Do Fossil Counts Match Sediment Counts?
If evolution is true, the number of species coming and going should track the number of rock layers in which they are fossilized, at least roughly. The more sediments per unit time, the more new genera should arise within them. Shanan E. Peters (U of Michigan) decided to test this “novel” approach with marine fossils (the most abundant in the fossil record) over most of the geologic column, from Cambrian to Pliocene, and did indeed find a correlation. He wrote his conclusions in PNAS.1
Peters compared two databases: one that counted genera of marine organisms in the worldwide geologic column, and one that counted rock sections in the geologic column in the USA. (A section is a record of continuous sedimentation bounded by gaps, or unconformities.) First, he graphed genus richness against rock quantity; these measurements correlated well until the Cretaceous, when they diverged sharply. The divergence, he explained, could have been a statistical artifact of sampling called the “pull of the recent”; i.e., the tendency for recent epochs to be better represented than ancient ones. That’s OK, he explained; one would expect the correlations to be seen better at macro rather than micro scales. Second, he graphed first and last appearances of genera against the bottoms and tops of rock sections. These correlated fairly well for extinctions (r=0.75), but not as well for originations of genera (r=0.54 or less). “This finding means,” he tells us, “that the average longevity of a genus in the fossil record is comparable with the average duration of a sedimentary section. In fact, the entire frequency distribution of genus longevities is remarkably similar to that of section durations.” Third, he compared genus turnover with section turnover and also found similar positive correlation, though with some data points as prominent outliers. In his concluding discussion, he tried to explain what these correlations mean.
These results demonstrate that the temporal distribution of genus first and last occurrences in the marine animal fossil record is intimately related to the temporal continuity and quantity of sedimentary rock. Determining why this result is the case is more challenging than demonstrating that it is so. (Emphasis added in all quotes.)
Since the two databases (genus counts and section counts) were presumed “as independent as two data sets that share the same timescale could possibly be,” he felt the correlations, rough as they were, indicated something significant. Either the results were artifacts of preservation bias (the luck of the fossilization process), or had a common-cause relationship. The former, he argued, seems unlikely: “Thus, if stratigraphic correlation and the shared timescale are the only reasons for statistical similarity, then virtually all temporal patterns derived from the geologic record must be little more than methodological artifacts of binning and correlation. This possibility seems extremely unlikely (although quantifying the magnitudes of the statistical contributions of these factors is very important).” That being agreed, which explanation – selection bias or common cause – best explains the data?
Assuming that macroevolutionary patterns derived from genus first and last occurrences have the potential to be meaningful in a biological sense, the task then becomes to explain why patterns in the genus fossil record are closely duplicated by analogous patterns in the sedimentary rock record. As discussed above, there are two possibilities, (i) preservation bias and (ii) shared forcing mechanisms (common cause).
He showed that the latter possibility makes better predictions, but does admit one caveat: “because only unconformity and rock quantity biases are being measured here, it is possible that facies biases and/or asymmetries in environmental preservation within sedimentary sequences are causing the stronger section-genus extinction correlation”; i.e., the beginning and end of the story don’t always reveal what happened in the middle. Nevertheless, he felt confident that taxonomists and geologists had not conspired to bias the conclusions: “it seems unlikely that the work of hundreds of taxonomists has been so nonrandom as to render the survivorship patterns of >32,000 genera from across the tree of life little more than a quantification of the structure of the sedimentary rock record.”
Why, however, would the genus extinction count correlate with the end of the rock section better than the origination count correlate with the beginning? Aha, the common-cause hypothesis predicted it would. The answer is in the way evolution works:
Under the common-cause hypothesis, however, genera are expected to originate early in a sedimentary basin’s history as new habitats and environments expand and to go extinct abruptly when environmental changes eliminate the basin environments altogether. Thus, similar average durations for sections and genera as well as corresponding peaks and troughs in rates of origination and extinction are expected. Interestingly, the common-cause hypothesis also predicts that the genus-section extinction correlation should be stronger than the genus-section origination correlation because genus extinction can match the timing of rapid environmental shifts that result in section truncation, whereas genus origination may not be capable of responding instantly to the macroevolutionary opportunities afforded by basin expansion. This possibility is sensitive to choice of timescale, but it is supported by analyses that find less empirical support for pulsed genus origination [i.e., punctuated equilibria] than for pulsed genus extinction at the same level of temporal resolution in the Phanerozoic.
