Until Now
BiologyGeology

The disputed Isua stromatolites

Ridged structures in Greenland were announced as the world's oldest fossils — and may just be folded rock.

When
Known to
± 40 million years
Era
Eoarchean, Archean

In 2016 centimetre-scale layered cones at Isua were reported as stromatolites, mats built by microbial communities, which would push visible evidence of life to 3.7 billion years. A detailed reappraisal found the structures align with regional fold axes and preserve no primary sedimentary texture, arguing they are tectonic rather than biological. The original authors maintain that primary bedding survives in fold hinges. The dispute is unresolved and worth recording as such.

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