Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ancient organisms discovered in Canadian gold mine

22.08.2007
Scientists have suspected that the three known domains of life -- eukaryotes, bacteria, and archaea -- branched off and went their separate ways around three billion years ago. But pinning down the time of that split has been an elusive task.

Now, a team of scientists present direct evidence that the three domains of life coexisted at least as long as 2.7 billion years ago.

The discovery came from chemical examination of shale samples, loaded with oily lipid remains of archaea found in a deep Canadian gold mine near Timmins, Ontario, about 400 miles north of Toronto.

Details are reported in the August 20-24 early edition of the Proceedings of the National Academy of Sciences.

Fabien Kenig, associate professor of earth and environmental sciences at the University of Illinois at Chicago, and his former doctoral student Gregory Ventura, spent nearly five years carefully analyzing the shale samples, originally to compare what they found with an earlier Australian study suggesting the presence of eukaryotes some 2.7 billion years ago.

Ventura, now a post-doctoral researcher at the Woods Hole Oceanographic Institution, said initial laboratory results stunned him. "I thought there was something very wrong, that the samples were contaminated," he said.

But Kenig was more confident they were on to something significant.

They didn't learn the true value of the material until it was analyzed using a sophisticated, multi-dimensional gas chromatography instrument at the U.S. Coast Guard Academy.

When they analyzed a sample, Kenig said, they were able to pull apart its complex mixture of molecular fossils, and found it was "essentially made of archaea-derived lipids."

The archaea lived in water and sediments when the region was covered by the sea. After burial, the archaea thrived where very hot water circulated in the rocks and where gold was deposited. Later, shale containing fossilized archaea got buried under thousands of feet of volcanic rock and sediments.

The researchers studied shale samples using a scanning electron microscope. They also analyzed rock formation, mineral deposits and molecular fossils. Findings led the researchers to conclude that archaea and the other two life domains coexisted.

"Now we are sure the three domains of life were well separated and evolving (independently) by 2.7 billion years ago," said Kenig.

The finding broadens the known geographic reach of archaea during this time period, adding proof that the ancient organisms existed both in sedimentary environments and in subsurface hydrothermal settings.

"Considering the extent and composition of today's deep biosphere, it is likely that such hydrothermal subsurface communities have existed for much of the Earth's history," Ventura and Kenig write.

Paul Francuch | EurekAlert!
Further information:
http://www.uic.edu

More articles from Earth Sciences:

nachricht Geophysicists and atmospheric scientists partner to track typhoons' seismic footprints
16.02.2018 | Princeton University

nachricht NASA finds strongest storms in weakening Tropical Cyclone Sanba
15.02.2018 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Contacting the molecular world through graphene nanoribbons

19.02.2018 | Materials Sciences

When Proteins Shake Hands

19.02.2018 | Materials Sciences

Cells communicate in a dynamic code

19.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>