The scientists say this part of Canada likely once formed part of an iron-rich deep-sea hydrothermal vent system, which provided a habitat for some of Earth’s first life forms, between 3,770 and 4,300 million years ago. In a find that is certain to spark debate among experts, a team of Canadian and international researchers has determined that tiny filament-like structures found in rock samples from an ancient outcrop are the mineral remains of bacteria that lived more than 3.77 billion years ago. “The most exciting thing about this discovery is that we know life managed to get a grip and start on Earth at such an early time in Earth’s evolution, which gives us exciting questions as to whether we are alone in the solar system or in the universe,” said PhD student Matthew Dodd from University College London (UCL), who is the first author on a new paper about the finding in the journal Nature. “This speedy appearance of life on Earth fits with other evidence of recently discovered 3,700 million year old sedimentary mounds that were shaped by microorganisms.”

Prior to this discovery, the oldest microfossils reported were found in Western Australia and were dated at 3.4 billion years old, leading scientists to speculate that life probably started around 3.7 billion years ago.
Scientists announce the finding of microfossils up to almost 4.3 billion years old, within rocks from the Hudson Bay shoreline in northern Quebec, Canada, that may represent the oldest-known evidence of life on Earth.