Fossil fats suggest animal life got started later than previously though

[Oxytropidoceras]

Earliest animals developed later than assumed, Max Planck Society

https://phys.org/news/2019-03-earliest-animals-assumed.html

 

Fossil fats suggest animal life got started later than 

previously thought. New Atlas. Michael Irving, March 7th, 2019

https://newatlas.com/earliest-animals-evolved-later/58771/

 

Nettersheim, B.J., Brocks, J.J., Schwelm, A., Hope, J.M., Not, F.,

 Lomas, M., Schmidt, C., Schiebel, R., Nowack, E.C., De Deckker, 

P. and Pawlowski, J., 2019. Putative sponge biomarkers in 

unicellular Rhizaria question an early rise of animals. Nature 

ecology & evolution, http://dx.doi.org/10.1038/s41559-019-0806-5

 

A related article:

 

Fossil fats reveal how complex life kicked off after Snowball 

Earth phase. New Atlas. Michael Irving, January 31st, 2019

https://newatlas.com/fossil-fats-snowball-earth/58292/

 

yours,

 

Paul H.

[Tidgy's Dad]

Thanks for these.

Fascinating and very important. 

[FossilDAWG]

The whole theory rests on the assumption that sponges are the most primitive animals, and that they gave rise to all other animals.  However not everyone agrees with this idea, and molecular (i.e. DNA) evidence strongly suggests that comb jellies are closer to the ancestral animal.  The simple anatomy of sponges, including lack of a nervous system, may well be due to loss of many organ systems associated with adopting a sessile filter feeding life style.

 

Also the comment about the uncertainty of DNA estimates for the origin of animals ignores a large number of studies that provide much more constrained estimates.  For example, several molecular studies of arthropod phylogeny provide robust estimates of the timing of separation of myriapods (millipedes and centipedes), arachnids (the group including modern scorpions, ticks/mites, and spiders), and several crustacean groups at over 650 million years ago.  These studies are quite robust, being based on comparison of hundreds of genes (or more in some cases) from numerous species from each of several dozen extant lineages of arthropods.  If all these arthropod groups existed 650 million years ago, and animals originated only 560 million years ago (according to the new publication) we have a big problem.  Both hypotheses cannot be true; to me the correct answer is obvious.

 

Don

[Wrangellian]

I thought that 560 number seemed a little too recent, myself. I believe the oldest Ediacaran fossils (Rangeomorphs of Newfoundland) are about 575m.y. Of course it's been debated whether those are animals or something else...

[doushantuo]

some of you may like

 

 

Thi2002a.pdf

Volker Thiel · Martin Blumenberg · Jens HefterThomas Pape · Shirley Pomponi · John Reed Joachim Reitner · Gert Wörheide · Walter Michaelis
A chemical view of the most ancient metazoa – biomarker chemotaxonomy of hexactinellid sponges

Naturwissenschaften (2002) 89:60–66
DOI 10.1007/s00114-001-0284-9

 

 

 

[doushantuo]

a 2009 article from nature:

 

1586 Brocks 2009.pdf

Early animals out in the cold
Jochen J. Brocks and Nicholas J. Butterfield

NEWS & VIEWS NATURE|Vol 457|5 February 2009

 

[doushantuo]

some of you may like:

 

bioma240929.full.pdf

Proposal for practical multi-kingdom classification of eukaryotes based on monophyly  and comparable divergence time criteria
Leho Tedersoo/2017

[doushantuo]

some of you may like:

 

Gold_et_al-2017-Geobiology.pdf

Lipidomics of the sea sponge Amphimedon queenslandica and implication for biomarker geochemistry
D. A. Gold, S. S. O’Reilly J. Watson, B. M. Degnan, S. M. Degnan,J. O. Krömer,| R. E. Summons

Received: 01 May 2017 | Accepted: 17 July 2017
DOI: 10.1111/gbi.12253