has yet proposed an experiment by which ID could be tested. The only ID article to appear in the scientific literature was Meyer's article in the Proceedings of the Biological Society of Washington, and that was just a review article with no research done at all, and no suggestion of how such research could be done or what the ID theory actually says (other than "evolution is wrong", which is hardly a theory). That was really Adam's point, I think. There are thousands of scientists in various fields doing research that flows from evolutionary theory, testing various aspects of hypotheses of lineage and descent, using knockout experiments to trace evolutionary pathways, sequencing molecular homologies, testing the function of developmental genes, and so forth. There is simply none of that being done by ID advocates. They spend a great deal of their time, energy and money on PR and political campaigns (they just hired a major PR firm) and none of it on actual research.

Listless lawyer wrote:

Balta, "Of Pandas and People" was written in 1989, which is well before the beginning of the ID movement.

Actually, this book is billed by the publishers and accepted by ID advocates as the first ID textbook. In fact, the phrase "intelligent design" was coined in that book. But interestingly, comparison of the early versions of the book to later versions shows that all they did was take the word "creationism" or "creation science" and replace them with "intelligent design", which is quite telling (documentation here.

Ed, I don't think the ID people are trying as much to replace evolution with religion as they are to replace it with truth. Years ago I read both The Origin of Species and The Descent of Man cover to cover--and swallowed it hook, line, and sinker. So detailed! So overarching! So beautiful and all-explainin! Years later, critical thought set in. The theory was full of leaps, of things that "must have" occurred but no amount of imagination could posit a step-by-step scenario as to a possible "how." Microevolution is incontrovertible. Macroevolution is dead in the water, with DNA providing the coup de grace. Now I can't even get over the first hump in the theory of evolution--the formation of the first living cell.
You want science? How about the mathematical science of probability which shows the impossibility (not the improbability, but the impossibility) of that first cell's DNA coming about through chance encounters among chemicals.
And the steps don't get any more likely as you go up the ladder from amoeba to man.

Dorothy Vining wrote:

Microevolution is incontrovertible. Macroevolution is dead in the water, with DNA providing the coup de grace.

A bare assertion without a stitch of evidence or explanation to support it, or even any definition of the terms used. What is the difference between "microevolution" and "macroevolution"? At what level is the barrier that prevents the first from turning into the second, and how does that barrier operate? And why on earth is DNA the "coup de grace" in regard to those first two questions?

Now I can't even get over the first hump in the theory of evolution--the formation of the first living cell.

The first living cell is not "the first hump" in the theory of evolution. The first replicating life forms were probably pre-cellular.

You want science? How about the mathematical science of probability which shows the impossibility (not the improbability, but the impossibility) of that first cell's DNA coming about through chance encounters among chemicals.

This is just so much empty rhetoric. There is no "mathematical science of probability", that's a nonsense phrase. There is the field of probability and statistics within mathematics, of course, but it is impossible to construct a probability equation for the odds of "that first cell's DNA" forming through "chance encounters among chemicals". Nor is either premise of this statement an accurate reflection of abiogenesis theory, which generally holds that DNA developed after the first self-replicating life forms. And bear in mind that chemical reactions are not random. Some chemicals react or bond with other chemicals and some do not, so the interaction of chemicals is not at all random. That is just one of the many variables that we cannot know that makes it impossible to construct a valid probability equation for abiogenesis. And if you think you can build one, feel free to offer it here. I'll give you a hint: probability equations between with "P=".

So, um. Dorothy wasn't joking on that other thread about being completely clueless about the actual science of evolution. Not only clueless, apparently, but very, very lazy, since she apparently can't be bothered to type "evolution sexual reproduction" into the google search field and, like, actually read some of the various accounts on offer. (She also apparently has never been informed of the basic fact about the science that it has progressed a thousandfold since Darwin's own publications!?!)

Taking note of philosopher's brilliant suggestion I Googled "evolution sexual reproduction" and found the following quote which says exactly what I am trying to say and you are refusing to hear:

"Further, not a one of you answered my question. How would sexual reproduction evolve from asexual reproduction? Even if the advantages you stated are true (and I think they are), that does not explain how those species came to be sexually reproducing in the first place. I simply cannot fathom how that leap could occur."

I'll bet you can't even IMAGINE a step-by-step scenario for such a transformation. You will continue to hold it "must have" just happened.

