Piece of History

Earth’s Oldest Fossil Uncovered

Celia Hameury
Contributor

When did life on Earth begin? It’s a question that has never quite had a clear answer. According to recent studies, however, it seems the magic number may be 3.7 billions years ago.

Earth’s oldest known fossil was discovered in late August by Australian researchers studying rocks in south-west Greenland, long hidden beneath layers of snow and ice. Some of these rocks bore miniscule lumps, one to four centimetres tall. Although the results remain unconfirmed, scientists believe that the curious humps may be the fossilizing patterns of stromatolites, which are microbe structures. Of course, this may not seem like much, but its implications are surprisingly broad.

The newly-found fossil pre-dates all others by at least 220 millions years. Until this discovery, the oldest known trace of life was a 3.4 billion year old fossil of stromatolites found in Australia. The new findings suggest that life on Earth may have originated only a billion years after the Earth’s formation, 4.6 billion years ago. This involves much swifter evolution than previously estimated.

Furthermore, it would imply that 3.7 billion years ago, the Earth was not a hellish wasteland of lava as was formerly believed, but rather a cooler planet with water at it’s surface, orbiting a sun about 30% dimmer than it is today. Studies of Mars indicate that the red planet displayed similar features around the same time period. Thanks to this new fossil, the idea of Mars once harbouring life might actually not be so far fetched after all.