Phylogenetic relationships and character evolution in Heuchera (Saxifragaceae) on the basis of multiple nuclear loci

Premise of the study: The use of multiple genetic regions from the nuclear genome, including low-copy markers, has long been recognized as essential to robust phylogenetic construction, addressing gene tree incongruence, and allowing increased resolution to test current taxonomy and resolve basic hypotheses about character evolution, biogeography, and other organismal traits of interest to biologists. Heuchera, the largest genus of Saxifragaceae endemic to North America, has presented an unusually difficult case for systematists with limited sampling in previous molecular studies. We used morphological and multilocus molecular phylogenetic data to test the monophyly of Heuchera, better resolve hypotheses of relationships, and test hypotheses of character evolution, biogeography, and diversification rates. Methods: Phylogenetic relationships were inferred using sequences from six nuclear loci and 39 morphological characters using concatenation and coalescent analysis. Ancestral state rec...