Final answer:
Great Britain's royal family exemplifies a dynastic family, which has transitioned from a historical closed system of primogeniture to a modern constitutional monarchy with ceremonial roles.
Step-by-step explanation:
Great Britain's royal family is an example of a dynastic family. This form of monarchy played a significant role in historical societal structures, particularly in Europe during the Middle Ages. The British monarchy, specifically, was once considered a closed system where positions of nobility were inherited, with the primogeniture law favouring firstborn sons for inheritance. This established a largely patriarchal society, placing royalty at the top and commoners at the bottom. Modernly, the British monarchy has evolved into a constitutional monarchy, acting within the confines of a constitution and possessing limited actual governing power.