Fig. 2.
Divergence time and demographic history of Hawaiian Metrosideros. Relative times were converted to absolute times assuming a mutation rate of 7 × 10−9 mutations per base pair per generation and a 20-y generation time. (A) Genome-wide maximum-likelihood tree built using fourfold degenerate sites. A tree with branch lengths is shown on left and a tree without branch lengths but showing phylogenetic relationships with bootstrap is on Right. Outer circle colors indicate island of origin for each sample, and inner circle colors indicate taxa as in Fig. 1B. All Hawaiian Metrosideros taxa have glabrous (hairless) leaves, except the four Oahu pubescent taxa indicated in the outer-most ring of Left tree. The four Oahu glabrous taxa are also highlighted in outer-most ring of Right tree. Nodes with greater than 95% bootstrap support are indicated with blue circles in Right. (B) G-PhoCS-estimated divergence times for representative taxa/populations GH1 (M. polymorpha var. glaberrima from Hawaii), GM (M. polymorpha var. glaberrima from Molokai), M (M. macropus from Oahu), and GK (M. polymorpha var. glaberrima from Kauai) (Above) and time of geological formation of each island based on Clague (102) (Below). Tree is rooted with outgroup M. vitiensis (Mv). (C) MSMC2-estimated effective population size for each Hawaiian taxon, color-coded as in Fig. 1B.