For more than seventy years it was the scientific consensus and undisputed textbook wisdom that the origin of multicellular life in the late Precambrian was triggered by increased oxygen levels (Fike et al. 2006, Sahoo et al. 2012, Lyons et al. 2014, Reinhard et al. 2016, Anonymous 2023, Harrison 2023, Ralls 2023, UCPH 2023). For example, McFadden et al. (2008) identified two pulses of oxidation in the Precambrian and found that “following this second oxidation event, between 550 and 542 million years ago, there was a worldwide increase of Ediacaran organisms, complex macroscopic life forms, an event recently dubbed the Avalon Explosion” (Virginia Tech 2008). Similarily, the study by Pogge von Strandmann et al. (2015) was promoted in a press release as demonstrating that “oxygen provided breath of life that allowed animals to evolve” (Hickey et al. 2015).
Now a new study (Ostrander et al. 2023) by group of researchers from Denmark has overturned decades of evolutionary dogma and claims the exact opposite: “oxygen didn’t trigger multicellular organisms” (Anonymous 2023, UCPH 2023). What this study found was instead clear evidence of a lower oxygen content correlated with the Avalon Explosion of the Ediacaran biota. The authors summarize their surprising findings as: “Contrary to a classical hypothesis, our interpretations place the Shuram excursion, and any coeval animal evolutionary events, in a predominantly anoxic global ocean.” Co-author Christian Bjerrum commented “Specifically, it means that we need to rethink a lot of the things that we believed to be true from our childhood learning. And textbooks need to be revised and rewritten. So, if not extra oxygen, what triggered the era’s explosion of life? Perhaps the exact opposite” (Anonymous 2023, UCPH 2023). Some even went further and suggested to “forget everything you thought you knew about how life evolved on Earth” (Ralls 2023) because it “turns out we might be very wrong about how life arose on Earth” (Harrison 2023).
Communication from a Paleobiologist
Incidentally, a few days ago I received a personal message from my paleobiologist colleague Dr. Ken Towe, a retired former senior scientist at the Smithsonian Institution, who had read a recent article of mine at Evolution News on the Cambrian Explosion (Bechly 2023). He suggested that he has found a solution to the problem of the sudden appearance of complex body plans in the Cambrian, which supports the biological and biochemical evolution needed to make the multicellular connective tissues and the strengthening required for the larger higher forms of life to suddenly appear. His hypothesis (Towe 1970, 1981, also see: Saul 2009) is basically that two entirely new amino acids (i.e., hydroxyoeoline and hydroxylysine), which are required for the formation of structural glycoproteins such as collagen in metazoans, could only form under oxygen rich conditions and that explains the late origin of complex multicellular life after the “boring billion” of only bacterial and protist life. Towe (1981) also suggested in his article that multicellular life prior to the Cambrian Explosion was restricted to “small, thin, diffusion-limited organisms unlikely to be found preserved as fossils,” which is nothing but a version of the artifact hypothesis that was addressed and debunked by Stephen Meyer (2013) in his book Darwin’s Doubt. Towe’s hypothesis is certainly interesting but, in my view, it totally fails to solve the problem of the Cambrian Explosion for the following reasons:
- The availability of the two new amino acids may be a necessary condition for complex multicellular life but certainly not a sufficient condition to explain the sudden origin of numerous new body plans, which required new genetic code (Paps & Holland 2018) for new proteins, new tissues, and new complex organs as well as new ontogenetic pathways.
- Many Precambrian localities of the Burgess Shale type were perfectly able to preserve Ediacaran soft-bodied small precursors of the Cambrian Explosion animals but still they remain elusive (Bechly 2020).
- As we have just seen above, new research suggests that, contrary to seventy years of Darwinian consensus science, the appearance of multicellular life did not correlate with higher oxygen content but indeed with a lower one. Also, experimental research had previously challenged the so-called oxygen control hypothesis for the origin of multicellular life (Bozdag et al. 2021, News Staff 2021).
