It would be hard to fit 3.7 billion candles on a cake, but if you threw a birthday party for these newly found fossils, that’s how many you’d need.

Researchers have discovered fossils in Greenland that date to 3.7 billion years ago, making them the world’s oldest fossils, according to the University of Wollongong in Australia.

The fossils are stromatolites that were originally created by microbes that lived in the distant past. Originally formed in what the researchers said was a shallow sea, the fossils were only discovered after snow in Greenland over them melted. 

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The discovery, made near the edge of Greenland's ice sheet, shows that life on our planet— which has celebrated about 4.55 billion birthdays—  began when it was still young.

“This indicates that as long as 3.7 billion years ago microbial life was already diverse,” Allen Nutman, a professor at the University of Wollongong, said in a statement. “This diversity shows that life emerged within the first few hundred millions years of Earth’s existence, which is in keeping with biologists’ calculations showing the great antiquity of life’s genetic code.”

Nutman is the lead author of a study reporting the discovery in the journal Nature.

The fossils are 220 million years older than fossils discovered in Australia that were previously believed to be the world’s most ancient.

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