Journal Article Research Support, Non-U.S. Gov't Quercus reproductive isolation speciation Erysiphe alphitoides Phytophthora cinnamomi Quercus robur Research Support, U.S. Gov't, Non-P.H.S. approximate Bayesian computation demographic inferences disease resistance diversification rates exapted resistance genome scan genomic mosaicism interglacial recolonization intrinsic and ecological barriers introgression oaks phylogenomics powdery mildew quantitative trait loci (QTL) receptor-like kinase restriction-site associated DNA sequencing (RAD-seq) secondary contact tree diversity