Honeybabe, put a little more "meat" into your responses and be a little less condescending. Also try answering the question instead of running in circles around it.

Dorothy Vining wrote:

Also try answering the question instead of running in circles around it.

That's rather ironic given that you skipped over my entire response to your comment and ignored it completely, not bothering to answer any of the questions or dispute any of the claims contained therein.

Dear Ed - I responded to philosopher's post, not yours. (Unless Ed Brayton and philosopher are one and the same.) I'm sure you know the difference between micro- and macro-evolution and I wouldn't want to talk down to you. As for the self-replicating RNA, you are just moving the hump down a step, positing that it probably or likely or may have happened. RNA is still a complex "language" which many reasonable people doubt could come about accidentally. I'm sure you'll let me know if and when someone comes up with self-replicating RNA. Then we'll have to figure out how it acquires more genetic material, again, and here's the stickler--BY CHANCE!

And I'd still like some ideas as to how any asexual animal morphed into a male and female capable of mating, all in one fell swoop. That's a real mind-boggler.

Dorothy Vining wrote:

I responded to philosopher's post, not yours.

I realize that, and that was my point. You accused him of not answering questions but instead running circles around them, yet you had entirely ignored the questions I asked you and the responses I had written. Hence, the "how ironic" statement on my part.

I'm sure you know the difference between micro- and macro-evolution and I wouldn't want to talk down to you.

Well, the problem is that I've heard about 50 different definitions of the difference between "microevolution" and "macroevolution" and your claim that the first is "incontrovertible" while the second is "dead in the water" has not been given any definition at all. And "I'm sure you know the difference" is not an answer to that question (hence, more irony of the type mentioned above). What exactly is the distinction between micro and macro evolution and where is the barrier? At the species level? Genus? Family? And wherever this barrier allegedly is, how does it operate?

As for the self-replicating RNA, you are just moving the hump down a step, positing that it probably or likely or may have happened. RNA is still a complex "language" which many reasonable people doubt could come about accidentally. I'm sure you'll let me know if and when someone comes up with self-replicating RNA. Then we'll have to figure out how it acquires more genetic material, again, and here's the stickler--BY CHANCE!

Even if this statement of how abiogenesis hypotheses operate was an accurate one - and it's not - it does nothing to support the argument that I challenged. With yet more irony, it's just dancing around the question. Let me refresh your memory. You claimed that the "mathematical science of probability" (whatever that might be) proves that it is "impossible" for "the first cell's DNA" to come into existence through "chance encounters among chemicals". There are two major problems with that claim, both of which I've already stated and both of which you ignored. First, chemical reactions are not random, as you claim. Some chemicals react or bond with other chemicals and some do not. That clearly sets constraints upon those chemical reactions, favoring some and disfavoring others. Hence, it's not a purely random system as you allege.

Second, it's simply impossible to build a valid probability equation to support your argument. You don't know and can't approximate all of the variables and you can't compensate for the non-random aspects of the situation. Using a similar assumption of total randomness, one can easily prove that it is "impossible" for you to exist, yet you do.

Dearie me. I've been hoping someone else would weigh in and tell you to stop caviling about the meanings of "random," and "micro- and macroevolution" in order to avoid the nitty-gritty questions. Just look them up in Google and get on with it.

Regarding the probability thing, here is an excerpt from Stephen Meyer's fine study. He is far more learned on the subject than I (or you, for that matter). (And he's talking about something far simpler than DNA).

"If one also factors in the probability of attaining proper bonding and optical isomers, the probability of constructing a rather short, functional protein at random becomes so small (1 chance in 10^125) as to approach the point at which appeals to chance become absurd even given the "probabilistic resources" of our multi-billion-year-old universe." http://www.arn.org/docs/meyer/sm_dnaotherdesigns.htm

Before you discontinue this thread may I have my final say? I know now that you will not tackle the questions of how the first living cell came to be or how male and female differentiation occurred in the course of evolution. As Arthur Keith, anthropologist and atheist said, "Evolution is unproved and unprovable. We believe it only because the only alternative is special creation, and that is unthinkable."

To get back to the original cause of this discussion, Bush's statement that the idea of intelligent design might be mentioned in school seems to me quite reasonable. Evolution (the "particles to people" kind) is definitely a theory and in the interest of truth it might well be communicated that many folks of respectable intellect know it is unprovable and think it is unlikely.

