Architects of the earliest microfossils, atmospheric oxygen, and plastids.

Fossilized cyanobacteria

The cyanobacteria were not the first cells to evolve on the planet - those were probably heterotrophic prokaryotes. However, the "self-fossilizing" activity of mats of cyanobacterial prokaryotes has left us with the oldest fossils yet found.

3.5 Ga stromatolite cyanobacterial fossils and compare with Anabaena or Hapalosiphon filament

Found within oil bubbles in quartz dated at about 1000 million (1 billion) years: remnants cell walls of cyanobacteria trapped in oil bubbles, 1 Ga

Fossilized cyanobacterial endoliths: Eohyella dichotemata of Late Protetozoic and Eohyella fossil assemblage or Eohyella campbellii ~ at 1.5 Ga, the oldest known microbial endolith compare with Hyella stella ~ similar to Eohella dichotemata of Late Proterozoic /

Compare Precambrian cyanobacterial colony in stromatolic carbonaceous chert, NWT, 2 Ga with Cyanobacterial cocci or Cocci of cyanobacteria or Coccal cyanobacteria or Entophysalis granulosa or Pleurocapsa sp. or Synechoccus

Compare cyanococci Bitter Springs chert with Chroococcus

Compare a modern cyanobacteria
with fossil thin-section of colonial chroococchalean cyanobacterium, Bitter Springs chert, Late Proterozoic

Compare a modern Lyngba sp.
with fossil thin-section of filamentous Palaeolyngbya, Bitter Springs chert, Late Proterozoic

View comparison photomicrographs and thin sections in comparison of fossil and modern cyanobacteria.

"The earliest microscopicallyrecognisable microfossils were reported from the 3.49 Ga Dresser Formation and from the 3.46 Ga Apex Chert of the Pilbara craton, Australia. Although their biogenecity has recently been questioned, whole rock carbon isotopic compositions with RuBisCO-signatures and morphological affinity of microfossils to recent cyanobacteria and bacteria, together with laser Raman identification of carbon within the fossil bodies, testify to their authenticity." Read article that examines criteria for concluding that fossilized structures are of biological origin:
Archean microfossils: a reappraisal of early life on Earth by Wladyslaw Altermann, Józef Kazmierczak.
Altermann W, Kazmierczak J. Archean microfossils: a reappraisal of early life on Earth. Res Microbiol. 2003 Nov;154(9):611-7.

Abstract: "The oldest fossils found thus far on Earth are c. 3.49- and 3.46-billion-year-old filamentous and coccoidal microbial remains in rocks of the Pilbara craton, Western Australia, and c. 3.4-billion-year-old rocks from the Barberton region, South Africa. Their biogenicity was recently questioned and they were reinterpreted as contaminants, mineral artefacts or inorganic carbon aggregates. Morphological, geochemical and isotopic data imply, however, that life was relatively widespread and advanced in the Archean, between 3.5 and 2.5 billion years ago, with metabolic pathways analogous to those of recent prokaryotic organisms, including cyanobacteria, and probably even eukaryotes at the terminal Archean." By authors: Publikationen


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