Deposits of organic rock found in eastern Canada indicate that life on Earth has existed for almost 4 billion years.
The earth formed about 4.5 billion years ago, and the oceans about 4.4 billion years ago. Previous research involving similar samples of a rock found in Greenland helped determine that life originated 3.7 billion years ago. New research by Japanese scientists confirms that life began much earlier.
The discovery was made by geologists from the University of Tokyo, after analyzing the composition of the rock found in the Canadian provinces of Labrador and Newfoundland, reports Reuters.
In biogenic graphite, the remains of primary marine microorganisms were found, whose fossils cannot be found after so many years, but traces of their vital activity have been preserved in the form of carbon. Scientists are not yet sure exactly what the early life forms were, but traces suggest they were bacteria.
To make sure they were looking at the waste product of microorganisms, the researchers examined graphite from 54 Canadian samples.
Moreover, geologists have determined that the samples are 150 Ma older than those from the Isua Formation (Greenland). Therefore, there is every reason to believe that life began to form carbon atoms already half a billion years after the formation of the planet itself.
The researchers clarify that these early microorganisms lived in the open ocean, in salt water.