Meeting Abstract
Valerianaceae, containing ~300 species, occupy a variety of habitat types across the world, and shows multiple shifts in mating systems. The basal lineages, Patrinia and Nardostachys, are exclusively hermaphroditic, but there was a shift to dioecy early within the clade. Previous studies have shown that dioecy, gynodioecy, and polygamodioecy have evolved independently multiple times. Nowhere is this more apparent than in the southern South American (i.e., Patagonia) radiation of Valeriana. This clade is made up of 40 species, occurring in a wide ecological as well as elevational gradient. For this study, we inferred a phylogeny for this clade based on 5 nuclear regions (accD, Agt1, Chlp, Hmgs, ITS) and 7 chloroplast regions (matK, ndhJ, trnD, trnG, trnK, trnL, ycf5) for 31 of the 40 species. We used BayesTraits to explore a variety of morphological evolutionary hypotheses. We found that the rate of evolution towards a mixed mating system was three times that going from a mixed mating system to an exclusively hermaphroditic system. Likewise, we found no evidence for gynodioecy being an intermediate step to dioecy. We also explore the potential correlation in the evolution of mixed mating systems with several morphological characters (inflorescense, seed morphology) and ecological attributes (elevation, temperature).
