ArticleProceedings of the National Academy of Sciences of the United States of America2021
Petrographic carbon in ancient sediments constrains Proterozoic Era atmospheric oxygen levels.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
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12 citing papers in PubMed.
- Noncanonical genetic markers resolve the pre-GOE emergence of aerobic bacteria in Earth's history.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Oxygen regulation in the earliest animals: spatiotemporal resolution of oxygen dynamics in single-osculumFrontiers in physiology · 2026Article
- Breathing life into the boring billion: Direct constraints from 1.4 Ga fluid inclusions reveal a fair climate and oxygenated atmosphere.Proceedings of the National Academy of Sciences of the United States of America · 2025Article
- An expansive global oxygenation of Earth's surface environments 1.4 billion years ago.Nature communications · 2025Article
- Atmospheric oxygen and methane on the early Earth.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- A reassessment of the "hard-steps" model for the evolution of intelligent life.Science advances · 2025Review
- Constraining the oxygen requirements for modern microbial eukaryote diversity.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Respiration kinetics and allometric scaling in the demosponge Halichondria panicea.BMC ecology and evolution · 2023Article
- Strong evidence for a weakly oxygenated ocean-atmosphere system during the Proterozoic.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- An overview of experimental simulations of microbial activity in early Earth.Frontiers in microbiology · 2022Review
- Article
- Individual Microfossil δGeobiologyArticle
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Authors and funding
7 authors.
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No grant is acknowledged in the PubMed record.
Abstract
Oxygen concentration defines the chemical structure of Earth's ecosystems while it also fuels the metabolism of aerobic organisms. As different aerobes have different oxygen requirements, the evolution of oxygen levels through time has likely impacted both environmental chemistry and the history of life. Understanding the relationship between atmospheric oxygen levels, the chemical environment, and life, however, is hampered by uncertainties in the history of oxygen levels. We report over 5,700 Raman analyses of organic matter from nine geological formations spanning in time from 742 to 1,729 Ma. We find that organic matter was effectively oxidized during weathering and little was recycled into marine sediments. Indeed, during this time interval, organic matter was as efficiently oxidized during weathering as it is now. From these observations, we constrain minimum atmospheric oxygen levels to between 2 to 24% of present levels from the late Paleoproterozoic Era into the Neoproterozoic Era. Indeed, our results reveal that eukaryote evolution, including early animal evolution, was not likely hindered by oxygen through this time interval. Our results also show that due to efficient organic recycling during weathering, carbon cycle dynamics can be assessed directly from the sediment carbon record.
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