Groups of organisms must be defined by the selection of important characteristics, or shared traits, that make the members of each group similar to one another and unlike members of other groups.
(Groups of organisms; must be defined; by the selection of important characteristics, or shared traits) (shared traits; make; the members of each group similar to one another)
Groups of organisms shared traits
must be defined make
by the selection of important characteristics, or shared traits
the members of each group similar to one another