Molecular Phylogenetics of the Hawaiian Geraniums

by Kidd, Sarah E

The objective of this study was to determine the phylogeny of the Hawaiian Geraniums using ITS regions of nuclear ribosomal DNA, the noncoding chloroplast trnL-F region, and inter-simple sequence repeats in order to understand the pattern of speciation within the group. Results indicated that a clade comprised of G. arboreum and G. c. hypoleucum occupied the basal position. The three bog species appear to have undergone convergent evolution of morphological traits that enable them to adapt to flooded conditions. The frequently occurring “conveyer belt” mode of colonization and radiation from oldest island to newest island is not supported. G. kauaiense, the only species occurring on Kaua’i, was clearly nested and not basal. The data suggests that Maui, Hawai’i, or an older now submerged island is the origin of the radiation.