The ultimate owner is what you get when you execute 'aMorph world'. This is the morph that is directly displayed by the main morphic interaction loop. Cycles are not allowed in the submorphs relationship, and so the morphs form a tree with the world morph at the root and submorphs underneath it.
A morph is added as a submorph of another morph using
#addMorph:
or one of its many variants such as
#addMorphBack:
A morph is deleted and removed from its current owner by executing
aMorph delete
Finally, owners and submorphs may be queried using