Final answer:
Natural selection is the process where individuals with favorable heritable traits tend to survive and reproduce more successfully, influencing the evolution of populations. It leads to adapted populations over time and is driven by genetic variability and environmental pressures.
Step-by-step explanation:
Natural Selection and its Role in Evolution
The process by which individuals with certain heritable characteristics survive and reproduce more successfully than other individuals because of those characteristics is known as natural selection. It plays a crucial role in the process of evolution by ensuring that those individuals most adapted to their environment have a higher likelihood of surviving and passing on their favorable traits to the next generation. When environmental changes occur, genetic variability within a population can result in some individuals being better suited to the new conditions. These individuals are more likely to survive and successfully reproduce, leading to a shift in the population's genetic makeup over time. This phenomenon is also described by the concept of "survival of the fittest."
Population genetics studies how these selective forces change allele frequencies in a population over time, contributing to evolutionary change. The favorable traits that are inherited by subsequent generations are a result of successful individuals transmitting their genes more frequently, thereby affecting the gene pool of the population. Natural selection acts on the phenotype of an organism—the observable traits which are subject to environmental pressures.
Overall, the process of natural selection results in populations that are increasingly well-adapted to their environment, contributing to the broader pattern of evolution observed in nature. This process is driven by competition and the struggle for existence, where the most suitable variations provide a significant survival and reproductive advantage.