On the Age of the Earth: more than just meteorites!

If you inquire of your favorite search engine as to the 'age of the Earth', one number should dominate your results: 4.54 billion years. During the recent debate, Ken Ham was quick to point out, however, that this age is obtained through analysis of meteorites, and not the Earth itself. To conclude that the Earth is 4.54 billion years, therefore, we must argue that the principal, planetary components of our solar system formed at approximately the same time. In other words, this age depends on the fundamental accuracy of nebular theories in depicting our planet's earliest history.

A recent commenter on this blog also raised this point, so I'll reiterate my response:

"[Ken Ham] was correct that the accepted age of the Earth (~4.5 billion years) derives mainly from dating of meteorites. There's nothing wrong with this, so long as the meteorites are indeed the same age as the earth and derived from the same material from which our solar system form...

Although no rock on Earth is dated exactly at 4.5 billion years (why would we ever expect that?), we do have samples of zircon minerals that date to 4.2–4.4 billion years old... The fact that Earth materials approach 4.5 billion years, but never actually reach it, confirms the meteorite-based age of 4.5 billion years for the solar system and for the Earth itself."

Yesterday's issue of Nature Geoscience featured the latest research (Valley et al., 2014) on the very zircons I cited (see the BBC's report here). These tiny minerals had previously been dated through a very precise, U-Pb concordia method. Given their long and likely unpleasant history (it was a hot young Earth!), however, researchers sought to confirm the validity of the age through the latest in hi-tech microanalysis. Questions remained as to whether factors like radiation damage or trace-element diffusion had compromised the models used to calculate the zircons' ages. Radiation damage would have occurred during the radioactive decay of Uranium, when high-energy particles damaged the crystal structure on their way out. Also, little is known about the mobility of lead (Pb), the radiogenic daughter product of this decay chain, within the crystal itself. If the diffusion of lead were higher than expected, then the assumption of a closed system is no longer valid, and the calculated ages of 4.2–4.4 billion years would represent slight overestimates.

Using a combination of instruments—Scanning Electron Microscope (SEM), Electron Backscatter Diffraction (EBSD), Secondary Ion Mass Spectrometer (SIMS), and a Local Electrode Atom Probe (LEAP)—the research team constrained the distribution of trace elements, the integrity of the mineral structure, and the measured isotopic ratios to confirm that the previously calculated ages were indeed valid. These results are consistent with a 4.54-billion-year-old Earth and solar system, an early magma ocean, and the presence of solid crustal rocks shortly after Earth's formation.

So the next time anyone takes Ham's lead in raising doubts about the currently accepted age of the Earth by directing you to meteorite analyses, be sure to inform them that the oldest Earth materials date so close, that the difference is inconsequential. One added lesson to this tale is that while geochronology demands that assumptions are made, these assumptions can be—and frequently are—tested thoroughly through independent techniques. Simply pointing out that assumptions exist in the historical sciences is not an argument against their conclusions. But since Ken Ham's paradigm lacks the predictive capabilities and scientific rigor of conventional geology, these red herrings are perhaps the best he can offer.

"45 thousand-year-old fossil wood encased in 45 million-year-old basalt": Conflict Revisited

One point lost by Bill Nye in the recent debate with Ken Ham was the repeated assertion that YEC researchers had dated fossil wood ~1,000 times younger than the basalt in which it was encased. If the assertion holds, then radiometric dating methods to which Bill Nye appeals as evidence for an old Earth are potentially flawed. Unfortunately, Bill Nye did not seem familiar with the claim, reported originally in 1993, despite my prophetic counsel. ;)

Where did these samples come from, and why were they sent to labs for radiometric dating?

In 1993, several samples of charred and petrified wood were collected during construction of a mining ventilation shaft in central Queensland. The wood samples were seemingly well preserved inside the lava flow that encased them. Since the layers of basalt overlay early Cenozoic sediments, the expected age of the lava flow might be a few tens of millions of years. Not convinced by conventional ages of this geologic column, however, local 'young-Earth' geologists paid to have the basalt dated by the K-Ar method and the wood fragments dated by the radiocarbon method. Their reasoning was simple and seemingly innocent: if indeed the Earth is old, then fossilized wood from an ancient lava flow should contain no radioactive carbon (14C) today and will not yield a finite age; if the Earth is young as we claim, however, then detectable 14C should be present in the fossilized wood and the K-Ar age of the basalt cannot be taken seriously.

A full report of this study by Dr. Andrew Snelling of Answers in Genesis is available for download from the Institute for Creation Research [Snelling, 2000. Creation Ex Nihilo Technical Journal, Vol. 14, No. 2, p. 99-122]. The 24-page publication is rather verbose, reading more like a drawn-out lab report than a scientific study, but it contains all the details necessary to assess the feasibility of Dr. Snelling's extraordinary claims.

Wait, if the fossil wood and basalt are both older than 6,000 years, doesn't Ken Ham undermine his own position by citing this study?

