https://en.wikipedia.org/wiki/Boring_Billion
The Boring Billion, otherwise known as the Barren Billion, the Dullest Time in Earth's History, and Earth's Middle Ages, is the time period between 1.8 and 0.8 billion years ago (Gya) spanning the middle Proterozoic eon, characterized by more or less tectonic stability, climatic stasis, and stalled biological evolution. It is bordered by two different oxygenation and glacial events, but the Boring Billion itself had very low oxygen levels and no evidence of glaciation.
