Replicating the Origin of Life on Earth: The Importance of Hydrothermal Microenvironments

The “primordial soup” is a widely accepted theory of the origin of life on Earth. However, this theory fails to explain how simple molecules (e.g., amino acids and sugars), diluted in prebiotic oceans, could have reached high concentrations necessary to synthesize more complex molecules, the building blocks of life (e.g., proteins and DNA). Since the discovery of the first hydrothermal vents in the deep ocean floor and their ability to provide a favorable environment for life, hydrothermal systems have emerged as an alternative to the “soup” theory. In particular, porous mineral formations near hydrothermal vents, subjected to thermal gradients from the cold deep-sea water and the hot magma underneath, could have provided microenvironments that enabled the first forms of life. In our project, we replicated the conditions for the origin of life in a laboratory scale to understand how hydrothermal microenvironments could produce high concentrations of molecules necessary to form life’s building blocks. Specifically, we constructed pore-like chambers inside which convective flow can be established in a controlled way. Using this approach, we studied different possible flow trajectories that could occur inside such pores, ranging from well-organized patterns to highly disorganized or chaotic flows. The results showed that chaotic flow can quickly accumulate molecules in certain regions of the pore-like chambers, providing the necessary high concentrations for the synthesis of life’s building blocks to occur. This study provides evidence for hydrothermal vents as enablers of the first forms of life in Earth’s primitive oceans. Our most recent research focuses on an interesting phenomenon observed in these hydrothermal microenvironments. Two immiscible liquids inside these microenvironments form complex microstructures in a consistent and reproducible fashion due to the presence of convective flow. We are currently investigating properties of these microstructures, potential for encapsulating different liquids and species, other geometries of the pore-like chambers that could lead to their formation, and their possible applications.