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heute. Erste Prokariota ( ca. 4.0 Ma). Zeit. RNA -Welt ?. chemische Evolution. Bildung von Erde und Mond (ca. 4.5 Ma). A possible “RNA world” scenario. Abiotic production of biomolecules (Miller-Urey). Vier (5) stickstoffhaltige Nukleo -Basen.
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heute Erste Prokariota (ca. 4.0 Ma) Zeit RNA-Welt ? chemische Evolution Bildung von Erde und Mond (ca. 4.5 Ma)
Abiotic production of biomolecules (Miller-Urey)
Vier (5) stickstoffhaltige Nukleo-Basen Bausteine von DNA und RNA: Nukleotide
Proterozoic: 2500 Ma – 542 Ma Acritarchs are small organic fossils, present from approximately 3,200 million years ago to the present. Their diversity reflects major ecological events such as the appearance of predation and the Cambrian explosion.
Phanerozoic Eon: 542 Ma – present The Phanerozoic Eon, literally the "period of well-displayed life", marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, which are divided by major mass extinctions.
The ability of cyanobacteria to perform oxygenic photosynthesis is thought to have converted the early reducing atmosphere into an oxidizing one, which dramatically changed the composition of life forms on Earth by stimulating biodiversity and leading to the near-extinction of oxygen-intolerant organisms. According to endosymbiotic theory, chloroplasts in plants and eukaryotic algae have evolved from cyanobacterial ancestors via endosymbiosis.
Colourful thermophilic archaebacteria stain in Midway Geysir Basin