We have two very different answers. If we opt for the religious: God created life . If we speak with scientific property: we do not know .
Calm down, you see that this article continues and it is not that we are going to debate whether Superman flies or jumps a lot. Almost none of the universal questions we ask ourselves have clear answers. Science is doubt, skepticism and curiosity par excellence. Therefore, a complex question will not have one, but several answers. You can choose your favorite yourself. If you want to stay with the religious answer, we recommend reading Genesis, the first book of the Bible. If you want to know how such a difficult question is approached scientifically, read on.
The begining of everything
Our solar system has an origin that is dated (as of the day I am writing this, at least) 4.6 billion years old. The Earth is about 4.57 billion years old . It is not that they were born as we know them today, as you can imagine, but that they had a long process of formation and growth. In fact, it was a key process for life (or so we think).
The Earth was hoarding stellar matter that passed by its side. Haunted by impacts, our planet spent millions of years with very high temperatures, but, as soon as the stellar bombardment subsided, the crust, the mantle, the oceans, the atmosphere and all those characteristics of the Earth that so many pleasant mornings were formed. they gave at school
How do we date the origin of life? Well, since there is no certainty, we are satisfied with a range that goes from when we think that life could have arisen, until when we are already sure that there was. That brings us to a chronology between 3.850 and 3.7 billion years ago . In those 150 million years (from nothing) life arose on Earth, and we do not know if it was a process more or less extended in time.
Problem: As you know, the Earth is constantly changing. In 150 million years, imagine the number of geological processes that can occur. To give you an idea: in about 150 million years Pangea separated and the continents were arranged as we see them today on a map. In other words, it gives time for America to separate from Africa and Eurasia and a whole new ocean (the Atlantic) to form. And due to this inconcretion and possible variations we have the different hypotheses about the origin of life.
Spontaneous generation
In the middle of the fourth century BC, Aristotle said that living beings arose from nothing, spontaneously, like a mushroom. You would think that this theory was held for a short time, but it was not until the 17th century that another theory that was not theological had any weight.
Francesco Redi set up an experiment with three pieces of meat under different conditions and observed them to see if life arose spontaneously. Only in one of them did larvae emerge: the piece of meat that the flies could access. Therefore, Redi objected, against Aristotle, that life did not generate itself, but that it was the flies that planted their larvae there, while the other two pieces of meat knew no life at all. However, the experiment did not eliminate all Redi’s doubts: why did the three meats rot equally? How were they contaminated? The arrival of the microscope and the discovery of bacteria would be the answer to Redi. Another scientist would be in charge, two centuries later, of finishing the work started by him.
Louis Pasteur carried out an experiment in 1860: he boiled water to eliminate all the microorganisms it contained (hence “pasteurization”), and managed to isolate the water so that no bacteria could enter it that could contaminate it. The water remained unpolluted and Pasteur put an end to the theory of spontaneous generation . More than twenty centuries (you’re welcome) it took us.
the broth of life
Darwin already hinted that the origin of life could be a matter of chemistry. He did it in private letters sent to a friend, in his time he had enough with the evolution of the species to publicly deny God’s creation.
In 1920, Alexander I. Oparin and John BS Haldane took Darwin’s theories to the experimental level. It was not a study in pairs, Oparin in the Soviet Union and Haldane in England, reached similar conditions. Grosso modo , they came to say that the elements that were part of the atmosphere could react with each other by phenomena such as electric discharges. Molecules of all kinds would be concentrated in the water and a mixture of compounds would have given rise to proteins that began to replicate. In the 1950s, Stanley L. Miller and Joan Oró managed to generate molecules by recreating the atmospheric environment described by Oparin and Haldane. But from proteins to a living being there is some other difference.
Are we aliens?
Among many other theories, we have that of panspermia : life would have arrived on our planet mounted on an extraterrestrial rock. This already smells like it’s hard for us to recognize that we have no idea how life originated. But the reality is that organic matter has been found in meteorites.
Undoubtedly, the origin of life is one of the questions that remains to be studied in greater depth and from which the most theories have been derived from laboratories. Fortunately, science is advancing by leaps and bounds and, who knows, maybe one day we will be able to show how life began in this world.
References:
Bermudez, JM et all. 2015. Origins: The Universe, Life, Humans. Criticism.
Vicente, A. et al. 2018. In search of the lost origin. Paid.
