Uncertainty and Underdetermination in Precambrian Paleobiology — Extinct



There’s one very last thing to mention. A number of of the opposite preservational morphs of Aspidella have names that are supposed to now be acquainted. Those come with Ediacaria (Sprigg’s unique “jellyfish”) and Spriggia, which Glaessner interpreted as a medusoid. Certainly, as Gehling et al. write, “As soon as the Aspidella morphs had been retrodeformed [restored to their original forms], they can’t be outstanding from different Ediacaran discoidal taxa, and can be recognized variously as Ediacaria, Cyclomedusa, Spriggia, Tirasiana, Irridinitus, or Planomedusites if present in different Ediacaran websites around the world” (442). The realization, once more, is that those names pick other areas of a morphological continuum, during which a variety of fossil buildings are produced by means of variations in frame dimension and sedimentary prerequisites.

That is how the “Age of Jellyfish” ends. No longer with a bang however a whimper.

References

Dunn, F.S. and Liu, A.G. (2019). “Viewing the Ediacaran biota as a failed experiment is unhelpful.” Nature Ecology & Evolution 3:512–4.

Fortey, R.A. (1997). Lifestyles: An Unauthorized Biography. London: HarperCollins Publishing.

Gehling, J.G. (1990). “The case for Ediacaran fossil roots to the metazoan tree.” In B.P. Radhakrishna (ed.), The Global of Martin Glaessner, 181–224. Bangalore: Geological Society of India.

Glaessner, M.F. (1959). “Precambrian Coelenterata from Australia, Africa and England.” Nature 183:1472–3.

Glaessner, M.F. (1961). “Pre-Cambrian animals.” Clinical American 204:72–8.

Glaessner, M.F. (1984). The Crack of dawn of Animal Lifestyles. A Biohistorical Find out about. Cambridge: Cambridge College Press.

Glaessner, M.F. and Wade, M. (1966). “The past due Precambrian fossils from Ediacara, South Australia.” Palaeontology 9:97–103.

Gould, S.J. (1989). Superb Lifestyles: The Burgess Shale and the Which means of Historical past. New York: W.W. Norton & Co.

Narbonne, G.M. (2003). “The Ediacara biota: Neoproterozoic foundation of animals and their ecosystems.” Annual Overview of Earth and Planetary Science 33:421–42.

Runnegar, B. (2021). “Following the good judgment in the back of organic interpretations of the Ediacaran biota.” Geological Mag. doi.org/10.1017/S0016756821000443.

Seilacher, A. (1984). “Overdue Precambrian and Early Cambrian Metazoa; preservational or actual extinctions? In H.D. Holland and A.F. Trendall (eds.), Patterns of Alternate, 159–68. Berlin. Fed. Republic Ger.

Seilacher, A. (1989). “Vendozoa: organismic building within the Proterozoic Biosphere.” Lethaia 22:229–239.

Seilacher, A. (1992). “Vendobionta and Psammocorallia: misplaced structures of Precambrian evolution.” Magazine of the Geological Society, London 149:607–13.

Leave a Comment