Large-scale phylogenetic relationships link to the chemical niches of epiphytic macrolichens

This study aims to elucidate the connection between the phylogeny of epiphytic macrolichens and their chemical niches.We assessed published floristic and environmental data from ninety canopies of<i>Picea</i>x<i>darwyniana</i>across a range of forest settings in British Columbia. Procrustean randomization tests were employed to investigate the concordance between a principal coordinates analysis of the cladistic distance matrix and a global non-metric multidimensional scaling of the ecological distance matrix.The research uncovers a robust association between large-scale macrolichen phylogeny and canopy throughfall chemistry. The calcium-scores of the species examined separated members of the orders Peltigerales and Lecanorales. However, the chemical factors associated with Ca, such as Mn, Mg, K, bark-, and soil-pH, cannot be excluded as contributing factors for the niche partitioning. Finally, the study also identifies minor species-specific variations in Ca-scores within orders and families.While substantial large-scale phylogenetic variation in the macrolichens’ Ca-scores is consistent with ancient adaptation to specialized chemical environments, minor variation within genera suggests some additional recent adaptation. The study highlights the value of lichens as transferable bioindicators for the chemical environment and underlines the importance of understanding the intricate interplay between chemical factors and lichen evolution.