The remainder of Peters’ discussion delved into the meaning of these correlations for theories of environmental forcing of macroevolution and timing of mass extinctions. He favored gradualism over saltation for origination of species, and discounted the need for major catastrophes to explain extinction rates. He defended the challenging concept that “much of the macroevolutionary history of marine animals is driven by processes related to the formation and destruction of sedimentary basins.” If some evolutionists believe that extinctions and explosions of biological diversity can be forced by a meteorite impact, for instance, why not consider the possibility that macroevolutionary change can also be forced by slower geological changes? Thus, “it would seem prudent to revisit some of the classic unifying hypotheses that are grounded in the effects of continually operating processes and to reevaluate seriously the extent to which unusual or episodic events are required to explain the macroevolutionary history of marine animals.”
In conclusion, he admitted that more work will need to be done to rule out taxonomic biases. These “remain a potential obfuscator of macroevolutionary patterns in all global taxonomic databases,” he says; though he has shown some correlation, he is not trying to push his point too far. “Further quantifying the relationships between the large-scale temporal and spatial structure of the geologic record and the distribution of fossil occurrences within this structure will be important,” he ended, “in overcoming persistent sampling biases and in testing the extent to which common-cause mechanisms have dominated the macroevolutionary history of marine animals.”
1Shanan E. Peters, “Geological constraints on the macroevolutionary history of marine animals, “ Proceedings of the National Academy of Sciences USA, August 30, 2005, vol. 102, no. 35, 12326-12331, published online before print August 16, 2005, 10.1073/pnas.0502616102.
This lengthy entry is exhibited here to show how evolutionists can fool themselves into thinking the observations support Charlie’s tall tale. In the first place, he used evolutionary assumptions to calibrate evolutionary assumptions: the “common timescale” of both databases is the geologic column, a theoretical arrangement of global sediments built on the assumption of evolution and millions of years. This is reminiscent of the joke about the church bell ringer who set his watch by the clock tower on the parliament building, only to find out that the clock tower maintenance man set his clock by the church bell. Second, the correlations are only marginally significant. His charts show severe outliers. Sometimes the anomalous data points have an important story to tell. Third, his use of gap-bound rock sections only concentrates on the beginning and ending of continuously-deposited sediments. In the old Dr. Seuss book The Cat in the Hat, the first and last pages of the book, showing the children contentedly at ease in a clean living room, belies all the chaos and commotion that occurred in the middle. Last, Peters trusted in the “if you build it, they will come” theory of evolution. He didn’t explain how new genera of marine organisms would “emerge” when the sea level rose or fell; he just assumed that whenever organisms are given a safe haven, presto! macroevolution happens. In short, the evolutionary story rigged, controlled, operated and guaranteed the outcome of the entire analysis. Evolution is a self-fulfilling prophecy.
For a side dish, consider what EurekAlert recently reported: most scientific papers are wrong. Whether from financial interest, prejudice, unseen biases, conflict of interest, peer pressure or the desire to prove relationships that don’t exist (false positives), “There is increasing concern that in modern research, false findings may be the majority or even the vast majority of published research claims.” Iain Murray, writing for Competitive Enterprise Institute, reflected on what this means – much authoritative-sounding science talk is inconclusive and, frankly, politically or selfishly motivated. The paper by Peters, reviewed here, fits the description. For all its graphs and jargon, it is trying to prove something that isn’t necessarily true, built on a bias for a certain brand of Darwinian evolution.
Even if there were a correlation between sediment counts and genus counts, could there be a non-evolutionary explanation? Naturally. In a flood scenario, for instance, more genera are likely to be buried in sediments corresponding to the volume of the material. The first appearance of a genus would either represent the chance placement in the layers or a mechanical artifact of the burial process, such as liquefaction or hydrodynamic sorting. Extinction would occur, but not origination by evolution. No great time periods need transpire. Since Peters’ radar screen was not tuned to this possibility, he missed it.