Morphological record of oxygenic photosynthesisin conical stromatolites
Bosak T, Liang B, Sim MS, Petroff AP. 2009. Morphological record of oxygenic photosynthesisin conical stromatolites. Proceedings of the National Academy of Sciences of the United States of America (PNAS). 106(27):10939-10943
Conical stromatolites are thought to be robust indicators of thepresence of photosynthetic and phototactic microbes in aquaticenvironments as early as 3.5 billion years ago. However, phototaxisalone cannot explain the ubiquity of disrupted, curled, andcontorted laminae in the crests of many Mesoproterozoic, Paleoproterozoic,and some Archean conical stromatolites. Here, wedemonstrate that cyanobacterial production of oxygen in the tipsof modern conical aggregates creates contorted laminae and submillimeter-to-millimeter-scale enmeshed bubbles. Similarly sizedfossil bubbles and contorted laminae may be present only in thecrestal zones of some conical stromatolites 2.7 billion years old oryounger. This implies not only that cyanobacteria built Proterozoicconical stromatolites but also that fossil bubbles may constrain thetiming of the evolution of oxygenic photosynthesis.
- Type
- Journal Article
- Authors
- Bosak, Tanja; Liang, Biqing; Sim, Min; Petroff, Alexander
- Units
- GRYN
- Keywords
- Cyanobacteria, microbialite