Researchers have found evidence of ancient microorganisms that lived in what is now Western Australia at least 4.1 billion years ago. If confirmed, the discovery suggests that life originated on Earth 300 million years earlier than previously thought. ...
The ancient microorganisms in question were found trapped inside zircons formed from magma in Western Australia. Zircons are heavy, durable minerals that can capture and preserve traces of their immediate environment, just like tiny time capsules.
Harrison and his team analysed more than 10,000 of these zircons, dating back 4.1 billion years, and found some that contained mysterious dark specks. Upon closer inspection, they discovered that these specks had the molecular and chemical structure of ancient microorganisms.
But to confirm that they'd found life, they needed to find traces of carbon, which is fundamental for life. They found that one of the zircons contained graphite - pure carbon - in two locations, shown below,