Niles Eldredge Says that the
Geologic Column is Circular Reasoning?

The ever-dishonest Kent Hovind tells us in Part 4a of his Creation Seminar:

Don’t tell me they date those layers by carbon dating or potassium argon dating, or rubidium strontium, or lead 208, or lead 206, or U235 or U238; that’s not how they date them! They date the rock layers by the fossils in every case. “Paleontologists cannot operate this way. There is no way simply to look at a fossil and say how old it is unless you know the age of the rocks it comes from.” Quote goes on. “And this poses something of a problem. If we date the rocks by their fossils how can we then turn around and talk about patterns of evolutionary change through time in the fossil record.”⁴ That’s Niles Eldredge, one of the biggest evolutionists there is. American Museum of Natural History in New York. He knows it’s circular reasoning.

…

⁴Eldredge, Niles. Time Frames: The Rethinking of Darwinian Evolution and the Theory of Punctuated Equilibria (New York: Simon and Schuster, 1985), p. 52.

Hovind also provides is a 3 minute 41 second slide show version that makes the claim. The claim can also be found in this site, which is an outline of The Young Earth by John Morris, and in “Dating Rock Layers” from Genesis Park. All three cite the same Niles Eldredge book, Time Frames, and say that the quote came from page 52.

This is an example a flagrantly out-of-context quotation. The first two sentences quoted by Hovind are on page 51 and the third sentence he quotes in on page 52 and in the middle of another paragraph. Hovind quotes Eldredge, without ellipses, as if they are a continuous quote (see the box with the quote in the word transcript).

But even if Hovind had properly indicated the huge omission in the quote, it would still be out-of-context. Let us first reread what Hovind wrote immediately before this quote; the claim that he is using the Eldredge quote to support:

Don’t tell me they date those layers by carbon dating or potassium argon dating, or rubidium strontium, or lead 208, or lead 206, or U235 or U238; that’s not how they date them! They date the rock layers by the fossils in every case…

Ignoring that carbon-14 dating is not used for dating rocks, let’s point out that in the first sentence that Hovind omitted in the Eldredge quote says quite the opposite of what Hovind said. Eldredge pointed out that certain layers are dated by radiometric methods. And when also checks the paragraph before Hovind starts quoting one can get an idea of what Eldredge is talking about. Layers made up of metamorphic rocks and igneous rocks can often be dated via radiometric methods. So much for Hovind’s claim that rocks are dated by fossils in every case. Sedimentary rocks, where we generally find fossils, cannot be dated via radiometric methods. But datable strata of igneous material are sometimes found between strata of sedimentary rocks. As Eldredge tells us, “Sometimes igneous rocks, rocks we can date chemically, intrude into sedimentary rocks, and in such a fashion some hard-core ‘absolute’ dates—expressed in terms of millions of years—are available for all subdivisions of geological time.” Making a point, and then quoting someone who has refuted that point as if he supports that point is the very epitome of dishonesty.

But the quote is still dishonest ignoring all of that! Indeed Eldredge says in page 54 that was no circular reasoning. Lets look at the context in detail. Eldredge was involved in a study to see how a real species evolve through time. This required one that common, that was often well preserved, that could be easily collected, and had a long history. Furthermore he needed one that could be examined over a wide geographic range since “patterns of variation seen in modern organisms that seemed to point to significant evolutionary change through time more often than not were geographically based.” He picked a particular type of trilobite for his research.

On page 50 he tells us:

…(Rollins’ father-in-law, then a road commissioner in a small central New York town, know all of the obscure little quarries opened up on farmland for crushed stone for paving roads. Informants such as he are useful in paleontology as they are to ethnographers in more exotic climes). Through Rollins I learned such basics as knowing where you are in time when standing in a lonely cow pasture,…

What I just quoted might not seem important. But it is. The words of Eldredge are in a context of the study that he conducted. There are fossils though they be in sedimentary rock have a strata of datable volcanic ash above and below them. This allows the geologist to give the fossils a good date especially if the two datable layers are close together in time. To use a real example Meave Leakey et. al.¹ reported radiometric dates for three datable layers: 4.07±0.02, 4.12±0.02, and 4.17±0.03 million years old respectively. There were fossils between these datable layers. While one cannot date the layer with the fossils, one can say that they older than one layer and younger than another. We can say with confidence and with no circular reasoning that the fossils are a bit older than four million years old. Returning to Eldredge, his study was not one that he could do that. He was often collecting fossils in isolated quarries, road cuts, etc. and there were no layers of radiometrically datable strata to help him. He would have to find another method to date his fossils. Now we have the background to give an extended quote of what Eldredge said (what the creationists quoted is in green; bold print is mine):

