As I've pointed out more than once, even though the evidence against YEC (or its close relation old earth young life creationism) is overwhelming, the fact that many Christadelphians still persist in denying reality in order to preserve human dogma means that there is a strong imperative to present as much information as possible in order to show to the rational, intellectually honest, open-minded Christadelphian why YEC / OEYC are untenable viewpoints.
Two recent articles from the always brilliant blogs Naturalis Historia and Age of Rocks provide two more lines of evidence that highlight the folly of YEC / OEYC. Joel Duff, writing at Naturalis Historia shows how the distribution of diatoms in the fossil record completely falsifies what we would expect to see if the entire fossil record had been deposited by the flood. Geologist Jonathan Baker, writing at Age of Rocks shows how multiple independent dating methods, including one that indirectly depends on living creatures, provide a date that exceeds the age that YECs and OEYCs posit for the earliest living creature (and for YECs the age of the Earth itself).
Jonathan Baker's article begins by looking at how stable isotope date in Greenland ice cores provides evidence for a cold snap around 8200 years ago, one that lasted a few centuries:
As the data is consistent from ice cores taken across Greenland, this is evidence for a regional cold snap that occurred 2200 years before YECs claim the universe was created.
Baker correctly notes that this cooling event would have affected Scandinavia. Instead of ice cores, pollen density in lake sediments are used to infer temperature, given that pollen density is a marker of temperature change. Radiocarbon dating is used to provide an absolute date. What do we find? Independent confirmation of the ice core data that shows a cooling event in the region around 8200 years ago. This also falsifies the OEYC argument that all life was created in six consecutive days 6000 years ago (on an old Earth) as we have pollen from plants 2200 years before the OEYCs claim they were created!
Baker continues by observing that another method of inferring ancient sea surface temperature is to look at the chemistry of small shells (foraminifera). Data from foraminifera obtained from sediment cores off Iceland, with absolute dates taken via radiocarbon dates also shows a cooling event around 8200 years ago.
Compelling as this data is, when we use alternative dating methods other than radiocarbon and ice core data, we get more evidence for an 8200 year old cooling event. Baker writes:
Take a look, for example, at the following plot from Wang et al. (2005), which illustrates 9,000 years worth of stable-isotope data from the best-dated stalagmite in the world in Dongge Cave, south China. Take note how many U-Th dates were obtained, as well as the fact that all of the dates (44 in total!) get older toward the bottom of the stalagmite. Isn’t it strange how that works if this radiometric dating stuff is all bunk? In any case, you’ll find the 8.2 ka event clearly expressed in the oxygen-isotope values, which are related to the strength of the Asian summer monsoon (more rainfall results in a more negative δ18O value).
Lastly, let’s take a quick look at Central and South America. You might recognize the name of the first locality, the Cariaco Basin off the coast of Venezuela, because its sediments contain tens of thousands of well-defined varves—another reason to reject the YEC timeline. Whether we count those varves back to ~8,200 years ago or date the sediments directly by the radiocarbon method, there is evidence for a sudden spike in surface salinity associated with the 8.2 ka event (Lin et al., 1997). In other words, the weather on land got drier due to a shift in climate zones, so less freshwater was pouring into the basin via rivers.
In this stalagmite from Costa Rica (lines C and D), the same story emerges from yet another tropical cave—multicentennial drought centered around 8,200 years ago, once more dated by the U-Th method. The timing of that drought corresponds perfectly to arid winds over the Cariaco Basin (line B) and cooling in Greenland (line A):
How did the globe cool abruptly, 2.2 thousand years before it even existed?
So far, we have surveyed only a small fraction of the records from around the world, which document this famed climate event 8,200 years ago. Our methods for reconstructing the past, therefore, are not fundamentally flawed or undermined by so-called ‘evolutionary’ assumptions. The ubiquitous expression of the ‘8.2 ka event’ provides outstanding confidence, rather, in the conventional age of the Earth and the geological timeline.
