In the debate, Bill Nye pointed out several indicators that suggest an old age of the earth:
- Ice cores
- Tree rings
- Radiometric dating
- Distant starlight
Ken Ham’s consistent response to these challenges was that any effort to understand the past is “historical science” based upon assumptions and therefore unreliable. You can hear him saying it throughout the debate, and I recommend that you watch 50 seconds starting at 1:41:47. You can click here to start the video at that time, and then you can stop around 1:42:35 when he starts speculating about how lion’s teeth may have been designed to rip into fruit.
It’s true that there’s a difference between repeating an experiment (observational science) and testing evidence for a past event (historical science). I believe Ham drives that distinction way too far and misrepresents how science works in general. Let’s look at two of the indicators Bill Nye referenced and examine the assumptions behind them and the arguments Ken Ham used against them.
Ice core samples have been shown to have as many as 680,000 layers, and evidence suggests these layers represent summer/winter cycles and therefore were produced annually. Ham, as you saw in the clip, responded that it’s an assumption that the layers are annual, and that you can’t know because you weren’t there to see them form. It’s of course true that we didn’t see them, but that assumption is not a wild guess and can be tested and examined so you don’t have to just take the scientists word for it. First of all, we can observe that layers are currently produced annually. That’s a good start. Then we can count back and look for evidence of known events at certain years and see if the layer correctly corresponds to an annual time table.
Volcanic eruptions, for example, can be used to independently test if the layers are annual. When some of the sulfate and ash from an eruption settles in the ice, it leaves a detectable mark in that layer. These markers in the ice align with known eruptions in recent history, and those in the past which were dated using radiometric methods on geological samples before ice core samples were ever taken. If the layers were anything but annual, such diverse data points wouldn’t line up at all. Instead, we see a perfect match. For example, the Tambora Eruption in 1815 launched so much sulfate in the atmosphere that it caused the “year without summer,” which is documented all around the world due to its disastrous impact on harvests. A huge spike of sulfate can be found at the layer dating to 1815 on every ice core ever analyzed anywhere on the planet! This is only one eruption among many, and volcanic evidence is only one independent line among several (cosmic rays, methane, iridium, and radioactive particles from nuclear bomb tests to name a few). Such multiple attestation strongly backs up the interpretation that the layers are annual, so to argue otherwise would require even stronger lines of evidence.
Ham tried to dismiss the data for an annual rate by introducing the irrelevant fact that a plane that crashed in Greenland was covered in a lot of ice in a relatively short period of time. This is irrelevant because scientists aren’t measuring the thickness of the ice to calculate the years, they are measuring the layers which show the passing of seasons each year. These layers vary in depth depending on the year’s climate and precipitation, so no scientist would even consider estimating the passing of time simply by measuring depth as way Ham seems to imply.
Although this process is part of “historical science”, the assumptions are very well-supported and verified with several independent lines of data across multiple disciplines. I agree with Nye that it’s completely unreasonable to deny the conclusion that one layer is formed every year. Ham’s attempt to dismiss it falls flat, and he does not propose any competing explanation for how 680,000 layers could form in 4,000 years.
You can read about how ice core dating can be verified here and here.
When dealing with radiometric dating, we find the same shortcomings in Ham’s attack. Here he tries to rule out the entire process by citing two examples where dating methods produced strange results. Since the methods and assumptions involved in radiometric dating are more complicated and difficult to explain, it’s easier to cast doubt here, particularly when addressing a general audience rather than scientists. Throughout the debate and all over the website of his organization, Answers In Genesis, Ham implies that the expensive labs and scientists involved in radiometric dating are turning out inaccurate and apparently random numbers that mean nothing. The two examples he used to back this insinuation do not hold up to scrutiny.
The first one was that wood dated 45 thousand years old using carbon dating was found within volcanic rock dated 45 million years old using potassium/argon dating. Bill Nye took one wild guess to explain it (as the geochristian points out, Nye’s response was weak), but also said there are a number of explanations more reasonable than concluding that radiometric dating simply doesn’t work. He’s right in that there are lots of reasons why a sample could produce an incorrect result, and scientists are constantly trying to improve their methods and reduce this occurrence as geologists also try to extract the best samples and use multiple testing to get it right.
