Let's study ID: an expected early Cambrian found (Introduction)

by David Turell @, Thursday, October 28, 2021, 14:52 (30 days ago) @ dhw

Molecular clocks predicted it:

https://www.nature.com/articles/s41586-021-04033-w?WT.ec_id=NATURE-202110&sap-outbo...

"The Cambrian fossil record chronicles in exceptional detail the emergence of major bilaterian clades and continues to provide chronological constraints on the evolutionary diversification of disparate metazoans from a common ancestor. Nearly all animal phyla, including soft-bodied Deuterostoma, Entoprocta, Phoronida and Priapulida, made their first appearance during the Cambrian evolutionary radiation. A key exception is the ‘missing’ colonial lophotrochozoan phylum Bryozoa, in which six of the eight recognized orders belonging to the classes Stenolaemata and Gymnolaemata appear abruptly with considerable diversity during the early Ordovician period6. Furthermore, there is a major time gap (approximately 44 million years) between the first fossil record of unequivocal bryozoans in the earliest Ordovician (Tremadocian) and the deeper origination in the early Cambrian (Terreneuvian) estimated using modern molecular clock analyses.

***

"Here we describe rare but exquisitely preserved specimens of a millimetric modular fossil, Protomelission gatehousei9 from the early Cambrian of Australia and South China (Extended Data. Scanning electron microscopy and X-ray tomographic microscopy, Extended Data images reveal a combination of character traits that suggest a stem-group bryozoan affinity for P. gatehousei but distinguish the taxon from all extant and extinct clades. The interpretation of this secondarily phosphatized fossil from lower Cambrian rocks of South China and South Australia as a putative bryozoan indicates that modular bryozoans evolved synchronously with most other stem-group metazoans during the Cambrian evolutionary radiation."

Comment: All our existing animal phyla started in the Cambrian. Now it is shown this one is also. Fitsv tehv existing pattern of timed design.


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