Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Evidence of 3.5 billion-year-old bacterial ecosystems found in Australia

13.11.2013
Reconstructing the rise of life during the period of Earth's history when it first evolved is challenging.

Earth's oldest sedimentary rocks are not only rare, but also almost always altered by hydrothermal and tectonic activity.


A rock surface is displaying "polygonal oscillation cracks" in the 3.48 billion years old Dresser Formation, Pilbara region, Western Australia. Such and similar sedimentary structures are of biological origin. They document ancient microorganisms that formed carpet-like microbial mats on the former sediment surface. The Dresser Formation records an ancient playa-like setting -- similar environments are occurring on Mars as well. The MISS constitute a novel approach to detect and to understand Earth's earliest life.

Credit: Nora Noffke

A new study from a team including Carnegie's Nora Noffke, a visiting investigator, and Robert Hazen revealed the well-preserved remnants of a complex ecosystem in a nearly 3.5 billion-year-old sedimentary rock sequence in Australia. Their work is published in Astrobiology.

The Pilbara district of Western Australia constitutes one of the famous geological regions that allow insight into the early evolution of life. Mound-like deposits created by ancient photosynthetic bacteria, called stromatolites, and microfossils of bacteria have been described by scientists in detail. However, a phenomenon called microbially induced sedimentary structures, or MISS, had not previously been seen in this region. These structures are formed from mats of microbial material, much like mats seen today on stagnant waters or in coastal flats.

The team included Noffke, Hazen, Daniel Christian of Old Dominion University, and David Wacey of the University of Western Australia. They described various MISS preserved in the region's Dresser Formation. Advanced chemical analyses point toward a biological origin of the material.

The Dresser MISS fossils resemble strongly in form and preservation the MISS from several other younger rock samples, such as a 2.9 billion-year-old ecosystem Noffke and her colleagues found in South Africa.

"This work extends the geological record of MISS by almost 300 million years," said Noffke, who is also a professor at ODU. "Complex mat-forming microbial communities likely existed almost 3.5 billion years ago."

The team proposes that the sedimentary structures arose from the interactions of bacterial films with shoreline sediments from the region.

"The structures give a very clear signal on what the ancient conditions were, and what the bacteria composing the biofilms were able to do," Noffke said.

MISS are among the targets of Mars rovers, which search for similar formations on that planet's surface. Thus, the team's findings could have relevance for studies of our larger Solar System as well.

This work was supported by the NSF Paleobiology and Sedimentary Geology program, NASA Astrobiology Institute, NASA Exobiology and Evolutionary Biology Programs, and the Deep Carbon Observatory and the Carnegie Institution for Science.

The Carnegie Institution for Science is a private, nonprofit organization headquartered in Washington, D.C., with six research departments throughout the U.S. Since its founding in 1902, the Carnegie Institution has been a pioneering force in basic scientific research. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.

Old Dominion University is a forward-focused public, research university with its main campus in Norfolk, Va. Research specialties of the university's College of Sciences include those in geobiology, geochemistry, geophysics and oceanography.

Robert M. Hazen | EurekAlert!
Further information:
http://www.ciw.edu

More articles from Earth Sciences:

nachricht The Wadden Sea and the Elbe Studied with Zeppelin, Drones and Research Ships
19.09.2017 | Helmholtz-Zentrum Geesthacht - Zentrum für Material- und Küstenforschung

nachricht FotoQuest GO: Citizen science campaign targets land-use change in Austria
19.09.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>