What is the primary factor driving natural selection?

Natural selection primarily operates through the influence of environmental pressures, which create selective advantages or disadvantages for certain traits within a population. When individuals within a species display variations in traits, those variations may offer better survival or reproductive success depending on the specific challenges and conditions of their environment. For example, animals that are better camouflaged may escape predators more effectively, leading to a higher chance of survival and reproduction.

The environmental pressures include factors such as climate, availability of food, presence of competitors, and threats from predators or diseases. These pressures play a critical role in shaping the traits that are advantageous for survival and, ultimately, influence which traits are passed down to future generations. Over time, these selective pressures contribute to the evolution of the species as advantageous traits become more common within the gene pool.