A multinational research team has discovered ancient protosteroids in rocks dating back 1.6 billion years, suggesting that complex life existed much earlier than previously thought. These primordial molecules, key to understanding eukaryotic evolution, extend the fossil steroid record and reflect an earlier stage of eukaryotic complexity. Eukaryotes, differentiated from bacteria by their complex cell structure, include all animals, plants, and algae. The study highlights the importance of protosteroids in tracing the ancestral lineage from which modern eukaryotes, including humans, descended.
Research conducted at the Geobiomolecular Imaging Laboratory utilized advanced imaging techniques to analyze rock samples, uncovering an abundance of these ancient molecules. This discovery provides a glimpse into a time when primitive eukaryotic life thrived alongside modern eukaryotic representatives. The transition known as the “Tonian Transformation,” marked by an increase in Earth’s oxygen levels and subsequent glaciation events, played a crucial role in the evolution of these organisms. The findings not only reconcile geological and lipid fossil records but also enhance our understanding of the early conditions for the emergence of complex life, compelling ongoing research into our ancient ancestors.
