Description: Natural selection is the process by which species adapt to their environment, favoring the survival and reproduction of individuals with advantageous traits. This mechanism, proposed by Charles Darwin in the 19th century, is based on genetic variability within a population and competition for limited resources. Over generations, traits that enhance an organism’s ability to survive and reproduce become more common in the population, while those that are disadvantageous tend to disappear. Natural selection is not a conscious process; it occurs naturally over time, driven by factors such as climate, food availability, and predator pressure. This concept is fundamental to understanding the evolution of species and biodiversity on our planet, as it explains how organisms adapt to changes in their environment and how new species arise from common ancestors. Therefore, natural selection is a cornerstone of evolutionary biology, providing a framework for studying the history of life on Earth and the interconnectedness of different life forms.
History: Natural selection was formulated by Charles Darwin in his work ‘On the Origin of Species’, published in 1859. Although the idea that species change over time existed before, Darwin was the first to provide a clear mechanism for this process. Along with Alfred Russel Wallace, who independently reached similar conclusions, Darwin established the foundations of modern evolutionary theory. Over time, natural selection has been confirmed and expanded by discoveries in genetics and molecular biology, integrating into the modern synthesis of evolution.
Uses: Natural selection is used in biology to explain the evolution of species and the adaptation of organisms to their environment. It is also fundamental in fields such as ecology, conservation, and evolutionary medicine, where resistances to diseases and the evolution of pathogens are studied. Additionally, it is applied in agriculture and animal breeding, where desirable traits in crops and breeds are selected.
Examples: An example of natural selection is antibiotic resistance in bacteria, where strains that develop mutations allowing them to survive these medications become more common. Another case is that of the moth species Biston betularia, which changed its coloration in response to industrial pollution during the Industrial Revolution, favoring darker variants in polluted environments.
