Oxygen levels in the atmosphere during the mid-Proterozoic—about 1.4 billion years ago—were higher than previously thought, according to an international team of researchers who looked at oxygen ...

A study suggests that around 1 billion years ago, photosynthetic primary producers were likely too small to support the development of animal ecosystems. Approximately between 1.8 and 0.8 billion ...

The Proterozoic is a Precambrian eon of geologic time extending from about 2.5 billion to 541 million years ago, bounded by the Archean–Proterozoic and Proterozoic–Phanerozoic transitions. It is ...

The Proterozoic Eon, spanning from 2,500 million to 539 million years ago, marked a transformative chapter in Earth's history ...

"This project grew from a Pardee keynote symposium ('Neoproterozoic geobiology : fossils, clocks, isotopes, and rocks') held at the 2003 Geological Society of America annual meeting in Seattle"--Pref.