I've described at length how apologists at Answers in Genesis use the radiocarbon and Potassium-Argon (K-Ar) methods to argue for a young Earth. In short, they criticize the assumptions behind each dating method. For example, 'model' K-Ar ages assume that all argon was expelled from the sample before molten rock cooled, starting the radiometric clock. If any argon was trapped in the mineral structure, however, then the rock will appear far older than it actually is. We have known for half a century that excess argon may be trapped in lava flows (especially underwater flows under high pressure), so much research in geochronology is devoted to improving the models. Today, more sensitive instrumentation and the aid of computer models allow geochronologists to identify 'excess' argon and calculate ages with far more precision than even a decade ago.

Given the demonstrated robustness of the K-Ar and Ar-Ar methods with these improvements, YEC's have more recently attacked the assumption that radioactive decay occurred at a constant and known rate throughout history. Many of them suggest that during/after the Flood, radioactive decay rates increased substantially, giving the false impression that most rocks are millions or billions of years old. Despite their attempts to confirm this through scientific investigation, however, the claim remains ad hoc and unsubstantiated. On the other hand, continued success using the K-Ar system in pinning down geological events, as well as confirmation from independent dating methods, gives us ample reason to believe that the model assumptions are valid and verified.

The radiocarbon method is far more complicated than is commonly presented, so YEC's have been successful in twisting its results to support their own paradigm. Traditionally, radiocarbon dating assumes that the relative concentration of 14C (the rare radioactive isotope, compared to the stable forms 12C and 13C) does not change with time. When this assumption is used, the results are reported as "radiocarbon years before present". It is important to distinguish between "radiocarbon years" and "calendar years", because we know that the relative concentration of 14C does indeed change over time. The production rate of radioactive carbon in the atmosphere depends on the magnetic field strength, for example, of the Earth and our sun. The YEC can argue, therefore, that prior to the flood, the relative abundance of 14C was much lower than today. If this assertion holds, then plant and animal remains from before the flood should yield dates many times older than their 'actual' age (4,500–6,000 years).

To document the relative abundance of atmospheric 14C over time, geologists use records that can be dated independently of the radiocarbon method. For example, tree-rings and varved lake sediments preserve annual cycles, which may be counted to obtain the actual age of each layer. When tree-rings and varved sediments are dated by the radiocarbon method, the 'radiocarbon age' of each annual band is compared to the real age to construct a calibration curve. This curve removes the assumption in conventional radiocarbon dating that 14C was constant over time.

Stalagmites provide another tool for gaging the history of atmospheric 14C, since these banded records are datable by the U-Th disequilibrium method or, in ideal cases, counting annual bands. By radiocarbon dating calcite along the growth axis of the stalagmite and comparing these ages to U-Th dates, geologists can test and refine the calibration curve (e.g. Vogel and Kronfeld, 1997). These highly corroborated, independent lines of evidence thoroughly disprove the YEC claim that atmospheric 14C increases significantly only after a recent, global flood.

In summary, yes: Ken Ham undermines his own position by citing this study, though he does not mean to.

Why did the fossilized wood give an age of 45,000 years, and how is this possible if the lava flow solidified millions of years ago?

Dr. Snelling submitted two samples of wood to two independent laboratories for radiocarbon dating by Accelerator Mass Spectrometry (AMS). He argues that since the lab obtained 'finite ages' from organic-derived carbon, the fossilized wood cannot possible be tens of millions of years old. He reports the results as follows:

   Sample                             Lab              Age (Radiocarbon Years Before 1950)
"Wood in drill core"             Geochron          >35,620 ± ?
                                         ANSTO               44,700 ± 950
"Other wood"                    Geochron           29,544 ± 759
                                         ANSTO               37,800 ± 3,450

You should notice three features immediately from this table that warrant suspicion of Dr. Snelling's interpretation:

First, all of these ages are close to the practical limit of radiocarbon dating. Even today, radiocarbon ages exceeding ~40,000–50,000 years are commonly considered suspect, because so little radioactive carbon (14C) is being measured that it becomes nearly impossible to distinguish it from contamination or background interference (more on this later). In 1993, this caution was even more applicable, which is why many important geological studies have been updated in recent years from fresh samples analyzed with better equipment.

Second, neither set of dates overlaps within uncertainty, as the sample age differs substantially from one lab to the other. Ages for the "other wood" samples differ by more than 8,000 years, meaning that Geochron measured more than twice the concentration of 14C in the same sample, compared to ANSTO's analysis. If the 14C in these wood samples were derived from a pre-Flood atmosphere, as Ken Ham and Dr. Snelling claim, then all samples should yield the same age. At the very least, each laboratory should be reporting the same concentration of 14C in the duplicate samples. But they don't. From this fact alone, we should be very suspicious that the measured 14C derived from the wood itself. More likely, we might conclude that the 14C concentration differed because variable amounts of atmospheric contamination were incorporated during each lab's preparation methods. These radiocarbon dates do not reflect the age of the fossilized wood, therefore, and do not substantiate Dr. Snelling's claims.

Third, two of the analyses (first and last samples) yielded large uncertainties, which can result when too little 14C is present, or when the source of 14C is not consistent. In the latter case, the source of 14C might be a mixture of contamination sources: atmospheric CO2 or organic acids still bonded to the fossil wood, residual atmosphere inside the sample chamber, or the tiniest of leaks in the vacuum lines. As one who deals daily with mass spectrometers, I would suggest that all three are likely candidates.

