<p>Estimated using a linked-tree BEAST analysis of COI-barcode and PEPCK exon and intron sequences for each species. Values below the nodes are Bayesian posterior probabilities showing branch support. Numbers above the nodes show the estimated dates of divergence events in Ma (millions of years before the present) calibrated with a molecular estimate for the date of divergence between the subgenus <i>Alpinobombus</i> and the subgenus <i>Bombus s</i>. <i>str</i>. from Hines (2008) and grey bars show the 95% confidence limits on the estimated dates of divergence.</p
