Why is genetic variation critical for species adaptation?

Genetic variation is critical for species adaptation because it introduces a range of different traits within a population. This diversity means that some individuals might possess characteristics that make them more suitable for surviving in changing environments. When conditions such as climate or resource availability shift, those individuals with advantageous traits are more likely to survive, reproduce, and pass those traits on to the next generation. This process enhances the overall adaptability of the species, allowing it to persist despite environmental stresses or changes.

In contrast, reduced genetic variation would hinder a species' ability to adapt, as there would be fewer traits available for natural selection to act upon. Additionally, a lack of variation could result in uniform traits, potentially making the entire population susceptible to diseases or changes that affect those specific traits.