The appearance of life on Earth has been a subject of intense discussions for many specialists. Scientists used Raman spectroscopy, a procedure that presents the chemical and molecular framework of fossil bacteria in 3D. They found that life appeared and possibly evolved long before it was initially believed. They analyzed several zircons with traces of graphite inside it. This heavy mineral can preserve extremely well the trapped content and this property permitted geologists to understand more about the Earth’s environment almost 4 billion years ago.
Since the analysis group already knows that zircon is more than 4 billion years old, the age of graphite is even older than that. The authors of these new tests and experts in geochemistry at the University of California, stated in a press release that decades ago, this idea would have been considered absurd and discovering proof of the existence of life older than 3.5 billion years ago was unheard of. It looks like that the earliest forms of life began very soon after Earth was formed, added the American specialists who are also members of the US scientific community.
These new studies indicated that life started prior to the large bombardment of our solar system, which created moon’s massive craters almost 4 billion years ago. During this intense bombardment, researchers theorized that these frequent hits left our planet with long and deep cracks, dry and looking like a wasteland. Furthermore, the scientists claim that this idea actually suits better the accelerated time line needed for the new genetic discoveries regarding the appearance of life.
US experts analyzed more than 10,000 pieces of zircon initially created from melted stones or magmas, found in Australia. The theory that life began to form more than 300 million years before it was believed until now represents the most intelligent and easiest explanation, but it is not definitive proof for this unusual idea. These zircons look a lot like imitation gemstones and they can capture and protect their immediate life forms, meaning that they can act like genuine time capsules for scientists.
During the course of their experiments, scientists created the advanced tools that allow them to evaluate the age groups of these prehistoric things, but they discovered in Australia two places where they have these fossils having almost the age of our planet. The researchers first tested some 656 zircons that contained a few black specks. Experts know these zircons are over 4 billion years old, depending on its proportion of lead to uranium, but they still do not know the age of graphite. To validate their findings about the age of life, the scientists had to detect signs of carbon, an element that is essential for the existence if life as we know it.
Not only is graphite a sign of life, but also its particular percentage of carbon-12 to 13 represents a clue for photosynthetic and organic processes, say the scientists, since a few minerals get attached to carbon-12. The group of geologists has made their colleagues to think even more about the age of the biosphere and how to discover new methods to decipher the mysterious history of it.
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