Researchers in Canada discover fossils of some of the earliest forms of life on Earth dating back some 4.28 billion years.
An international group of scientists claims to have found in a fossil stone the oldest signs of life on Earth dating back up to 4.28 billion years, according to the magazine Science Advances.
“Using many different lines of evidence, our study strongly suggests that a number of different types of bacteria existed on Earth between 3.75 billion and 4.28 billion years ago. This means that life might have started as little as 300 million years following the formation of the Earth. In geological terms, this is fast: regarding one lap of the Sun around the galaxy,” said Dominic Papineau, lead author of the study.
The evidence was discovered in a fist-sized rock found in 2008 by Papineau in the Nuvvuagittuq Greenstone Belt (NGB) in Quebec, Canada. In A study In 2017, the team found filaments, bumps, and ducts in the stone that appeared to have been created by bacteria.
However, some experts questioned whether the markings, which date to some 300 million years before what is considered the first sign of ancient life, were biological in origin. Following more detailed analysis over subsequent years, the team found a stem with parallel branches on one side nearly a centimeter long, as well as hundreds of distorted spherical structures near tubes and filaments.
Specialists estimate that some of these structures might be generated through casual chemical reactions, but the stem, with high probability, was of biological origin, since no structure has been found as it is generated only by chemistry, they explain in a communicated from University College London (United Kingdom).
In addition, scientists discovered mineralized chemical by-products, indicating that the bacteria, which left signs of life in the stone, were feeding on iron and sulfur, as well as carbon dioxide through a form of photosynthesis that does not involve oxygen. .