Fossil Friday: Alleged Precambrian Fossil Unmasked as Rotten Beehive
When the Covid pandemic struck in 2020 a scientific conference in India was cancelled, and some stranded scientists used their unexpected free time as an opportunity for a field trip to the Bhimbetka Rock Shelters in central India, a famous UNESCO World Heritage site of ancient rock art. One of these scientists was paleontologist Gregory Retallack, a retired professor from the University of Oregon and expert on Ediacaran fossils. The Maihar Sandstone rocks of the cave have been attributed to the Upper Vindhyan strata, which are of contentious Precambrian age between 1,600 to 541 million years old (Nature 2021, Kwafo et al. 2023). Retallack noticed strange impressions high up on the walls of the cave, which he identified as three specimens of the fossil Ediacaran organism Dickinsonia. Retallack found that “the fossils are identical with Dickinsonia tenuis from the Ediacara Member of the Rawnsley Quartzite in South Australia.”
This would have represented not just the first record of Dickinsonia in India, but would have also confirmed the younger Ediacaran age of the Bhimbetka rocks and rewritten our understanding of the plate tectonic history of the Indian subcontinent. Retallack published his remarkble discovery with a team of five co-authors in the high-impact journal Gondwana Research (Retallack et al. 2021). The prestigious
journal Nature commented that the “fossil from dawn of animal life found in India’s famous caves … offers insights into the range of emerging complex life” (Nature 2021). Of course, the sensational discovery attracted worldwide media coverage from the New York Times to the Weather Channel.
Isn’t Science Cool?!
Well, earlier this year a new study by a team of scientists from the University of Florida and from India turned the cool science into a real bummer. The scientists revisited the site and discovered that the assumed Ediacaran fossils are neither of Ediacaran age nor represent fossils at all, but are just the recent remains of decayed and fallen beehives. The patterns of remaining wax, where the beehives were attached to the cave wall and fell off, just accidently happened to resemble the shape of Dickinsonia fossils at first glance. That’s a big oopsie. The debunking evidence was so overwhelming (Meert et al. 2023, also see Kwafo et al. 2023 and Pandey et al. 2023) that even the original authors publicly admitted their mistaken identification (Retallack et al. 2023), for which they have even been praised as a kind of heroes of science (University of Florida 2023). Of course, this retraction renders all the grandiose conclusions about the age of the rocks and the paleogeography of India moot as well (University of Florida 2023, Kwafo et al. 2023).
There is another point I would like to mention: It is a common creationist meme often repeated on social media that paleontologists engage in circular reasoning because they date the rocks with fossils and the fossils with the rocks they are found in. This is simply not true in many cases, where different dating techniques like radiometric datings and paleomagnetography supplement biostratigraphic evidence. But the present case also illustrates that the trope is not totally off. Here is what the scientists commented (University of Florida 2023): “Correcting the fossil record puts the age of the rocks back into contention. Because the rock formation doesn’t have any fossils from a known time period, dating it can be difficult.” Read the last sentence again and let it sink in.
Hard Rocks, Soft Science
It is also interesting to note that an old dating of 900 million years and a younger dating of 550 million years are both supported by the same radiometric U-Pb dating technique of Upper Vindhyan zircon crystals (Lan et al. 2020, Nature 2021). So, radiometric methods clearly are not as reliable and precise as many scientists love to think. This does not mean that the consensus geological timeline is totally wrong, but it at least shows that questioning such datings is not irrational either. That renowned scientists can engage in Rorschach play with accidental patterns on rock walls and produce peer-reviewed scientific papers with far-reaching evolutionary conclusions from such pseudoscientific endeavours will likely raise further justified doubts in paleontological evidence for evolution in general. Even though the fossil rocks are hard, the interpreting science often seems to be very soft!
References
Kwafo S, Singha A, Pandit M & Meert J 2023. Reply to the comment by Retallack et al. (2023) on “Stinging News: ‘Dickinsonia’ discovered in the Upper Vindhyan of India not worth the buzz”. Gondwana Research 118, 160–162. DOI: https://doi.org/10.1016/j.gr.2023.02.016
Lan Z, Zhang S, Li X-H, Pandey SK, Sharma M, Shukla Y, Ahmad S, Sarkar S & Zhai M 2020. Towards resolving the ‘jigsaw puzzle’ and age-fossil inconsistency within East Gondwana. Precambrian Research 345:105775. DOI: https://doi.org/10.1016/j.precamres.2020.105775
Meert JG, Pandit MK, Kwafo S & Singha A 2023. Stinging News: ‘Dickinsonia’ discovered in the Upper Vindhyan of India not worth the buzz. Gondwana Research 117, 1–7. DOI: https://doi.org/10.1016/j.gr.2023.01.003
Nature 2021. Fossil from dawn of animal life found in India’s famous cave. Nature India February 17, 2021. https://www.nature.com/articles/nindia.2021.30
Pandey SK, Ahmad S & Sharma M 2023. Dickinsonia tenuis reported by Retallack et al. 2021 is not a fossil, instead an impression of an extant ‘fallen beehive’. Journal of the Geological Society of India 99, 311–316. DOI: https://doi.org/10.1007/s12594-023-2312-2
Retallack GJ, Matthews NA, Master S, Khangar RG & Khan M 2021. Dickinsonia discovered in India and late Ediacaran biogeography. Gondwana Research 90, 165–170. DOI: https://doi.org/10.1016/j.gr.2
Retallack GJ, Master S, Khangar RG & Khan M 2023. Discussion on “Stinging News: ‘Dickinsonia’ discovered in the Upper Vindhyan of India not worth the buzz” by Meert, et al. (2023). Gondwana Research 118, 163–164. DOI: https://doi.org/10.1016/j.gr.2023.02.006
University of Florida 2023. Mistaken fossil rewrites history of Indian subcontinent for second time. ScienceDaily February 1, 2023. https://www.sciencedaily.co
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