In a Gallup poll on the subject (2004), 45 percent of Americans believed that God created human beings in their present form 10,000 years ago, while another 38 percent believed that God directed the process of evolution. Only 13 percent accepted the prevailing scientific view of evolution as an unguided, random process.

Evolution should not be taught as established scientific fact and students might even be encouraged to bring some critical thinking to the subject. How could that hurt?

Thanks for a fun ride. I have learned something on the journey. May we all seek and find truth.

Dorothy Vining wrote:

Dearie me. I've been hoping someone else would weigh in and tell you to stop caviling about the meanings of "random," and "micro- and macroevolution" in order to avoid the nitty-gritty questions. Just look them up in Google and get on with it.

In other words, you can't be bothered to define your own terms. I don't think there is any distinction between micro and macro evolution. You claim there is one, but you refuse to define the distinction between them. I would suggest it's because you're just mindlessly parroting buzzwords you don't really understand.

Regarding the probability thing, here is an excerpt from Stephen Meyer's fine study. He is far more learned on the subject than I (or you, for that matter). (And he's talking about something far simpler than DNA).

A study? What on earth makes you think Meyer's article is a study? There is no research performed in it. What you are citing is an op-ed piece in a religious magazine, not a study in a scientific journal. Meyer is not a scientist, in fact, but a philosopher and the man has never done any scientific research whatsoever. You can declare him "more learned" all you want, but that is little more than an unsupported assertion. He has no expertise or experience in the kind of research he is claiming can't be done. If all you have here is a naked appeal to authority, all one would have to do is cite any of the dozens of actual scientists doing abiogenesis research who dispute his claim. But of course, appeals to authority don't matter. What matters is whether the claim can be defended rationally. So let's look at his claim:

"If one also factors in the probability of attaining proper bonding and optical isomers, the probability of constructing a rather short, functional protein at random becomes so small (1 chance in 10^125) as to approach the point at which appeals to chance become absurd even given the "probabilistic resources" of our multi-billion-year-old universe."

Meyer is constructing here what we on my side like to call the Argument from Really Big Numbers. But such a probability equation is only valid if: A) you actually can quantify and control all of the variables other than probability (you can only solve for one unknown, not two), and B) the process is truly random. Neither of those things are true about Meyer's argument. Using this same sort of reasoning, as I said, one could easily prove that it is virtually impossible for any event to take place. For instance, my friend Marshall Berman, a physicist, offers this example:

Go outside and pick up a small rock. The probability of that rock being on that spot on the earth *by chance alone* is roughly the area of the stone divided by the surface area of the earth, or about one chance in 10 to the 18th power (one followed by 18 zeros). If picking up the stone took one second, the probability of such an event occurring at this precise moment over the lifetime of the universe is now even smaller by another factor 10 to the 18th power! This simple event is so incredibly unlikely (essentially zero probability) that one wonders how it could be accomplished!

For an examination of the validity of probability equations like Meyer's, see this essay from another friend of mine, Ian Musgrave. Unlike Meyer, Ian is an actual scientist, a biochemist, who has done research (that means actual studies, not imagined ones) on the formation of proteins.

As Arthur Keith, anthropologist and atheist said, "Evolution is unproved and unprovable. We believe it only because the only alternative is special creation, and that is unthinkable."

Another quote that is passed around from creationist to creationist, but no one ever provides an actual citation for it. It has never been found anywhere in the writings of Arthur Keith. It's almost certainly a bastardized version of the highly distorted quote from D.M.S. Watson from 1929. At any rate, Arthur Keith died half a century ago. Even if he had said such a stupid thing, he doesn't speak for anyone but himself and he is wrong.

To get back to the original cause of this discussion, Bush's statement that the idea of intelligent design might be mentioned in school seems to me quite reasonable.

He didn't say it should be "mentioned". He said both should be taught in the same manner.

Evolution (the "particles to people" kind) is definitely a theory and in the interest of truth it might well be communicated that many folks of respectable intellect know it is unprovable and think it is unlikely.

Of course evolution is a theory. This is relevant only to those who misunderstand what that word means. "Theory" is not a step on a ladder of certainty below "unproven", it's the highest level of certainty attained in science. Other theories include the germ theory of disease (upon which all of modern medicine is based), the kinetic theory of gasses and the theory of relativity. The fact that those are theories does not mean they are in some great doubt and the same is true of evolution.