Perhaps the trickiest aspect of the game of collecting over half a continent and making some sort of sense of what you find is that problem of knowing where you are in geological time whenever you stop at a stream bed, cement quarry or roadside outcrop. Paleontologists usually cannot tell time with the handy radiometrics of geochemists, who use the known rate of decay of radioactive into stable isotopes to calculate the age when a rock originally crystallized. Sedimentary rocks more than a few million years old simply do not have such isotope-bearing minerals crystallized de novo within them: unlike a granite or a high-grade metamorphic rock formed under tremendous heat and pressure, sedimentary rocks are simply accumulations of clay minerals, sand particles, small flakes of mica and the like—all formed earlier elsewhere and simple washed into the lake or seaway were they finally come to rest and pile up on the bottom. Some minerals, like the organically precipitated calcium carbonate that forms the basis for so much of the limestone (exploited by so many cement manufacturers throughout the Midwest), are formed in these sedimentary basins, but contain none of the radioactive isotopes, such as uranium and thorium, which decay so slowly to stable isotopes of lead that geochemists can measure how much of each is present and date a rock in the hundreds of millions, or even in the billions, of years.

Paleontologists cannot operate this way. There is no way simply to look at a fossil and say how old it is unless you know the age of rocks it comes from. Sometimes igneous rocks, rocks we can date chemically, intrude into sedimentary rocks, and in such a fashion some hard-core “absolute” dates—expressed in terms of millions of years—are available for all subdivisions of geologic time. The earth is 4.55 billion years old (give or take a few million; the date comes from moon samples, meteorites and graphic extrapolation from rocks dated directly earth). The oldest rocks dated on earth are about 4 billion years old. We know that the Devonian Period [that includes the time period that Eldredge studied] began about 408 million years ago and ended roughly 360 million years ago. The middle Devonian came in about 380 million years ago.

But none of that helps in a cow pasture in upstate New York. Long before radioactivity was known to physicists, paleontologists had another way to tell time. Fossils occur in the same vertical sequence thoughout the geologic column. The same, or closely similar fossils frequently occur in many far-flung localities; some are even found worldwide. This repetitive pattern of occurrence allows geological minded paleontologists to correlate: rocks are mapped, and frequently certain distinctive horizons, such as volcanic ashfalls, can be traced over great distances. But rocks in isolated quarries can be matched up according to the nature of the fossils they contain. And this poses something of a problem: if we date the rocks by their fossils, how can we then turn around and talk about patterns of evolutionary change through time in the fossil record? We need an independent time frame to know that a trilobite in Ohio is roughly the same age as one in New York before we can talk about geographic variation; otherwise, their differences might as well be ascribed to the sort of process of gradual change that Darwin thought was inevitable with the simple passage of time. The distinction between the two—gradual temporal transformation of an entire species versus geographical differentiation within a species—is crucial, and indeed underlies the very notion of punctuated equilibria.

Rocks of the Middle Devonian age crop out sporadically throughout the United States. Sometimes lying deep below the surface, covered with thousands of feet of younger rock and topsoil, where the Middle Devonian does reach the surface it is usually buried beneath a carpet of forest, farmland and concrete. In the folded Appalachians, erosion has laid the rock bare to produce some natural exposures. In the Midwest, though, it is the large open-pit quarries that provide most of the random windows into the lithified remains of these ancient sediments.

In the late 1920s, G. A. Cooper wrote his doctoral dissertation at Yale, describing in far greater detail than had ever been done the layered rocks, the statigraphy of the Middle Devonian (called the “Hamilton Group”…). Focusing on the fossils, but also minding the precise sequence of the rocks themselves, Cooper was able to correlate the sporadic exposures across New York—and later, throughout the United States. In the region around Hamilton where the rocks are 1,500 feet thick, Cooper went up each ravine, collected rock samples and fossils. he became so familiar with the Hamilton Group in this region that he was able to fit to far more restricted, isolated exposures elsewhere into his scheme of the general sequence of time in New York and down the Appalachians. When, for example, a new quarry was opened up near Sylvania, Ohio, in the 1920s, the general Hamilton nature of the brachiopods, corals and trilobites was immediately obvious to all. Grace Anne Stewart described and listed many species from a distinctive alternating sequence of gray limy shales and hard limestones. The fauna of this “Silica Shale,” as the sequence of rock was soon named, quickly became world-famous. The fossils are gorgeous, exquisitely preserved and extremely abundant. Today, more than 200 species have been found within the confines of this single quarry…

Cooper could do more than just determine the general Hamilton age of the Silica Shale fauna—which, after all, would only be saying that the Silica Shale had formed during some interval within the entire 8-million-year history of Hamilton time. He was able to do much better than that: a number of Silica Shale clams and brachiopods are known only from the lower portion of the Hamilton sequence of the East. And above the Silica lay a distinct unit, the Ten Mile Creak Dolomite, that bore a very distinctive coral fauna, identical to the corals of the Centerfield Formation, a widespread unit in New York that lies roughly halfway up the Hamilton sequence. Q.E.D.: the Silica Shale seemed to be equivalent in age to the “Skanteatles” part of the Hamilton of central New York—a much more precise correlation than merely calling the Silica “Hamilton-aged.”

