Date of Award
Doctor of Philosophy
Ecology and Evolutionary Biology
Patrick B Matheny
Randall L. Small, Ernst C. Bernard, Joseph H. Williams
The recent advent of molecular tools and methods to understand the diversity of living organisms allows for exploration of former untestable theories concerning the diversity of fungi. Here we assess the morphologically based classification of the family Clavariaceae in light of molecular phylogenetic reconstruction and propose a revised classification base on natural assemblages. We used stable isotope ratios to uncover a biotrophic nutritional mode for much of the family, which had not been well understood historically. We also investigate several enigmatic lineages of agaricoid or cantharelloid fruiting body producing fungi within a clade of otherwise clavarioid fruiting bodies. We provide the first (partial) support for the Corner hypothesis of morphological evolution. We uncover up to three transitions to agaricoid clades and one transition to a cantharelloid clade. We present a new generic classification for agaricoid clades including the discovery of a new genus and species. Finally we explore the effects of morphology and ecology on diversification rates to explore what traits may be driving patterns of diversity found in the Agaricomycetes. Bayesian Analysis of Macroevolutionary Mixtures (BAMM) and State Speciation and Extinction (BiSSE and MuSSE) analyses were performed on time-calibrated phylogenies of two morphologically and ecologically diverse lineages (the Clavariaceae and the Cantharellales) to test hypotheses that changes in nutritional mode, fruiting body morphology, and hyemnial configuration are associated with shifts in diversification rate. We find that a biotrophic nutritional mode is consistently associated with increased diversification rates while fruiting body morphology and hymenial configuration are only associated with shifts in the Cantharellales.
Birkebak, Joshua Mark, "Systematics and diversification patterns of morphologically and ecologically diverse lineages of Agaricomycetes: Clavariaceae and Cantharellales. " PhD diss., University of Tennessee, 2015.