Francevillian Basin, Gabon

Assembled from 15 blocks · 1 evidence · 7 related

1. Story
2. A Palaeoproterozoic sedimentary basin in southeastern Gabon containing black shales about 2.1 billion years old, in which a 2010 paper reported centimetre-scale pyritised structures with regular, lobed outlines and radial fabric, interpreted as colonial organisms showing coordinated growth. If the interpretation holds, it pushes macroscopic, possibly multicellular life back by more than a billion years relative to the next accepted examples, and places it immediately after the Great Oxidation Event and the Lomagundi carbon-isotope excursion — an oxygen pulse that would plausibly permit larger bodies. The interpretation is genuinely contested. Sceptics argue the structures are abiotic pyrite growths or sedimentary concretions, and note that nothing comparable appears anywhere in the following billion years, which would require a very long ghost lineage or an origin that failed. The Francevillian is the clearest case in this Journey of a claim whose significance depends entirely on whether a shape is biological.
3. Knowledge
4. The evolution of multicellularity
5. Francevillian Basin, Gabon
6. Connections
7. The evolution of multicellularity
8. Centimetre-scale structures reported from 2.1 Ga Gabonese shales
9. Endosymbiosis and the eukaryotic cell
10. Bangiomorpha pubescens
11. Francevillian Basin, Gabon
12. Ediacara Hills, Flinders Ranges
13. Centimetre-scale structures reported from 2.1 Ga Gabonese shales
14. Evidence
15. Supports the description of the Francevillian structures and their interpretation as colonial organisms. The interpretation is disputed; no rebuttal is cited here. V55 verification basis: this session had no network access to any source — WebFetch was egress-blocked and the WebSearch budget was exhausted — so the cited work was not retrieved and its pagination was not re-checked. Volume and page range are quoted from standing knowledge and were not re-checked.