DAT High Yield Biology Practice Test

Natural selection is fundamentally characterized by the competition among individuals for survival and reproduction within a given environment. This principle is rooted in the idea that individuals with advantageous traits are more likely to survive and reproduce, thereby passing those traits on to the next generation. The competition can stem from various factors, such as limited resources, predation, environmental challenges, and disease. As a result, those individuals best suited to their environment—often due to random variations or mutations—are more likely to thrive, ultimately contributing to the evolution of species over time.

The presence of random mutations can influence the genetic diversity on which natural selection acts, but mutations themselves are not an intrinsic characteristic of the process of natural selection. Likewise, the Hardy-Weinberg principle describes a state of genetic equilibrium in a population and does not apply when natural selection occurs, as it disrupts that equilibrium through differential survival and reproduction. Migration leading to gene flow can introduce new genetic material into a population, but it is a separate mechanism of evolutionary change that interacts with natural selection rather than a direct characteristic of it.