Phylogenetic and environmental lability of flavonoids in a medicinal moss

Flavonoids in the moss genus Plagiomnium were interpreted in the context of a molecular phylogeny to determine correlation with phylogenetic history and ecological context. Flavonoids are weakly correlated with evolutionary history. The rate of evolution of flavonoids is not significantly coupled with the rate of molecular evolution, probably because of high levels of lability and concomitant homoplasy in flavonoid presence-absence. Allopolyploid taxa have additive and intermediate flavonoid profiles. There is no significant correlation between phylogenetic independent contrasts of three indicators of flavonoid content (total phenolic content, number of flavonoids, % luteolin derivatives) and two environmental variables (elevation, latitude). The weak correlation of flavonoids to phylogenetic history and rate of molecular evolution, combined with their lack of correlation with broad-scale ecological features indicates that flavonoid production is labile. As such, flavonoid variation is reflective only of recent evolution (e.g., recent hybridization), and presumably also best correlated with fine-scale ecological features.