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!
Receding glaciers in Bolivia leave communities at risk
20.10.2016 | European Geosciences Union
UM researchers study vast carbon residue of ocean life
19.10.2016 | University of Miami Rosenstiel School of Marine & Atmospheric Science
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences