Or how, actually, it all started
About four billion years ago, a unique event took place on Earth. Until then, this planet was an arid and hot desert, with comets and asteroids frequently crashing into it. Boiling oceans condensed and evaporated, oil-like organic substances came from space or were formed by lightning and volcanoes, but there was no life. And here, for a relatively short period in geological terms, bacteria-like creatures appeared, whose traces are found today in the form of fossils in the rock.
This miraculous process, in which life was created "out of nothing", from inanimate matter, is still an enigma. There is currently no accepted explanation for the way in which this happened, and this is one of the main open questions in science. Only in recent decades has the power of this question become clearer. Modern molecular biology has proven that even the most primitive single-celled creature is a very complex molecular "machine". That is why some likened the emergence of the first bacterium from the "primitive soup" to the process in which a tornado passes through a huge scrap yard - leaving behind a shiny jumbo plane ready for takeoff.
Of course, that's not how it happened. It is widely agreed that gradual evolution played a central role even in the earliest stages of the beginning of life. But in order for this kind of development to be possible, the ability to reproduce must first exist, as described in the writings of Charles Darwin. The enigma of the beginning of life is therefore summed up in the following question: what is that entity that was simple enough to appear spontaneously, and at the same time also complicated enough to be capable of self-replication.
There are two competing theories on this issue, and the arguments between their supporters are sky high. Most scientists agree that this is a problem in the field of chemistry and not a philosophical or metaphysical question. But opinions differ regarding the individual mechanism. A beautiful and fair description of this scientific controversy appears in Iris Frey's book "The Origin of Life" (Broadcast University, published by the Ministry of Defense).
The first theory was published in the XNUMXs by the Russian scientist Alexander Oparin. This theory holds that the first replicator (replicator) was a cluster of particles (molecules) inside a tiny oily drop, and that the chemical interactions between them made possible the creation of additional copies of the entire collection.
Much later, based on discoveries made in the past half century, Nobel laureate Manfred Eigen and others presented the second theory, according to which the first replicant was a single individual and not a collection. The main reason for this transformation was the discovery that at the heart of every living cell there are chain fragments of the type DNA and RNA (known as nucleic acids), endowed with a special ability. Under certain conditions, and with the necessary help of enzymes (protein catalysts), these mares create copies of themselves and thus transmit genetic information from generation to generation. The adherents of the solitary separate have therefore proposed that the first RNA chain was formed in the ancient soup, and it was the one that was the first seed for all life. This scenario now appears in most textbooks.
In modern science it is rare that deep disputes remain unresolved. Experiments and careful observations allow scientists to reconcile the contradictions and decide which of the hawks is right. In this respect, the beginning of life poses an extremely difficult challenge. It seems that the chances of discovering remains of the first simple replicants are slim. Most scientists in the field are also convinced that it will be extremely difficult to reproduce the appearance of the first living cell under laboratory conditions. It is possible that life can only be created in a huge "laboratory", the area of which is the entire surface of the earth, and that the duration of the "experiment" required is tens of millions of years.
As such, the debate continues. The adherents of the one-pronged replicator publish exciting new studies in the field of the "RNA world", and it seems that soon they will be able to produce self-replicating RNA. The opponents sometimes find themselves as a persecuted minority, but gradually their power increases. The central claim of the followers of the collection is that RNA capable of replicating itself without any help from other substances, such as proteins, is an almost impossible phenomenon under the conditions that prevailed on the ancient Earth. They even hold that even if a cell of this kind is created, there is still a long way to go from it to the multifaceted entity that is a living cell.
Adherents of the Genesis collection point out that even today's living cell is actually a collection of different and odd parts, and claim that it is more likely that a simple collection gradually turned into an elaborate collection. They mobilize alongside them modern scientific tools, such as simulations on supercomputers and concepts from the field of nanotechnology (superminiaturization), to draw a more detailed and realistic scenario of the idea of the fat droplet with the replicating collection. The results of the Genome Project are also used as a reference here, as they depict the living cell today as a molecular collection controlled by a complicated network of mutual reactions. This kind of mechanism bears a surprising resemblance to the one proposed for the initial mule collection.
It is possible that the rescue will come from one of the most exciting fields in the context of the beginning of life, aka astrobiology. Already Viking spacecraft that landed on Mars in the seventies did robotic experiments to detect signs of life. The controversial publication of possible remains of living entities in a meteorite that splashed from Mars and landed in Antarctica added fuel to this fire. Some even claim that life came to the earth from another world (pan-spermia), but in doing so they only move the main question to a distant place. In recent years, the American space agency sees the discovery of the remains of extraterrestrial life as a central task. It is therefore possible that the intriguing question about the beginning of life in Israel and in the entire universe will eventually be answered in a futuristic journey across the galaxy.