Why?

Mass spectrometers do not count atoms of 14C directly, but compare electric intensities produced by ionized particles hitting Faraday cups at the end of a vacuum tube. In theory, particles of the same mass should all follow the same path along the magnetically charged vacuum tube, so the Faraday cups can be positioned to catch each isotope. In reality, particles of the same mass do not hit the same spot consistently, but produce more of a Gaussian distribution. Imagine a fire hose spraying onto a wall: most of the water hits in the center of the stream, but some veers off to the side. If the mass spectrometer measures only 14C (and not 13C bonded to hydrogen, for example), which is distributed evenly through the sample, then the center of the peak is easily found by the instrument. Wider peaks result from low or inconsistent signals, and help us understand why such large uncertainties were associated with two of Dr. Snelling's samples.

Dr. Snelling provides several additional clues that would lead any other investigator to find better samples for dating. First, the basalt flow encasing the wood was only ~21–25 meters below the surface, meaning that it was long exposed to surface waters percolating downward into the rock. These surfaces waters contain not only modern atmosphere, but organic acids that bond tightly to the wood. The wood fragments themselves show evidence of being altered by intruding waters, as Dr. Snelling notes (p. 8): "Permineralization was too advanced" to identify taxonomically important features under the electron microscope. The porous and jointed (fractured) basalt was also altered (p. 14):

"The basalt in the drill core does, in fact, come from the zone of weathering...where percolating oxidizing ground water readily alters minerals and rock chemistry by dissolving and removing various elements."

Yet this basalt was shipped to a lab for K-Ar dating, after which Dr. Snelling criticized the inconsistent and apparently old results. But that is another issue...

The fact that Dr. Snelling's wood samples were long exposed to modern atmospheric and plant material means that at least some of the measured 14C derives from contamination. Despite Dr. Snelling's rant that the laboratories made thorough efforts to remove contaminants and "staunchly defended [the ages] as valid", he admits himself that it is impossible to exclude all contamination. Acid washes cannot contact every single surface of the sample, perfect vacuums are not obtainable in nature, and electrical interference is a constant reality. He may continue to suggest that contamination could not have been large enough to explain finite ages of 30–40,000 years, but he cannot prove this. On the other hand, we can disprove his claim through his failure to replicate the results of his analyses from independent labs.

Dr. Snelling's article mentions that "a δ13C (V-PDB) value of −25.69‰ [is] consistent with terrestrial plant organic carbon...ruling out contamination." Is he right?

Of all the claims made by Dr. Snelling's article, this one is the most obviously and demonstrably false. Forgive my roundabout answer, but this point is important.

In AMS radiocarbon analyses, the relative abundance of 13C (reported as a δ13C value) is routinely measured, because model radiocarbon ages assume that the δ13C value is exactly -25‰. This value represents a reasonable average for the isotopic composition of plant material utilizing C3 photosynthesis, like an oak tree. However, if you were to radiocarbon date a piece of ancient corn (a C4 plant, whose average δ13C value is much higher, around -13‰), you would have to consider that the corn begins with slightly more radioactive carbon (14C) than something like an oak tree of the same age. The difference results from the fact that during photosynthesis, plants preferentially incorporate the lighter isotope(s) of carbon, but the preference is stronger among C3 plants than C4 plants. Since 14C is much heavier than 13C or 12C, it is not incorporated at the same rate as the other isotopes, and this rate varies among photosynthesizers.

If you mix carbon sources with differing isotopic compositions, the δ13C changes proportionately. For example, let's mix 5 grams of wood with a δ13C value of -25‰ and 5 grams of calcite with a δ13C value of 0‰. The resulting δ13C of the mixture is -12.5‰, or a weighted average of the two sources. So what if the 14C in Dr. Snelling's fossil wood samples derived entirely from contamination? Wouldn't the contaminant shift the δ13C value, as he claims?

No. The concentration of 14C in the modern atmosphere is ~10^-12%, or less than one part per trillion. To contaminate a 14C-free sample with enough modern organic carbon to yield a radiocarbon age of ~45,000 years, less than 0.4% of the sample's mass needs to be derived from modern material. If that material is bacteria (δ13C = -27‰ to -33‰) or humic acid (δ13C = -27‰), the δ13C value of the sample will not shift noticeably, because it is so close to the composition of the fossilized wood. But even if the material were atmosphere (δ13C = -7‰) or mineral carbon (δ13C = 0‰, give or take), the δ13C value of the sample would not shift to an extent detectable by the mass spectrometer. Here is the math:

(0.996 * -25.0‰) + (0.004 * 0.0‰) = -24.9‰

Keeping in mind that the uncertainty is close to 0.1‰, and the actual δ13C of trees ranges by 5–6‰...

