Stem Groups

Other Groups Under The Crown Group Concept - Stem Groups - Examples
... Stem birds perhaps constitute the most cited example of a stem group, as the phylogeny of this group is fairly well known ... including the extinct moa) Neognathae al(including the extinct dodo) stem group birds crown group birds The crown group here is Neornithes, all modern bird lineages back to their last ... Neornithes to the left, the line itself and all side branches belong to stem-birds until the lineage merges with that of the crocodilians ...

Evolutionary History Of Plants - Evolution of Morphology - Flowers
... only by the angiosperms, which are relatively late to appear in the fossil record the group originated and diversified during the Early Cretaceous and ... hypothesis, and further suggests that gnetales are more closely related to some gymnosperm groups than angiosperms, and that extant gymnosperms form a distinct clade to the ... information Gnetophyta#Classification The relationship of stem groups to the angiosperms is important in determining the evolution of flowers ...