The process of natural selection refers to one of the mechanisms of evolution of the species of living beings, proposed by Charles Darwin and Alfred Russel Wallace, from which they explained the design of nature.
Natural selection occurs thanks to the progressive adaptation of the species to its environment. When individuals with certain characteristics have a higher survival rate than other members of a population, they pass these inheritable genetic characteristics to their offspring.
Natural selection is the central basis of all evolutionary change, being also the process through which the best-adapted organisms displace the less adapted by the slow and progressive accumulation of genetic changes.
The contribution of an individual to the next generation is recognized as biological efficacy, and it is a quantitative character that encompasses many others, related to the survival of the fittest and the differential reproduction of different genotypes.
The fundamental thesis of natural selection is that the traits are hereditary, but nevertheless, there is variability in the trait between different specimens. In this way, there is a biological adaptation to the environment, and only certain characteristics of the new apparitions extend to the entire population.
The generations are in permanent evolution, and it is precisely the set of variations that occur throughout the generations that constitute the evolutionary process.
Examples of natural selection
- The evolution of medicine is based precisely on the fact that from the use of antibiotics for viruses or bacteria it is possible to kill some of them, but those that survive become more resistant.
- The white fur of the arctic animals, which allows them to hide in the snow.
- The camouflage of grasshoppers, which makes them look like leaves.
- The movements of the male blue-legged gannet, to attract its mate.
- The giraffes, of which the longest neck survived.
- The color change of a chameleon when it has prey, or to protect itself.
- The process of cloning, constantly developing but already proven in the facts, could potentially interfere with natural selection.
- The brown beetles have a greater chance of survival, and have more descendants, the population becoming frequent.
- The case of the totality of the species that disappeared, and still continue to do so.
- The cheetahs, which have survived the fastest.
- The evolution of the human being in different species, called hominids.
- The deformation of the jaw of the snake to swallow larger prey.
- The change of coloration of some moths, motivated by the industrial revolution in England. (Here the change in the environment was generated by man)
- The bobbing dance of bees.
- The resistance to insecticides of some insects, which show the question of selection as a source of survival.
- The shape of the beak of the finches was modified over time because after the droughts they hardened allowing to eat harder seeds.
- The ability of human beings to learn to speak.
- The orchids that are capable of deceiving wasps so that they ‘mate’ with them.
- The non-poisonous king snakes, which mimic poisonous coral snakes.
- The courtship rituals of the birds.
Linear and continuous process?
The question of evolution implies an additional consideration because if the characteristics pass along the evolutionary process as explained, a linear sequence of species could be traced, getting to connect each of the genetic variabilities that were appearing.
Under this premise is that the evolutionary chain under which the idea of ?? a missing link was interpreted, a variability that is missing to fully describe an evolution. However, this is not what happens: evolution is endowed with ramifications, with mixtures between species and modifications according to different adaptations to the environment, which is a correction that leaves out this idea of a missing link.
The generalization of Darwinism
The question of natural selection was replicated through the analogy for other areas, and by extension, the idea of Darwinism explained precisely these areas, where the strongest and capable is the one that survives while those that are not so adapted do not. When it comes to social processes, it is evident that Darwinism is a very cruel and aggressive situation.
For the natural selection process to occur, it is necessary that the differential biological effectiveness exists, that the phenotypic type is variable, and that this variation occurs through inheritance.