Archean organic microfossils bear witness to the presence of life on Earth from 3.5 billion years ago. These generally have simple morphologies – spheroids, filaments, lenticles – which does not allow their biological nature to be precisely evaluated. Our perception of primitive therefore remains rather fragmented.
Organic microfossils with morphological features that may indicate active motility as early as 3.4 billion years ago were recently discovered by scientists from the METIS and IMPMC laboratories. Chemically isolated from a rock from the Strelley Pool formation (Australia), these microfossils were imaged by . Their geochemical composition was then characterized by Raman spectroscopy, NanoSIMS and .
Beyond a geochemical composition attesting to their Archean origin and their biological nature, some of the fossil specimens studied present a unique morphological feature: a “tail”. This is subdivided into several parts and presents morphometric criteria comparable to those measured on the locomotive organelles of current microorganisms. Less than one years after the had become habitable, certain microorganisms were perhaps already able to direct their movements. This discovery changes our perception of primitive biodiversity.
Find out more:
Microfossils with tail-like structures in the 3.4 Gyr old Strelley Pool Formation – Precambrian Research, 358 (2021)
Frédéric Delarue, Sylvain Bernard, Kenichiro Sugitani, François Robert, Romain Tartèse, Sonja-Verena Albers, Rémi Duhamel, Sylvain and Sylvie Derenne.
Frédéric Delarue – Environmental Media, Transfers and Interactions in Hydrosystems and Soils (METIS) – frederic.delarue at upmc.fr