Anonymous, the problem is that if we received "a snippet of DNA" over the radio waves from distant stars, we would not know that we had received it. DNA itself is dense and cryptic and mostly resembles, to the human viewing, noise. It does not resemble "information" as we understand it in the technical sense.

The first problem I have with ID is that it fails to understand that the recognition of information, according to information theory, requires two plain old human beings to make sense of the information: a sender, and a receiver. When we use computers to do this, they are programmed by human beings, and "the sender" and "the reciever" in these cases are algorithmic systems iterating things well-understood by human beings. The systems, therefore, require that "information" be recognized by analogy, and the same is true of the original ID example, Paley's watch found on a forest floor: we know that signal X, or Paley's watch, are designed because signal X and a watch resemble things human beings make, not natural processes.

DNA and the outlay of the human body look like they come from evolutionary processes, simple, iterative systems obeying the basic, regular principles of chemistry and physics. There is nothing in the body that is "irreducibly complex," as Michael Behe would wish it, and many parts of the body that IDists love to harp about such as the eye, the inner ear, the reproductive tract, and so on, are a mess for surgeons and IDists precisely because they emerged from previous evolutionary steps that adapted them to new purposes for which they were "good enough."

The other problem I have with ID is that it is heretical. It's an insult to your fellow man because it presupposes that you must deceive him in order for him to be receptive to the gospel; it is an insult to the gospel because it supposes that the gospel is not good enough on its own, and we need more, we need "evidence," however manufactured from thin air, to be valuable; and it is an insult to God because it reduces Him to some basement tinkerer who can't get the physics right the first time he said, "Let there be light," and so has to come down an putter with his creation until it's no longer half baked.

As one wag put it, when the Lord asked Job if he knows how the Earth was made, an IDist would raise his hand and shout, "I do!"

And finally, one of the best cast-offs of science is technology. The principles of evolution are used in laboratories around the world, from vitners selecting advanced yeasts to computer science facilities "evolving" from first principles better and faster search and selection algorithms for new medicines. If ID had merit, you can bet that big pharma would be investing heavily in ID-based research programs. They are not, because ID has nothing to contribute to our understanding

To quote one of your own, evolutionsts have deluded themselves into thinking that they are scoring points against opponents who are simply playing a different game.

The difference is not in the science. It's in the context within which you interpret the science. Whether its proponents like to admitit or not, evolution rests on presuppositions and conclusions that are fundamentally flawed.

Teaching either intelligent design or evolution as the backstory for science is poor policy because, even though intelligent design at least recognizes that the presence of order and design implies the existence of an orderer or a designer, neither side can establish that its thesis is correct. [And, no, this isn't simply an example of "Brayton's relativism" (identified as such to avoid confusion with real relativism).]

As a result, scientific, intellectual and philosophical honesty and integrity demand that you present not only the facts and results that support your thesis but also those that differ from your thesis so that the exploration of the world we live in and the search for meaning don't get muddied by erroneous presuppositions. In other words, if you're going to teach anything, you have to teach both.

Just in case somebody missed it, I am a creationist - I think it presents the best, most logical, most internally consistent, and most coherent explanation for the existence of life. I think we're going to be somewhat surprised at how old the earth really is, on both sides, although I do not believe the data is consistent with an age of "billions and billions" of years old.

For example, so many people have accepted the basic conclusion that the earth is 4.3 billion years old, even though scientists agree that they have not found a way to determine the exact age of the Earth directly from Earth rocks because the Earth's oldest rocks have been recycled and destroyed by the process of plate tectonics. (from the U.S. Geologic Service)

Further, the basis for the calculation is old, presumed single-stage leads coupled with the Pb ratios in troilite from iron meteorites, specifically the Canyon Diablo meteorite. In addition, mineral grains (zircon) with U-Pb ages of 4.4 Ga have recently been reported from sedimentary rocks in west-central Australia. (also from the U.S. Geologic Service)

However, all of those assumptions are based on theories postulated between the years of 1785 and 1800 by James Hutton and William Smith. As far as I am aware, no one has gone back to those theories and assumptions with the new technology available to determine whether those assumptions are, in fact, valid.

Until such time as the initial theories on which evolution is based are reviewed and tested and reexamined (as evolutionists demand be done with every scrap of data produced by "intelligent design theorists"), the assumptions should not be taught as fact.