Conclusion

Ken Ham's appeal to young fossil wood within old basalt may have caught Bill Nye off guard, but his claim remains unsubstantiated. The actual radiocarbon ages of this fossil wood were not reproducible by independent labs within analytical uncertainty, suggesting that contamination and/or background interference was responsible for much of the detected radiocarbon. Recent advances in AMS radiocarbon dating have focused on how to account for the fact that contamination is always introduced during sample preparation and how to correct for various kinds of background interference. Regardless, radiocarbon ages close to the practical limit of the method are always treated with some suspicion.

Radiocarbon dating of independently datable materials (lakes, tree rings, and stalagmites) provide highly corroborated calibration curves of radiocarbon activity over the past ~50,000 years. These studies alone disprove the notion that a recent, global Flood severely impacted concentrations of atmospheric 14C. Combining these records with the inherent uncertainties of the radiocarbon method, which were less resolved in 1993, we might conclude that Ken Ham's proposed dating conflicts are misleading at best.

Ham and Nye agree: Ken Ham's creation model is not scientifically viable

Ken Ham deserves credit. As many predicted, he was better prepared to defend what he believes in a moderated public debate. That is not to say that he was successful, but only to clarify a point so frequently overlooked: creationists are generally neither stupid nor ignorant, and there is a reason that so many find Ken Ham convincing. But debate performance aside, let's recall the thesis of the debate:

"Is creation a viable model of origins in today’s modern, scientific era?"

Bill Nye's response is rather obvious. While Ken Ham initiated the debate to defend this thesis in the positive, however, in one sentence during the Q&A session, he managed to expose a subtle truth of his own position: the creation model to which he holds is not scientifically viable.

I will return to this point later, but first I wanted to review a number of comments made during the debate. No doubt, you'll find a hundred articles like mine today, so I'll try to keep these unique to my experience/specialty:

Who won the debate?

I would say that in asking this question, we are missing the point of public debate. Declaring a winner for any debate depends on a number of criteria (how well the debaters supported/disproved the thesis, the effectiveness of their rebuttals, how well they stayed on topic and within the rules of the debate, etc.). These points are relevant to members of a debate team, who are training to be lawyers, politicians, or businessmen, where they will be expected to be persuasive in a timed setting. In our case, however, it serves little purpose, for it gets us no closer to the real question: who sided with truth? Public debates are rarely effective tools for determining truth. Nonetheless, too many audience members expect that a debate is not fruitful unless one side capitulates in public recantation.

So what good is a moderated public debate? It informs the audience of the arguments supporting two sides of an issue, as well as the rebuttals considered valid by representatives from each side. If you failed to come away from this debate with a better understanding of what each side believes and why, then the winner of the debate is, well...not you.

Debate? What debate?

In my opinion, unless cross-examination comprises a significant portion of the event, it should not be called a debate. In cross-examination, one debater is allowed to pose only a line of questioning to the other (i.e. he/she cannot make statements or arguments, only ask questions; the opponent cannot respond only to those questions). This allows each side to focus on a specific point and force the opponent to defend it at every level. Without cross-examination, so many statements go unchecked that the audience is left only to trust one side or the other.

What we observed rather was an alternating set of presentations. Although informative, we should not be surprised that the topic of the debate was scarcely addressed. Furthermore, allotting only 5 minutes of rebuttal to a 30-minute statement is both unfair and unwise.

On this point, we should take note that not once did Ken Ham answer or try to support the thesis of the debate. He argued that creationists could be effective scientists and develop technology, that secularists have hijacked terms like science and evolution, that dating methods are in conflict, that he obtains his reconstruction of history from the Bible, and that naturalism presumes theism to conduct science and also leads to moral decay. All of the time spent arguing these points serves well for advertising, but does not help us to answer the question in debate.

Creation confirmed by observational science?

Several close exceptions were Ham's attempts to say that his creation model is confirmed by 'observational science', for example in that there is only one human race or that speciation can occur within 'kinds'. But he did not explain how and why his model predicts modern data. "Race" is not a rigid biological term, and as far as we can tell, the human 'races' descended from a large population in Africa—not a single family in Armenia/Turkey. The Hebrew phrase translated "after their kind", moreover, is better rendered "of all kinds", implying that God brought forth diversity from monotony and singularity. It does not necessarily support his idea of a phyletic "orchard"; if anything, it sounds like evolution!

So how do we test between Ken Ham's model and competing ones, like evolution? Ham cannot offer a method, because his model is not scientific; it involves only retrospective fitting of a model to known data, so it can accommodate any dataset. For example, the same genetic methods used to conclude that dogs derive from one ancient population of wolves also suggests that dogs share a common ancestor with all other mammals. To exclude this genetic evidence and cut off the evolutionary tree arbitrarily, calling it an 'orchard' instead, is both inconsistent and dishonest. Ken Ham undermines his own position in raising these points.

Defining science

As I've argued many times on this blog, Ken Ham's sharp epistemological distinction between observational and historical science is invalid. Historical science is derived from the experimental, in that rather than design an experiment to collect data, we collect data in nature to test and reconstruct the 'experiment' that already took place. Bill Nye was right to cite CSI as an example of how these facets of science complement each other. If we want to confirm the hypothesis that A killed B, we construct a model to explain data that can be collected after the fact: "We hypothesize that the DNA of this blood sample will match that of the accused, if in fact A killed B, because we know from experimentation that DNA provides a tracer in blood samples that is unique to the individual".

