London, Europe Brief News – A new study has revealed that life on Earth could have begun much earlier than widely assumed.
The evidence comes in a fist-sized rock from Quebec, Canada, which is estimated to be between 3.75 and 4.28 billion years old.
Inside this rock, scientists at University College London have found a mysterious, complex plant-like structure.
The rock was collected from the Nuvvuagittuq Greenstone Belt (NGB) formation which contains some of the oldest rocks on the surface of the planet.
It was once part of the seafloor and although scientists aren’t sure whether that was 3.75 or 4.28 billion years ago, it remains a vital location for evidence of the very distant past.
A new study of the rock collected from the NGB found tiny filaments, knobs and tubes inside of it which appeared to have been made by bacteria.
If confirmed, it would suggest the conditions necessary for the emergence of life are relatively basic.
“If life is relatively quick to emerge, given the right conditions, this increases the chance that life exists on other planets,” said Dominic Papineau, of University College London, who led the research.
Five years ago, Papineau and colleagues announced they had found microfossils in iron-rich sedimentary rocks from the Nuvvuagittuq supracrustal belt in Quebec, Canada. The team suggested that these tiny filaments, knobs and tubes of an iron oxide called haematite could have been made by bacteria living around hydrothermal vents that used iron-based chemical reactions to obtain their energy.
Scientific dating of the rocks has suggested they are at least 3.75bn years old, and possibly as old as 4.28bn years, the age of the volcanic rocks they are embedded in. Before this, the oldest reported microfossils dated to 3.46bn and 3.7bn years ago, potentially making the Canadian specimens the oldest direct evidence of life on Earth.
Now, further analysis of the rock has revealed a much larger and more complex structure – a stem with parallel branches on one side that is nearly a centimetre long – as well as hundreds of distorted spheres, or ellipsoids, alongside the tubes and filaments.
