A team of researchers claims to have made an extremely rare discovery, namely the oldest fossils on Earth. The fossil, which is between 4.3 and 3.8 billion years old, is the oldest evidence of the existence of life on Earth. What is striking is the fact that they appear to be similar to bacteria found on seafloor hydrothermal vents.
The research was led by University College in London, but also involved scientists from the University of Ottawa. They stated that the fossils were at least 3.8 billion years old, and they might even be as old as 4.3 billion years.
The fossils are incredibly tiny. They have almost half of the width of a human hair. The researchers discovered it in Northern Quebec, from the Hudson Bay near the Nastapoka Islands. This area is called the Nuvvuagittuq Supracrustal Belt. Since they are so tiny, the microfossils contain filaments and tubes that are half a millimeter long.
These filaments come in different shapes and are made up of an iron oxide called hematite. The scientists suspect that these filaments housed bacteria similar to that found on the seafloor.
With the passage of time, the vent systems helped them thrive and evolve into more complex life forms and this is how life on Earth started. The scientists think that these initial life forms emerged from the hot vents on the seafloor shortly after the formation of Earth. From a geological point of view, they are closer to the Earth’s formation than to the present day.
The fact that the structure of these fossils is similar to present-day bacteria found the hydrothermal vents suggests that the composition of rocks and other microorganisms in the sea remained constant over billions of years.
This discovery suggests that life emerged on Earth at a time when both Earth and Mars hosted water in liquid form on their surfaces. This gives researchers some hope regarding extraterrestrial life. They hope that they can find evidence of life on Mars from 4 billion years ago.
If they cannot find this evidence they are looking for, they might come to the conclusion that Earth was one happy exception.
There are some people who are skeptical regarding these fossils. They suggest that they do not represent fossils, but rather some structures formed during the geological processes. Their skepticism is given by the fact that the oxygen concentration was quite low on Earth shortly after its formation so, at the beginning, the planet could not sustain life.
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