origins-of-life

Physics & Space

Earth History & Geology

• Earliest Life: Fossils, Inference and the Road to OxygenThe oldest surviving evidence of life supplies a minimum antiquity, not a birthday. If a convincing fossil is 3.48 billion years old, life was present by then; it may have begun much earlier. Nor does finding life in one habitat prove that life originated there.
• Early Earth: What the Rocks Actually Tell UsA wet planet is not yet a living planet. Before asking how life began, ask a narrower question: what environments were actually available, and how do we know? This is where origin-of-life research meets geology rather than a cinematic reconstruction of a steaming ocean.
• Prebiotic Chemistry: Ingredients Are Not Yet a SystemLife uses carbon compounds, but “organic” does not mean “made by an organism.” The deeper problem is how nonliving chemistry could repeatedly make useful products faster than dilution, decomposition and side reactions removed them.
• Protocells, Metabolism and Competing Origin HypothesesA catalyst dispersed in an ocean may help every nearby competitor. A useful reaction inside a compartment can preferentially help the compartment containing it. A boundary changes who benefits from chemistry, making it a potential bridge from molecular reactions to reproducing lineages.
• RNA and the Problem of Making CopiesA sequence can store information without being able to reproduce it. RNA is interesting because it can potentially join two roles that modern cells distribute among different molecules: a sequence that can be copied and a folded structure that can catalyze chemistry.