Fossil mimics may be more common in ancient rocks than actual fossils

This latest research suggests we can actually not be sure when life first emerged on earth!

"The Precambrian rock record contains numerous examples of microscopic organic filaments and spheres, commonly interpreted as fossil microorganisms. Microfossils are among the oldest traces of life on Earth, making their correct identification crucial to our understanding of early evolution. Yet, spherical and filamentous microscopic objects composed of organic carbon and sulfur can form in the abiogenic reaction of sulfide with organic compounds. Termed organic biomorphs, these objects form under geochemical conditions relevant to the sulfidic environments of early Earth. Furthermore, they adopt a diversity of morphologies that closely mimic a number of microfossil examples from the Precambrian record. ..."

Fossil mimics may be more common in ancient rocks than actual fossils | Science News Abiotic objects that resemble microbes are much hardier than their biological brethren

Here is the underlying research paper:

Organic biomorphs may be better preserved than microorganisms in early Earth sediments (open access)

"Sphere-shaped “biomorphs” — crystalline objects made abiotically through chemical reactions — can closely resemble microfossils. Such biomorphs are more likely to be preserved in rocks than fossils of microorganisms, researchers say."