January 2, 2013
Researchers have found fossils of bacteria that are nearly 3.5 billion years old, believed to be the oldest visible fossils ever uncovered.
The fossils, found in northwest Australia’s Pilbara region, are from a time before oxygen existed on Earth and are from just one billion years after Earth’s formation, according to Old Dominion University’s Nora Noffke, one of the researchers who worked on the project.
The fossils are imprints found on sandstone that was formed when microbes interacted with rock sediment. Scientists have discovered older rocks, but Noffke says those rocks have eroded to the point where traces of life are all but impossible to find.