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!
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences