How does natural selection drive changes in gene pools?

Natural selection drives changes in gene pools by favouring the survival and reproduction of the fittest individuals.

Natural selection is a fundamental mechanism of evolution, first proposed by Charles Darwin. It operates on the principle of 'survival of the fittest', where individuals with traits that enhance their survival and reproductive success are more likely to pass on their genes to the next generation. Over time, this process can lead to changes in the gene pool of a population, which is the total collection of genes and their variants in that population.

The process begins with genetic variation, which arises from mutations, gene flow, and sexual reproduction. These variations create a diverse range of traits among individuals in a population. Some of these traits may provide an advantage in the current environment, such as better camouflage, resistance to disease, or more efficient metabolism. Individuals with these advantageous traits are more likely to survive, reproduce, and pass on their genes to their offspring. This is known as differential reproductive success.

Over generations, the frequency of these advantageous genes increases in the population, while the frequency of less advantageous or detrimental genes decreases. This is because individuals carrying the advantageous genes are more likely to survive and reproduce, while those with less advantageous genes are less likely to do so. This process of differential survival and reproduction leads to changes in the gene pool, with advantageous genes becoming more common over time.

However, it's important to note that the environment determines which traits are advantageous. If the environment changes, traits that were once advantageous may become less so, and vice versa. This means that natural selection is a dynamic process, constantly shaping the gene pool in response to environmental changes.

In summary, natural selection drives changes in gene pools by favouring the survival and reproduction of individuals with advantageous traits. Over time, this leads to an increase in the frequency of these advantageous genes in the population, thereby changing the gene pool. This process is fundamental to evolution and the diversity of life on Earth.