Multicellular origin at 2.1 billion years ago

New fossils found in Gabon might push back the origin of multicellular life. By about 200 million years.

Here we report the discovery of centimetre-sized structures from the 2.1-Gyr-old black shales of the Palaeoproterozoic Francevillian B Formation in Gabon, which we interpret as highly organized and spatially discrete populations of colonial organisms.

Macrofossils in colony form from the FB2 level. Scale bars, 1.0 cm.

The authors deduce that these long structures (up to 12 cm) aren't just colonies of bacteria, but must have had cell-to cell signalling and coordinated-growth behaviour.

Although we cannot determine the precise nature and affinities of the 2.1-Gyr macroorganisms from the Francevillian B Formation of Gabon, we interpret these fossils as ancient representatives of multicellular life, which expanded so rapidly 1.5 Gyr later.

I'm not at all educated to have an opinion here... They look convincing enough like fossils, but if experts were to tell me that these structures could have been formed by non-organic processes, I'd have to believe them. On the other hand, while this is definitely a story that is deservedly on the cover of Nature, moving the origin of metazoans multicellular life back 200 million years isn't something that is going to shake up a lot of people who aren't just working in that narrow field already.


Evidence of early life, and the chemical state of the atmosphere and oceans, from News & Views article in Nature by Donoghue ∓ Antcliffe, Early life: Origins of multicellularity. The Gabon fossils would push back the first occurrence of metazoans multicellularity 200 million years (red bar), but, interestingly, close to the oldest certain bacterial fossils.





Four different specimens in four different views. a, Original specimen. b, Volume rendering in semi-transparency. c, Transverse (axial) two-dimensional section. d, Longitudinal section running close to the estimated central part of the specimen. Scale bars, 5 mm.

Reference:
Albani, A., Bengtson, S., Canfield, D., Bekker, A., Macchiarelli, R., Mazurier, A., Hammarlund, E., Boulvais, P., Dupuy, J., Fontaine, C., Fürsich, F., Gauthier-Lafaye, F., Janvier, P., Javaux, E., Ossa, F., Pierson-Wickmann, A., Riboulleau, A., Sardini, P., Vachard, D., Whitehouse, M., & Meunier, A. (2010). Large colonial organisms with coordinated growth in oxygenated environments 2.1 Gyr ago Nature, 466 (7302), 100-104 DOI: 10.1038/nature09166

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Update 7/8:
I have changed all instances of 'metazoan' with 'multicellular', also in the title. My mistake. Thanks to Psi Wavefunction for pointing that out.