Dating dispersal and radiation in the gymnosperm gnetum
Efforts to resolve Darwin's “abominable mystery”—the origin of angiosperms—have led to the conclusion that Gnetales and various fossil groups are sister to angiosperms, forming the “anthophytes.” Morphological homologies, however, are difficult to interpret, and molecular data have not provided clear resolution of relationships among major groups of seed plants.
We also considered certain fossil Mesozoic conifer cones, which shed further light on the evolution of the cupressaceous cone.
The evidence from these various genera strongly indicates that recently reconstructed phylogenies of gymnosperms based on molecular evidence from extant taxa do not reflect the evolution that actually happened.
Some species have been proposed to have been the first plants to be insect-pollinated as their fossils occur in association with extinct pollinating scorpionflies.
Molecular phylogenies based on nuclear and plastid sequences from most of the species indicate hybridization among some of the Southeast Asian species.
We introduce two sequence data sets from slowly evolving mitochondrial genes, A also strongly support a gnetophyte–conifer grouping.