Francevillian biota

The Francevillian biota (Also referred to as Gabon macrofossils, Gabonionta or Francevillian group fossils) are a collection of 2.1-billion-year-old Palaeoproterozoic macroscopic structures, controversially suggested to be fossils, known from the Francevillian B Formation in Gabon, a black shale province notable for its lack of any noticeable metamorphism. The structures have been postulated by some authors to be evidence of the earliest form of multicellular life, and of eukaryotes. They were discovered by an international team led by Moroccan geologist Abderrazak El Albani, of the University of Poitiers, France. While they have yet to be assigned to a formal taxonomic position, they have been informally and collectively referred to as the "Gabonionta", including by the Natural History Museum Vienna in 2014. The status of the structures as fossils has been questioned, and they remain a subject of debate.

Morphology

The structures are up to 17 centimetres (6.7 in) in size. They form flattened disks with a characteristic morphology, including circular and elongated specimens. A spherical to ellipsoidal central body is bounded by radial structures. The structures show three-dimensionality and purportedly coordinated growth.

A newer 2014 study by El Albani et al. describes multiple types of structures with different morphologies. There are convoluted tubes, and "string of pearls"-like structures that terminate in a "flower". This is similar to dictyostelid slime molds, amoebal organisms that form multicellular assemblies to migrate. However, the structures cannot simply be dictyostelids as dictyostelids are not marine organisms. Among known fossils, the Ediacaran Nemiana and Beltanelloides are most similar when compared to the "string of pearls".