The researchers show the most primitive form of aerobic respiring life on land came into existence 2.48 billion years ago.
The research team, led by U of A geomicrobiologist Kurt Konhauser made their find by investigating a link between atmospheric oxygen levels and rising concentrations of chromium in the rock of ancient sea beds. The researchers suggest that the jump in chromium levels was triggered by the land-based oxidization of the mineral pyrite.
Pyrite oxidation is driven by bacteria and oxygen. Aerobic bacteria broke down the pyrite, which released acid at an unprecedented scale. The acid then dissolved rocks and soils into a cocktail of metals, including chromium, which was transferred to the ocean by the runoff of rain water.
Konhauser says the key to the process is oxygen in Earth's atmosphere that allowed bacterial oxidation of pyrite. The researchers dated the peak for chromium levels in marine sedimentary rock was reached 2.48 billion years ago.
"This gives us a new date for the Great Oxidation Event, the time when the atmosphere first had oxygen," said Konhauser. "The rising levels of atmospheric oxygen fostered the evolution of new bacteria species that survived by aerobic respiration on land.
"Our ancestors started off in an acid bath as oxygen-breathing bacteria."
The same bacterial life forms are alive and well today, living off pyrite and settling in the highly acidic waste waters of mining sites the world over.
The research by Konhauser and his team is published in the Oct.19 edition of the journal Nature.
Brian Murphy | EurekAlert!
Nanotubes built from protein crystals: Breakthrough in biomolecular engineering
15.11.2018 | Tokyo Institute of Technology
Insect Antibiotic Provides New Way to Eliminate Bacteria
15.11.2018 | Universität Zürich
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
15.11.2018 | Earth Sciences
15.11.2018 | Physics and Astronomy
15.11.2018 | Physics and Astronomy