Phylogenetic analysis Allele frequency distribution analysis Analyse a phylogenetic tree to identify allele frequency distribution and change that is subject to evolutionary pressures (natural selection, genetic drift, mutation and gene flow). Identify type of natural selection (such as stabilizing, balancing or disruptive). Stabilizing/purifying (directional) selection favors a single phenotype and tends to decrease genetic diversity as a population stabilizes on a particular trait, selecting out trait extremes or deleterious mutations. In contrast, balancing selection maintain genetic polymorphisms (or multiple alleles), whereas disruptive (or diversifying) selection favors individuals at both extremes of a trait. beta12orEarlier Phylogenetic tree analysis (natural selection)