Problem: World Zones
1) Why is it particularly useful to compare civilizations that arose separately in different World Zones (example: to compare the Romans with the Mayans)?
2) What are the Four World Zones?
3) What pieces of land are contained in each one
4) When did humans entered each, and for how long humans in each zone had no contact with humans from other zones,
5) What century they finally came into contact with each other?
6) What is the most important consequence of the unification of the major world zones from c16 (the sixteenth century)?