Final answer:
The most complex forms of political and economic organizations are known as states or nation-states, which emerged as societies became more structured and required centralized governance to manage increased population density and economic activities.
Step-by-step explanation:
The most complex forms of political and economic organizations are typically referred to as states or nation-states. These entities emerged around 5,000 years ago in various parts of the world such as Mesopotamia, China, Egypt, India, Mesoamerica, and South America. They are the result of societies becoming more populous and hierarchical, which led to the development of centralized forms of governance. These complex political systems often include multifaceted economic structures, formal laws, and an expansive bureaucracy. Elman Service, an influential anthropologist, categorized political organizations into four main types: bands, tribes, chiefdoms, and states, which can be considered a spectrum of sociopolitical complexity. The evolution from simpler forms like bands and tribes to more complex forms such as chiefdoms and ultimately states, is often associated with the emergence of agriculture and the need for managing larger populations and more diverse economies. The nation-state form of political organization has spread globally, especially during the period of colonialism, incorporating or replacing other forms of governance. In today's world, states are the predominant form of economic and political organization, though alternative systems and values still persist and influence contemporary society.