> The Egyptian and the Sumerian culture were very strongly linked with near identical cultic symbols and building plans for temples up until 3100BC.
There was prehistoric (i.e. pre-writing) trade between Sumer and Egypt. Scholars have argued that the idea of writing based on the rebus principle—but not a specific writing system—may have been communicated one way or another through this trade contact.
Your claim that the cultures were "very strongly linked with near identical cultic symbols and building plans for temples" is a new one for me—and I volunteer at a museum of ancient near eastern archeology. The material culture of pre-Dynastic Egypt and Sumer are rather distinct from each other. And when we do get writing describing their religion, those are also rather distinct from each other.
There was prehistoric (i.e. pre-writing) trade between Sumer and Egypt. Scholars have argued that the idea of writing based on the rebus principle—but not a specific writing system—may have been communicated one way or another through this trade contact.
Your claim that the cultures were "very strongly linked with near identical cultic symbols and building plans for temples" is a new one for me—and I volunteer at a museum of ancient near eastern archeology. The material culture of pre-Dynastic Egypt and Sumer are rather distinct from each other. And when we do get writing describing their religion, those are also rather distinct from each other.