Define genetic drift.

Genetic drift refers to the random fluctuations in allele frequencies within a population from one generation to the next. This phenomenon occurs due to chance events rather than because of natural selection or selective pressure. In smaller populations, these fluctuations can lead to significant changes over time, potentially resulting in the loss of genetic variation or the fixation of certain alleles. The randomness of genetic drift means that it can lead to unpredictable evolutionary outcomes, contrasting with the more directional influence of natural selection, where advantageous traits are favored and become more common in the population. This distinction underscores the important role genetic drift plays in shaping the genetic structure of populations, particularly in isolating effects and evolutionary bottlenecks.