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Fossilien-Zellen, die mehr als 3,4 Mrd. Jahre alt sein sollen, und damit in einer sauerstofffreien Welt lebten, wurden nun nach eingehenden Untersuchungen als solche festgestellt. Damit sind gleich mehrere Fachgebiete von dieser Entdeckung betroffen.

Zum einen wirft das ein Licht auf die sehr frühe Lebensentstehung auf der Erde zum anderen aber auch auf die Möglichkeit für Bakterien auf anderen Himmelskörpern, wo es keinen Sauerstoff in der Atmosphäre gibt.

science daily berichtet: hier.

Significantly, there was very little oxygen present as there were no plants or algae yet to photosynthesise and produce oxygen. The new evidence points to early life being sulfur-based, living off and metabolizing compounds containing sulfur rather than oxygen for energy and growth.

'Such bacteria are still common today. sulfur bacteria are found in smelly ditches, soil, hot springs, hydrothermal vents -- anywhere where there's little free oxygen and they can live off organic matter,' explains Professor Brasier.

The microfossils were found in a remote part of Western Australia called Strelley Pool. They are very well preserved between the quartz sand grains of the oldest beach or shoreline known on Earth, in some of the oldest sedimentary rocks that can be found anywhere.

'We can be very sure about the age as the rocks were formed between two volcanic successions that narrow the possible age down to a few tens of millions of years,' says Professor Brasier. 'That's very accurate indeed when the rocks are 3.4 billion years old.'

The microfossils satisfy three crucial tests that the forms seen in the rocks are biological and have not occurred through some mineralization process.

The fossils are very clearly preserved showing precise cell-like structures all of a similar size. They look like well known but much newer microfossils from 2 billion years ago, and are not odd or strained in shape.

The fossils suggest biological-like behavior. The cells are clustered in groups, are only present in appropriate habitats and are found attached to sand grains.

And crucially, they show biological metabolisms. The chemical make-up of the tiny fossilized structures is right, and crystals of pyrite (fool's gold) associated with the microfossils are very likely to be by-products of the sulfur metabolism of these ancient cells and bacteria.

Etwa zwei Tage vor ihrem Erscheinen können nun Sonnenflecken mit Hilfe von Schallwellen-Anomalien an der Oberfläche vorhergesagt werden, wie astronews.com berichtet: hier.