The atmosphere of the Archean eon—one-third of Earth's history—is important for
understanding the evolution of our planet and Earth-like exoplanets. New geological proxies …

Photosystem II is the water-oxidizing and O2-evolving enzyme of photosynthesis. How and
when this remarkable enzyme arose are fundamental questions in the history of life that …

Iron formations (IF) represent an iron-rich rock type that typifies many Archaean and
Proterozoic supracrustal successions and are chemical archives of Precambrian seawater …

Abstract The Archean era (4 to 2.5 billion years ago, Ga) yielded rocks that include the
oldest conclusive traces of life as well as many controversial occurrences. Carbonaceous …

Oxygenic photosynthesis is arguably the most important biological innovation in Earth's
history, facilitating the transition to a habitable planet for complex life. Dating the emergence …

The colonization of emergent continental landmass by microbial life was an evolutionary
step of paramount importance in Earth history. Here we report direct fossil evidence for life …

The record of the coevolution of oxygenic phototrophs and the environment is preserved in
three forms: genomes of modern organisms, diverse geochemical signals of surface …

Microfossils, stromatolites, preserved lipids and biologically informative isotopic ratios
provide a substantial record of bacterial diversity and biogeochemical cycles in Proterozoic …

The recognition of past habitable environments on Mars has increased the urgency to
understand biosignature preservation in and characterize analogues of these environments …

Life on Earth has existed for at least 3.5 billion years. Yet, relatively little is known of its
evolution during the first two billion years, due to the scarceness and generally poor …