By this approach, we investigate Earth history by making predictions about what kind of data will confirm or disprove our hypotheses. These predictions should be very specific. For example, we can utilize microfossils to predict exactly where in Cretaceous–Paleocene marine sediments there will be a spike in Iridium concentration, based on the hypothesis that it was caused by a meteor impact. Likewise, we could already predict the age of the Chicxulub meteor impact associated with this Iridium anomaly, based on radiometric dates of igneous rocks at the Cretaceous/Paleocene boundary. Similarly, if you were to analyze pollen concentrations within post-glacial lake sediments of Europe, one could predict exactly at what depth those concentrations would shift, based solely on the radiocarbon dates of their organic constituents. Why? Because geologists have reconstructed climate anomalies such as the "Bølling-Allerød warming" and the "Younger Dryas cooling" and constrained their age. Using this model, we can also predict where and why oxygen-isotope values in ice cores from the Greenland Ice Sheet shift abruptly, simply by counting the annual layers of ice back to the proposed events.

“Molecules to man evolution has nothing to do with developing technology”

Ken Ham is nearly right: applied physics and chemistry can generally operate without ascribing to one model of human origins over another. But so what? This does not address the topic of the debate. Further, he does a great injustice to science implying that only applied sciences are valid. Theoretical and historical aspects of each field are vital in forming the solid foundation on which applied sciences operate. When it comes to technology, only very specialized fields within neuroscience, physiology, immunology, etc. are likely to be informed by evolutionary theory. But advances in evolutionary biology and 'old-Earth' geology have given us ample motivation and guidance in developing technologies that aid the historical sciences, from DNA sequencing to seismic surveys of the Earth's crust.

“We all have the same evidences; it’s a battle over how we interpret the past. It’s really a battle over worldviews and starting points.”

As predicted, Ken Ham devoted much of his time to this assertion. This put Bill Nye in the uncomfortable dilemma of switching to a philosophical debate or avoiding the topic altogether. Though it probably counted against him, Nye did the right thing in not trying to debate the veracity of Christian theism or the trustworthiness of the biblical record. Again, the topic of the debate was not "Who has the correct philosophical worldview/starting point?" but "Is Ken Ham's creation model scientifically viable?" Likewise, Ken Ham's discussion on the moral implications of evolution, the prospect of salvation, the purpose of life, and even the justification of laws of logic/nature in a naturalistic worldview were completely off topic. Even if Bill Nye had conceded that science lacks epistemological grounds and morality lacks authority without Christian theism, Ken Ham still would not have answered the question of the debate.

“Based on the Bible's record of history, I can predict that billions of dead things would be buried all over the earth; that’s what we find...”

Ken Ham is not alone in using this oft-repeated mantra to support his claim that the creation model makes accurate predictions. It lacks scientific rigor, however, and merely demonstrates that his model is but a rationalization of data. How does Ham know specifically that billions of dead things would be buried all over the Earth? Does Genesis provide a population estimate of the animal kingdom? Are we told what percentage of the Earth's surface was covered by ocean before the flood? How much by shallow oceans wherein life can thrive? To what extent were soils developed so as to provide enough nutrients from river runoff to support the planktonic food base? Secondly, why would we expect these life forms to be buried necessarily? Was it not possible that the flood killed but did not bury all organisms in neat, sedimentary layers?

To answer any of these questions, even from the biblical description of the seas 'swarming with life', he must utilize historical science—but as Ham himself claims, historical science is not so scientific. Ken Ham's creation model 'predicts' that we should find billions of dead things buried over the Earth because we've already found billions of dead things buried over the Earth.

Rapid post-flood speciation and the creationist 'orchard'

At several points, Bill Nye challenged Ken Ham to explain how 7,000 pairs aboard the ark could evolve into our modern selection of species in just 4–5,000 years. Nye's calculated rate of 11 new species per day does not accurately reflect AiG's model, since Ham claims that fish, insects, and many other organisms need not be aboard the ark, and these groups represent a bulk of species alive today. Regardless, the speciation rate required by the creationist orchard is astounding—impossible by our current understanding of evolutionary ecology. Not only is the rate unobserved in human history, it is orders of magnitude higher than the fastest known cases of speciation.

Complicating Ham's claim is the fact that most of the animals he envisions on the ark (mammals, birds, reptiles, and other organisms unable to survive in the water) are quite large, with relatively low fertility rates. Speciation occurs 'rapidly' (i.e. observable in human history) only among small creatures that reproduce quickly, like small fish and rodents. Large mammals like elephants, cats, wolves, and horses/camels require many times longer for genetic diversity to accumulate among isolated populations, because they take longer to mature and give birth to new generations. Nonetheless, we find fossils of modern species (i.e. must have been derived from the Ark pair) throughout what Ham must term "post-flood sediments", over a wide geographic distribution.

