[Rockhounds] Are sponges a major source of Neoproterozoic C30 steranes?

[Paul]

Great virtual talk about using biomarkers to determine the
presence of sponges in the Neoproterozoic.

What are the major sources of Neoproterozoic C30 steranes?
Gordon Love, University of California, Riverside
Virtual Seminars in Precambrian Geology, December 2, 2021
https://www.youtube.com/watch?v=cfS6tGMdr6E
https://www.youtube.com/channel/UC-mxePnmA2Lchjn_gm7O06g/videos

In addition, starting at 53:30, Dr. Love presents very specific 
arguments about
why cholestane biomarker recovered from fossils of White Sea Dickinsonia
fossils are Holocene contaminates and are not in any way associated with 
them.
If so, this renders the arguments about whether the cholestane biomarker
indicates Dickinsonia is an animal rather moot.

A Fossil Forum post is “Dickinsonia steroids not unique to animals.”
http://www.thefossilforum.com/index.php?/topic/89008-dickinsonia-steroids-not-unique-to-animals/&tab=comments#comment-969547

The original papers are:

Bobrovskiy, I., Hope, J.M., Ivantsov, A., Nettersheim, B.J., Hallmann, 
C. and
Brocks, J.J., 2018. Ancient steroids establish the Ediacaran fossil 
Dickinsonia
as one of the earliest animals. Science, 361(6408), pp.1246-1249.
https://www.researchgate.net/publication/327784781_Ancient_steroids_establish_the_Ediacaran_fossil_Dickinsonia_as_one_of_the_earliest_animals

Retallack, G.J., 2022. Damaged Dickinsonia specimens provide clues to
Ediacaran vendobiont biology. Plos one, 17(6), p.e0269638.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0269638

More of Bobrovskiy’s papers.
https://www.researchgate.net/profile/Ilya-Bobrovskiy/

More of Rettalack’s papers.
https://www.researchgate.net/profile/Gregory-Retallack

Yours,

Paul H.