Researchers have come across what they believe to be the oldest fossils ever discovered in Greenland, according to a new study, "Rapid emergence of life shown by discovery of 3,700-million-year-old microbial structures," that was published in the journal Nature on Wednesday. The fossils have been dated to 3.7 billion years ago, 220 million years earlier than the previous oldest dated fossils to have been discovered. The Guardian reports that the discovery could have a huge impact about how we understand the beginnings of life on earth. 

The fossils found are called stromatolites, layers in rock structures that are created by microbial activity. An independent researcher, Clark Friend​, co-authored the study and told the Guardian that this discovery is important for understanding the formation of life on earth. "Up until now the oldest stromatolites have been from Western Australia and they are roughly 3,500 million (3.5bn) years [old]," he said. "What we are doing is pushing the discovery of life earlier in Earth’s history."

While the exact nature of the microbes are not currently known, Friend told the Guardian that based on where the rocks were found and the time the microbes would have been active, they would have lived in shallow water. 

Perhaps most excitingly, Friend says that the discovery of fossils this old could provide insight for questions about the existence of life on Mars. "If we have got life at 3,700 million (3.7 bn) years on Earth," Friend said, "did it exist on other planets, because Mars, for example, 3,700 million years ago was wet."