NEET BIOLOGY

Detailed explanation-1: -Natural selection, genetic drift, and gene flow are the mechanisms that cause changes in allele frequencies over time.

Detailed explanation-2: -One mechanism that drives evolution is natural selection, which is a process that increases the frequency of advantageous alleles in a population. Natural selection results in organisms that are more likely to survive and reproduce.

Detailed explanation-3: -○ Natural selection increases the frequencies of alleles that enhance survival and reproduction. ○ As the proportion of individuals that have favorable characteristics increases over time, the match between a species and its environment improves, and adaptive evolution occurs.

Detailed explanation-4: -When a phenotype produced by certain alleles helps organisms survive and reproduce better than their peers, natural selection can increase the frequency of the helpful alleles from one generation to the next – that is, it can cause microevolution.