Analysis of rocks taken in South Africa revealed microfossils of microbial life that evolved around hydrothermal vents 3.42 billion years ago. The discovery could help understand how life first appeared on Earth. It could also have implications for exobiology, in our pursuit of the organisms of the solar system.
The development of life took place in stages in which states of structured matter, intermediate between the inanimate and the living, gradually appeared. But where did these transformations take place? This question has led to long debates in biology. Was life formed in a warm little pond? Or on the seabed around hydrothermal vents? Article published in scientific progress It does not solve the question, but invites you to lean towards the second option.
3.42 billion year old microbes
As part of the latest work, a team led by Professor Barbara Cavalazzi of the University of Bologna has discovered microfossils that attest to the presence of life around hydrothermal vents. 3.42 billion years. This remnant of life was isolated from rocks extracted from the Barberton Greenstone belt in South Africa.
“We have found well-preserved evidence of fossilized microbes that appear to have thrived along the walls of cavities created by hot water from hydrothermal systems a few meters from the seafloor.”The researcher identifies himself in a press release. “Underground habitats, which have been warmed by volcanic activity, may have hosted some of the oldest microbial ecosystems on Earth and this is the oldest example we have found to date.”.
The filaments of microfossils discovered in South Africa are so well preserved that researchers have been able to identify carbon-rich cell walls and several nuclei. The high concentrations of nickel isolated in these fossils also indicate that the archaic prokaryoticLife forms today evolve in hypoxic (oxygen-free) environments depending on on methane To feed the metabolism.
Present these fossils and we know that life on Earth may be even older. Molecular clocks suggest they evolved at least four billion years ago. fossils Oldest discovered yet (In Greenland, although this is disputed) it is also 3.77 billion years old.
The study could also have implications for exobiology, potentially increasing our chances of finding extraterrestrial life. Then our eyes turn to Europe (Jupiter) in Encelad (Saturn), two icy moons that can support hydrothermal activity on the subsurface ocean floor.
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