The APG phylogeny has separated plant orders and families on a linear time scale
into basal angiosperms, eudicots, early diverging dicots, and core dicots. Research
supporting APG (Soltis and et al., 2005) considers the rosids, of which rosales and
its typical family, Rosaceae to be of the core eudicot group. Although the Rosaceae
has great morphological diversity, to the point of being “indefinable” (Dickinson
et al., 2002), the family is robust as along with morphological and chemical assessments
(Challice, 1974), analyses of rbcL sequences strongly support the monophyly
of Rosaceae (Fig. 1) (Morgan et al., 1994).