In this paper we presen t a formalizat ion of the specialization process o f o rgan i sms as given by N. Rashevsky. T h i s is done by m e a n s of g lu ing cons t ruc t ions o f g raphs and t hen we formalize the evolut ion of o rgan i sms by successive specialization us ing the concepts o f g raph g rammars . In fact, th is is an extension to h igher d imens ions of developmenta l processes as descr ibed by L s y s t e m s and the deve lopmen t of radial pat terns . T h e g lu ing cons t ruc t ion for g raphs and the algebraically fo rmula ted theory of g raph g r a m m a r s are developed in detail for the special case of unlabe led g raphs in Sections 2 and 4, wh ich can be read separately. In the other three sect ions the theory is applied to processes o f specialization and evolut ion in biology and several i l lustrat ing examples are given.