Some of these mammals, such as mammoths, camels, and sloths, are best known from Ice-Age sediments, particularly in Eurasia and the Americas. Let's take the case of an elephant-mammoth-mastodon 'kind', for which the average generation is ~20–30 years. Most of Ken Ham's researchers suggest that an Ice Age peaked ~400–600 years following the flood. This leaves, at best, 14–30 generations for a single pair of elephant-like creatures to evolve into more than a half-dozen individual species and distribute themselves around the globe. This scenario is absurd even for migratory grazers; do we need also to run the numbers for ground sloths, which populated both North and South America around the same time? [Edit: the number of fossil and modern elephants is far higher than I imply here; for more critiques of post-flood speciation rates in mammals/birds, see also the Natural Historian's articles on Baraminology]

Fossil repositories like La Brea Tar Pits in Los Angeles provide the final nail in the coffin. Not only were North American fauna already diverse by the time of the last ice age, but these species existed in rather large populations. Thousands upon thousands of individuals are encased in these tar pits, which represent but a fraction of the species' geographic extents.

"Tree rings, snow ice, and coral," says Nye

In a nutshell, Nye's list of things older than Ken Ham's universe is solid, but went largely unchallenged throughout the debate. Only in passing did Ken Ham suggest that glacial ice could accumulate 'catastrophically', giving the example of a crashed plane in Greenland being packed under ~250 feet of snow. The example is not relevant, though, since 1) these snow rates are not characteristic for those regions of Greenland/Antarctica where ice cores are obtained; and 2) geologists do not date ice cores by ice thickness, but by counting seasonally driven oscillations in texture and chemistry. So how is it that so many annually layered samples extend beyond ~6,000 years?

If given more time, Ken Ham might claim that multiple layers or growth bands could accumulate in a single year. Although such anomalies are documented, however, they are rare, but Ken Ham must consider them the norm to rationalize these data into his model of history. If such anomalies are the norm, then why don't we observe them today? 'Observational science' provides an excellent opportunity for Ham to test his extraordinary claims, but he avoids the topic altogether, because no observation confirms them.

On a final note regarding ice cores, we know the dating methods are robust, because they have been tested by individual lines of evidence. Lake sediments dated by radiocarbon and speleothems dated by U-Th disequilibrium all yield the same age of climate events found also in the ice cores' isotopic records. Ratios of hydrogen and oxygen isotopes vary within ice sheets due to changes in climate (such as temperature and moisture source). These climatic changes affecting Greenland, for example, also affect continental Europe, where cave and lake records capture the same climatic signal within their own isotopic, geochemical, or pollen ratios. The fact that hundreds of records overlap, despite that they are dated by independent radiometric systems, thoroughly contradicts Ken Ham's claim that annual band counts must have formed anomalously or catastrophically.

Were you there?

I was not personally present to witness every band forming within Antarctic ice sheets—does this matter? Ham's challenge only applies if every event of the past necessarily escapes scientific investigation. We must consider every criminal trial suspect, therefore, if we are to adopt Ham's anti-scientific claim. Although I watched on the internet a live stream of Ken Ham's debate, the debate is now a past event. So was my own birth, come to think of it. Can anyone prove that it ever happened?

Whether dealing with modern experiments or historical investigation, we all interpret the dataset before us. We do not even observe billions of dead things within the rocks; we observe only the shapes and remains of what we argue and interpret to be once living organisms through the historical scientific method. When studying natural phenomena, we apply the scientific method to constrain the objectivity of the observer, but all is yet subject to interpretation. We do not even 'observe' the isotope ratios obtained to date minerals, but we interpret electric signals from collector cups at the end of a vacuum tube. It is the scientific method, therefore, that allows us even to interpret properly modern phenomenon. All science is hermeneutic, and historical science is no giant leap into the unknown.

So no, I was not there. Neither was Bill. Neither were you, Mr. Ham. But that is the beauty of historical science—we can still know the past! Appealing to Scripture does not solidify your case, nor distinguish you from us. Why? Because you must still interpret the written word; you must still apply historical science to reconstruct that written word from its dynamic transmission through time and space. You neither wrote it nor observed it being written. So let's thank God together for historical science, without which we could not even read the Bible.

“You can never prove it’s old, so that’s not a hypothetical... Not using the scientific method.”

This single response by Ken Ham during the Q&A session allows us to declare Bill Nye a winner in this debate. When asked if he would retain faith in God if convinced that the Earth were old, Ken Ham remarked that science could never yield for us a reliable age of the Earth. For Ken Ham, nothing historical is subject to scientific investigation. If that is true, then at last, he has answered the question of the debate:

"Is creation a viable model of origins in today’s modern, scientific era?"

Ham can only defend his position by excluding the creation model from science altogether, as though to say, "No, it's not; but neither is yours."


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Edit: I realized that Jimpithecus, author of the Science and Creation blog, had some very similar impressions of the debate. Read those comments here.

My (unsolicited) advice for Bill Nye: Don't teach the dichotomy!

With only a day left before the big event, I think it unlikely for these words to reach Bill Nye, who will not be scouring the internet for last-minute advice. Nonetheless, I write them for anyone watching the debate, in an attempt to mitigate the confusion that is bound to arise in discourse between Ham and Nye.

Why would there be confusion?

