The evolutionary history of life on Earth traces the processes by which living and fossil organisms have evolved since life appeared on the planet. The scientist has discovered what they say could be a fossil of some of the earliest living organism on Earth. Geologist uncovered the tiny tubular structure from ancient Canadian rocks dated to be up to 4.28 billion years old.

Matthew Dodd, who analyzed the structures at University College London, said that this discovery answers the biggest questions mankind. This discovery would shed new light on the origins of life. It is very humbling to have the oldest known life forms in hands and being able to look at them and analyze them, he told BBC News.

The fossil structures were encased in quartz layers in the so-called Nuvvuagittuq Supracrustal Belt (NSB).The NSB is a chunk of ancient ocean floor. It contains some of the oldest volcanic and sedimentary rocks known to science. Dr. Dominic Papineau from UCL who discovered the fossils in Quebec and he thinks this kind of setting was very probably also the cradle for life forms between 3.77 and 4.28 billion years ago.

As stated by Science journal, the clues lie hidden in microscopic flecks of graphite and a carbon mineral. Which is trapped inside a single large crystal of zircon, Zircons grow in magmas, often incorporating other minerals into their crystal structures of silicon, oxygen, and zirconium.

The scientist said that the analysis is complicated because the rocks in question have often undergone alteration. The earliest evidence for life on Earth is graphite found to be a biogenic substance in 3.7 billion-year-old metasedimentary rocks discovered in western Greenland and microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia.

 The UCL researchers and their colleagues say they have worked extremely hard to demonstrate the greater antiquity for their structures. Dr. Papineau does concede though that the idea of metabolizing microorganisms using oxygen so soon after the Earth's formation will surprise many geologists.

Some geologists presumed that these (NTB) organisms come from a time when Mars had liquid water on its surface and a similar atmosphere to Earth at that time. The life had already arisen just a few hundred million years ago. The Earth had formed is intriguing in light of debates about whether life on Earth was a rare accident or whether biology is a common outcome given the right conditions.