Orthologous sequences provide useful information in taxonomic classification and phylogenetic studies of organisms. The extant families are monophyletic according to phylogenetic molecular analysis. The rosids are monophyletic based upon evidence found by molecular phylogenetic analysis. Modern systematics aims to reflect and discover phylogenetic relationships between plants. When subjected to molecular phylogenetic analysis only Thalictroideae is monophyletic. Evolutionary trees are hypotheses that are inferred through the practice of phylogenetic theory. See Herpesvirales#Taxonomy for information on taxonomic history, phylogenetic research, and the nomenclatural system. There is a poor correlation between sections and phylogenetic clades. Lineages are typically visualized as subsets of a phylogenetic tree. Alignments are also used to aid in establishing evolutionary relationships by constructing phylogenetic trees. Versions of the phylogenetic species concept may emphasize monophyly or diagnosability. Heme oxygenase is conserved across phylogenetic kingdoms. Phylogenetic or typological comparisons of creole languages have led to divergent conclusions. Hennig referred to his own approach as "phylogenetic systematics". Phylogenetic and molecular analysis with other primates has been done.