The remains of the world’s oldest meal provide more information about the most ancient animal ancestors

The researchers analyzed ancient fossils that contained preserved phytosterol molecules, the remains of their last meal. Plant sterols or plant sterols are substances found in the cell membranes of certain plants. They can be considered analogs of zoosterols, animal sterols, of which the best known is cholesterol.

By examining the particles, the scientists were able to confirm that the snail-like organism, is Kimberla Said, it has a mouth and an intestinal tract and it digests its food in the same way that modern animals do. The researchers say so Kimberla It was probably one of the most highly evolved organisms among the Ediacara fauna. With its mouth, the creature scraped algae and bacteria from the sea floor.

The ANU team found that another animal, which can reach 1.4 meters in length and has a ribbed surface, was less complex and had no eyes, mouth or digestive system. Instead, the strange creature absorbed it Dickinsonia He called out food through his body as it moved across the ocean floor.

“Our findings indicate that the Ediacara biofauna, which lived on Earth before the Cambrian explosion of modern animal life, was a mixture of absolute rarities such as Dickinsonia And more advanced animals like KimberlaOrganisms are life forms from a particular area or, as in this case, from a particular period, said lead author Dr. Ilya Bobrovsky. Bobrovsky conducted the new study as part of his PhD at ANU and now works at GeoForschungsZentrum GFZ in Potsdam.