In the case of the “young” wood in the old lava, Nye should have noticed right away that the results lie beyond the recommended range of carbon dating. A reading of 45,000 years using carbon-14 should always be viewed as suspicious – even more so if it was done 20 years ago (the technology has improved greatly since then). The results that came back from the labs were inconsistent and inconclusive due to the very small amount of carbon detected which is well within the range of error and could easily have been the result of contamination. The results only show that radiocarbon dating wasn’t the right tool for the job and/or the samples were not ideal. This isolated finding does not in any way challenge the entire enterprise of radiocarbon dating. It’s been shown to be reliable again and again when used properly within the recommended ranges. It’s interesting to note that Bible scholars employ this dating method to date manuscripts and defend the integrity of the transmission of Scripture.
For a more detailed, scientific explanation which examines the original report and methods, check out this post from a Christian geologist.
The second example was a lava dome at Mt. St. Helens which was created in the 1980′s and was dated as 360,000 years old using potassium/argon (K-Ar) dating. I’m surprised to see that this clunker is still in use given that it’s been soundly and repeatedly debunked. It’s obvious that the age is known to be far out of the range of reliability. At the time that measurement was taken, the lab that was used didn’t recommend K-Ar for any rocks under 2 million years old. A state of the art lab today can only date rocks older than a few thousand years, and that’s through using Ar-Ar dating. Since the eruption was known to have occurred only 10 years prior, that particular dating method was clearly the wrong tool for the job, and the result of 360,000 years would have surely come with a disclaimer since that lab stated that a reading of less than 2,000,000 years would be unreliable. Again, the problem is the sample is far too small. It would be like conducting a large poll and only hearing back from three people. The results are obviously inconclusive and this in no way reflects upon the reliability of other polls that are applied properly.
For a more details explanation which highlights the many problems with the sample and analysis, check out this post.
So why would someone use K-Ar dating for a sample known to be only 10 years old? It seems likely that the goal all along was to discredit radiometric dating, especially when you realize that both of the examples were the work of Young-Earth creationists working for creationist organizations (Snelling and Austin, respectively). With the evidence in their hands, as well as control of releasing the lab results, it’s no surprise that they’ve managed to come up with a few red herrings. It’s ridiculous to use such flimsy examples to counter the enormous amount of evidence confirming the general reliability of these techniques. The science of radiometric dating continues, labs are being built and upgraded, methods are being evaluate, improved, and developed, and oil companies and archeologists continue to rely on these results. Such “challenges” are baseless.
Rather than dismissing the hard work of scientists in these fields, it would be more beneficial to ask them to explain the reasoning and research behind these assumptions. It’s fascinating and enlightening, and clearly an impressive scientific process. Overturning such a body of work requires at least as much diligence and would be welcomed by the scientific community and awarded with a Nobel prize.
Against these scientific techniques, Ham explains his dating system in the debate. It seems simple at first: six days of creation plus the time of the genealogies up to the birth of Christ. As my previous post mentioned, Ham makes many assumptions here in his interpretation of the Bible:
- Genesis is written to convey scientific and historic truths
- The genre of Genesis 1 specifically is historic narrative, not poetry or symbolism
- The writings have been perfectly preserved, transmitted, and understood
- There is no lapse of time between the earth’s state “without form and void” and the 6 days of creations
- The word “yom” should be understood as a 24-hour day in these instances
- No time passes between any of the listed days
- Adam and Eve fell immediately, with not notable amount of time passing while living in the garden
- There are no gaps in the genealogies
Given that there is reason to doubt many of these assumptions, and scholars and theologians have disagreed throughout history, it’s strange to me that Ham would be so confident in his understanding of each of these against all of the scientific data. Unlike assumptions about ice cores and tree rings, these lack independent verification and are instead in conflict with all other known dating methods. These assumptions date the earth as 6,000 years old, but no other line of evidence makes the same measurement. None. Even though the Young-Earth model holds that everything in the universe is only 6,000 years old, no dating technique developed by them or anyone else yields that specific age for anything. That reality has led many faithful, devoted Christians to reevaluate their assumptions in interpreting Genesis evidence and accept the overwhelming testimony of nature that the earth is indeed very old.
