A group of scientists from Australia and England have discovered what could be the oldest known record of life on Earth. The new micro-fossils, traces of ancient single-celled organisms, were discovered in 3.4 billion year old sandstone in Western Australia. The study appears in the publication Nature Geoscience. If the research stands up to scrutiny, it could make them the oldest known fossils of life on Earth. This wouldn't set well with another team of scientists who have been making the same claim, although the validity of their find has been questioned.

SOURCE
New York Times story