Let's move onto Joel Duff's argument. Perhaps the most devastating argument against the YEC belief that the entire fossil record was deposited a few thousand years ago (apart from the ancient dates for the fossil record stretching over hundreds of millions of years) is the fact that we do not see modern and ancient life coexisting in the fossil record (remember, YECs argue that Anomalocaris canadensis, Morganucodon watsoni, and Homo sapiens coexisted). The desperate YEC attempts to circumvent this by claiming the fossil record is produced by ecological zoning or hydraulic sorting fall apart when we see that animals that occupy similar ecological niches (ancient and modern fish, ancient and modern birds) are not found in the same fossil strata, while large dense heavy ancient and modern animals are not at the lowest geological strata.
Duff notes how a casual YEC argument on diatoms shows that YEC claims following on from it are readily falsified when we actually look at the fossil record:
Yesterday I came across an article by Dr. Snelling of Answers in Genesis in which he discusses his YEC explanation for the origin of oil and coal. In this case the problem for YECs is how to account for the vast quantities of oil and coal in rocks formed during a global flood. What caught my eye was this section of the concluding paragraph:
Vast forests grew on land and water surfaces in the pre-Flood world, and the oceans teemed with diatoms and other tiny photosynthetic organisms. Then during the global Flood cataclysm, the forests were uprooted and swept away. Huge masses of plant debris were rapidly buried in what thus became coal beds, and organic matter generally was dispersed throughout the many catastrophically deposited sedimentary rock layers. The coal beds and fossiliferous sediment layers became deeply buried as the Flood progressed. From: The Origin of OilDr. Snelling is a geologist and so he might be excused for not knowing much about the fossil record or the ecology of aquatic photosynthetic organisms but one would hope that his article was evaluated by peers prior to publication.
What are the problems here? First, I have highlighted the phrase “oceans teemed with diatoms” for a reason. Earlier this year I wrote an article about the big problem that these tiny diatoms raise for flood geology and the Young Earth paradigm (See. Life in a Glass House: Diatoms Shatter Young Earth Flood Geology). In that article, I talked about glass-house diatoms and where they appear in the fossil record. The key observation, or fact, that we can ascertain from the fossil record is that they don’t appear in the fossil record until the Jurassic Period (See figure to the right). Because they produce a glass case around their cells they are quite well-preserved and thus the lack of them below the Jurassic, or more than 50% of the fossil record, is very significant and cannot be ignored by any model of Earth’s history.
In the Flood geology hypothesis of Earth’s history the rock of the Ordovician through the Cretaceous and maybe even all the way to Neogene are claimed to have been deposited all within a year or few years. If pre-Flood oceans “teemed with diatoms” then the Flood geology model would predict that diatoms should be found throughout all the layers of rock. Yet, we have billions of tons of coal seams that lack diatoms, we have complete ecosystem of aquatic organisms preserved from the Silurian and Devonian and in those same times there are countless trillions of single-celled organisms preserved but no diatoms. See my post on the forams and diatoms on the fossil record for more (Forams and Diatoms: Testing the Young Earth Flood Geology Hypothesis).
Simple observational science should have informed Dr. Snelling that an appeal to an ocean full of diatoms in the pre-Flood world directly contradicts the observed geological record. The lack of diatoms in more than 75% of the geological column is a serious, and still unaddressed, problem for the young earth model.
The logic is simple and unanswerable. If the entire fossil record was deposited in less than one year, why do we not see diatoms in over three-quarters of the record. Furthermore, harking to the YEC attempts to explain what we see in the fossil record, why don't we see such light fossils together in the same strata according to what their theory of hydraulic sorting suggests.
For the OEYC who accept the great age of the Earth, but deny that life on it is older than 6000 years, we have unarguable evidence of life millions of years old. Both YEC and OEYC have been comprehensively falsified, and again, the only intellectually honest position available is to concede that they have been greatly mistaken in their science denial, apologise for inadvertently misleading people and slandering their brothers in Christ who accept the overwhelming scientific evidence, and sit with humility before the evidence to learn more about this ancient, evolving creation.