Early origins of life on Earth

PUBLICATION — Oleg Abramov, Anna Medvegy, Barbara Kremer & Stephen J. Mojzsis  2026. A Hadean timeline for the emergence of the RNA World, Nature Communications, 17, 9790. https://doi.org/10.1038/s41467-026-76978-3

Figure: Thermal model of the Earth's surface. Left, ca. 4.49 billion years ago, the heavily bombarded and heated surface of our planet is visible; right, ca. 4.3 billion years ago: high temperatures below the surface (red) and cool temperatures on the surface (brown).

Before DNA became central to life, it is thought that RNA molecules may have stored genetic information and replicated themselves. This period is called the RNA world. Computer modelling of Earth’s surface temperature indicates that around 4.33 billion years ago conditions began to mitigate, and energy-rich hydrothermal environments became increasingly common. This period may therefore have been a kind of “sweet spot”—when the conditions for the sustained occurrence of RNA-related chemistry were most favourable. However, it is emphasised that the model only allows for the assessment of Earth’s temperature and cannot directly determine when life actually emerged.