Setting the geological scene for the origin of life and continuing open questions about its emergence

24 January 2023 par Isabelle Frapart
Life emerged on a planet Earth, whose environmental conditions were very different to those of the Earth today. In this context, our paper describes the basic ingredients that existed on the early Earth as a recipe for prebiotic chemists. We also evoke the open questions concerning the origin of life.

The origin of life is one of the most fundamental questions of humanity. It has been and is still being addressed by a wide range of researchers from different fields, with different approaches and ideas as to how it came about. However, what is missing from the prebiotic chemical experiments is precise information about the environment and the conditions reigning on the early Earth during the Hadean Era (4.5-4.0 Ga). In particular, there is a lack of understanding about the inorganic ingredients that were available, the stability and longevity of the various environments suggested as locations for the emergence of life, as well the kinetics and rates of the prebiotic steps leading to life.

This contribution reviews our current understanding of the geology of the early Earth at the time when life emerged. Having set the geological scenario, we evoke the still open questions about the origin of life: did life start organically or in mineralogical form? If organically, what was the origin of the organic constituents of life? What came first, metabolism or replication? What was the time-scale for the emergence of life? We conclude that the way forward for prebiotic chemistry is an approach merging geology and chemistry, i.e., far-from-equilibrium cycling of organic reactions occurring repeatedly and iteratively at mineral surfaces under hydrothermal-like conditions.

Setting the geological scene for the origin of life and continuing open questions about its emergence
Frances Westall1, André Brack, Alberto G. Fairén and Mitchell D. Schulte
Frontiers in Astronomy and Space Sciences - 05 January 2023 - Volume 9 - doi : 10.3389/fspas.2022.1095701 9:1095701

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