Sciences: the emergence of life on Earth would be older than previously thought – Le Parisien

L has life on Earth dates back longer than previously thought. Australian researchers have highlighted this major discovery based on the discovery of fossils in Greenland at least 3.7 billion years ago, 220 million years before the oldest traces of life known until now.

“This discovery sets a new benchmark” in the search of the first traces of life on Earth, said in a statement Julian Martin Van Kranendonk, expert in geology from the University of new South Wales South and co-author of a study published in the British journal Nature. These fossilized structures called stromatolites, prove that life had already appeared some 800 million years after the formation of the Earth itself, dating back 4.5 billion years, according to Allen Nutman Australian University Wollongong, lead author of the study.

These geological formations have emerged to the surface after the melting of an ice sheet in the massive Isua, in south-west Greenland . The structures and chemistry of these fossils suggest to microbial activity and thus “to a biological origin” sign “a rapid emergence of life on Earth,” according to Allen Nutman. Stromatolites, high of 1 to 4 cm, corroborate other genetic evidence that place the origin of life at this time.

According to the study, this discovery could also help research life on Mars, considered the planet of the solar system most conducive to the existence of life forms because it has an atmosphere containing water as vapor and ice. “There are 3,700 million years ago, Mars was probably still wet, with even oceans,” said Allen Nutman. “If life has grown so rapidly on Earth, allowing the formation of stromatolites things like these, it might be easier to detect signs of life on Mars.” “Instead of only studying the chemical signature of the planet, we may be able to see things on the Mars images as stromatolites,” he said.

Up today, the eve evidence of life on Earth was discovered by Australian and Canadian researchers in the rocks of Strelley Pool Chert in the Pilbara region in Autralia. It had about 3.5 billion years.