Cooper’s correlation chart is a good example of a complex hypothesis. It is really a theory of time relationships among a far-flung sample of rock outcrops. Some of the particular component hypotheses of the theory have since been shown to be incorrect. Cooper didn’t get it all right, and the chart is constantly being revised in some of its details as we learn more about the rocks and the fossils of the Hamilton age. But in general, his work has stood the test of time and subsequent investigation extremely well. And it served as the basis for my work on the trilobite Phacops rana.

Cooper’s conclusions had special significance for me simply because he had not used the trilobite in which I was interested as a basis for his correlative scheme. Thus there was no danger of circularity: if Cooper had erred, and I subsequently compared two collection under the mistaken assumption they were equal in age, naturally the results, the evolutionary patterns I would report, would be less than fully correct. The pattern would depend very much on how correct Cooper had been about the relative ages of all these rocks. But at least there would be no problem of circularity. I wasn’t going to argue that the Silica Shale was the equivalent of Skaneatels because the trilobites are so similar (turns out they aren’t—part of the clue to punctuated equilibria), and then turn around and discuss the patterns of variation and evolution within these trilobites on the basis of my own time frame. No—correlations were reasonably secure, based on lots of hard work by others on different sorts of fossils….

I apologize for such a long quote, but it was necessary to establish was Eldredge was really talking about. The creationist characterization of what he said falls apart when one actually reads what he said and not a few sentences snipped and taken away from their original context.

Now let us see what kind of reasoning is used by geologists in correlation. Now discover in a hundred locations that fossil x is always strata y. It would be a reasonable to tentatively conclude that x will be found in y. And if we find x in isolated road cut that the strata has not been worked out it is not unreasonable to form a hypothesis that the strata in that road cut is strata y. It is certainly possible that that it is false, but the majority of the time it will work out. Now let’s use a bit more detailed, though admittedly still simplified example. Say the geologists discover the following fossil sequences:

Now there was no radiometric dating in the time of Darwin. So scientists had to be content with a timescale that was relative. A relative timescale tells us the order of that things happened but does not give us an actual date. Today we have radiometric dating methods than give us a direct ages. But only certain strata can be dated by radiometric clocks. Because of this the relative timescale is still more detailed than the absolute timescale that does not depend on fossils whatsoever. In the end the creation of geologic column does not depend on circular reasoning. As Eldredge stated in pages 100-101 of The Monkey Business: A Scientist Looks at Creationism:

[Early 19^th British surveyor William] Smith was surveying the terrain for one of the ambitious canal projects brought on by the Industrial Revolution. Climbing the hills, he noted that the fossils he saw always occurred in the same order. He could stand on one hill and predict what he would find on the next, based on his experience with the order of fossils. He could predict, if someone showed him suite of fossils, what fossils would be found below them, and what one could expect to find above them. He found he could take a mixed collection of fossils and tell the collector, correctly, what the sequence of fossils had been as they lay in the rocks.

There is no assumption of evolution here. It is simple observation: fossils occur in the same general sequence everywhere they are found. When pronouncing two bodies of rock strata—no matter how widely departed they may be—to be roughly equivalent in age (“correlative”) on the basis of their fossils, there is no evolutionary presupposition whatsoever. The only assumption is that identical, or near identical, fossils are the remains of organisms that lived a roughly the same time all over the earth. This is the basis, for instance, the stating that the rocks of the Cambrian, Ordovician, and Silurian age occur in the United States as well as in Great Britain where they were originally studied. We have found Cambrian trilobites, Ordovician trilobites, and other fossils in the United States—called Cambrian because they are, in some instances, dead ringers for the British fossils. Moreover, these fossils in the United States occur in the same basic sequence as the ones Sedgwick and Murchison found early in the nineteenth century in the rocks of England and Wales. So the correlation of rocks—saying two bodies of rock are about the same age—is not based on the assumption that evolution has occurred. It is based on simple empirical observation of the order in which fossils occur in strata and on standard procedures of scientific prediction and testing by further observation. And now we even have an independent means of cross-checking our assumption that similar fossils imply rough equivalence of age for the formation of two or more bodies of rock. For now we have radiometric dating as an independent check.

Now does that sound like someone who thinks it is all circular reasoning? Does that sound like someone saying that we never use radiometric dating to date rocks? If it does not than the question becomes: Why is Hovind claiming otherwise?

Also see:
“Radiometric Dating and the Geological Time Scale: Circular Reasoning or Reliable Tools?” - More detail on how it is done
More out-of-context quotations used to support creationists’ claims in this matter
A History of the development of the geologic column: Part 1 and Part 2

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