Final answer:
Artificial selection, or selective breeding, is a true practice where humans breed plants or animals with desirable traits. This process is akin to Darwin's natural selection but is driven by human choices rather than environmental pressures, demonstrating how selective pressures can alter species.
Step-by-step explanation:
Artificial selection, also known as selective breeding, is indeed practiced by farmers. This process involves selecting specific plants or animals to breed based on desirable traits they possess. For instance, a farmer might breed cows that give more milk and avoid breeding those with lower milk production, thereby enhancing milk quality and quantity over generations.
Artificial selection is similar to natural selection in that both processes lead to differential reproduction based on favored traits. However, the key difference lies in the fact that human intervention drives artificial selection, whereas natural selection is driven by environmental factors that determine which traits enhance survival and reproduction without direct human involvement.
Darwin's theory of evolution by natural selection provides a natural counterpart to artificial selection, with the latter offering evidence that selective pressures can lead to significant changes in species over time.