July 16, 2021, 14:21 GMT
Microfossils have been found in southern Africa and are expanding the boundaries of potentially habitable environments on our planet and beyond, the discovery’s authors estimate.
Two thin layers extracted from a rock collected in South Africa contain the fossilized remains of what may be one of the first microorganisms on Earth. According to dating conducted by an international scientific team in a study published in the journal science progressThey inhabited the sea floor near geothermal sources about 3420 million years ago.
The specimens are found in the Makhungua Mountain Range – also known as the Barberton-Greenstone Belt – which contains some of the oldest and best-preserved sedimentary rocks on the planet. Identified microfossils, which have a carbon-rich outer shell and a chemically distinct core, Consistent with cell walls Or the membranes that surround the intracellular substance.
The study’s lead author, Associate Professor Barbara Cavalzi, sees in these ancient layers “exceptionally well-preserved evidence of fossilized microbes that appear to have proliferated on the walls of Cavities created by warm water from hydrothermal systems A few meters below the sea floor.
This primitive habitat harnessed the heat of underwater volcanic activity to host “some of the oldest microbial ecosystems on Earth”Older example that we’ve found so far,” explains the scientist at A Release from the University of Bologna, which led the research.
Chemical analysis of the samples showed that both layers contain Most essential elements of life. Nickel is also present, the concentrations of which in organic compounds indicate how primitive metabolism might be and correspond to the levels of this metal element present in Modern microbes known as archaea, living in the absence of oxygen and They use methane for your metabolism.
The identification of these fossilized microorganisms as prokaryotes means that they may not have had nuclei, but had DNA displayed in their cytoplasm. The lead researcher explained that although there is evidence that archaea can be fossilized, scientists have had very few direct examples of this ability. South African research and analysis expand the fossil record for this category for the first time to The era in which life barely arose on our planet.
Cavalazzi concluded that, as is the case too Similar environments On Mars, the study could have “implications for astrobiology and the possibilities of finding life beyond Earth”.
If you like it, share it with your friends!