Because for Bill Nye, acceptance of a 4.5-billion-year Earth and the evolutionary paradigm in explaining the history and diversity of life is completely natural; it is a logical consequence of surveying mountains of evidence, available to scientists everywhere. For Bill Nye, an escape from creationism requires only that one see all the evidence in the right light, and I expect him to offer as much of that evidence as possible in the allotted time frame.

Ken Ham, on the other hand, has decades of experience in offering oversimplified explanations that turn Bill Nye's best evidences into the very foundation of young-Earth creationism. Galapagos finches? Mutating bacteria strains? Archeopteryx and Tiktaalik? Hominid lineages? Geomorphology and stratigraphy of the Grand Canyon? Radiocarbon dating? All of these evidences are converted to Ham's own warriors with two-minute soundbites. If you're skeptical of this, just check out the radio miniseries by Dr. John Morris (ICR), entitled "Back to Genesis". In each episode (which rarely exceeded a couple minutes), listeners were persuaded that actually, the fossil record is a problem for evolutionists! Or actually, the Grand Canyon is evidence for a catastrophic flood!

If it sounds as though I'm trying to mock Dr. Morris—I'm not. From the perspective of a YEC audience, his radio show offered a daily supply of hope and rejuvenated faith. It inspired listeners to live out their faith with confidence and joy, and few people complain about joyful neighbors and friends. Unfortunately, his devotional-style commentary of the state of science lacked one thing:

Truth.

I do not doubt the sincerity of Dr. Morris or Ken Ham, but their interpretations of biological and geological evidences are flatly wrong. I say this with confidence, because few propositions in science have been more thoroughly disproven than that of a young Earth and a global catastrophic flood (and keep in mind, the goal of science is not to prove, but to disprove).

But now for the confusion. There is scarcely an evidence for Bill Nye's position that cannot be countered with a short, prepared, even witty retort from Ken Ham. For example:

"Well actually, radiocarbon dating offers more evidence for a young Earth. You see, geological materials like diamonds and coal that are supposed to be millions of years old actually contain traces of radioactive carbon, so they can't possibly be that old! But when you start with Bible's claim that a flood recently covered the whole Earth, you don't have to start with the typical assumptions of radiocarbon dating, such as that the atmosphere always contained the same amount of 14C as today. Therefore, we can better understand the results of radiocarbon dating from the perspective of a young Earth modified by a global catastrophic flood!" (my words, not Ham's)

This sort of reply will convince every listener inclined to believe Ken Ham. The problem is that every sentence above contains at least one error, so it would take far longer than 2 minutes for Bill Nye to undo the damage, and that's assuming he's heard these sort of arguments and knows how to respond in the first place.

So here's my brief advice to Bill Nye on how to get the most out of this debate:

1) Most importantly, don't teach the dichotomy! The primary reason that many Christians (myself included) reject young-Earth creationism is not that it lacks scientific merit, but that it is unbiblical. As many of Ham's supporters demonstrate, the conflict with modern science can be distorted, rationalized, or avoided altogether. It is their belief that they champion the orthodox, unadulterated teaching of God's word that fuels their efforts. Unless they are inwardly skeptical of this belief, no scientific revelation will move them to reconsider their position regarding evolution and a young Earth.

You may not be in a position to debate their biblical interpretation, but you can at least remind them that it remains just that: an interpretation. The text of scripture requires no less scientific rigor to understand fully than layers of fossiliferous rock, and the YEC's inability to reconstruct Earth history rivals their inability to tackle ancient literary masterpieces. In fact, the fundamental flaws are nearly identical, as YEC's approach the Bible, rocks, and DNA all with a strong confirmation bias; their conclusion is already in hand, and new data are interpreted to support what they think they already know. It pains me to hear YEC's described as those who ascribe to a 'literal' interpretation of scripture, because their approach is anything but literal, ignoring much of the literary, cultural, and historical contexts of the letter. As a result, their interpretations tend to be shallow, anachronistic, and oversimplified. These characteristics are elucidated when pressed to explain the details of the biblical text in light of their hypothesis, which force them into absurd conclusions (reductio ad absurdum, in a nutshell).

What most young-Earth creationists do not realize is that their nuanced view of scripture is relatively modern and may scarcely be called orthodox. It was largely rejected even by American fundamentalists at the beginning of last century, so it seems improper to call Ken Ham a fundamentalist due to his views on creation. Neither do they represent the mainstream of Christian views on creation, particularly among theologians and other scholars of religion and/or ancient literature. This is not a debate between biblical and non-biblical explanations of origins, but an examination of a new, religious movement with a very American flavor. Please, Mr. Nye, don't propagate the false dichotomy between evolution and the Bible.

