This 500-million-year-old algae fossil sheds light on the diversity of life

Protocodium sinense. This is the name of the news. species of algae discovered by paleontologists in the Dengying Formation in southern China. This geological formation, dating to the Ediacaran (−635 to −541 million years ago), contains many fossils dating back more than 500 million years, including the researchers’ latest find: particularly well-preserved three-dimensional algae, detailed in the review BMC biology. This is the first time such ancient fossils have been found in such a state of preservation.

A feat possible thanks to a replacement of the original organic matter, which degrades in normal times, into phosphate! This process can only take place in thecomplete absence of oxygen in decaying tissue. If the latter already contain phosphates, these settle and gradually replace the organic matter.

Combined image showing the outer surface of Protocodium sinense (left), seen through the outer shell consisting of utricles (center, colored) and central siphons (right, colored).  © Cedric Aria

Combined image showing the outer surface of Protocodium sinense (left), seen through the outer shell consisting of utricles (center, colored) and central siphons (right, colored). © Cedric Aria

Early diversification of the plant kingdom

Through an X-ray analysis of the specimen, the team was able to make a “cross section” that allowed them to visualize the internal structure of the algae. Spherical in appearance, these small fossils they do not exceed half a millimeter in width, with a size similar to large pollen grains. But above all, they have many features in common with modern algae, of the genus Code.

“Protocodium belongs to a known lineage of green algae and has a surprisingly modern architecture, showing that these algae were already well diversified before the end of the Ediacaran period”explains Cédric Aria in a releasestudy co-author and researcher at the University of Toronto.

The detailed anatomy of Protocodium sinense (from a. to e.) and comparison with the modern genus Codium (in f.),...

The detailed anatomy of Protocodium sinense (from a. to e.) and comparison with the modern genus Codium (in f.),…

> Read more about Future

Leave a Comment

Your email address will not be published. Required fields are marked *