Much Left Unexplained
In a follow up message, Dr. Towe clarified that even this lower oxygen content still supports his hypothesis and matches the predictions in his 1970 study. However, in that case there is no more any temporal correlation between the oxygenation events and the origin of multicellular life, leaving unexplained why the critical amino acids did not originate at earlier times in the Precambrian. Remarkably, Towe concluded his message with the claim that there is nothing “discontinuous” about the geologically sudden appearance of many different preservable species in the fossil record. Really?! Why then did evolutionist paleobiologists call this event the Cambrian Explosion in the first place? Why is it widely considered to be a problem that requires an explanation and not just an artifact?
Here is what Professor Derek Briggs, a world-renowned expert on Cambrian fossils, has to say on this issue: “We now know that the sudden appearance of fossils in the Cambrian (541–485 million years ago) is real and not an artefact of an imperfect fossil record” (Briggs 2015). Likewise, Zhang & Shu (2021) admitted that “multiple sources of evidence are strongly suggestive of a real evolutionary event being recorded rather than an artifact of an imperfect fossil record.” Cabej (2020) put it even more clearly: “Nevertheless, now, 150 years after The Origin, when an incomparably larger stock of animal fossils has been collected, Darwin’s gap remains, the abrupt appearance of Cambrian fossils is a reality, and we are still wondering about the forces and mechanisms that drove it. Despite the fact that, from time to time, a small number of students have questioned the reality of the Cambrian explosion on the same ground as Darwin, today’s consensus is that Cambrian explosion is a scientific fact” (Linnemann et al., 2019). And, “The Cambrian explosion is real and its consequences set in motion a sea-change in evolutionary history” (Conway Morris, 2000; Nichols et al., 2006).
An Unsolved Problem
Since Towe’s attempt fails, just like all other suggested alternatives to explain the Cambrian Explosion (Meyer 2013, Evolution News 2017, 2018, Bechly 2018, Coppedge 2022), the abrupt appearance of animal body plan disparity stubbornly remains an unsolved problem for Darwinism. However, the new research of Ostrander et al. (2023) points to an even bigger problem, which is the dubious scientific status of Darwinian evolutionary theory itself that arguably seems to be compatible with any conceivable observations and thus unfalsifiable and heuristically worthless. If more than seventy years of consensus endorsed increased oxygen as trigger of multicellular life, and then scientists simply cheer for the progress of science (Harrison 2023) when the exact opposite correlation is found, there is something fundamentally wrong with the theory. Demonstration of a grandiose failure of a theory may be scientific progress, but it certainly cannot be forged into a success for this very theory. Maybe it’s time to look for a new theory that better explains the empirical data instead of producing decades of fallacious research.
- Anonymous 2023. Oxygen didn’t trigger multicellular organisms, study claims. Lab+Life Scientist August 3, 2023. https://www.labonline.com.au/content/analytical-instrumentation/article/oxygen-didn-t-trigger-multicellular-organisms-study-claims-936893447
- Bechly G 2018. Ignoring Other Research, New Study Explains (Away) the Origin of New Body Plans. Evolution News September 12, 2018. https://evolutionnews.org/2018/09/ignoring-other-research-new-study-explains-away-the-origin-of-new-body-plans/
- Bechly G 2020. The Demise of the Artifact Hypothesis. Evolution News July 6, 2020. https://evolutionnews.org/2020/07/demise-of-the-artifact-hypothesis-aggravates-the-problem-of-the-cambrian-explosion/
- Bechly G 2023. Fossil Friday: Fossil Tunicate Confirms Cambrian Explosion. Evolution News August 4, 2023. https://evolutionnews.org/2023/08/fossil-friday-fossil-tunicate-confirms-cambrian-explosion/
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- Evolution News 2017. Next on the Cambrian Explosion Gong Show: The Slime Theory. Evolution News September 11, 2017. https://evolutionnews.org/2017/09/next-on-the-cambrian-explosion-gong-show-the-slime-theory/
- Evolution News 2018. Sick of the Oxygen Theory of the Cambrian Explosion? Here’s the Cancer Theory. Evolution News February 6, 2018. https://evolutionnews.org/2018/02/sick-of-the-oxygen-theory-of-the-cambrian-explosion-heres-the-cancer-theory/
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