2) Be sure to define 'evolution', and stick to that definition. For Ken Ham and his supporters, evolution refers not simply to an explanatory framework of biological and geological data, but to a complete worldview, comprised not least of metaphysical naturalism (i.e. atheism). With regard to its application in biology, do not conflate natural selection with the points of evolutionary theory rejected by Ham. Ken Ham does not deny that natural selection plays an important role in the diversity of life and survival of species through adaptation. In fact, he even accepts that speciation is responsible for the existence of most terrestrial animals and plants today (because otherwise, he can't fit all the animals into the Ark). As far as I know, there is even an exhibit in the Creation Museum devoted to explaining rapid speciation/evolution of animal kinds shortly after the flood. You have an opportunity here to expose the inconsistency on Ken Ham's part in accepting evolution so long as it helps his cause. Moreover, you can challenge the explosive rates at which he suggests that evolution took place in the past. Multiple species of large mammals arising from one pair within a few hundred years and distributing themselves across the globe? Hmm...

3) Despite that the prevalence of young-Earth creationism hinders public trust in and appreciation for science, don't pretend that all young-Earth creationists are ignorant of science and how to apply it. This debate will quickly degrade into a battling appeal to authority as names are given of this scientist or that, who believes this paradigm or that. Further, there is no point in discussing how many scientists reject Ken Ham's view or how few peer-reviewed publications support it. In such an exchange, Ken Ham need only appeal to a worldview/faith bias among the vast majority of researchers and editors, and he can sell this point well. Unless you are willing to engage the underlying philosophical mechanisms that drive and maintain scientific consensus (which is beyond the scope of this debate), you will not be able to respond to his appeals effectively, let alone in a language your audience can understand.

4) Don't let Ken Ham fall back on his mantra that 'evolutionists' and creationists simply approach the same evidence from different starting assumptions or authorities. What he is describing rather is a set of multiple competing hypotheses, which are not resolved by debating whose basic assumptions are better (e.g. naturalism vs. supernaturalism). Multiple competing hypotheses are resolved by formulating mutually exclusive predictions, and then collecting the data required to test the predictions of respective theories. Ken Ham is offering a testable hypothesis, but he will work as hard as possible to prevent you from actually testing it.

5) If and when you do test it, be focused! Undoubtedly, Ken Ham will dance through his list of 2-minute soundbites, and each one that you can't answer in detail will shed doubt on evolutionary theory and count in his favor. Taking the example of radiocarbon from above, challenge him on each individual point before he can move on to another:

You: "Where was it reported that diamonds and coal contain traces of radioactive carbon?"
KH: "In peer-reviewed journals, as well as lab reports from samples that we had analyzed."
You: "But geochronologists that specialize in radiocarbon dating don't believe that these samples are younger than millions of years old. Why not?"
KH: "Well, they suggest that it must be contamination! But these labs take precautions not to contaminate the samples. So if we trust they know how to run a clean lab, then it can't be contamination..."
You: "Yes, they do. But they also admit that no sample can be prepared without being exposed to at least some contamination from the atmosphere. That's precisely the reason for analyzing very old samples of coal and diamonds: to measure the level of contamination during preparation and resulting from electronic or chemical interference during analysis."
KH: "But our geologists believe rather that these samples contain radioactive carbon because they are young. They also believe the radioactive carbon in coal/diamonds is too much to result from radiocarbon."
You: "Did your geologists manage the radiocarbon labs that analyzed the samples?"
KH: "No."
You: "Did your geologists prepare the samples in the radiocarbon lab?"
KH: "No.
You: "Did your geologists design the latest equipment used for AMS radiocarbon dating, or publish papers on background interference and other noise during radiocarbon analysis?"
KH: "No."
You: "Could it be possible that your less experienced geologists, who do not specialize in geochronology, are wrong on this issue?"
KH: "We interpret the same data from a different starting point, so our conclusions are bound to conflict. We consider the effect of Noah's flood on radiocarbon and..."
You: "How much radioactive carbon was in the atmosphere before the flood?"
KH: "We don't know exactly, but probably 500 times less than today."
You: "Was it evenly distributed in the atmosphere?"
KH: "..."
You: "If it was, then all the plants and animals—all the organic matter that you say was buried in Noah's flood and is now contained in layers of sedimentary rock—should appear to be the same age if analyzed by radiocarbon, correct?"
KH: "Yes, they should appear to be much older than they are, because..."
You: "But these samples don't all yield the same age, do they?"
KH: "Not exactly the same age; they range from ~30,000 to 75,000 years."
You: "That is a massive range in radiocarbon activity—almost 8 half-lives! So it's not possible that this radiocarbon all came from the same pre-flood atmosphere, or else the data would be closer together. These data actually falsify the prediction of your theory. But the more fundamental problem is that if there were no radiocarbon activity ever measured in coal or diamonds or any other 'pre-flood' material, you would simply suggest that there was no radiocarbon in the pre-flood atmosphere. This is not at all a scientific approach, and in fact the scientific data conflict with your portrait of Earth history."

This is not a debate for discussing the full range of evidence for or against each other's position, but for exposing the pseudoscientific method by which Ken Ham's worldview must process it. The more detailed the discussion on any given point, the more likely he is to expose that.

I may be asking for a miracle in remaining optimistic about this debate...

But I, for one, believe in them.

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Looking for additional commentary on this topic? Check out this advice from a former creationist (writing for Huffington Post) on the solidarity of the young-Earth paradigm, and why Bill Nye shouldn't underestimate or misjudge his audience.