Scientists find traces of life dating back four billion years
British scientists found a 3.7 billion-year-old stone bearing traces of microorganisms. It appears that these traces are probably the oldest evidence of life on Earth known to man so far.
Microfossils about 4.3 billion years old found in Canada belonging to a bacterium-like species of microorganisms now growing around seafloor hot air vents may represent the earliest known evidence of life on Earth, researchers said. The researchers added that the fossils found on the shores of Hudson Bay in northern Quebec near the Nastabuca Islands support the hypothesis that the craters that spew hot air may have been the cradle of life on Earth after the formation of the planet.
The researchers said they believe that Mars - the closest planet to Earth - at that time had oceans that may have provided similar conditions conducive to the start of life. The study, published in the journal Nature, stated that microfilaments and tubes that take the form of iron oxide - or rust - and were formed by microorganisms were found surrounded by layers of quartz. Experts estimated that their age ranges between 3.77 billion and 4.24 billion years. Scientists said they were confident that the fossils, found in northeastern Canada, were formed by living organisms.
Researchers are likely to be the oldest fossils on Earth
They explained that they were primitive microorganisms similar to those that set off the path of evolution towards complex life and the eventual emergence of man 200,000 years ago. "Understanding how and when life began on Earth helps answer age-old questions: Where did we come from? Is there life elsewhere in the universe?" said Matthew Todd, a biochemist at University College London who co-authored the study. The researchers said that the structure of primitive microorganisms is very similar to the structure of modern bacteria that live near hydrothermal vents rich in iron.
Scientists believe that it - like its modern counterparts - feeds on iron. The land was formed 4.5 billion years ago and the oceans appeared about 4.4 billion years ago. Todd said that if the fossils were really 4.28 billion years old, that would indicate "an almost simultaneous emergence of life" after the formation of the oceans. The fossils appear to be older than any other previously discovered evidence of life on Earth.
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