The age of our planet is a little over four and a half billion years, and four billion of them it is inhabited by living organisms. That is the conclusion of a recent study was made by Japanese geologists from the University of Tokyo. Previously it was thought that life originated on Earth or even the 3.7 3.4 billion years ago.
In the course of works on the canadian island of Newfoundland experts have studied ancient rocks, formed around a 3.95 billion years ago. The researchers found in samples of many small voids containing graphite, which, with great probability, suggests that in those days the area was inhabited by ancient organisms.
Long been known that organic molecules cannot serve as direct evidence of the existence of living organisms or product of their activity. However, often some indirect evidence to suggest whether these or other structures of biogenic origin. In this case in favor of this assumption is illustrated by the low content of graphite in carbon-13, and the fact that many elements of graphite grains resemble bacteria in form.
Further study of the samples showed that the record of ancient microorganisms, in all probability, lived in salt water, fed with hydrogen or organic molecules and the result of their life converted carbon dioxide to carbon monoxide. In General, such a description is consistent with existing conceptions of what were to be the first in the history of the planet’s living creatures.
The study was published in the scientific journal Nature.
For a long time it was believed that life originated in the primary ocean of the Earth about 3.4 billion years ago, but over the last three years was found a certain amount of evidence that it happened three hundred million years earlier. A new study, according to its authors, allows to move this date to an even earlier period of the existence of the planet.