An international team of geologists, physicists, biologists and astronomers has come together to create the most plausible version of the origin of life. According to scientists, a huge celestial body that collided with the Earth in the distant past is to blame.
According to many cosmological theories, destruction is not an arbitrary chaos, but a process necessary for creation, since it is he who clears the way for future growth and development. In 2018, Stephen Benner, an origin-of-life researcher at the Florida Applied Molecular Evolution Foundation, invited geologists, chemists, biologists, and planetary astronomers to share their theories about how life began on Earth. Using facts and evidence from various fields of science, experts tried to piece together this unique puzzle and formulate new theories of the appearance of complex molecules such as RNA. Unlike double-stranded DNA, ribonucleic acid is found in all living organisms without exception and is responsible for the synthesis of proteins in living cells.
As a result, a very interesting hypothesis gained the greatest popularity. According to her, some huge celestial body (in fact - a cosmic rock) collided with the Earth about 4.5 billion years ago. The collision turned it into a whirlpool of molten iron, which explains the presence of iron oxides and other metals on the planet's surface. This event had such a powerful effect that it destroyed many molecular bonds and led to the enveloping of the planet in a veil of hydrogen, which ignited and burned for another 200 million years.
It was this hydrogen isolation that, in the end, could theoretically set the stage for the formation of RNA. The exact chemical pathways by which this happened are still the subject of heated debate and experimentation, but a consensus has emerged around the idea of an RNA world.
This theory suggests that the "building blocks of life" appeared on Earth several hundred million years earlier than is currently believed. This shift in the graph is consistent with the latest research in geology and chemistry - in addition, in such a scenario, cellular forms would have enough time for evolutionary development. This is how scientists explained the "mystical" traces of microbes in the fossils, which are 3.5 billion years old.
In fact, there are catalogs of many complex experiments and theoretical models that have been created to prove and attempt to replicate chemical evolution. However, let us dwell on two important factors: firstly, ribose could survive only in a liquid medium, which is necessary for the first organic reactions, otherwise the substance will overheat and decay will begin. And in order for water to exist in a liquid state, it is necessary for the planet's temperature to drop below 100 degrees Celsius.
This is where Benner's new theory of the humid-dry climate of the Earth comes into play. Its indirect evidence is ancient mineral deposits, the so-called zircons. Together with research teams from the United States and Japan, Benner proved that sulfur dioxide (a product of volcanic activity) reacts with formaldehyde to form hydroxymethanesulfonate, or HMS for short. During a drought, a lot of such compounds would accumulate on the surface, and when the rains began, the water naturally carried it into lakes and reservoirs, where HMS met with an "organic broth" full of RNA precursor molecules, forming the notorious minerals.
Benner's theory is backed up by University of Colorado geologist Stephen Moijsis, whose work suggests that the earth's metal-rich surface is the result of rain of debris from a planet colliding with a large object. The "scars" from this collision, according to the scientist, remained in the form of certain isotopes of uranium and lead.
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However, even despite the validity of the new theory, scientists have not yet been able to explain the phenomenon of self-copying RNA. But such unanswered questions do not discredit the theory, but only fuel the interest of scientists, prompting them to further research and search for truth.
Vasily Makarov