Darwin’s evolution theory, the story of a scientific revolution

There evolution theory Of Charles Darwin based on the mechanism of natural selection It has revolutionized the field of biology and is still considered one of the greatest scientific theories ever. This theory claims that individuals with characteristics that make them more suitable for the environment have greater probability of survivingreproducing and therefore handed down these sections to subsequent generations: this slow but constant “push” allows the species to evolve gradually over time. To get to the formulation of such a complex and articulated reasoning, Darwin put all the research and the observations collected in long years of travel Around the world and all the hypotheses formulated on the most disparate scientific subjects of which he dealt with in life. The story of the publication of his best known text, The origin of the specieshelps us to understand what we still remember as one of the major scientific revolutions ever.

What the theory of the evolution of Charles Darwin says: the fundamental points

Charles Darwin’s theory on natural selectionexposed in his book The origin of the speciesis one of the pillars of the evolutionary biology. Darwin claims that all living species, animals and plants derive from a common ancestor And they have diversified over time through a gradual process. The fundamental points of his theory are the variability of the characters, adaptation to the environment, inheritance of innate characters and geographical isolation. Within each population exist differences between individuals and individuals with characteristics more advantageous For the environment in which they live they are more likely to survive And reproduce. These favorable characteristics are transmitted over time to subsequent generations Going to change the populations in order to better adapt to the environment.

The evolution, explained by Darwin, is a natural and continuous process based on the interaction between organisms and the environment without external interventions. A classic example studied by the famous biologist are the FRINGUELLI DELLE GALAPAGOS: Each island of the Archipelago had birds with stinks of different shapes, adapted according to the specific sources of food present in that area.

Darwin’s historical context of Darwin

The text in which Charles Darwin proposed his theory on the evolution of specieswas published for the first time in London, the November 24, 1859and put scholars and researchers in the face of dynamics and issues that, at the time, had still been unwittingly debated. In The origin of the speciesfrom the full name On the Origin of Species by Means of Natural Selection, or the preservation of favoured races in the shit for life (which we could translate as “the origin of the species by natural selection, or the preservation of the varieties favored in the struggle for survival”), Charles Darwin condenses all his long studies, permeated and influenced by the work of illustrious colleagues and the numerous scientific discoveries, who made the nineteenth century a very important century for the history of science.

Among these scholars we remember, in particular, the Scottish geologist Charles Lyelland the pioneer of demography studies, Thomas Robert Malthus. Lyell, for example, made a spokesperson for a principle called uniformitarianismor actualismaccording to which everything we see on the surface of the earth corresponds to the result of theslow and gradual action of chemical, physical and biological processes. The actualism remarked by Lyell was proposed for the first time by the geologist James Hutton, as opposed to the catastrophismwidespread among the scientists of that time, according to which everything is basically motionless and the changes take place only following catastrophic events.

Thomas Robert Malthuson the other hand, was fundamental in the influence of Darwin’s thought, because he dealt with the construction of models concerning the size of human populations and the availability of resources, which in the theory on evolution by natural selection occupy a significant space.

THE’Origin of speciesa revolutionary publication

Charles Darwin He began to think about the origin and evolution of the species already during the long journey made on board the Brigantino Beagle. By his own admission we know that, already in 1844, much of the study on evolution theory was complete. Still, the English naturalist waited 15 years before publishing The origin of the species. We must remember that Charles Darwin was not the only one to experiment with a theory concerning theevolution of species and to study the changes that affect the living in a long period of time (we think, for example, a Jean-Baptiste de Lamarckwhich in 1809 had proposed a theory of evolution based on the inheritance of the acquired characters). There is more, in an article by the philosopher Herbert Spencerpublished in 1852, a reference to the evolution understood as a sort of survival of the most suitable individuals.

In short, the times were ripe and more scientists had reached similar ideas. To convince Darwin to publish his studies (which he will then see several times in the following editions) was, however, an essay received in the summer of 1858 by the naturalist Alfred Russel Wallaceat that time traveling to Indonesia, who in a moment of convalescence, due to the consequences of malaria, matured A theory based on natural selection Very similar to what Darwin had already hypothesized 15 years earlier.

Darwin, at that point, recognized the work of the colleague and, pushed by the most trusted friends (including the zoologist Thomas Huxley), he believed that the time had finally come to revolutionize the history of biology. So it happened that in the session of the Linnean Society of 1 July 1858, an essay was read “on the tendency of species to form variety and the perpetuation of varieties and species through natural selection“Signed by both authorsCharles Darwin and Alfred Russel Wallace. A very important moment, which culminated, a year later, with the publication of The origin of the specieswork that revolutionized biology, managing to identify the mechanism capable of explaining the diversity of living in the evolution by natural selection.