Cells preserved whole
Actual microbial cells, not just chemical traces, survive in 3.4-billion-year-old sandstone.
- When
- Known to
- ± 30 million years
- Era
- Paleoarchean, Archean
Microstructures in Western Australian rocks show cell walls, division stages and clustering, with sulfur isotopes and mineral associations indicating sulfur-metabolising bacteria. They lived on a beach in an oxygen-free world, using sulfur where later organisms would use oxygen. It is among the earliest evidence of preserved cells rather than the chemistry they left behind.