Complete the passage by writing a suitable word in each of the spaces.

• New alleles that introduce genetic variation into a population's gene pool arise through random DNA __________.
• Individuals whose inherited phenotypes are well-suited to selection pressures are more likely to __________ and reproduce.
• Consequently, these individuals have a higher probability of passing their advantageous alleles to their __________.
• Over many generations, the progressive shift in allele frequencies within the population results in __________.