Benthic perspective on Earth’s oldest evidence for oxygenic photosynthesis
Open accessAbstract
Significance: The history of oxygen at Earth’s surface is intimately tied to its production by oxygenic photosynthesis, whereby plants, algae, and cyanobacteria release O 2 as a waste product. Despite this metabolism’s profound importance, its evolutionary timing is poorly understood. Studies have increasingly revealed a temporal disconnect between evidence for the presence of O 2 during weathering as early as 3.0 billion years ago and its atmospheric accumulation 500 million years later. We review this problem and numerically demonstrate that local O 2 production and immediate consumption in surface-bound (benthic) microbial ecosystems at profound disequilibrium conditions is the most parsimonious explanation for this delay. Thus, emergence of continental landmass was likely a crucial factor in the earliest oxygenation of Earth’s surface environment.
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Oxygen oases of cyanobacteria within soils or lakebeds may have mobilized Mo, Se, Re, U, and N into rivers and then the sea.
“Alternatively, oxygen oases of cyanobacteria within soils or lakebeds may have mobilized these elements into rivers and then the sea (117).”
From The Archean atmosphere (2020) · cites this paper as [117]
The paper’s Fig. 3 discussion describes localized oxygen production and oxidative weathering by continental benthic communities, and the adjacent discussion says weathering products may travel over catchment scales to marine basins. It specifically discusses Mo and Re sourcing and U remobilization, and mentions nitrate as an oxidation product. Our copy does not establish Se mobilization, so it does not support the full list of elements attributed to the paper (section “A B” and “Significance”; page numbers unavailable). (LLM, conf=0.84)
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- Authors
- Lalonde, S. V., & Konhauser, K. O.
- Affiliations
- Centre National de la Recherche Scientifique (FR)
- University of Alberta (CA)
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 2015-01-12
- Volume
- 112
- Issue
- 4
- Pages
- 995-1000
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC4313849
- OpenAlex
- W2056482280
- Cited by
- 224
- References
- 68
- Citations by year
- 2026: 8 · 2025: 23 · 2024: 21 · 2023: 12 · 2022: 17 · 2021: 26 · 2020: 20 · 2019: 25 · 2018: 21 · 2017: 20 · 2016: 17 · 2015: 13
- FWCI
- 17.89
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion)
- Europe PMC (PubMed Central) (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- HAL (submittedVersion, other-oa)
- Funders
- Agence Nationale de la Recherche (ANR-10-LABX-0019)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
- Physical Sciences › Earth and Planetary Sciences › Geochemistry and Petrology › Geochemistry and Elemental Analysis
- Physical Sciences › Earth and Planetary Sciences › Geophysics › Geological and Geochemical Analysis
- Keywords
- Great Oxidation Event, oxygenic photosynthesis, oxidative weathering, benthic environment, biological soil crusts, microbial mats, cyanobacteria, atmospheric oxygenation, Archean, redox imbalance, trace metal mobilization, sulfur cycling
- MeSH terms
- Fossils, Oxygen, Photosynthesis, Earth, Planet
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