Dickinsonia

Dickinsonia is an iconic Ediacaran fossil of unknown identity. Dickinsonia has been proposed to be a giant protist, a cnidarian, a segmented worm, or even a lichen (Coutts, Delahooke, and Liu, n.d.). Cholesteroid molecules have been reportedly found in a Dickinsonia fossil (Bobrovskiy et al., 2018), but another report says such molecules may be present in many Precambrian rocks and not necessarily associated with the fossil (Love & Zumberge, 2021). It is considered to be a probable animal (listed as such on the Paleobiology Database), based in part on the cholesteroids, but even that is somewhat uncertain. Usually, only the imprint of the organism is preserved, but a few casts have also been found. The slab containing this specimen (top right corner, see close-up below) is from Ediacaran rocks of the White Sea region of Russia. Other Ediacaran organisms are found on the surface of this slab in relatively close proximity, particularly two specimens of Albumares.

Detail enlargement of Dickinsonia from top right of fossil slab

References:


Bobrovskiy, I. et al., 2018. Ancient steroids establish the Ediacaran fossil Dickinsonia as one of the earliest animals, Science, 361(6408), pp. 1246–1249. doi:10.1126/science.aat7228.

Coutts, F., Delahooke, K. and Liu, A., no date. www.Ediacaran.org. Available at: http://www.ediacaran.org/ (Accessed: August 2024).

Love, G.D. and Zumberge, J.A., 2021. Emerging patterns in proterozoic lipid biomarker records: Implications for marine biospheric evolution and the ecological rise of eukaryotes. Cambridge, United Kingdom: Cambridge University Press. Print.

Paleobiology Database, No date. Dickinsonia. Available at: https://paleobiodb.org/classic/basicTaxonInfo?taxon_no=4717 (Accessed: August 2024).