Integration of morphological and ribosomal RNA data on the origin of angiosperms

TitleIntegration of morphological and ribosomal RNA data on the origin of angiosperms
Publication TypeJournal Article
Year of Publication1994
AuthorsDoyle JA, Donoghue MJ, Zimmer EA
JournalAnnals of the Missouri Botanical Garden
Pagination419 - 450

Previous phylogenetic analyses of morphological and rRNA data indicated that Gnetales are the closest living relatives of angiosperms but gave different basal angiosperm relationships. A two-step morphological analysis of seed plants (including fossils) and angiosperms rooted the latter near Magnoliales, with tricolpate eudicots and paleoherbs (herbaceous magnoliids and monocots) forming a clade, whereas analyses of rRNA sequences rooted angiosperms among paleoherbs, with eudicots and woody magnoliids forming a clade. Experiments with a revised seed plant morphological data set raise further questions: when angiosperms are scored like different angiosperm subgroups, they associate with different outgroups, although Gnetales are their closest living relatives. To test whether morphological and rRNA data are seriously contradictory or rather complementary, with inconsistencies being a function of better resolution in different parts of the tree, we experimented with morphological and rR