It is believed that life on Earth occurred through a natural process by which life itself originated from non-living matter, such as simple organic compounds. But anyway, living beings on Earth exist today only because, before them, other beings have reproduced for billions of years.
But is there a purpose in all this why two bacteria are formed from one bacterium and so on? It would seem not because throughout the living world reproduction plays the specific role of being the purpose of each individual organism which excludes other purposes of organisms in general. We could use the words of Democritus: “Everything that exists is the fruit of chance and necessity”. And chance and necessity is precisely the title of a volume in which Jacques Monod, Nobel Prize winner for medicine and physiology in 1965, addresses the issues of heredity. From the genetic point of view, the living being represents the execution of a program which, however, no will has chosen and no intelligence has conceived. Analyzing the concept of inheritance means going through, one by one, all the stages of biology.
In the essay, Monod discusses the metaphysical and spiritual consequences of the great discoveries of molecular biology and genetics, and associates apparently inappropriate concepts such as chance or necessity with questions such as the origin of life or the evolution of species.
Who we are, what place we have in the universe, what meaning we give to our life, are all questions that man has always asked himself and continues to ask himself, uniting scientists and philosophers in this. Through the study of ancient DNA it is also possible to study our evolutionary history. This is what researchers from the Institute of Genetic and Biomedical Research of the National Research Council and UniSassari did, who published in Nature Communications the results of the analyzes carried out at the level of the entire genome on the DNA extracted from the prehistoric bone remains of 70 individuals, coming from from more than 20 Sardinian archaeological sites covering a period from the Middle Neolithic to the Middle Ages. “For this reason, today's Sardinians show a higher degree of genetic similarity with DNA samples extracted from prehistoric remains coming from the same territory but also from pre-Neolithic sites (over 10,000 years ago) in continental Europe.” The study confirms that these similarities are more marked in the historically more isolated areas such as Ogliastra and Barbagia.
Contemporary Sardinians therefore represent a reserve of ancient DNA sequence variants dating back to proto-European lines of ancestry, currently very rare in continental Europe. The genetic invariance of populations thanks to insularity and intra-region isolation has confirmed that genes also contribute to determining our character, our personality, our behavior. They are the result of the interaction between the genetic heritage that everyone inherits from their parents at the moment of conception and the environment in which they grow up and live.
The communities of Sardinia are still unique: with a similar vocabulary, traditional customs, rules and social relationships, based on friendships, acquaintances, recommendations. Unchanged over the centuries.
Antonio Barracca
