Random mutations are changes that occur in the DNA sequence of an organism. These changes can happen due to various factors, such as errors during DNA replication or exposure to environmental influences like radiation. Most mutations are neutral, meaning they do not significantly affect the organism, while some can be harmful or beneficial. Over time, random mutations contribute to the genetic diversity of a population. This diversity is essential for evolution, as it provides the raw material for natural selection. When a mutation offers an advantage in a specific environment, it may become more common in future generations, influencing the evolution of species like Darwin's finches.