What process is responsible for the evolution of organisms that are best adapted to their environment?

Natural selection is the process that explains how organisms evolve traits that are best suited to their environment over time. It operates on the principle that individuals with advantageous traits are more likely to survive and reproduce, passing those traits on to the next generation. This gradual change leads to the adaptation of species to their habitats, enhancing their chances of survival and reproductive success.

Organisms that possess certain inherited characteristics that provide an advantage in their specific environment tend to produce more offspring than those without such traits. Over generations, these favorable traits become more common within the population, leading to the idea that the population is evolving. This concept was famously articulated by Charles Darwin and is foundational to our understanding of evolutionary biology.

Comparatively, genetic drift refers to random changes in allele frequencies in a population, which can lead to evolutionary changes but is largely based on chance rather than fitness. Artificial selection involves humans selectively breeding for desirable traits, which does not occur in natural contexts. Sexual selection is a subset of natural selection that focuses specifically on traits related to mating success, rather than overall survival in the environment. Each of these processes contributes to evolution in different ways, but natural selection specifically highlights how adaptations occur through differential survival and reproduction in response to environmental pressures.