The discovery of 3.7-billion-year-old stromatolite fossils in remote Greenland by a team led by University of Wollongong researcher Allen Nutman shows that life on Earth got going pretty fast. Our blue planet is about 5 billion years old.

"This indicates that 3.7 billion years ago microbial life was already diverse. This shows that life emerged within the first few hundred million years of Earth's existence, which is in keeping with biologists' calculations showing the great antiquity of life's genetic code," Professor Nutman said.

Speaking to Fairfax Media, he said that there were now two very different strands of evidence pointing to the early rise of life on Earth – the stromatolite fossil record along with geneticists calculating the provenance of the genetic code back in time.

The research, funded by the Australian Research Council, is published on Thursday in Nature. In that paper, Professor Nutman and his colleagues Vickie Bennett from the Australian National University and Martin Van Kranendonk from UNSW, write that by "3700 million years ago life already had a considerable prehistory and supports model organism chronology that life arouse during the Hadean [epoch] more than four billion years ago".

Stromatolites fossils are mounds of carbonate constructed by communities of ancient single-celled microbes. For most of its existence, life on Earth has taken the form of single-celled bacteria.

Amazingly, stromatolites still grow at places such as Shark Bay in Western Australia.

The nature of the fossil record shows these single-celled organisms were already co-operating as communities 3.7 billion years ago.

Professor Nutman wrote: "Stromatolites are the most persistent evidence of life in Earth history and are known from the present to 3.48 billion years ago in the rock record."

The previous record for the oldest fossil was also of stromatolites in the Pilbara. These fossils are 220 million years younger than those found in south-west Greenland.

But how do they assist in the search for evidence of life on Mars?

Professor Nutman said: "We now have tangible visual signs of life on Earth in the same period that there was water on Mars. It's not a huge assumption to say that any life on Mars at this time was also single-celled micro-organisms."

Professor Martin Van Kranendonk is director of the Australian Centre for Astrobiology at UNSW. He said this research could help scientists look for similar structures on Mars, which was a damp environment 3.7 billion years ago.

"This discovery represents a new benchmark for the oldest preserved evidence of life on Earth," Professor Van Kranendonk said. "It points to a rapid emergence of life on Earth and supports the search for life in similarly ancient rocks on Mars."